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prof. Ing. Jaroslav ELIÁŠEK, DrSc.


prof. Ing. Jaroslav ELIÁŠEK, DrSc.(*1924 - †1995)

1966 - 1986  vedoucí Katedry tepelné techniky

1964 – 1969 proděkan FTPV

1969 – 1973 děkan FTPV

Narozen v roce 1924 v Českém Krumlově.

Absolvoval vyšší průmyslovou školu chemickou v Praze a Fakultu chemicko-technologického inženýrství ČVUT v Praze. Poté působil několik let v průmyslu a po obhájení kandidátské disertační práce se stal odborným asistentem na Katedře tepelné techniky a od roku 1966 se stal jejím vedoucím. Po obhájení habilitační práce v roce 1962 byl jmenován docentem pro obor „Tepelná technika“. V roce 1978 obdržel titul doktora věd na základě obhájení doktorské disertační práce na téma „Kinetika výměny iontů“. V roce 1979 byl ustanoven profesorem pro obor „Tepelná technika“.

V roce 1982 mu byla udělena medaile prof. Ferdinanda Schulze.

Matějka, Z., Eliasek, J.  Separating heavy metals from complex-forming substances such as aminocarboxylic acids or their salts in aqueous solutions (1985) patent DE 3517400 A1 19851205.  

Heavy metals are sepd. from complexing materials, esp. aminocarboxylic acids, by ion exchange using a resin with chelate-forming polyethyleneimine groups and subsequent elution with acid soln. at 0.5-30% with optional pretreatment for selective elution by contacting with an aq. soln. contg. K, Na, Ca, or Mg as Cl-, SO42-, or NO3- at 0.01-10 M or with pretreatment before ion exchange by addn. of a soln. contg. Ca or Mg as Cl-, SO42-, NO3-, HCO3-, or oxide at 0.1-100 mM.  The exchanger is regenerated with an aq. soln. contg. alkali metal hydroxide carbonate, or hydrogen carbonate 0.5-30%.  Thus, Cu was sepd. from a plating bath contg. Cu 0.5 mM and EDTA 0.55 mM at pH 8.9 by ion exchange at 150 mL/h with resin contg. tetraethylenepentamine groups.  The resulting bath concn. was 0.1 mg/L after 36 column vols.  Elution was with 1.5 M H2SO4 120 mL, at 60 mL/h.

Nemcova, J., Bartonicek, R., Holinka, M., Sverepa, O., Mostecky., Pelikan, J., Vosta, J. Panacek, F., Eliasek, J.; et al. Corrosion inhibitor for brass with a biocidal effect (1985), patent CS 222108 B1 19830429.

Corrosion inhibitors contg. alkanolamines, C12-18 alkylamines, mercaptobenzothiazoles, and surfactants prevent dezincification of brass ducts and condensers as well as their fouling with biol. deposits.  Thus, triethanolamine [102-71-6] 54 was mixed at 60° with C18H37NH2  [124-30-1] 3 and 2-mercaptobenzothiazole  [149-30-4] 43. The mixt. was stirred at 60° for 2 h, cooled, and mixed with monoethanolamides of coconut acids 43 parts at 40°.  Using this mixt. in a brass cooler at 20 ppm in water gave 98% corrosion inhibition and 70% suppression of microbial growth.

 Kulhavy, T., Brodsky, A., Bartonicek, R., Panacek, F., Sladeckova, A., Eliasek, J. Device and method for protecting water cooling systems (1984), patent CS 216564 B1 19821126.

A method is described which prevents corrosion, incrustation, and biol. fouling in water systems in which the circulating water is replenished from natural sources of surface waters.  It comprises periodical feeding of an antimicrobial agent, such as NaClO, passing through a magnetic field, filtration, addn. of Na Ca polyphosphate, and treatment with a dispersing agent, such as polyethylene polypropylene glycol  [9003-11-6].

Matejka, Z., Eliasek, J.  The use of bead cellulose anion exchangers for ultra-pure water production (1984) Ion Exch. Technol. , 153-9.

The ability and efficiency of the bead cellulose anion exchangers to take up higher-mol.-wt. humic acids were investigated.  Desorption of these substances from cellulose resins proceeds almost quant.  Sorption capacity toward low-mol.-wt. acids is rather poor.  Equil. sorption and desorption tests, comparative dynamic (column) runs with styrene and cellulosic resins and gel chromatog. anal. of the raw and treated water proved the suitability of the bead cellulose resins to act as a simple and cheap substitute for flocculation in the prodn. of ultrapure water.

 Bischof, V.; Eliasek, J. Genesis of the protective layers upon the mild steel surface in the neutral natural waters (1984) Acta Hydrochimica et Hydrobiologica 12(5), 531-7.  

The formation of a protective layer on mild steel in neutral water (with and without Cl-) is controlled by the concn. of Ca2+ and HCO3- ions, which form layer components of CaCO3 and FeCO3.  Nonstoichiometric hydrated magnetite is formed at 1st, but is gradually oxidized and changes to FeOOH.H2O.  Natural water components increase the oxidn. rate, yield crystn. nuclei, and affect the structure of compds. formed during corrosion reactions.  The formation of scale in cooling systems is discussed.

Nemcova, J., Holinka, M., Mostecky, J., Pelikan, J., Vosta, J., Eliasek, J., Smrz, M., Lohnisky, J., Novotny, M., Mencl, F., Corrosion inhibitor for aqueous heat exchange media in bras (1983), patent CS 211962 B1 19820226.

The corrosion inhibitor contains aliph. amines, arom. azoles, surfactant, polymer, and quinoline or derivs.  Thus, 1000 m3 of cooling water was treated with octadecylamine  [124-30-1] 0.9, diethanolamine  [111-42-2] 0.5, 2-mercaptobenzothiazole  [149-30-4], 0.2, 1,2,3-benzotriazole  [95-14-7] 0.2, coconut acid diethanolamide 0.05, polyacrylamide  [9003-05-8] 0.05, and quinoline  [91-22-5] 0.1 kg.  The treatment had a 97% corrosion-inhibiting effect and did not remove Zn from the brass surface.

Ocenasek, M., Stonawski, J.,  Eliasek, J. Use of cation exchangers for treatment of wastes from nuclear power stations.  1.  Effect of citric and oxalic acids on the sorption of some cations Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1982), D45, 153-76.

The use of strong acid cation exchangers for concn. of radioactive nuclides from chem. decontamination of the primary cycle of the nuclear power station was examd.  Ni(II), Co(II), Fe(III), and Cr(III) either were sepd. or in the mixt. were sorbed from their 0.0025-0.005M solns. in H2O, in 0.05M citric acid, or in 0.04M oxalic acid by gel-type Lewatit S 100 or macroreticular Wofatit KS 10 in H+ forms.  In the presence of the org. acids the sorption of Ni(II) and Co(II) was unchanged but Fe(III) and Cr(III) were sorbed incompletely.  The metals could be eluted with HCl or with large excess of HNO3.

Macura, J., Matejka, Z., Eliasek, J. Ion exchange kinetics in multicomponent systems on strongly acidic cationic exchange resins Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1982), D45, 135-52.  

Ion exchange kinetics in the systems H+-Na+, H+-Ca2+, and H+-Na+-Ca2+ were studied at 25° with the use of strongly acidic cation exchangers.  The effects of the particle size, degree of netting, concn. of the ions and acidity were studied on the exchange rate with the exchanger in spinning bed.  The H+-ion exchange is inhibited by soln. acidity.  The H+-Ca2+ exchange rate exhibits an anomalous increase in the pCH+ interval 2.0-1.7.  The kinetic dependences in the H+-Na+-Ca2+ system passes through a max., the height of which is directly proportional to the Na+ concn.

