磷酸三丁酯萃取脱硫废液中硫氰酸根的初步研究.pdf

第22卷第2期
化学研究与应用
Vol 22. No. 2
2010年2月
Chemical Research and Application
Feb.,2010
文章编号:1004-1656(2010)02-0213-05
磷酸三丁酯萃取脱硫废液中硫氰酸根的初步研究
陈林,周小华
(重庆大学化学化工学院,重庆40004)
关键词:磷酸三丁酯;萃取;硫氰酸根;硫代硫酸根
中图分类号:T0028.32文献标识码:A
Preliminary study on TBP extraction of thiocyanate from
waste solution for coke oven gas desulfurization
CHEN Lin ZHOU Xiao-hua
College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China)
Abstract: The ex ract on of ic ana e( M from potassium thiocyanate( KSCN solution and waste solution for coke oven gas
desulfurization using tributyl phosphate ( TBP and affect of several factors were investigated. IR analysis shows that TBP is able to
extact N ut can not e tract thiosul ate anion($ 0 For extaction from 6% KSCN solution with TBP, the single extraction
rate of N is 10.95 an the partition c cient is O 1230. S N is ex racted by TBP via the formation of corination bond. The
main impacting factors on extraction includes phase ratio, extraction time, and the presence of NH.For extracting SCN from
diluted waste solution for coke oven gas desulfurization, the average single extraction rate is 15. 39%, and the waste solution can be
reused after desalting extraction. The single stripping rate is 61. 73% using distilled water as strippant. The total stripping rate can
reach 95. 15%, after stripping for three times. For reuse of TBP that removed SN,it must be undergone further purification
Key words: tbutyl phosphate; extraction thiocyanate; thiosulfate anion
焦炉煤气含污染物H2S5g/m3~8g/m3、HCN杂质,致使获得的硫氰酸铵纯度低。因此有必要
lg/m2~2.5g/mt),目前主要用催化氧化-氨水吸研发低成本、高效率、绿色环保的分离脱硫脱氰废
收法(NH3-OMC)工艺处理。由此产生的脱硫脱氰液中SCN或S2032的方法,以实现废液回用。硫
废液中主要含有 NH SCN、(NH4)2S2Oっ等无机盐,氰酸盐及硫代硫酸盐在医药、纺织、染料、农药等
其中,SCN及S2,032浓度均影响脱硫催化剂的效行业有广泛应用。液液萃取有选择性高、分离
率,规定其总浓度不得超过250g/L。因此须不断效果好溶剂可反复使用、能耗低、污染小、易规模
去除SCN或S2032,方可实现废液的循环利用。化生产等优点,广泛应用于分析化学、原子能、治
目前,处理该类废液的主要方式有:高温裂解法金、电子、环境保护、生物化学和医药等领域?,因
和分步结晶法]。前者先将脱硫脱氯废液加热到此从脱硫废液中萃取分离SCN或S20,2,不仅能
140℃以上,使 NHL SCN和(NH,)2S203分解,再将变废为宝,还保护环境
其升温至300℃完全分解成NH3、H2S、CO2及N2,
中性萃取剂磷酸三丁酯(TBP),活性基团为
能耗极高,实际上是将水体污染物转移至空气,造礫氧基团的氧原子,其价电子层的空轨道可接受
成二次污染;分步结晶法先将脱硫脱氰废液浓缩、溶质孤对电子形成配位键,实现萃取。分析SCN、
脱色后再结晶,能耗高,由于未有效除去废液中的S203结构可知,SCN的N有孤对电子,可与有空
收稿日期:2009-06-29;修回日期:200909-28
联系人简介:周小华(1955-),男,教授,主要研究方向:生物化工和药物化学。Email.zhou6306590@tom.com