5 results about "Sodium arsenate" patented technology

This invention discloses a method for the simultaneous removal of arsenic and chlorine from waste acid based on sodium arsenite minerals, belonging to the field of wastewater treatment and resource recovery technology. The method includes: adding an oxidant to the waste acid solution; supplementing copper, sodium, calcium, and chlorine sources according to the stoichiometric ratio of sodium arsenite (NaCaCu₅(AsO₄)₄Cl·5H₂O); conducting a water bath heating reaction under stirring conditions; adjusting the pH of the solution; and inducing Na₂O. + Ca 2+ In situ, sodium arsenate precipitate (sodium arsenate chlorite) is formed by the coordination precipitation reaction of Cu²⁺, As(V), and Cl⁻. After solid-liquid separation, washing, and drying, the sodium arsenate chlorite mineral is obtained. This invention utilizes the coexistence of arsenic and chlorine in pollutants. By adjusting the ratio of key components and controlling the reaction conditions, both arsenic and chlorine are simultaneously introduced into the mineral lattice, achieving efficient removal and resource conversion of arsenic and chlorine. This invention achieves synergistic removal and resource utilization of pollutants, resulting in significant environmental and economic benefits.

The invention discloses a method for removing arsenic and recovering copper from black copper sludge, and belongs to the technical field of secondary resource recovery of nonferrous metals. The method comprises the steps that firstly, oxidation leaching is conducted through oxygen in a sodium hydroxide alkaline medium, arsenic enters a solution in the form of sodium arsenate, valuable metal such as copper is enriched in slag, and efficient separation of arsenic and copper is achieved; copper-containing leaching residues can be returned to a copper smelting system to recover copper; adding calcium hydroxide into the sodium arsenate leachate for precipitation conversion to generate calcium arsenate slag to remove arsenic, and returning the regenerated sodium hydroxide solution to the leaching process for cyclic utilization; the technology is simple, the arsenic removal rate is high, the valuable metal recovery effect is good, regeneration and circulation of the reagent are achieved, and environment friendliness is achieved.

The application provides a method for comprehensively recovering calcium and arsenic from calcium-arsenic slag, comprising the following steps: S1: mixing and reacting calcium-arsenic slag and a sodium carbonate solution, and then filtering to obtain filtrate and filter residue containing calcium carbonate; washing the filter residue and collecting washing liquid A; the pH value of the mixing and reaction is 10-11; the temperature of the mixing and reaction is 25-60 DEG C; S2: mixing the filtrate and the washing liquid to obtain a sodium arsenate solution, adding ferrous sulfate, and controlling the oxidation-reduction potential to 400-550 mv by using hydrogen peroxide to precipitate arsenic. The application provides a method for comprehensively recovering calcium and arsenic from calcium-arsenic slag, the sodium-calcium replacement efficiency is improved by jointly controlling pH, temperature and liquid-solid ratio, the purity of the sodium arsenate solution is improved, then the pH-potential-iron-arsenic molar ratio is jointly controlled, under the conditions of relatively high pH, high potential and high iron-arsenic molar ratio, the tobermorite with a wheat grain shape is generated, and the leaching stability is good.

The invention discloses a method for synthesizing benzyl arsonic acid by acidizing arsenic acid. The method comprises the following steps: preparing arsenic acid, preparing sodium arsenite, adding benzyl chloride into the sodium arsenite to react to generate benzyl arsonic acid sodium, and standing for layering; acidizing arsenic acid until the pH value is 1-3 to generate benzyl arsonic acid and sodium arsenate; and adding a transforming agent into the sodium arsenate, and reacting for 2 hours to obtain a sodium arsenite solution which is recycled as a raw material. According to the method, the arsenic acid is used for replacing sulfuric acid to acidify the sodium benzyl arsonic acid to generate the benzyl arsonic acid, sulfate radicals are not introduced, and no sodium sulfate waste salt is generated; sodium arsenate is converted into sodium arsenite to be recycled as a raw material, so that cyclic utilization of sodium and arsenic is realized, and the method has remarkable environmental protection and resource utilization values.

The invention relates to a process for converting a feed containing sodium thioarsenate comprising the steps: step a) providing an aqueous solution comprising sodium thi- oarsenate, wherein the solution has an pH value above 10, step b) adding lime to the solution of step a) to form in an aqueous slurry, step c) pressure oxidizing the slurry of step b) with oxygen, wherein oxygen is provided with an oxygen pressure of at least 6 bar, wherein the slurry is heated to a temperature of at least 100°C, and wherein a pH value above 10 is maintained during the pressure oxidation, to generate johnbaumite.