Herrera, T.,  Matejka, Z. Eliasek, J. Cation exchange kinetics on carboxylic acid resins in a multicomponent system ‾H-M+-M2+ Desalination (1983), 48(2), 161-9.  

The exchange kinetics in systems where a carboxylic cation exchange resin in the free acid form comes into contact with solns., contg. Na+, Mg2+, Ca2+, HCO3- and SO42- were followed by a shallow bed technique.  The relation between the sorption rates of univalent and divalent cations as well as kinetics of competitive exchange in a ternary system ‾H-Na+-Mg2+ were studied at low soln. concns.  The effect of polymer matrix crosslinking was also studied.  The behavior of a sulfonic acid resin under the same conditions was given for comparison. The results were discussed in terms of different degrees of selectivities and degrees of dissocn. of the carboxylic and sulfonic functional groups.

 Matejka, Z., Pechova, M., Eliasek, J. Effect of a quaternary surfactant upon the kinetics of proton-magnesium(2+) ion exchange on sulfonic acid cation exchangers Reactive Polymers, Ion Exchangers, Sorbents (1983), 1(3), 207-13.

The dynamic and static effect of a quaternary surfactant on the rate of H+-Mg2+ exchange on sulfonic acid cation exchange resins of various porosity (gelular and macroporous) in the ranges of film diffusion control and particle diffusion control has been investigated.

Matejka, Z.; Eliasek, J.  Liquid-side diffusion-controlled cation-exchange kinetics.  Comparison between macroporous and gelular resins Desalination (1982), 42(3), 315-20.

The rates of H+-Mg2+ exchange at low soln. concn. on several styrenesulfonic acid resins with either a macroporous or gelular matrix were measured by the shallow-bed technique.  The kinetics of Mg2+ uptake on macroporous and gelular resins were compared.  The location of the liq.-solid interphase in the resin bead, where the ion diffusion rate controlled the overall exchange rate, was estd.

Panacek, F., Kocica, J., Eliasek, J. The use of phosphonates for the treatment of cooling waters Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1980), D 41, 5-15.  

Corrosion inhibiting action of several com. compds. contg. phosphonic acid used for treatment of water in open circulating cooling systems was evaluated from the wt. loss of a rotating disk and wt. loss of steel specimens in flowing water at 23°.  The latter had a hardness of 3.2-3.5 mequiv/L and alky. 2.1-2.5 mequiv/L.  The concn. of the inhibitors Ferrofos 509, Ferrofos 510, Nalco 4000, and Nalfloc 345 was 10-1000 mg/L.  Effect of Zn2+ was examd.  The highest corrosion inhibitor of ≤98.9% was obtained for combinations of 50 Ferrofos 509 or Ferofos 510 and 3 mg ZnSO4/L.

Vosta, J. Pelikan, J. Eliasek, J. Corrosion inhibition Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1980), D 41, 83-103.  

 A review with 119 refs. on the mechanism of corrosion and classification of corrosion inhibitors is given.

Matejka, Z., Eliasek, J. Kinetics of sorption and desorption of hydrochloric acid and low molecular weight organic acids by styrene and acrylic weak base resins Water Research (1980), 14(5), 467-70.  

Several important parameters for the operation of ion exchange resins in water treatment, such as breakthrough capacity, max. flow rate, and efficiency and reversibility of org. matter sorption and desorption, exhibit a close connection with the ion exchange rate.  Therefore this value, expressed as the exchange half-time (t0.5) can be used as a criterion for a proper resin type choice and can also help to judge its use for obtaining treated water of required compn.  The sorption and desorption rates of HCl  [7647-01-0], caproic acid  [142-62-1] and sulfonsalicylic acid  [97-05-2] by styrene and acrylic weak base resins were estd., and the results obtained with particular resins were compared.  Attention was paid to the effect of gelular and macroporous matrix and soln. concn.  Acrylic resins are preferable for sorption and desorption of HCl at low concns., at higher concns. macroporous-styrene resins are better.  Sorption of low-mol. org. acids is primarily controlled by selectivity and proceeds faster on acrylic resins at all concns.  Desorption is governed by the concn. of the elution soln. rather than by selectivity and occurs faster on macroporous styrene resins.  The macroporous matrix generally has a substantially smaller kinetic advantage when using acrylic rather than styrene weak base resins.

Matejka, Z.; Erlebach, J.; Savvides, K.; Ioannis, H.; Eliasek, J. Regeneration of the acrylic weak base anion exchange resin by means of sodium carbonate  Acta Hydrochimica et Hydrobiologica  (1980), 8(2), 187-90.  

The mechanism of regeneration of a weakly basic acrylic anion exchangers, such as Wofatit Y 17  [70088-55-0] by Na2CO3 is presented and discussed.

Pelikan, J., Vosta, J., Panacek, F., Eliasek, J., Mostecky, J. Corrosion inhibitor (1978), patent CS 174913 B1 19770429.  

Mixts. of (NaPO3)6  [10124-56-8] 4-67, KMnO4 0.5-22, and/or KClO3 10-35, and/or optionally Na silicate 16-80 and CaCl2 0.1-3% inhibits the corrosion of steel  [12597-69-2] surfaces by road deicing mixts. and cooling salt solns.

Talasek, V., Vosta, J., Eliasek, J., Mostecky, J.,Ocenasek, M., Matejka, Z.Treatment of surface waters and power engineering condensates containing organic cations  (1978), patent CS 171820 B1 19761129.  

Polluted waters are passed through a mixed bed contg. a macroporous strongly acid cation exchanger (A) and a gel cation exchanger (B).  The loose inner structure of the macroporous ion exchanger permits reversible sorption and easy desorption of large org. cations and protects the gels from contact with dissolved org. substances.  Macroporous Lewatit S 100X10/50  [68517-53-3] (cross-linked with 10% divinylbenzene) or a combination of Lewatit CNP  [56940-15-9] with Zerolit 225  [37206-32-9] are used for A and the gel cation exchanger Lewatit S 100X10  [68517-52-2] for B.

Eliasek, J. Matejka, Z. Tejchman, P. Reaction kinetics of weakly basic anion exchange resins Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1977), D 35, 43-59.  

The kinetics of sorption and desorption of HCl at different concns. was studied for anion exchange resins with different structures (Wofatit AD 41, Lewatit MP 62, Amberlite IRA 93, Amberlite IRA 94S, Amberlite IRA 45, Zerolit HIP-isoporous, Amberlite IRA 68, and Lewatit CA 9222).  Relations modified for the method of the infinite soln. vol. were used for detn. of the controlling process of sorption.  The controlling process is the diffusion through a particle; only in the case of the monofunctional styrene gel resin Amberlite IRA 45 was the sorption controlled by reaction with a functional group.  Electrolyte invasion causes higher sorption and desorption rates of the styrene macroporous anion exchange resins in comparison with the gel types. The sorption rates of acrylate resins are high, esp. in the region of low concns., in spite of a lower effect of the electrolyte invasion.  The resin porosity has more effect on the sorption rate than the basicity index does.

Eliasek, J. Matejka, Z. Kinetics of copper uptake from nitrilotriacetic acid medium on cation exchange resins  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1977), D 35, 35-42.  

Cation exchange resins (Lewatit S 100, Lewatit TP 207) were used for Cu uptake from complexes with org. acids used for the surface treatment of metals in the electroplating industry.  The rate of Cu uptake was detd. in relation to pH and the presence of Na in a soln.  The strongly-acidic Lewatit S 100 can be used only in the H-form, which can secure the necessary decrease in the complex stability.  If there is an excess of NTA in the soln., then Cu will pass (depending on the concn. of the accompanying cations) again into the complex with NTA.  The chelating iminodiacetate resin Lewatit TP 207 collects Cu more slowly, but the reaction is not affected either by accompanying cations or excess NTA.

