Suggested is a method for recovering precious metals from secondary resources comprising or consisting of the following steps: (a) providing a source of solid waste material comprising precious metals in an amount of at least 0.0001% b.w.; (b) bringing said waste material into contact with heterotrophic micro-organisms capable of producing and releasing hydrocyanic acid; (c) adding a solvent or an aqueous nutrient solution capable of serving as a nutrient source for said micro-organisms to the mixture; (d) depleting said waste materials from the precious metals contained therein by complexation of the metals with said hydrocyanic acid released by said micro-organisms; (e) separating the depleted solid waste material from the liquid containing the metal-cyano complexes; (f) recovering the precious metals from their cyano-complexes in known manner.

The invention discloses a method for co-processing cracking slag and smelting soot of the waste circuit board, belongs to the field of comprehensive recycling of valuable elements from typical soot of waste circuit boards, and particularly relates to a method for co-processing cracking slag and smelting soot of the waste circuit board for debromination and comprehensive recovery of copper and zinc. The method mainly comprises the following steps of: crushing and sorting, mixture roasting, reinforced leaching, replacement and silver precipitation, sulfuration and copper precipitation, and evaporation crystallization. Compared with a traditional recycling technology, the purpose that two kinds of solid waste are treated in a coupling mode through one recycling technology is achieved. Through mixed sulfuric acid roasting, the requirement of bromide synergistic removal of the waste circuit board cracking slag and smelting soot is met, and the purpose of selective conversion of copper and zinc is achieved.

A method for extracting noble metals from mining tailings and other solids is provided. The method uses a Lewis acid, Brønsted acid, complexing agent and oxygen to provide excellent extraction without the need for chorine gas or cyanide.

The invention relates to a method of recovering Pt or Ag or Pt and Ag from a sulfate solution on an electrode. In particular, the invention concerns a method for recovering Pt or Ag or Pt and Ag from base metal bearing process solution, particularly from a hydrometallurgical sacrificial metal bearing solution containing Zn and/or Ni. In general, the method of the present invention can be used for recovery of precious metals, which are dissolvable in sulfuric acid, from sulfate media based solutions. In addition to Pt and Ag, especially Pd should be mentioned. Deposited precious metal(s) can be recovered from the electrode or the deposition containing electrode can be used as such.

Any metal having a low α-ray emission, the metal being any one of tin, silver, copper, zinc, or indium, wherein an emission of an α-ray after heating the metal at 100° C. in an atmosphere for six hours is 0.002 cph/cm.sup.2 or less. Any metal of tin, silver, copper, zinc and indium each including lead as an impurity is dissolved to prepare a hydrosulfate aqueous solution of the metal and lead sulfate is precipitated and removed in the solution. The lead sulfate is precipitated in the hydrosulfate aqueous solution by adding a lead nitrate aqueous solution including lead having an α-ray emission of 10 cph/cm.sup.2 or less to the hydrosulfate aqueous solution, from which the lead sulfate has been removed, and, at the same time, the solution is circulated while removing the lead sulfate to electrowinning the metal using the hydrosulfate aqueous solution as an electrolytic solution.

The invention relates to a method for recovering precious metals from electronic waste utilising biometallurgical techniques. In one aspect, a method of recovering one or more target metals from electronic waste, includes (a) removing at least a portion of non-target material from the electronic waste or grinding to a preselected size particle to give pre-processed electronic waste; (b) contacting the pre-processed electronic waste with a lixiviant such that at least a portion of the target metal(s) dissolve into the lixiviant to produce a pregnant solution; (c) contacting a microorganism with the pregnant solution such that at least a portion of the target metal(s) ions biosorb to the microorganism wherein the microorganism becomes metal laden and the pregnant solution becomes barren; (d) substantially separating the metal laden microorganism from the barren solution; and (e) recovery of the target metal(s) from the metal laden microorganism.

A method for producing a collector alloy comprising 25 to 100 wt % precious metal in total, comprising 0 to <97 wt % of the precious metal silver, 0 to 75 wt % of at least one precious metal selected from gold, platinum, rhodium and palladium, and 0 to 75 wt % of at least one non-precious metal selected from copper, iron, tin and nickel, or for producing pure silver, comprising the steps of: (1) providing precious metal sweeps; (2) providing a flux which, during collective melting with the refractory inorganic material from the precious metal sweeps provided in step (1); (3) collective melting of the materials provided in steps (1) and (2) at a temperature in the range of from 1300 to 1600° C., forming a melt comprising at least two phases of different densities arranged one above the other; and. (4) separating the upper phase and the lower phase.

A method for producing a collector alloy comprising 25 to 100 wt % precious metal in total, comprising 0 to <97 wt % of the precious metal silver, 0 to 75 wt % of at least one precious metal selected from gold, platinum, rhodium and palladium, and 0 to 75 wt % of at least one non-precious metal selected from copper, iron, tin and nickel, or for producing pure silver, comprising the steps of: (1) providing precious metal sweeps; (2) providing a flux which, during collective melting with the refractory inorganic material from the precious metal sweeps provided in step (1); (3) collective melting of the materials provided in steps (1) and (2) at a temperature in the range of from 1300 to 1600° C., forming a melt comprising at least two phases of different densities arranged one above the other; and. (4) separating the upper phase and the lower phase.

A process for separating a fusion mix sample comprising a slag material and a collector material using a separator. The separator comprising a plurality of impact members configured to rotate. The process comprising the steps of providing a solid fusion mix sample and loading the solid sample into the separator. Dislodging the slag material from the solid fusion mix sample by rotating the impact members and contacting the rotating impact members and the solid fusion mix sample. Separating into a first fraction substantially comprising the collector material and a second fraction substantially comprising slag material.

A process for separating a fusion mix sample comprising a slag material and a collector material using a separator. The separator comprising a plurality of impact members configured to rotate. The process comprising the steps of providing a solid fusion mix sample and loading the solid sample into the separator. Dislodging the slag material from the solid fusion mix sample by rotating the impact members and contacting the rotating impact members and the solid fusion mix sample. Separating into a first fraction substantially comprising the collector material and a second fraction substantially comprising slag material.