发明授权
- 专利标题: Continuous process for complete removal or organic impurities from and complete decolorization of prepurified wet-process phosphoric acid
- 专利标题(中): 用于完全去除或有机杂质的连续方法和完全脱湿的湿法磷酸完全脱色
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申请号: US311640申请日: 1989-02-16
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公开(公告)号: US4906445A公开(公告)日: 1990-03-06
- 发明人: Gunther Schimmel , Gerhard Bettermann , Gero Heymer , Friedrich Kolkmann
- 申请人: Gunther Schimmel , Gerhard Bettermann , Gero Heymer , Friedrich Kolkmann
- 申请人地址: DEX Frankfurt am Main
- 专利权人: Hoechst Aktiengesellschaft
- 当前专利权人: Hoechst Aktiengesellschaft
- 当前专利权人地址: DEX Frankfurt am Main
- 优先权: DEX3806822 19880303
- 主分类号: C01B25/234
- IPC分类号: C01B25/234 ; C01B25/235 ; C01B25/46
摘要:
A continuous process is indicated for complete removal of organic impurities from and complete decolorization of pre-purified wet-process phosphoric acid which has been purified by an extractive method using an organic solvent, freed from residual hydrofluoric acid by steam stripping and treated with hydrogen peroxide at elevated temperature, which comprises mixing the pre-purified wet-process phosphoric acid and the hydrogen peroxide in a mixing zone at a temperature of from 100.degree. to 200.degree. C., preferably 140.degree. to 160.degree. C., and allowing them to react at this temperature for a further 1 to 4 hours, cooling to from 85.degree. to 90.degree. C. the pre-purified wet-process phosphoric acid treated in this way and pumping it at this temperature with exclusion of air firstly through an activated charcoal bed which has been prepared on the basis of peat and has been steam-activated and has a BET surface area of from 800 to 1000 m.sup.2 /g, and subsequently through a silicon carbide and/or graphite bed while maintaining a pumping rate of less than 0.5 m.sup.3 /h of wet-process phosphoric acid per m.sup.3 of activated charcoal bed.