Eliasek, J.,  Panacek, F., Kocica, J. Effect of flow on corrosion rate of steel in inhibited sulfuric acid  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1977), D 35, 5-21.  

The rate of corrosion depends on the compn. of the material, its surface characteristics, temp., heat transfer and flow rate of the corrosive medium.  The flow effects esp. the processes in the region of the electrodes. Through the flow, the reaction products are removed and inhibitors are shifted to the metal-liq. interface.

Eliasek, J.,  Kocica, J.Panacek, F., Vcelak, L. Effect of flow in neutral environment on steel corrosion and its inhibition  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1977), D 35, 23-33.  

The effect of flow on the corrosion rate of steel was studied in neutral 0.1 and 1% NaCl satd. with air at 25°.  In these solns. the most significant effect on the corrosion rate is the concn. of O.  O functions as a cathode depolarizer on the metal surface.  The corrosion rate of steel was dependent on the Re0.5 value.  Inhibitors for neutral solns. are K2CrO4 and Na3PO4.  Addn. of  K2CrO4 (≥10-4M) is 95% effective.  Na3PO4 on the other hand is less effective and in concn.

Eliasek, J.; Matejka, Z. Kinetics of ion exchange.  X.  Effect of electrolyte invasion on the ion exchange rate of a strongly acidic cation exchanger Collection of Czechoslovak Chemical Communications  (1977),  42(6), 1782-5.  

The conditions under which electrolyte invasion affects the exchange rate, even in the case of strongly acidic cation exchangers, were investigated.  The exchange rates of gel exchangers (Dowex 50X8, Dowex 50X16) and macroporous cation exchangers (Amberlite IR 200 with 22% divinyl benzene) were compared, employing different compns. and concns. of the external electrolyte solns.  The exptl. conditions ensured the exchage rate to be controlled predominantly by the particle diffusion.  Under certain conditions, the exchange rate of the macroporous exchanger is higher than that of the gel exchanger contg. the same amt. of the cross-linking agent.  This effect depends on the soln. concn. and the charges of the counterions, or the exchange rate of the macroporous exchanger is affected by the electrolyte invasion.

Vosta, J., Eliasek, J.,  Knizek, P. A quantum-chemical study of the corrosion inhibition of iron by means of aniline derivatives in hydrochloric acid Corrosion (Houston, TX, United States) (1976), 32(5), 183-7.  

To det. the mechanism of corrosion inhibition by org. materials, the electron structure of a set of org. compds. is studied and correlated with their electrochem. corrosion measurements.  The inhibition of corrosion of Fe in 5% HCl by p-substituted anilines with respect to quantum chem. is discussed.  Fe2+ ions originating from the dissoln. of Fe form complex Fe(Cl)64- ions on the metal surface at anodic centers.  The protonized aniline mols. are then electrostatically bonded to these complex ions.  Thus, a potential barrier is formed which prevents the corrosive medium from reacting with the metal surface.

Matejka, Z.,  Ocenasek, M., Eliasek, J., Mostecky, J., Uher, J., Prokupek, J., Tuna, J. Simultaneous removal of aldehydes, ketones, and acids from solutions by anion exchangers  (1974), patent  DE 2426274  A1 19741205.  

Oxo compds. are removed from aq. or nonaq. solns., e.g., paper industry waste water, by weakly or moderate basic anion exchangers in the HSO3 form, because of strong retention of the formed α-hydroxy sulfonic anions by the exchangers.  Optionally, a weakly basic anion exchanger is converted to the HSO3 form by the SO2 in the soln.  By the use of weakly instead of strongly basic exchangers the effective vol. capacity was increased.  Thus, a soln. contg. 42 mequiv. AcOH/l., 2 mequiv. HCO2H/l., 5 mmoles MeCHO/l. and 10 mmoles SO2/l. was passed over a weakly basic anion exchanger (Wofatit AD 41) in form of the free base at sp. load 10 l./hr/l.  The exchanger had effective vol. capacity 1.03 equiv./l.

Eliasek, J., Kocica, Jo., Panacek, F., Pelikan, J., Vcelak, L. Evaluating oxide layers in boiler tubes of steam generators Acta Hydrochimica et Hydrobiologica (1974), 2(3), 249-59.  

Exptl. results show a consolidation of the protective coating with increasing temp., heat loading, steam dryness, and time of exposure.  Disturbances in water circulation have a neg. effect on oxide-coating formation by leading to an increased thickness and porosity as well as to a lowering of the corrosion resistance.  The presence of primary corrosion products in the water phase result (in the absence of added corrosion products) in the formation of thick, porous coatings on the surface of the metal.  A comparison between equil. corrosion current, layer thickness, and corrosion resistance values show the first to be most useful as a measure of porosity of the protective layer.  X-ray studies of the oxide layers show the protective layer to be composed preferentially of magnetite.  Under industrial working conditions a thick, amorphous, Cu contg. coating is found, whose pores are nonhomogeneous and whose evaluation is more complex, magnetite being the preponderant constituent.  It is difficult to bring equil. corrosion current values into agreement with apparent thickness and corrosion resistance under these conditions.

Eliasek, J., Vosta, J., Talasek, V., Mostecky, J. Agent for protection of hot water lines (1974), patent CS 153733 B1 19740329.  

A 1:5 mixt. of octadecylamine and Na polyacrylate or polymethacrylate of mol. wt. 10,000-25,000 was added to distd. water to form a colloid suspension and fed into the pipes.  The agent prevented incrustations and corrosion in amts. of 6 g/ton water.

Vosta, J., Talasek, V., Mostecky, J., Eliasek, J., Panacek, F., Singer, P. Mixed corrosion inhibitor (1973), patent CS 151601 B1 19731119.

The mixed corrosion inhibitor consists of evapn. inhibitors (e.g., piperdine, nitrite, or cyclohexylamine nitrite), bivalent anions (e.g. chromates, tungstates) combined with NaNO2, silicates, phosphates, urea and its derivs., hexamethylenetetramine, and optionally volatile bases (e.g. piperidine, cyclohexylamine, NH4OH) and org. peroxides (e.g., perbenzoic acid and/or its salts, dibenzoyl peroxide).  Thus, metal sheet was protected by a passivation inhibitor contg. piperidine nitrite 0.65, cyclohexylamine nitrite 1.45, Zn hexametaphosphate 0.8, and piperidine 0.01 g/l.

Sejnoha, R., Talasek, V., Vosta, J., Eliasek, J., Vcelak, L. Cleaning of sewage drains (1973), patent CS 149103 B1 19730524.

Sewage drains were cleaned by circulation of 5% aq. HCl or H2SO4 contg. 0.2-0.3% dibenzyl sulfoxide [621-08-9] 15-20 min at 20-75.deg., followed by rinsing with water and treating with 5% Na nitrite [7632-00-0].

Eliasek, J., Mostecky, J., Vosta, J., Talasek, V., Singer, P., Voldrich, K. Corrosion inhibitor and passivator for metals (1973) patent CS 149254 B1 19730524.

Octadecylaminophosphate is esp. effective in steam lines owing to the double effect of Na phosphate, liberated by addn. of a calcd. amt. of NaOH, and of octadecylamine which volatilizes in steam and protects the condensor tubes from corrosion.  Other useful applications are in automotive cooling systems and in cooling of nuclear reactors contg. D2O and CO2.

