Method for preparing sodium pyroantimonate by using waste antimony pentachloride as raw material

Abstract

The invention discloses a method for preparing sodium pyroantimonate by using waste antimony pentachloride as a raw material. The method comprises the following steps of A, an extraction step, wherein a waste antimony pentachloride catalyst is extracted by using industrial water to obtain an organic phase and an inorganic phase, the inorganic phase is separated to obtain an antimony ion containing water solution, and the volume ratio of the waste catalyst to the industrial water is 1:0.5-1:2; B, an oxidation step, wherein the antimony ion containing water solution is oxidized by using hydrogen peroxide to obtain antimony oxidation liquid, and the hydrogen peroxide water using amount is 1-2 times of the theoretic using amount; and C, a neutralization step, wherein neutralization reaction on the antimony oxidation liquid is carried out by using sodium hydroxide water solution, a pH value of the reaction liquid is regulated to be between 7 and 13, and after the reaction is carried out for 10-300 minutes at 50-90 DEG C, cooling, filtering, washing and drying are performed to obtain sodium pyroantimonate. The method has the advantages of simple process, low material consumption, low cost, good quality of the product and environmental friendliness; the extraction ratio of antimony is more than 99.2 percent, and the highest is 99.85 percent; and the total yield of antimony is more than 98 percent, and the highest is 99.65 percent.

Description

technical field [0001] The invention relates to the technical field of waste catalyst recovery, in particular to a method for preparing sodium pyroantimonate by using waste antimony pentachloride catalyst as a raw material. Background technique [0002] In the production of fluorine chemical industry, the catalyst commonly used in the liquid-phase catalytic fluorination method is antimony pentachloride catalyst, which will be deactivated during the production process and will be discharged as a waste catalyst. The composition of spent fluorination catalysts is complex, mainly composed of antimony halides, halogenated hydrocarbons, hydrogen chloride, and hydrofluoric acid. It has a great impact on the environment and is a hazardous waste that must be disposed of properly or comprehensively utilized. [0003] Spent fluorination catalysts contain high concentrations of antimony, but antimony is less in natural reserves, so it has high resource value. Chinese Patent Publication...

AI Technical Summary

Problems solved by technology

Chinese Patent Publication No. CN1733612A discloses a method for recovering antimony trioxide from spent antimony pentachloride catalysts. The application adopts vacuum distillation, inorganic matter extraction, organic matter extraction, iron powder reduction, neutralization, filtration, washing and drying processes , the process is relatively complicated, the iron consumption is large, and the whiteness of the obtained product antimony trioxide is not ideal

[0004] Chinese Patent Publication No. CN101205571A adopts hydrochloric acid extraction, aluminum or zinc reduction, washing, filtration and drying to obtain metal antimony. Although the process is simple, the consumption of metal and the amount of waste acid produced are large due to the reduction in a strong acid system, and the amount of waste acid generated due to replacement is large. Metal antimony has high activity, and high-purity elemental antimony cannot be obtained, and some antimony oxides exist, so the application range is limited

[0005] Chinese Patent Publication No. CN102220496A discloses a method for recovering antimony pentoxide from waste antimony pentachloride catalysts, using water or washing water extraction, hydrogen peroxide oxidation, and industrial water hydrolysis to obtain water-containing antimony pentoxide. The method is simple in process and low in material consumption. , the discharge of the three wastes is small, but the antimony hydrolysis yield is 94% under the optimal conditions, and the antimony brought into the wastewater is relatively large

The technology is complicated, especially for SbCl 3 Distillation has high requirements on equipment and operation, and will also produce a large amount of waste hydrochloric acid