醋酸乙烯合成用废催化剂提锌新工艺研究

Research on New Process for Extracting Zinc from Spent Catalyst Used in Vinyl Acetate Synthesize

针对醋酸乙烯合成用废催化剂利用中存在的问题,提出了废催化剂经微波辐射预处理后用氨水和碳酸氢铵的水溶液浸出锌的新工艺,研究了微波预处理和浸出工艺条件对锌浸出率的影响。试验结果表明:微波预处理可使锌的浸出率大大提高;将废催化剂通过微波辐射预处理到950℃,每千克废催化剂加入387.5 g碳酸氢铵和900 mL氨水作为浸出剂,按液固比2∶1搅拌浸出3 h,洗涤4次,锌的浸出率平均达到93.45%。新工艺锌浸出率高,流程短,可在常温常压下浸出,无废液,具有较广阔的应用前景。

In view of the problems existing in the utilization of the spent catalyst from vinyl acetate synthesize, a new process was proposed for extracting the zinc from the micro-wave pretreated spent catalyst by the aqueous solution of ammonia and ammonium hydrogen carbonate. The effect of the micro-wave pretreatment and leaching process conditions on the zinc leaching rate was investigated. The results show that micro-wave pretreatment can greatly improve the zinc leaching rate. It reached 93.45% averagely at a micro-wave pretreatment of the spent catalyst to 950 ℃ , addition of 387.5 g ammonium hydrogen carbonate and 900 mL ammonia per kg spent catalyst, 3 h agitation at a liquid-solid ratio of 2：1 and rinsing for four times. The new process has advantages of high zinc leaching rate, short flowsheet, leaching at normal temperature and pressure and no waste solution, suggesting a wide application field and good prospect.