 Mostecky, J., Vosta, J., Talasek, V., Eliasek, J., Matejka, Z. Selective recovery of nonferrous metals from industrial waste waters (1972), patent CS 145167 19720915.  

Approx. 80-5% Mn, Cu, and Zn were recovered from washing and recycled waters of ore-processing plants by passing through chelation ion exchangers contg. iminodiacetate of carboxylic group in Na cycle.

Vosta, J.,  Eliasek, J.,  Mostecky, J. Inhibitors of metal corrosion in acid solutions  (1972), CS 144135 19720101.  

Mesoionic compds. with dipole moments, >6 D have a high corrosion-inhibiting effect owing to their amphoteric properties.  This makes preliminary orientation of the inhibitor mols. on the metal surface unnecessary and speeds up the inhibition process.  Solns.  of 0.02% nitron in 5% HCl and 0.03% sydnone in 15% H2SO4  have a good corrosion inhibiting effect.

Vosta, J.; Eliasek, J. Study of corrosion inhibition from the quantum chemistry aspect, Edited by Hamner, Norman E.,  Proc. Int. Congr. Metal. Corros., 4th (1972), 598-601.  

Quantum chem. values for the pyridine N-oxides of parasubstituted N(CH3)2, SH, CN, Me, and NO2 were correlated with the inhibition efficiency detd. by polarization curves on an Armco Fe electrode in 5%  HCl at 25°. Results showed the inhibition efficiency depends on the energy of the HOMO (highest occupied MO) and LFMO (lowest free MO).

Talasek, V.; Eliasek, J. Kinetics of ion exchange.  IX.  Reactions taking place between the undissociated forms of exchange groups of chelating exchangers  Collection of Czechoslovak Chemical Communications (1972), 37(8), 2521-7.  

The rates of exchange between the Ca-forms of the cation exchangers Dowex A-1 and Duolite ES-63 and the counterions Mn2+ and Cu2+ were measured.  The exchange kinetics is controlled by the diffusion through particles of the exchanger.  The rate of exchange decreases with decreasing concn. of the outer soln. owing to the reduced electrolyte invasion into the exchanger phase.  With the Dowex A-1, a chelate is formed between the metal cation and the exchange group of the exchanger and the differences of the diffusion rates on reversing the direction of the exchange are detd. by the ratio of the stability consts. of the chelates of both counterions.  With the Duolite ES-63, an inversion of the ion exchange takes place in the Ca-Mn system which depends on the acidity of the exchange groups.

Talasek, V., Eliasek, J. Diffusion of differently substituted organic bases on cation exchangers of different structures  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1972), D25, 17-25.  

Equil. and kinetic measurements of gel diffusion were carried out on Lewatit S 100 with gel and macroporous structure with different cross-linkages in the triethanolammonium (TEA+) and (or) anilinium systems.  In TEA+, a selectivity inversion was obsd., accompanied by the inversion of the exchange and the differential diffusion rates, which in both systems, with the exception of the macroporous low cross-linked ion exchanger, varied considerably with the change in compn. of the ion exchanging phase.  With the aromatic base, considerable dependence of activation energy on the direction of exchange was found.

Panacek, F.; Kocica, J.; Eliasek, J. Necessity of cleaning steam generators Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1972), D25, 37-48.  

The evaluation of tube samples taken periodically during shutdown of steam generators is used to indicate the possible need for chem. cleaning.  The most significant values are the wts. and elec. resistance of the oxide layers.  In elec. nonconductive deposits, a lower thermal cond. may be expected, the decrease in both the elec. and the thermal cond. being caused by the porosity of the oxide layers. Consequently, the elec. resistance of the oxide layer is a measure of the thermal cond. of the oxide layers.  The elec. resistance of the oxide layers can be detd. more easily than the thermal cond.  Other properties evaluated, such as corrosion resistance, chem. compn., and thickness serve as complementary values characterizing the state of the oxide layer and surface deposits.

 Vosta, J.; Eliasek, J. Quantum chemical evaluation of nitron as a corrosion inhibitor  Werkstoffe und Korrosion (1972), 23(6), 487-9.  

The corrosion inhibition by nitron with mesoionic structure was evaluated by using the LCAO method and studied exptl. for Fe (99.999% pure) in 5% HCl.  The inhibiting efficiency increases with increasing energy of the highest occupied MO due to the decrease of the ionization potential.  Certain positions in the nitron mol. characterized by increased electron d. can thus contribute with their own electrons to the bond formation between inhibitor and metal

Eliasek, J., Kocica, J., Urban, J. Stability of ferrous hydroxide in an aqueous medium Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1972), D25, 5-16.  

Quant. comparison of the effects of various ions on the stability of Fe(OH)2 in an O-free aq. medium at 25° proved that Ni2+, Mn2+, Cu2+, Co2+, and VO3- caused the decompn. of Fe(OH)2 with the formation of magnetite and H.  The effect of these ions decreased in the order Ni2+ > Co2+ > Mn2+ > VO3- > Cu2+.  Consequently, the presence of these ions may favorably influence the formation of a protective magnetite layer on the steel walls of the condensation part of the water-boiling circuits and the low-temp. part of regenerative heating, decrease corrosion of this equipment, and diminish the possibility of formation of deposits giving rise to corrosion in the boiling system.  Since SiO2 inhibits Fe(OH)2 decompn., its complete removal is a necessary requirement.  The Fe(OH)2 stability was unaffected by Zn2+, Sn2+, Al3+, Fe3+, NH4+, and Cr3+, and by WoO42-, MoO42-, SO42-, Cl-, and NO3-.

Talasek, V.,  Mostecky, J.,Vosta, J., Eliasek, J., Matejka, Z. Separation of nonferrous metals from calcium-containing solutions using weak acid or chelating ion exchangers Chemický Průmysl (1972), 22(2), 69-71.  

Mn2+ and Cu2+ can be sepd. from Ca2+-contg. solns. by the carboxylic cation exchanger Amberlite IRC-50 or by the chelating ion exchanger Dowex A-1 at high sp. loads.  The latter resin is advantageously used for systems with small differences in selectivities since the stability of the nonferrous-metals chelates generally differs from that of alk. earths.  The carboxylic resin is applicable for systems characterized by different selectivities of their components.  With respect to the resp. vol. capacity, the carboxylic resin is more suitable for adsorbing Cu and the chelating resin for the sepn. of Mn.  The degree of purity and concn. of Mn and Cu in the eluates from both the tested resins is high enough to justify their further treatment.

Matejka, Z., Talasek, V., Vosta, J., Mostecky, J.,Eliasek, J.,  Singer, P. Regeneration of mixed-bed ion exchangers  (1971), patent CS 140562 19710315.  

Mixed beds, contg. an acid or polyfunctional cation exchanger in H+, Na+, or mixed cycle (Na+, Ca2+, Fe3+), and a basic or polyfunctional anion exchanger in OH-, Cl-, or mixed cycle (Cl-, SO42-, PO43-), are regenerated with aq. 1-20% piperidine or cyclohexyl amine, which converts the cation exchanger into piperidinium or cyclohexylammonium cycle, and the anion exchanger into OH- cycle in a single run without sepg. the resins. The regeneration process is esp. useful for the treatment of industrial condensates and cooling waters.

 Ocenasek, M.,  Pelikan, J., Eliasek, J. Neutralization of acid waste waters from direct cooling of combustion products (1971), patent CS 139660 19710115.  

H2SO3 and H2SO4 contained in flue gas wash water are removed, without salt formation, by the use of an anion exchange bed which is regenerated alternately by an alk. desulfurization soln. contg. NH4OH, (NH4)2SO4, (NH4)2SO3, and (NH4)2CO3.  The effluent from resin regeneration is recycled to water used to absorb S oxides.  Useful ion exchange resins are Dowex 3 and Wofatit L 150.

