摘要
对模拟高放废液中Ｆｅ（Ⅲ）的还原与还原剂类型、用量、还原时间，支持还原剂类型及用量的关系进行了初步研究。抗坏血酸（Ｃ６Ｈ８Ｏ６）是较合适的还原剂，硝酸肼（Ｎ２Ｈ４·ＨＮＯ３）和氨基磺酸（ＮＨ２ＳＯ３Ｈ）可以作为支持还原剂。模拟高放废液酸度为１ｍｏｌ／Ｌ时，采用Ｇ６Ｈ８Ｏ６作还原剂，Ｎ２Ｈ４·ＨＮＯ３作支持还原剂，可使模拟料液中９０％以上的Ｆｅ（Ⅲ）还原成Ｆｅ（Ⅱ）。当用３０％ＴＲＰＯ—煤油溶液与上述溶液萃取平衡１小时后，８０％以上的铁仍处于Ｆｅ（Ⅲ）状态。由于３０％ＴＲＰＯ不萃取Ｆｅ（Ⅱ），采用还原Ｆｅ（Ⅲ）为Ｆｅ（Ⅱ）的方法，可用３０％ＴＲＰＯ—煤油直接萃取模拟高放废液（［ＨＮＯ３］＜１．４ｍｏｌ／Ｌ），萃取体系也不会产生第三相。
Fe(Ⅲ) reduction is studied in simulated high level liquid waste (HLW) with different chemi caf reductants. Ascorbic acid is an applicable reductant. Hydrazine nitrate and sulfamic acid could be served as protecting reduction agents. When the acidity of simulated HLW is 1mol/L HNO3, by addition of 0. 259 ascorbic acid as a reductant and 0. 2ml of 10 mol/L hydrazine nitrate as a protecting reduction agent into 10 ml simulated HLW solution, more than 90% Fe(Ⅲ) are reducted to Fe(Ⅱ). But by using 3o% TRPO extractant more than 80% Fe(Ⅲ) remained at Fe(Ⅱ) state after an hour extraction. The third phase would disappear when 30% TRPO extractant is processed with present Chinese HLW([HNO] < 1. 4mol/L)without dilution.
出处
《核科学与工程》
CSCD
北大核心
1996年第2期160-167,共8页
Nuclear Science and Engineering
