Hydrometallurgical route to recover molybdenum, nickel, cobalt and aluminum from spent hydrotreating catalysts in acid medium

Quimica nova

Afonso, Julio Carlos¹  Paulino, Jéssica Frontino¹  Valverde Júnior, Ivam Macedo¹ 

[1] Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil

关键词: spent catalysts;    metal recovery;    waste management.;   

DOI  :  10.1590/S0100-40422008000300036

学科分类：化学（综合）

来源: Sociedade Brasileira de Quimica

【 摘 要 】

This work describes a hydrometallurgical routefor processing spent commercial catalysts (CoMo and NiMo/Al2O3).Samples were preoxidized (500 ºC, 5 h) in order to eliminate coke and othervolatile species present. The calcined solid was dissolved in concentrated H2SO4and water (1:1 vol/vol) at 90 ºC; the insoluble matter was separated fromthe solution. Molybdenum was recovered by solvent extraction using tertiaryamines at pH around 1.8. Cobalt (or nickel) was separated by addition of aqueousammonium oxalate at the above pH. Phosphorus was removed by passing the liquidthrough a strong anion exchange column. Aluminum was recovered by neutralizingthe solution with NaOH. The route presented in this work generates less finalaqueous wastes because it is not necessary to use alkaline medium during themetal recovery steps.

【 授权许可】

CC BY