 Vosta, J.,Talasek, V., Eliasek, J., Rysan, J. Use of spent sulfuric acid from titanium white production as a pickling agent in metallurgy Chemický Průmysl (1971), 21(10), 485-8.  

Fe and Ti compds. contg. dil. H2SO4, as produced in the manuf. of TiO2, can be utilized as a steel pickling agent.  The kinetics of the pickling process was studied with both spent and pure acid used for treating homogenized scale samples and scaled or descaled steel plates.  The kinetic data obtained by chem. analyses of the solns. and by weighing the plates compared well with those based on the potentiometric detn. of corrosion currents.  In spent acid solns. the process of pickling always proceeded more slowly than in pure H2SO4 of the same concn. due to a higher ionic strength in the former; consequently, the most marked differences in the reaction rates were obsd. at the initial stage of pickling.  To attain a pickling efficiency equal to that of 12% pure H2SO4, a spent soln. contg. 15% H2SO4 (65°) must be used.

Vosta, J.; Eliasek, J. Corrosion inhibition from the aspect of quantum chemistry  Corrosion Science (1971), 11(4), 223-9.

Relative to the selection and quant. evaluation of corrosion inhibitors a study was made of quantum-chem. values and inhibition efficiency by using homologous series of pyridine N-oxides with various substituents in the γ-position with quantum-chem. values calcd. by the LCAO method.  Substances studied included those with Me2N, HS, CN, Me, and NO2 substituents.  Polarization curves were measured at 25° in 5% HCl.  Inhibition efficiency depended mostly upon the energy of the highest occupied MO (HOMO), k(1), which is a theoretical analog to the ionization potential of a substance, and the energy of the lowest free MO (LFMO), k(-1), which illustrates the electron affinity of the mol.  Inhibition efficiency increased with increased energy of the HOMO, i.e. with the decrease in the ionization potential so that the mol. acts as an electron donor when blocking the corrosion reaction.  Other values obtained by quantum-chem. calcn. (e.g. electron d., free valences, bond orders) verified these principal concepts.  Inhibitors with higher efficiency have even higher electron d. in the presumed inhibition centers which participate by their own electrons when forming a chem. bond with a metal; electrophilic substitution may take place in a reaction between metal and inhibitor.  Free valence values do not exclude the possibility of a radical reaction.  The most active site of the compds. assessed was the O in the N-O and S-O groups due to its min. at. localization energy and high values of electrophilic and radical superdelocalizability on the O atom.

Talasek, V.; Eliasek, J.; Smetak, V. Kinetics of the ion exchange.  VII.  Systems Cl-SO4-OH on strong basic anion exchangers Collection of Czechoslovak Chemical Communications (1971), 36(6), 2347-51.

The differential kinetic, transport, and equil. measurements were carried out in the systems Cl-SO4-OH and Cl-SO4 in the range of gel diffusion and of film diffusion on Dowex 1X8 and Lewatit MP-500.  The following topics were investigated: the change of the rate of diffusion with the compn. of the exchanger phase and with the direction of the exchange, the effect of the selectivity changes and of the water transport on the exchange kinetics.

Panacek, F. Kocica, J. Eliasek, J. Evaluation of an oxide layer on the boiler tubes of steam generators  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1970), D 20, 35-48.  

Measurements of the layer thickness, corrosion resistance, and equil. corrosion streams were carried out to evaluate the properties of the oxide layer on the inner walls of boiler tubes of steam generators.  The apparent thickness of the layer was detd.  The values obtained were compared with those obtained by measuring the magnetic layers formed in exptl. tubes under the defined conditions.  The exptl. samples of the industrial tubes were obtained from 2 different locations and 2 different types of steam generators.  The values obtained were characteristic, to a certain degree, for the oxide layer formed but were affected by the nonhomogeneous character of the layers, esp. by the presence of Cu and its compds. and by surface deposits.

Vosta, J. Eliasek, J.,Janda, M. New corrosion inhibitors  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1970), D 20, 23-33.  

The evaluation of boiler steel corrosion inhibitors by means of polarization curves and polarization resistance was studied.  Nitrone and some thiophene derivs. are very good corrosion inhibitors in a HCl medium.  Esp. nitrone which belongs among the mesoionic group of compds., proved to be the most efficient of them.  8,9-Dihydrothionaphthene dioxide was chosen because of its resemblance to dibenzyl sulfoxide in regard to S-O groups.  2-Aminopyridine was subjected to measurements in order to obtain some primary information on the behavior of this substance as corrosion inhibitor in a HCl medium.

Eliasek, J., Kocica, J., Chabica, Z. Solubility of iron oxide in etching solutions  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1970), D 20, 5-21.  

The soly. of oxide and hydrated Fe oxide in etching solns. at 60° and the of their solns. were detd.  The oxide contg. Fe3+ ions dissolved more rapidly in HCl than in complexon III.  The opposite was found for Fe2+ oxide.  The dissoln. in H2SO4 was 30% slower than in HCl and the dissoln. rate in citric acid was very low.  The addn. of 5 mM HF to 0.5M HCl increased rate of Fe3O4 dissoln. by a factor of 10 the addn. of 20 mM by a factor of 100.  HF gave the same results when added to complexon III.

Talasek, V., Hala, S., Kuras, M., Eliasek, J. Coulometric determination of 1-aminoadamantane hydrochloride in dilute aqueous solutions Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1969), 16, 85-8.  

1-Aminoadamantane hydrochloride was detd. in dil. aq. solns. by coulometry with Br in a buffered medium (pH 8).  By application of a suitable generation flow of Br, it was possible to det. 0.5 μmole/l. with convenient accuracy.

Talasek, V., Eliasek, J. Kinetics of ion exchange.  VII.  Measurements in the film diffusion region  Collection of Czechoslovak Chemical Communications (1971), 36(1), 77-83.  

From the oscillometrically measured exchange half-times the film diffusion data were calcd. of 17 cations and of 12 org. bases on Dowex 50WX16 with respect to the H+ ion, as well as data of 17 anions and of 7 org. acids on Dowex 1-X8 with respect to the OH- ion, the total concn. of external soln. being 5 × 10-3N.  Integral kinetic data may be interpreted by means of the Nernst-Planck equation or transport coeffs. in ternary systems.  The kinetics in the film diffusion region is primarily dependent on the valency of the ion, its mobility, hydration, and steric arrangement.  The selectivity changes during unidirectional integral diffusion are not so significant as in the both-way, particularly differential, kinetic measurements.

Panacek, F., Kocica, J., Eliasek, J. Physicochemical processes in boiler tubes.  II  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1969), 18, 5-14.  

The comparison of magnetite protective layers prepd. on the chem. cleaned surfaces of boiler tubes in processes using neutral, distd., and thermally de-aerated water in a flow app. in an autoclave and in an elec. furnace was studied.  The protective layers were prepd. at temps. 210, 250, 275, and 300° during 24 hr.  With increasing temp., the corrosion protection and the apparent d. increased.  The protective layer was more porous under stabilized through flow conditions than under stationary conditions.

Vosta, J.,  Talasek, V., Ocenasek, M., Eliasek, J., Volak, J. Use of piperidine as a volatile alkalization agent Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1969), 18, 15-28.  

Piperidine was used as a volatile alkalization agent and corrosion inhibitor in a high-pressure steam-water circuit. Piperidine is of sufficiently basic character, which makes it possible to decrease P2O5 content in boiler water to the 3 mg/l. level.  It achieved a 70-80% decrease of Fe level in the system, and is inactive with respect to Cu. In the H-form of strongly acid cation exchangers piperidine is quant. sorbed as piperidinium cation and regeneration of exchanger is quite possible.

