摘要:

AbstractOxides of nitrogen are present in the effluent gases from nitric acid and nylon intermediates plants and if released in sufficient quantity they could be objectionable owing to their intensive reddish‐brown color and to their corrosive and poisonous nature. A paper study showed that the oxides of nitrogen could be reduced by absorption in an alkaline solution. Based on pilot plant tests, a large fume abatement unit was designed, installed, and operated in a satisfactory manner to reduce the concentration of the oxides of nitrogen. In 1956, the color of the combined effluent gases was practically eliminated when a more economic waste ammonia‐caustic liquor replaced the dilute caustic scrubbing solution and finely dispersed ammonium salts were removed in a Venturi scrubber. The method may be used to eliminate the objectionable brownish‐red color of effluent gases leaving a nitric acid

ISSN:0008-4034    

DOI:10.1002/cjce.5450360101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1958

数据来源: WILEY

摘要:

AbstractHeat transfer data have been obtained for heat flowing from a steam jacketed column to a packed, fluidized and spouted bed. The data for packed and fluidized beds are compared with generalized correlations previously proposed. In the case of spouted beds, the heat transfer coefficient increases sharply at the onset of spouting and passes through a maximum as the gas velocity is increased. The maximum heat transfer coefficient is from 25–75% lower for a spouted bed than for a fluidized bed under similar flow conditions. Rice, wheat and Ottawa sand were used as bed material

ISSN:0008-4034    

DOI:10.1002/cjce.5450360102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1958

数据来源: WILEY

摘要:

AbstractExtractive distillation is widely used in separating C4hydrocarbons. A typical extractive solvent for such a separation is an acetone‐water mixture. Correct design and selection of optimum operating conditions for extractive distillation towers are ensured by a knowledge of the vapor‐liquid equilibria involved.Pseudo‐binary systems of each of the C4hydrocarbons, n‐butane, isobutane, butene‐1, and cis‐butene‐2, and acetone‐water solvent were investigated at temperatures of 100°, 150°, and 200°F., at water concentrations of 5, 11, and 17 wt. %, (C4hydrocarbon‐free) and at hydrocarbon concentrations up to 28 mole %. The results were interpreted as activity coefficients, and showed good consistency. The binary Margules three‐suffix and van Laar two‐suffix equations correlate the measured activity coefficients adequately as a function of concentration.Dependence of activity coefficients on temperature was used to evaluate the differential heats of solution of the hydrocarbons in the acetone‐water solvent. The results were also used to derive partial liquid enthalpy‐concentration curves.Ternary Margules three‐suffix and van Laar two‐suffix equations gave a satisfactory correlation of activity coefficients for pseudo‐ternary systems. The ternary Margules equations were used to calculate relative volatilities, which are presented graphically as functi

ISSN:0008-4034    

DOI:10.1002/cjce.5450360103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1958

数据来源: WILEY

摘要:

AbstractA new method of leaching low‐grade manganese ore (<5% Mn) utilizing pyrite as a reagent was developed. By heating an aerated slurry of ore and pyrite and by recycling the leach liquor at controlled acidity to attack fresh ore, a manganous sulphate solution free of iron was obtained which when heated to about 175°C., yielded manganous sulphate monohydrate. During the leaching process, iron in the liquor was alternately oxidized by the pyrolusite and reduced by the pyrite. In an alternative leaching procedure, the heating of an aqueous slurry of pyrite in an autoclave first under oxygen pressure and then in the absence of oxygen produced an acidic ferrous sulphate solution suitable for the subsequent leaching of pyrolusite ore at ambient temperatur

ISSN:0008-4034    

DOI:10.1002/cjce.5450360104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1958

数据来源: WILEY