废SCR脱硝催化剂碱性浸出液制备白钨精矿工艺研究  

Preparation of Scheelite Concentrate from Alkaline Leaching Solution of Spent SCR Denitrification Catalyst

作　　者：刘晋隆 王晨晔[1,2,3] 王兴瑞 李会泉[1,2,3] LIU Jinlong;WANG Chenye;WANG Xingrui;LI Huiquan(Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;National Engineering Research Center for Green Recycling for Strategic Metal Resources,Beijing 100190,China;School of Chemical Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院过程工程研究所,北京100190 [2]战略金属资源绿色循环利用国家工程研究中心,北京100190 [3]中国科学院大学,北京100049

出　　处：《绿色矿冶》2024年第1期7-13,共7页Sustainable Mining and Metallurgy

基　　金：国家重点研发计划(No.2022YFC3901001);国家自然科学基金(No.52274411)。

摘　　要：目前,通常采用氢氧化钠碱浸法从废SCR脱硝催化剂中提取钨,得到含钨碱性浸出液。该浸出液中除钨之外还含有钒、硅、硫等杂质元素,并且由于溶液碱浓度较高,传统的萃取和吸附方法难以实施,传统盐酸中和-氯化钙沉淀法则会引入Cl-导致设备腐蚀。本文提出了一种新的硫酸镁脱硅-氧化钙沉淀工艺,进行除硅沉钨,制备白钨精矿。在硫酸镁脱硅过程中,通过使用硫酸来调节体系pH值为11,在镁硅摩尔比为0.9的条件下,可达到97.6%的硅脱除率。利用氧化钙将脱硅液沉淀生产白钨精矿,在钙钨摩尔比为1.1、温度108℃沸腾的最佳工艺条件下,得到的白钨精矿产品中WO3含量达到74.69%,硫含量为0.90%,硅含量为1.00%,满足YS/T 231—2015白钨精矿一级品标准。该工艺实现了废SCR脱硝催化剂碱性浸出液中钨的高效回收,同时避免了传统盐酸中和-氯化钙沉淀制备白钨精矿过程中引入Cl-可能导致设备腐蚀的问题。At present,sodium hydroxide alkali leaching method is usually used to extract tungsten from spent SCR denitration catalyst,and tungsten-containing alkaline leaching solution is obtained.In addition to tungsten,the alkaline leaching solution also contains impurity elements such as vanadium,silicon,and sulfur.Due to the high alkali concentration of the solution,traditional extraction and adsorption methods are difficult to implement.The traditional hydrochloric acid neutralization-calcium chloride precipitation method would take Cl-into the system,resulting in equipment corrosion.In this paper,a new magnesium sulfate desilication-calcium oxide precipitation process was proposed to remove silicon and precipitate tungsten to prepare scheelite concentrate.In the process of magnesium sulfate desilication,by using sulfuric acid to adjust the pH value of the system to 11,under the condition of magnesium-to-silicon molar ratio of 0.9,the silicon removal rate can reach 97.6%.The desilication solution was precipitated by calcium oxide to produce scheelite concentrate.Under the optimum process conditions of calcium-to-tungsten molar ratio of 1.1 and boiling temperature of 108℃,the WO 3 content in the obtained scheelite concentrate product reached 74.69%,the sulfur content was 0.90%,and the silicon content was 1.00%,which met the requirements of YS/T 231—2015 GradeⅠscheelite concentrate.The process realizes the efficient recovery of tungsten from the alkaline leaching solution of spent SCR denitration catalyst,and avoids the potential equipment corrosion issues associated with the traditional hydrochloric acid neutralization-calcium chloride precipitation method.

关 键 词：废SCR脱硝催化剂 钨资源回收 脱硅 沉淀 白钨精矿 

分 类 号：X701[环境科学与工程—环境工程] TF841.1[冶金工程—有色金属冶金]