废加氢催化剂的回收现状与研究进展

Status and research progress on recovery of spent hydrogenation catalysts

废加氢催化剂因含难降解有机物和Mo、W、Ni、Co、V等战略金属,是危险废弃物和重要的二次资源,资源化利用具有显著的经济、社会和环境效益。本文介绍了加氢催化剂概况,综述了废加氢催化剂的回收现状,包括酸浸出、碱浸出、焙烧-浸出、火法富集。文章指出,回收前需采用溶剂洗涤法、机械法或焙烧法进行有机物脱除。酸法浸出酸浓度较高,对设备腐蚀性大;碱法浸出对Ni和Co的回收率低,采用碱法、酸法两步浸出可实现多金属高效回收;但湿法回收存在废水量大、污染严重等问题。焙烧-浸出是目前主流回收方法,已产业化应用,但存在回收流程长、后续浸出废水量大等问题。针对现有技术废水量大、污染严重等问题,本文提出了碳热还原富集回收有价金属、尾渣用于绿色建材的方法。

Spent hydrogenation catalysts are hazardous wastes and important secondary resources because they contain refractory organics and strategic metals such as Mo,W,Ni,Co and V.Resource utilization of spent catalysts has significant economic,social and environmental benefits.In this paper,the general situation of hydrogenation catalysts is introduced,and the recovery status of spent hydrogenation catalysts,including acid leaching,alkali leaching,roasting-leaching progress and pyrometallurgical progress is reviewed.Organic matter should be removed by solvent washing,mechanical method or roasting before recovery.The acid concentration of acid leaching is high,which is corrosive to equipment.The recovery rate of Ni and Co by alkali leaching is low,and the high-efficiency recovery of polymetallic can be realized by alkali leaching and acid leaching.However,hydrometallurgical progress has serious problems,such as the generation of wastewater and serious pollution.Roasting-leaching is the main recovery method at present,which has been industrially applied,but there are some problems such as long recovery process and a large amount of subsequent leaching wastewater.In order to solve the problems of water pollution,the method of enriching and recovering valuable metals by carbothermic reduction and using tailings for green building materials is put forward,and the prospect of metal recovery of waste catalyst is discussed.