A hydrometallurgical process for the removal of arsenic and antimony from a so-called dirty copper concentrate (101) is described. The process comprises the following steps: Step 1: repulping (100) the dirty copper concentrate with an alkaline lixiviant (102, 103), and subjecting the dirty copper concentrate to an alkaline leaching process (the Leach) in a Leach reactor (110). The arsenic and antimony are dissolved in the Leach to produce a clean copper concentrate (138) and leach discharge liquor (132). Step 2: subjecting the Leach discharge liquor (132) to a lime treatment step (151) in order to regenerate (150) the alkaline lixiviant as well as precipitate an impurity rich precipitate (161) containing arsenic and antimony. Then the impurity rich precipitate (161) is separated (160) from the regenerated alkaline lixiviant (162). The impurity rich precipitate is washed and disposed of in an environmentally safe condition. Step 3: recycling the regenerated alkaline lixiviant (162) to the Leach in Step 1, and so employing the recycled alkaline lixiviant (102) in the further extraction of arsenic and antimony from incoming dirty copper concentrate (101).

A hydrometallurgical process for the removal of arsenic and antimony from a so-called dirty copper concentrate (101) is described. The process comprises the following steps: Step 1: repulping (100) the dirty copper concentrate with an alkaline lixiviant (102, 103), and subjecting the dirty copper concentrate to an alkaline leaching process (the Leach) in a Leach reactor (110). The arsenic and antimony are dissolved in the Leach to produce a clean copper concentrate (138) and leach discharge liquor (132). Step 2: subjecting the Leach discharge liquor (132) to a lime treatment step (151) in order to regenerate (150) the alkaline lixiviant as well as precipitate an impurity rich precipitate (161) containing arsenic and antimony. Then the impurity rich precipitate (161) is separated (160) from the regenerated alkaline lixiviant (162). The impurity rich precipitate is washed and disposed of in an environmentally safe condition. Step 3: recycling the regenerated alkaline lixiviant (162) to the Leach in Step 1, and so employing the recycled alkaline lixiviant (102) in the further extraction of arsenic and antimony from incoming dirty copper concentrate (101).

A stabilization process for an arsenic solution comprising thiosulfates, the process comprising: acidifying the arsenic solution to decompose the thiosulfates, to yield an acidified solution; oxidizing the acidified solution to oxidize residual As.sup.3+ to As.sup.5+ and reduced sulfur species to sulfates, to yield a slurry comprising elemental sulfur; separating elemental sulfur from the slurry to yield a liquid; oxidizing the liquid to oxidize residual reduced sulfur species, to yield an oxidized solution; and forming a stable arsenic compound from the oxidized solution.

A stabilization process for an arsenic solution comprising thiosulfates, the process comprising: acidifying the arsenic solution to decompose the thiosulfates, to yield an acidified solution; oxidizing the acidified solution to oxidize residual As.sup.3+ to As.sup.5+ and reduced sulfur species to sulfates, to yield a slurry comprising elemental sulfur; separating elemental sulfur from the slurry to yield a liquid; oxidizing the liquid to oxidize residual reduced sulfur species, to yield an oxidized solution; and forming a stable arsenic compound from the oxidized solution.

A purification apparatus and purification method of a non-metallic semiconductor material relate to the field of preparation of high-purity materials, and are especially applicable to preparation of high-purity non-metal materials, in particular to an apparatus and method for purifying a non-metallic semiconductor material by means of a metal melt. The apparatus includes a furnace body, a pressure balance valve, a crucible disposed in the middle of the lower part of the furnace body, a heating and supporting structure for the crucible, a liftable injection mechanism disposed right above the crucible, and a liftable and rotatable recovery mechanism disposed next to the liftable injection mechanism. The method is completed based on the purification apparatus, and includes: injecting the gasified non-metal material into the metal melt under a high pressure environment; reducing the ambient pressure, and collecting the bubbles volatilized from the metal melt to obtain the purified non-metal material. The technical solution proposed in the present invention can be used to effectively remove impurities in the non-metal material, especially remove elements of similar properties. The apparatus is highly integrated and easy to control, and the method is simple.

A method for treating a mineral composition containing iron, arsenic or other Group VA compounds comprises milling the mineral composition to a particle size of P.sub.80 of less than 25 m and leaching the mineral composition in the presence of lime and/or limestone and a soluble alkali complexing agent and in the presence of an oxygen containing gas at a pH in the range of from 3.5 to 6.

A method for treating a mineral composition containing iron, arsenic or other Group VA compounds comprises milling the mineral composition to a particle size of P.sub.80 of less than 25 m and leaching the mineral composition in the presence of lime and/or limestone and a soluble alkali complexing agent and in the presence of an oxygen containing gas at a pH in the range of from 3.5 to 6.

Provided is a recovery method for valuable metals in copper anode slime. By using the recovery method of the disclosure, selenium, copper, tellurium, arsenic, lead, bismuth, and precious metals gold and silver in the copper anode slime are recovered. The method adopts two-step vacuum carbothermal reduction to replace reduction smelting of anode slime and stepwise blowing of noble lead in the traditional pyrometallurgy, and avoids the emission of arsenic-containing soot in the traditional process. The recovered gold-rich residue contains almost no base metals such as lead, bismuth, antimony, and arsenic. After subjecting the gold-rich residue to leaching gold by chlorination and reduction, a gold powder could be obtained therefrom with a lower content of base metals than traditional processes. Therefore, the method greatly reduces the amount of produced slag, shortens the production cycle, and reduces the loss of precious metals in the slag.

Provided is a recovery method for valuable metals in copper anode slime. By using the recovery method of the disclosure, selenium, copper, tellurium, arsenic, lead, bismuth, and precious metals gold and silver in the copper anode slime are recovered. The method adopts two-step vacuum carbothermal reduction to replace reduction smelting of anode slime and stepwise blowing of noble lead in the traditional pyrometallurgy, and avoids the emission of arsenic-containing soot in the traditional process. The recovered gold-rich residue contains almost no base metals such as lead, bismuth, antimony, and arsenic. After subjecting the gold-rich residue to leaching gold by chlorination and reduction, a gold powder could be obtained therefrom with a lower content of base metals than traditional processes. Therefore, the method greatly reduces the amount of produced slag, shortens the production cycle, and reduces the loss of precious metals in the slag.

A method for immobilizing arsenic includes adding calcium arsenate to a glass-forming material containing iron, silica, and alkaline components so that an iron/silica weight ratio is in a range of 0.5 to 0.9 and an amount of alkaline components is in a range of 14 wt % to 26 wt %, and thereby incorporating the arsenic into a glass solidified body. For example, the method for immobilizing arsenic may include: adding an alkaline solution and an oxidizing agent to a copper-arsenic-containing substance, and thereby carrying out an oxidizing leaching; separating a leach residue by solid-liquid separation; adding calcium hydroxide to a recovered alkaline arsenate solution to generate calcium arsenate; and adding the glass-forming material to the recovered calcium arsenate so that the iron/silica weight ratio and the amount of alkaline components are in the above-mentioned ranges, and thereby incorporating the arsenic into the glass solidified body.