 Jungvirt, A., Eliasek, J. Sulfur balance in waste gases of steam generators Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1969), 18, 49-57.  

The S balances in stations using fuels of various calorific values and different S content were compared.  Also, the effects of elemental, pyritic, and sulfate S in fuels, and effects of very fine grinding, the air excess, and the type of furnace on the degree of SO2 conversion to H2SO4 were studied.  Some anal. methods for detns. under production conditions are evaluated.  The H2SO4 content in waste gases increased with the increasing amt. of sulfates in fuels.

Mostecky, J., Eliasek, J., Singer, P., Talasek, V., Vosta, J. Protective agent for steam ducts in power engineering plants (1969), patent CS 133224 19690715.  

Mixts. of 1 part C18H37NH2 (I) and 0.01-1 part emulsifier are added at a rate 0.01-10 g agent/ton steam or 10-1000 g agent/ton feed water after the demineralization process.  Alkane- and arenesulfonyl chlorides, sulfosuccinates, and condensation products of fatty acids with ethylene oxide are suitable emulsifiers.  I forms in the ducts a protective lining which prevents the effect of corrosive media and blocks starting corrosion reactions on microcathodes and anodes.

Talasek, V., Vosta, J., Matejka, Z., Eliasek, J., Mostecky, J., Singer, P. Treatment of condensate in power engineering installations (1969), patent CS 133232 19690715.  

Cation-exchanger beds in the piperidinium from have a very low selectivity coeff. for the piperidinium cation when the cation exchanger is in a neutral medium.  In combination with simultaneous alkalization of the feed-water with piperidine, there is provided quant. trapping of all metal ions that have gotten into the condensate by leakage or corrosion.

Vosta, ., Talasek, V., Eliasek, J. Inhibitor of atmospheric corrosion (1969), patent CS 133138 19690715.  

Combinations of 1 part piperidine nitrite (I) and 0.5-1 part volatile alk. agent show a synergistic effect.  The volatile compd. (NH3, cyclohexylamine, N2H4, piperidine, morpholine) blocks the initial corrosion process and initiates the evapn. of I, which affords a long-lasting protection.  The combination in concns. of 0.5-2 g/m2 Fe or Cu surface gives 80-100% protection for 100-200 days at 80% relative humidity.

Pelikan, J., Ocenasek, M., Eliasek, J. Apparatus for the determination of capacity of ion exchangers for the removal of dissolved oxygen from water  (1969), patent CS 131203 19690215.  

Water is satd. with O produced electrolytically with a known quantity of elec. current.  Satd. water is passed through a column of ion exchanger and the decrease in the O content, removed by the ion exchanger, detd. by means of a thermally conductive cell which has the measuring filaments connected in a Whe atstone bridge. The app. excludes the influence of atm. O, does not require involved batching of O, and laborious anal. methods.

 Talasek, V., Eliasek, J. Kinetics of ion exchange.  IV.  Anion exchange of organic acids on Dowex 1  Collection of Czechoslovak Chemical Communications (1969), 34(9), 2538-44.  

Diffusion data calcd. from oscillometric values shed light on the kinetics of the exchange of org. acids in the gel diffusion region on a strongly basic polymd. anion-exchange resin, Dowex 1, 20-50 mesh, which is doubly cross-linked in many ionic forms of the anion exchange resin.  The formate, acetate, oxalate, malonate, lactate, tartrate, citrate, Na2EDTA, salicylate, and terephthalate anions were investigated.  Dowex 1-X4 and 1-X8 were studied in the following forms: OH-, F-, Cl-, Br-, and SO42-.  The diffusion coeff. was calcd. from the relation Dr = (1/4)(R/π)2(1/t1/2), where R is the mean radius of the ion-exchange resin bead and t1/2 is the exchange half-time of the given ion, which was detd. graphically.  The conditions of gel diffusion for the studied compds. are guaranteed, if the concn. of the external soln. is higher than 0.05M.  Depending on the structure of the org. mol. the rates of diffusion are affected both by the kind as well as valency of the counterions which influence swelling of the anion-exchange resin, and by the degree of cross-linking of the resin.  The rate of diffusion decreases with increasing size of the org. mol., and unlike inorg. anion-exchange resins, is independent of valency.

 Mostecky, J., Eliasek, J., Talasek, V.,Vota, J., Singer, P. Emulsion mixture for protection of steam-water circuits of energy installations against corrosive attack and process for its application (1969),patent DE 1816905 19690731.  

Corrosion in steam power and heating plants is prevented by addn. to the process water of 0.01 to 10 g./ton active ingredient of an emulsion consisting of 1 part by wt. higher aliphatic amine (primary, secondary, or tertiary) and 0.01 to 1.0 part by wt. emulsifier.  Preferred amines are octadecylamine, laurylamine, hexadecylamine, and dioctadecylamine.  Preferred emulsifiers are ethoxidized fatty acid, alkylpolyglycol ether, saccharose monostearate and polyethylene glycol 1500.  For the prevention of crevice corrosion 0.01 part by wt. ZnSO4 and 0.01 part by wt. P2O5 equiv. can be added.  Greater effectiveness over previous amine systems is claimed.

 Eliasek, J., Talasek, V. Kinetics of ion exchange.  III.  Exchange of the type X-OH on Dowex 1 and on type II Amberlite IRA  Collection of Czechoslovak Chemical Communications (1968), 33(11), 3866-70.  

The exchange kinetics of 16 inorg. anions on Dowex 1-X4, Dowex 1-X8, Amberlite IRA-400(I), IRA-402(I), and IRA-410(II) was measured oscillometrically and the half-times and diffusion coeffs. were computed.  The exchange rate is inversely proportional to the degree of cross-linking of the exchanger.  Of univalent anions, the halides exhibit the highest exchange rate.  The rate of exchange decreases markedly with the valency of simple anions; with complex anions the effect is a reversed one: [Fe(CN)6]3-exchanges more slowly than does [Fe(CN)6)4-.  The rate of exchange increases with the basicity of the exchanger.  The effect of the porosity of the anion exchanger on the kinetics of the exchange is a slight one.

Talasek, V., Eliasek, J. Kinetics of ion exchange.  II.  Exchange of the B-H type in a series of organic bases on Dowex 50W Collection of Czechoslovak Chemical Communications (1968), 33(11), 3618-24.  

The kinetics was measured of the uni-univalent exchange process of a series of 14 org. bases in aq. solns. on strong acid cation exchanger Dowex 50W in the H form under conditions of the gel kinetics.  The effects were studied of the degree of crosslinking and of the size of the exchanger particles, and of the steric properties of bases on the rate of exchange.  The exchange kinetics of org. bases depends primarily on the steric nature of the substituent and on the degree of cross-linking of the exchanger.  The exchange rate of condensed, conjugated mols. is lower than that of the quaternary bases of greater dimensions with the same no. of aromatic substituents, esp. at lower degrees of cross-linking and smaller particle sizes of the exchanger.  The exchange rates of org. bases in aq. solns. are slower than those of metallic ions.

Talasek, V., Eliasek, J. Coulometric bromination of extremely diluted aqueous solutions of some primary and secondary amines, amino alcohols, and diamines  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1967), 15, 5-14.

