42 results about "Calcium arsenite" patented technology

The invention relates to a method for precipitating pentavalent calcium arsenate from an acidic solution, in which arsenic is at least partially in trivalent form. The acidic solution is neutralised before being routed to an arsenic oxidation stage,and a poorly soluble calcium-arsenic compound is precipitated from the solution, in which all the arsenic is pentavalent.

The invention relates to a comprehensive recovery method for complicated materials containing arsenic and valuable metal slag dust, which comprises the following steps of: treating various arsenic-containing materials into a primary rotary kiln to volatilize the arsenic, and treating the materials into a secondary rotary kiln for purifying the arsenic to produce arsenic products containing 99.5 percent of As2O3; carrying out reduction melting on primary and secondary rotary kiln slag through a blast volatilization furnace, returning produced high-arsenic smoke dust back into the primary rotary kiln for treatment, using furnace slag as cement plant raw materials and zinc raw materials for carrying out resource treatment after the forced reduction arsenic removal and zinc volatilization through a fuming furnace, carrying out alkaline oxidation refining treatment on produced arsenic containing alloy, recovering lead, antimony, bismuth, silver and the like in the arsenic removal alloy according to the conventional method, carrying out crushing alkali dissolution and filtering on refined alkali slag with 5 to 15 percent of As2O3 and about 5 to 15 percent of valuable metal content, returning slag back into the blast volatilization furnace to be treated, introducing CO2 into tin and arsenic containing solution for precipitating the arsenic, using filtered stannic oxide as high-tin raw materials to be sold, carrying out arsenic precipitating and filtering through adding Ca(OH)2 into arsenic containing filter liquor, returning calcium arsenate slag back into the primary rotary kilnfor treatment after the filtration, and evaporating and concentrating the rest alkali liquid for recovering the alkali. The whole technical process of the method provided by the invention is simple and smooth, economic benefits and environment benefits are very obvious.

The invention discloses a method for separating arsenic and selenium from copper anode slime alkaline leach liquor. The method comprises the following steps: 1) oxidation, namely adding an oxidizing agent or introducing oxidizing gas into the copper anode slime alkaline leach liquor, so that oxidized copper anode slime alkaline leach liquor is obtained; 2) arsenic precipitation, namely adding a calcium salt into the oxidized copper anode slime alkaline leach liquor, stirring the obtained mixture so as to produce a precipitate, and carrying out filtration and separation on the precipitate so as to obtain a calcium arsenate precipitate and arsenic post-precipitation liquid; and 3) selenium precipitation, namely adding a barium salt into the arsenic post-precipitation liquid obtained in the step 2), stirring the obtained mixture so as to produce a precipitate, carrying out filtration and separation on the precipitate so as to obtain a barium selenate precipitate and selenium post-precipitation liquid, and carrying out evaporative crystallization on the selenium post-precipitation liquid so as to recycle alkali, or directly returning to a leaching process. The method disclosed by the invention is short in technological process, less in equipment and simple in operation, and can be used for realizing the separation and enrichment of arsenic and selenium, the precipitation rate of arsenic is higher than 96%, and the precipitation rate of selenium is higher than 99%; by virtue of carrying out evaporative crystallization on a solution for recycling or directly returning the solution to a leaching process, the recovery of alkali is realized.

The invention relates to a method for preparing high-stability solid arsenic minerals through a distributed crystallization method. The method comprises the following steps: removing arsenic from a high-arsenic-content solution and curing the solution, so as to carry out harmless treatment on the arsenic-containing solution. According to the method disclosed by the invention, trivalent arsenic in the arsenic-containing solution is catalytically oxidized into pentavalent arsenic; and the oxidized solution is synthesized into the high-stability solid arsenic minerals through a lime arsenic settling method and the distributed crystallization method, and the high-stability solid arsenic minerals can be directly stockpiled. Calcium arsenate is obtained firstly through the lime arsenic settling method, and then the calcium arsenate is turned into the high-stability solid arsenic minerals through the distributed crystallization method; and toxicity extraction meets the specifications of GB5085.3-2007 (solid waste authentication standard-extraction toxicity authentication). The method is short in technological flow and good in arsenic settling effect; the solution subjected to arsenic settling can be directly discharged, and the synthesized solid arsenic minerals are high in stability and can be stably stockpiled within a wide pH range of 2 to 11 and under a strong reducing property condition.

The invention discloses a stabilized treatment method for realgar tailing residues. The stabilized treatment method for the realgar tailing residues comprises the following steps of (1) crushing the realgar tailing residues, adding water inside, uniformly stirring, and carrying out first-stage microwave treatment under the action of a microwave field at the power ranging from 100W to 300W; (2) adding water and ferrous salt inside, uniformly stirring, feeding air or oxygen, and meanwhile, carrying out second-stage microwave treatment under the action of a microwave field at the power ranging from 300W to 500W; and (3) carrying out third-stage microwave treatment under the action of a microwave field at the power ranging from 500W to 700W, so that the stabilization of the realgar tailing residues is realized. According to the stabilized treatment method for the realgar tailing residues provided by the invention, through designing a whole process technology of the method, especially improving parameters and conditions of a key microwave treatment process, and dissolving, oxidizing and stabilizing the realgar tailing residues for three stages, the problems of slow calcium arsenate dissolution rate, slow arsenic sulfide oxidation rate and insufficient product long-time stability can be effectively solved.

The invention discloses a separation method for antimony and arsenic in an antimony and arsenic material. The separation method comprises the following steps of uniformly mixing the antimony and arsenic material with sodium peroxide, calcining the mixture at 300-390 DEG C, adding water into the calcined product, stirring the calcined product, leaching the calcined product at 50-65 DEG C, filteringthe calcined product after leaching to obtain a lixivium; and adding calcium oxide into the lixivium, stirring the lixivium at a constant temperature, filtering the lixivium after full reaction to obtain filter residues and filtrate, and drying the filter residues to obtain a calcium arsenate product. By taking sodium peroxide as a primary raw material, the calcining temperature is relatively low, antimony and arsenic are prevented from being volatilized in the calcining process, and the antimony and arsenic recovery rates in later period are relatively high. Sodium peroxide which replaces sodium nitrate is taken as an oxidant, so that the material is oxidized more fully without generating oxynitride, and the environment is not polluted. As alkali is not added, the raw materials are low in cost and equipment is not corroded.