对调吡脲(氯吡脲/CPPU)生产过程中产生的废液中的甲苯和2-氯-4-氨基吡啶进行了回收利用研究,考察和优化了处理条件,得到甲苯的最佳回收工艺路线:用0.1 mol/L硫酸处理液与废液按1∶30的质量比加热回流2h,经分液、干燥、过滤、蒸馏后得到回收甲苯,经气相色谱检测,纯度为99.4％.进一步对处理过甲苯的废液进行2-氯-4-氨基吡啶的回收研究,得到2-氯-4-氨基吡啶回收的最佳工艺条件为:废液pH为12～13,萃取时间为6min,进行萃取剂与废液体积比为2的5级错流萃取,回收率达到94％以上,经液相色谱检测,纯度达到97.5％,实现了废弃物资源化利用的目的.%Recovery of methylbenzene and 2-chloro-4-amino pyridine from waste in producing forchlorfenuro was studied in this paper. The operational path has been obtained after inspecting and optimizing the disposing condition, and they are described in the following. The mixture of sulfuric acid (0.1 mol/L) and waste liquid in mass ratio of 1:30 was refluxed for 2 h. Then toluene was obtained from the waste by liquid separation, drying, filtertion and distillation. By gas chromatography,the purity of recovered toluene was 99.4%. After toluene was recovered from the waste liquid, the recovery optimum conditions of the resulting liquid containing 2-chloro-4-amino pyridine were further studied in detail. The best optimum conditions were obtained: the waste liquor pH is between 12 and 13, the extraction time is 6 min, with a flow ratio of 2 and 5-stage cross-flow extractions, the experimental recoveries exceed 94%, the purity is 97.5% by liquid chromatography. The utilization of waste was finally achieved.
展开▼