Coulometric titrn. was applied to the detn. of up to 5% of an individual primary and secondary aliphatic and naphthenic amines, diamines, amino alcs., and C1-18 arylalkylamines in aq. soln.  The detn. is based on substitution of H in the primary or secondary amine group with Br continuously evolved from a soln. of Br-.  The test soln. was adjusted to pH 8 with a buffer.  The presence of free Br in the soln. can be considered only at pH ≤6.  The bromination of tertiary amines is impossible as they do not contain the H necessary for the substitution.  This method does not distinguish between individual amines of the same group, or between primary and secondary amines.  The coulometric titrn. curves had sufficient slope at a generating current of approx. 2 ma. and a polarization voltage of 300 mv.  In the case of equimolar concns., the titrn. times in the series diamines, primary amines, amino alcs., secondary amines were in the ratio 4:2:1.  The max. error did not exceed 0.5%. NH3, aromatic amines, and aromatic compds. interfere.  If NH3 was present in a sample contg. a primary aliphatic amine, the sum of both components was detd. coulometrically. NH3 was detd. spectrophotometrically in a sep. sample, and the amine was detd. by difference.  Tertiary amines and PhNO2 do not interfere.

Eliasek, J., Talasek, V. Kinetics of the ion exchange.  I.  Exchange of the type M-H on Dowex 50W Collection of Czechoslovak Chemical Communications (1968), 33(5), 1501-7.  

The cond. changes of solns. of the metallic salts owing to the release of the H+ ions from the ion exchanger were measured oscillometrically.  From the results, the diffusion coeffs. of intraparticle diffusion of 23 cations of various valency were calcd.  The effects of the particle size and of the degree of cross-linking on the exchange rate was investigated.  With the Dowex 50W of 100/200 mesh, the diffusion coeffs. change very little both with the degree of cross-linking of the ion exchanger and with the valency of the cation.  On the other hand, with the Dowex 50W of 20/50 mesh, these changes are significant.  With the Dowex 50W-X16, the diffusion coeffs. decrease by about one order of magnitude, if the valency of the cation increases by one unit.  With the Dowex 50W-X8, the diffusion coeffs. of univalent, divalent, and trivalent cations are of the same order of magnitude.  Oscillometry is applicable, esp. in cases of very rapid ion exchange.  The method is simple and eliminates the troubles with the anal. detn. of some ions.

 Panacek, F., Kocica, J., Eliasek, J. Physicochemical processes in stea, boiler tubes.  I Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1967), 15, 53-69.  

The protective-layer formation on the inside wall of a pickled boiler tube was studied using neutral, thermally degasified, distd. H2O.  The formation was followed as a function of time, thermal load, and temp. of the inside wall of the boiler tube.  Expts. showed that time consumed by protective-layer formation after boiler pickling becomes shorter with increasing temp.  At 220° it varied 24 hrs.

Talasek, V., Vosta, J., Eliasek, J. Coulometric determination of ion concentrations of piperidine in aqueou solution in the presence of ammonia  Fresenius' Zeitschrift fuer Analytische Chemie (1967), 230(1), 29-33.  

A method for the detn. of low concn. of piperidine in aq. solns. and in the presence of NH3 is described.  To a 5-70 ml. sample was added M NaBr soln. and a soln. buffered at pH 8 contg. 1 part 0.33M KH2PO4 and 19 parts 0.33M Na2HPO4, so that the final minimal concns. were 0.1M Br- and 0.02M buffer.  The Br- reacts quant. with the piperidine to substitute H on N.  The excess Br- is then coulometrically titrated to det. indirectly the amt. of piperidine present in the sample.  In the presence of NH3, the sum of piperidine and NH3 is detd. coulometrically after similar treatment with Br-, and NH3 is then sep. detd. according to Nessler's photometric method.  The piperidine content results from the difference.  Piperidine concns. 3 detn.

Eliasek, J.,Jungwirt, A. Break-point chlorination of some phenols  Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, F:  Technologie Vody (1966), No. 10, 49-56.  

The chlorination of phenol follows a substitution mechanism to the formation of trichlorophenol.  The Cl in the para position is hydrolyzed off and chloroquinone formed by simultaneous oxidn. with HOCl.  Further chlorination of chloroquinone proceeds again through the substitution of the H with Cl.  Light causes the transformation of chloroquinones into hydroxychloroquinones which are not stable at pH >7 and are polymd. to compds. of the humic acid type.  The reaction mechanism for o-cresol is analogous.  Pyrocatechol also yields humic acid type substances but undergoes simultaneous decompn., owing to the ease of oxidn.

Prochazka, J., Sich, J., Eliasek, J. Influence on the conductivity values during mixed-bed tests   Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1966), 10, 45-52.  

The effects of penetrating inorg. cations, the size of the tested mixed-bed, and the properties of the ion exchangers on the elec. cond. of treated water were studied.  Differences in the elec. cond. for various types of ion-exchange resins were caused by the sp. differences in porosity.  The anomalies of the elec. cond. were caused mainly by the pos. charged ion-exchange resin, the function of which was influenced by the sorption of org. compds. on a strongly basic ion-exchange resin.

Vosta, J., Talasek, V., Ocenasek, M., Eliasek, J., Dluhos, J. Piperidine, a new volatile alkalizing agent Mitteilungen der Vereinigung der Grosskesselbesitzer (1967), No. 106, 39-41.  

Piperidine is effective in concns. of 2 mg./l. in the alkali treatment and softening of boiler water and its use enables the phosphate concn. to be lowered to 3 mg. of P2O5/l.  It also protects the boiler against corrosion.

Eliasek, J.,Talasek, V. Use and analysis of volatile alkalizing agents Sbornik Vysoke Skoly Chemicko-Technologicke v Praze, D:  Technologie Paliv (1966), 10, 13-26.

Cyclohexylamine, morpholine, N2H4, NH3, and octadecylamine were tested as alkalizing agents for circulating water in elec. works.  The sepg. coeff. and basicity were used as criterion.  A pH of 9 was used.  NH3 and cyclohexylamine were found to be most suitable.  The only disadvantage of NH3 was corrosion of the Cu app.  The use of cyclohexylamine and morpholine was limited by the temp. of the thermal dissocn. at which NH3 was prepd.  The results showed that in the alk. circulating water, with the exception of alkalizing with NH3, two components were always present: NH3 and the undissocd. volatile alkalizing agent.  Coulometric titrn. with Br was used for the analysis. NH3, cyclohexylamine, and morpholine were analyzed in buffered solns. at pH 8.  In the case of 2 components, the use of coulometry was convenient only for detn. of NH3 in the presence of hydrazine, because hydrazine is detd. in an acidic medium.  In other cases only the sum of NH3 with the other component was detd.  Combination with the photometric method was convenient.  For the detn. of the mixt. NH3-morpholine, morpholine was detd. photometrically with CS2, which yielded a yellow-colored Cu complex of the morpholinecarbodithioic acid.  For the detn. of the mixt. NH3-cyclohexylamine, NH3 was detd. as indophenol, which in the alk. medium dissoc. to give a blue color.

Eliasek, J.; Talasek, V.; Kucera, Z. Determination of volatile alkalization agents  Mitteilungen der Vereinigung der Grosskesselbesitzer (1965), No. 96, 174-6.  

Morpholine, cyclohexylamine, and NH3 in the water-steam cycle in power plants are detd. by coulometric titration with Br at pH 8 with a generation current of about 2 ma. and a polarization potential of 300 mv. more Fe2+ does not interfere.  To det. hydrazine, use a soln. in 0.3N HCl. Hydrazine can thus be detd. in the presence of NH3, for NH3 does not react in this acid medium.  To det. NH3 in the presence of morpholine, titrate both coulometrically at pH 8.  Det. morpholine alone by conversion to the dithiocarbamate with CS2, extn. of the yellow Cu complex with CHCl3, and photometric measurement.  To det. NH3 (0.2-2 mg./1.) in the presence of cyclohexylamine (≤2 mg./l.), titrate both coulometrically at pH 8. Det.  NH3 photometrically as indophenol at 610-40 mμ following the method of Bolleter (B., et al., CA 55, 12151b).  Keep the pH at 9.9-10 with a borate buffer, and keep time and temp. const. before alkalization.

