Briefs - "Naphthalene Via Hydrodealkylation Comparison of Pilot and

analog computer. A mathematical model was developed based on available kinetic data and on pilot plant results in which commercial plant charge stocks...
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BRIEFS 1NORGANIC ION EXCHANGE SEPARATION OF CESIUM FROM PUREX-TYPE HIGH-LEVEL RADIOACTIVE WASTES

A flowsheet is presented which includes cesium loading, sodium removal with oxalic acid, water wash, and acid removal with ",OH, all at low temperatures, and elution with 2M (NH4)zCOa a t elevated temperature. The clinoptilolite column can be re-used with bed make-up of about 2% per cycle. A relatively pure (Cs)2C03 solution is obtained by volatilization of the (NH4)tCOa from the eluate. Data on the effects of varied flow rate, temperature, waste dilution, exchanger particle size, and cesium concentration are given. Flowsheet is adaptable to removal of small amounts of cesium from various solutions high in salts or acid. Jack L. Nelson, George J . Alkire, and Basil W. Mercer, Hanford Atomic Products Ojeration, General Electric Go., Richland, Wash. IND.ENG.CHEXPROCESS DESIGN DEVELOP. 3,143-148 (1964) KINETICS OF THE COPPER-FERRIC CHLORIDE REACTION AND THE EFFECTS OF CERTAIN INHIBITORS

The reaction of ferric chloride solution with copper metal is basic to the production of copper photoengraving plates. Economical operation of this process and optimum quality of the product can be achieved only through application of certain inhibitors coupled with control of the many process variables. The rate of this heterogeneous reaction is here related to temperature, solution molarity, direction of flow, viscosity of solution, and presence of dissolved oxygen. Temperature coefficients, Arrhenius activation energies, reaction rate, flow rate dependence, and sample position dependence of the reaction rate all support the proposition that the reaction is diffusion-controlled. The relative reactivities of the various ion species present are identified. Effects of thiourea, ethylenethiourea, and formamidine disulfide as inhibitors were studied as functions of temperature, concentration, and flow rate. Substantial contributions to the efficiency and economy of the photoengraving process are related to these studies.

W. H. Burrows, C. T . Lewis, J r . , D . E. Saire, and R. E. Brooks, Georgia Institute of Technology, Atlanta, Ga. IND.ENG.CHEM.PROCESS DESIGN DEVELOP. 3,149-159 (1964) ADSORPTION OF GASES O N RANEY NICKEL

Chemisorption of carbon monoxide and carbon dioxide on Raney nickel was studied by the conventional constant volume, variablepressure technique. The results obtained were in only partial agreement with those reported by others. The quantity of carbon monoxide chemisorbed was very much dependent upon the aluminum leaching procedure, the exact composition of the initial nickel-aluminum alloy, the time and manner of storage, and the thermal pretreatment of the Raney nickel. Significant chemisorption ofcarbon dioxide was observed, as expected.

James H u f , Raymond Jasinski, and R. Parthasarathy, Research Division, Allis-Chalmers Manufacturing Go ., Milwaukee, W i s . IND.ENG.CHEM.PROCESS DESIGN DEVELOP. 3,159-164 (1764) SULFOCHLORINATION OF CYCLOHEXANE INDUCED BY GAMMA RADIATION

The possibility of utilizing gamma radiation for initiating direct sulfochlorination of hydrocarbons was studied. Liquid cyclohexane reacted with SO2 and Clz in the presence of gamma radiation to give very high yields of cyclohexanesulfonyl chloride and some chlorocyclohexane and cyclohexanedisulfonyl chloride. Reaction rates were determined as a function of dose rate. The selectivity of the reaction and the degree of conversion were determined as a function of temperature, gamma radiation intensity, and SO2/C12 ratio. A reaction mechanism was proposed for this chain reaction. A basic plant design is developed for the continuous sulfochlorination of cyclohexane initiated by gamma radiation. The economics of such processes may become attractive with the expected availability of cheap radiation sources.

AEfred Schneider and J u Chin Chu, Polytechnic Institute of Btooklyn. Brooklyn, N . Y .

