摘要
研究了铬酸钠在氨和二氧化碳介质中脱钠转化反应时氨盐比、铬酸钠溶液初始浓度、温度等对反应转化率的影响，测定了25℃和35℃下Na+，NH4+CrO42-－H2O体系的溶解度和相图，并以此分析了反应过程中CrO42-的析出形式及铬酸铵的分离方法，发现在反应过程中生成铬酸铵钠复盐，以N42CrO4为盐析剂能够使反应后溶液中绝大部分CrO42-以NaNH4CrO4·2H2O复盐结晶形式析出，铵盐中间体具有易分解的特性，为开发铬盐转化的新途径提供了依据．
The reaction process of sodium chromate with carbon dioxide and ammoniawas studied. The effect of ammonia to sodium chromate molar ratio, concentration of sodiumchromate and temperature on conversion rate was investigated. The results show that ratioof ammonia to sodium chromate of 2, concentration of sodium chromate of 40%, temperatureat 30℃ are proper conditions. The solubility of the Na+, NHk4+ CrO42-－H2O system wasdetermined at 25℃ and 35℃. The crystals of double-salt NaNH4CrO4·2H2O, (NH4)2CrO4and NaHCO3 may coexist in the solid phase. (NH4)2CrO4 in the reacted solution can beseparated as NaNH4CrO4·2H2O crystal by salting-out with Na2CrO4.
出处
《化工冶金》
CSCD
北大核心
1999年第4期410-414,共5页
基金
中国科学院"九.五"重大及特别项目!KZ95T-05
关键词
碳氨转化
转化率
溶解度
相图
铬酸钠
二氧化碳
Ammonium bicarbonate conversion, Conversion rate, Solubility, Phase diagram