Eliasek, J., Brodsky, A., Cech, J., Richterova, V. Determination of chemical oxygen demand [C.O.D.] by permanganate methods  Sb. Vysoke Skoly Chem.-Technol., Praze, Oddil. Fak. Technol. Paliv Vody (1960), 4(1), 179-98.  

Several methods were compared for detg. C.O.D. with KMnO4.  The techniques studied included the method of Kubel, the ASTM method, the German DEV and Schulze methods, and the Russian standard method as described by Meissner.  The C.O.D. detns. were made on river water samples dild. to a C.O.D. of 1-5 mg./1, and on lab.-prepd. solns. of sucrose, phenol, o-cresol, pyrocatechol, alkali lignin, and humic acid.  The effects of the time of heating, concn. of H2SO4, excess permanganate, and diln. of the sample on the values obtained were evaluated.  The results of a large no. of detns. were analyzed statistically.  The accuracy of all methods can be considered as equivalent.  Oxidn. in an alk. medium (the Schulze method) has the advantage of eliminating the error caused by the presence of chloride ions.  However, if the sample has a high content of ammonium salts, detns. should be clone in an acidic medium.  An excess of H2SO4 causes an increase of the values obtained in blank detns.  Within the usual range of concn., the effects of permanganate excess and sample diln. compensate each other.  Recently, the permanganate method is being replaced by other oxidn. methods in several countries on the grounds that certain org. compds. are not detected by permanganate oxidn.  However, the simplicity of the permanganate method, its good reproducibility, and relatively high accuracy make it a valuable anal. tool, particularly for the control of industrial wastes, where the important aspect is a comparison of the relative C.O.D. values of samples of the same type.  16 references.

Eliasek, J.; Jungwirt, A. The mechanism of phenol chlorination in aqueous solutions Collection of Czechoslovak Chemical Communications (1963), 28, 2163-70.  

In acidic aq. soln. at pH 2-3, chloroquinones are formed by chlorination of phenol and o-cresol.  The no. of substituted H atoms increases with increasing concn. of Cl.  At pH 7.5 at the Cl concn. corresponding to the break point or greater, disintegration of phenol, o-cresol, and pyrocatechol, and in the same time photo-disproportionation of chloroquinones (I) to hydroxychloroquinones (II) takes place; II polymerize readily to humin-like substances.  The disintegration is greatest with pyrocatechol, reaching 60%.  I and II are detd. polarographically and by paper chromatography.  Tables of E1/2 and Rf values are given.

Landa, S., Eliasek, J. Biological degradation of bivalent phenols Sb. Vysoke Skoly Chem.-Technol. Praze, Oddil Fak. Technol. Paliv Vody (1959, 3(No. 1), 35-53.  

The biochem. production of muconic acid (I) is one of the ways of utilizing catechol (II) contained in phenolic wastes from low-temp. carbonization.  Expts. were made to achieve the highest possible rate of degradation and highest possible yields of I.  The effect of toxic substances, especially SCN-, S--, and CN-, on the course of degradation using a standard medium inoculated with a mold of the genus Oospora were tested.  The compn. of the standard medium was: 1800 mg. KH2PO4, 100 mg. (NH4)2SO4, 250 mg. MgSO4.7H2O, and 2000 mg. II in 1 l. of H2O.  pH of this soln. was 5.6-5.8.  NH4SCN and KSCN accelerated the degradation process depending on the NH4+ and K+ present, even at considerably high concns.  The SCN- content did not change during the degradation.  The amt. of I formed was substantially smaller at a higher NH4+ content, whereas in the presence of a larger amt. of K+ salts it did not change.  S-- decreased the rate of degradation and the yields of I at a concn. higher than 125 mg. S--/l.  KCN at a concn. above 40 mg./l. strongly decreased the rate of degradation as well as the yields of I.  The stimulative effect of small amts. of MnCl2, NiSO4, Co(NO3)2, and K3Fe(CN)6 was not observed.  Expts. were made in which ground magnesite was added to the soln. in the amt. of 500 mg./l. to maintain pH of the soln. at an optimum level.  During the degradation the pH of the soln. did not fall below 4.0.  The degradation was more rapid and the yield of I substantially higher (280 mg./l.).  I did not occur in the degradation of resorcinol.

 Karas, F.; Eliasek, J.; Palaty, V. Rapid method for the determination of sulfates Voda (1958), 37, 316-17.  

A modification of the use of thoron [1-(o-arsonophenylazo)-2-naphthol-3:6-disulphonic acid] as metallochromic indicator (Fritz and Yamamura, CA 49, 15631d) is described.  Procedure: Pass the sample contg. dissolved sulfate through a cation-exchange column (Wofatit KPS-200), discard the 1st 10 ml. of the eluate, and to another 10-25 ml. add HClO4 or NaOH until the pH is 3-5 and iso-PrOH in excess; add indicator soln. (0.2% aq. soln.) (2-4 drops) and titrate the yellow soln. with 0.01 to 0.05N Ba(ClO4)2 (in 80% iso-PrOH) until pink.  The method yields good results for the detn. of sulfates in H2O, fuels, or coal (after combustion and oxidn.) and in biol. materials.

Landa, S.,Eliasek, J. Biological degradation of phenols. III. Intermediates in the biological oxidation of catechol with O.ovrddot.ospora Collection of Czechoslovak Chemical Communications (1957), 22, 1029-35.  

Landa, S., Eliasek, J. Biological degradation of phenols. III. Intermediates in the biological oxidation of catechol with O.ovrddot.ospora Chemické Listy pro Vědu a Průmysl (1956), 50, 1834-9.

C.A. 48, 4043g.  The course of biol. degradation of catechol (1) with O.ovrddot.ospora is controlled by initial concn. of I and by pH whose optimum is 4-6.  Concn. of the intermediate cis-cis-muconic acid (II), reaches its max. just before complete consumption of I.  Further contact with the medium transforms II to CO2HCH2CHCH:CHCOO (III), OCOCH2CHCHCH2COO (IV), and CO2HCH2CH2COCH2CO2H (V).  Paper chromatography revealed the presence of (CO2H)2, CH2(CO2H)2, (CO2HCH2)2, CO2HCH2CH(OH)CO2H, CO2HCH(OH)CH(OH)CO2H, citric acid, III and V.  IV was formed during isolation process.  Degradation of 877 g. I gave at 40°, pH 5-6, concn. 3 g. I/l. 23 g. II, m. 189-90°, 2.4 g. IV, m. 128-9°, and 1.2 g. III, m. 110-11°.

Maly, A., Eliasek, J. Identification of organic acids by distribution chromatography on paper Průmysl Potravin (1955), 6, 138-40.

The less volatile org. acids were detd. by means of the ascending, descending, and circular method in various systems of solvents.  The distn. products of wood contained the following acids: oxalic (I), tartaric (II), malic (III), succinic (IV), glutaric, and a considerable amt. of pyruvic.  Products of biol. decompn. of catechol contained besides I-IV, citric, malonic, and β-oxoadipic acids, and γ-carboxymethyl-Δα-butenolide.

Eliasek, J. Estimation of phenols Paliva (1954), 34, 45-51.  

Methods were evaluated for the estn. of phenols in phenolic waters or tar carbonization, namely: bromometric, iodometric, and colorimetric.  156 references.


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