Abstract: A method for recovering valuable metals, which include at least one M element selected from the group consisting of Mo, Ni and Co, and V, in the form of iron-based alloys from a waste containing the valuable metals, comprising the steps of (a) roasting the waste to form a roasted ore containing oxides of the valuable metals; (b-1) heating the roasted ore together with an iron source and a flux, to form an iron-based alloy melt; (b-2) adding a reducing agent having higher affinity for oxygen than V at a reduction temperature to the melt, thereby reducing the oxides of the valuable metals to form an Fe-M-V alloy melt; (c) oxidizing substantially only V in the Fe-M-V alloy melt to form a V-oxide-containing slag and an Fe-M alloy melt; and (d) separating the V-oxide-containing slag from the Fe-M alloy melt.

Abstract: In the electro-dissolution process for hard alloy recovery, the longitudinal acid flow is replaced by a transversal flow to progress the running quality of electrolyte; a supersonic wave device is set for increasing the reaction speed and preventing the oxidation bed from forming; a supersonic wave cleaner is used for cleaning the impurity ions; grinding process is improved for maintaining the original shape of hard particles (WC, VC, TiC, etc); magnetic separators are used for separating the residual metal binder (Co, Ni, Cr, etc) out of the powders.

Abstract: The method of producing a carrier of the invention includes a step of kneading the starting carrier components, solid binding agent, liquid binding agent and diluted nitric acid water. The starting carrier components comprise aluminum hydroxide, pseudoboehmite, ?-alumina, powdery silica gel, powdery natural silica and zeolite. The solid binding agent comprises a powder of ?-starch (rice), ?-starch (potato), ?-starch (tapioca), funori (glue plant), crystalline cellulose and powdery cellulose. The liquid binding agent comprises colloidal alumina, colloidal silica and polyvinyl alcohol. As a de-firing agent, further, there are used wood powder, charcoal powder, rice flour, wheat flour, barley flour, buck wheat flour and corn. The carrier has a pore volume in a range of 0.52 to 0.84 cc/g and a side crushing strength in a range of 2.2 to 11.0 kgf/particle.