Recovery of Molybdenum and Vanadium from spent Hydro-processing Catalyst

Molybdenum and vanadium have strategic and industrial importance due to their applications in many technological fields (1-2). However, with the ceaseless exploitation of resources in the world, the high grade ore is exhausted day by day, primary sources are presently insufficient to fulfill the demand and thus secondary sources are being increasingly exploited. Since the processing cost of low-grade ore is becoming higher and higher and the implementa-tion of rigorous environmental rules, many countries in the world pay much attention to the comprehensive utiliza-tion of the secondary resources. There are various by products and waste materials which are being exploited as a secondary sources for Mo, V, Ni etc recovery such as by-products of U and Cu recovery(2a), fly ash(2b), spent catalyst et