IND. ENG.CHEM.PROCESS DESIGN DEVELOP. 3,164-169 (1964)

CATALYTIC SYNTHESIS OF ACRYLIC ACID AND ETHYL ACRYLATE FROM ACETYLENE, CARBON MONOXIDE, AND WATER OR ETHANOL UNDER PRESSURE

An exhaustive and intensive study has been made of the direct syntheses of acrylic acid and ethyl acrylate from acetylene, carbon monoxide, and water or ethanol at high pressure using salts of iron, cobalt, and nickel as catalysts. Nickel iodide is the most active catalyst for the synthesis of ethyl acrylate and nickel naphthenate for acrylic acid. Cobalt carbonyl has no catalytic activity. Under optimum conditions the conversion of acetylene to ethyl acrylate was 61 .37& using nickel iodide-silica gel catalyst, and that of acrylic acid was 14.2%) using nickel naphthenate catalyst. Decomposition studies of the reactants and the products were done to explain the formation of various by-products. S. K. Bhattacharyya and A . K. Sen, Indian Institute o j Technology, Khara,gjur, India IND.ENG.CHEM.PROCESS DESIGN DEVELOP. 3,169-176 (1764) NAPHTHALENE VIA HYDRODEALKYLATION. COMPARISON OF PILOT AND COMMERCIAL PLANT DATA WITH AN ANALOG COMPUTER MODEL

Production of naphthalene via hydrodealkylation in an adiabatic tubular reactor was simulated using an analog computer. A mathematical model was developed based on available kinetic data and on pilot plant results in which commercial plant charge stocks were used. Fifteen separate reactions were included in the final model to describe the hydrodealkylation of commercial charge stock. Coefficients in some of the kinetic equations were established by parameter estimation techniques using an analog computer. The model was used to predict temperature distributions and reactor effluent concentrations for a commercial plant in which unreacted product was recycled to the feed. The effects of reactor inlet temperature, hydrogen purity, and gas-oil ratio on plant operation were studied. Predictions of plant performance by use of the model agreed wirh plant operating experience. C. R. Andersson, and D. E. Lamb, University of Delaware, Newark, Del. IND.ENG.CHEM.PROCESS DESIGN DEVELOP. 3, 177-1 82 (1964) IMPROVEMENT OF IRON BLEACHING IN CLAYS THROUGH POTENTIOMETRIC CONTROL OF SODIUM DlTHlONlTE ADDITION

By the use of platinum-calomel electrode data, the reduction of iron contaminants in clays with acid-dithionite solutions has been followed in detail. More precise information has been obtained about clay processing, the dithionite decomposition reaction, the Fe+3 reduction, and the reaction with atmospheric oxygen. Theoretical calculations are given for new techniques in the bleaching operation. Efficiency improvemenu of the order of 100% are feasible in high dithionite concentrations. R. F. Conley, H. J . Golding, and M . W. Taranto, Georgia Kaolin Research Laboratories., Elizabeth, N . J . IND.ENG.CHEM.PROCESS DESIGN DEVELOP. 3,183-188 (1964) PRODUCTION OF HIGH PURITY CHROMIUM OXIDE AND RECOVERY OF CHLORINE FROM HYDROGEN CHLORIDE

A process is proposed for producing high purity chromium oxide from low grade chromium trioxide while providing means of simultaneous chlorine recovery. Chromyl chloride, used as an intermediate, is formed from chromium trioxide and hydrogen chloride and is decomposed, after purification, to high purity chromium( IV) oxide and chlorine. The technical feasibility of the process is examined, using data from the literature, and the economic conditions are outlined under which the process would be feasible. Neither the chemical and engineering factors nor the economic factors are unfavorable. R. L. Hamilton, Oklahoma University, Norman, Okla. IND.ENG.CHEM.PROCESS DESIGN DEVELOP. 3,188-190 (1764) CORRESPONDENCE. EFFECT OF GAS RATE O N OVER-ALL MASS TRANSFER COEFFICIENTS AND THE PERFECT MIXING THEORY

Comments on a recent article by R. H. Buchanan, D. R. Teplitzky, and Djoeriaman Oedjoe [IND. ENG. CHEM. PROCESSDESIGN 2, 173 (1964)]. DEVELOP. R. G . Robinson, T h e Pennsylvania State Uniuersaty, UniverJity Park, Pa. TND. ENG.CHEM.PROCESS DESIGN DEVELOP. 3,191-192 (1964) VOL. 5 6

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