发明授权
- 专利标题: Method for producing sodium dithionite
- 专利标题(中): 生产连二亚硫酸钠的方法
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申请号: US11666973申请日: 2005-11-03
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公开(公告)号: US07968076B2公开(公告)日: 2011-06-28
- 发明人: Armin Diefenbacher , Hartwig Voss , Reinhard Schneider
- 申请人: Armin Diefenbacher , Hartwig Voss , Reinhard Schneider
- 申请人地址: DE Ludwigshafen
- 专利权人: BASF SE
- 当前专利权人: BASF SE
- 当前专利权人地址: DE Ludwigshafen
- 代理机构: Connolly Bove Lodge & Hutz LLP
- 优先权: DE102004053090 20041103
- 国际申请: PCT/EP2005/011786 WO 20051103
- 国际公布: WO2006/048293 WO 20060511
- 主分类号: C01B17/66
- IPC分类号: C01B17/66
摘要:
The invention relates to a process for the preparation of sodium dithionite, comprising the steps (a) provision of a synthesis batch comprising sodium formate, sulfur dioxide and an alkaline sodium compound in aqueous methanolic solution with formation of a sodium dithionite mother liquor, (b) isolation of sodium dithionite from the sodium dithionite mother liquor, a residual mother liquor being obtained, (c) separation of methanol from the residual mother liquor, (d) separation of the residual mother liquor into a thiosulfate-rich first part-stream and a thiosulfate-poor, formate-containing second part-stream by means of nanofiltration, (e) concentration of sodium formate in the second part-stream and (f) recycling of the concentrated second part-stream to process step (a).
公开/授权文献
- US20080187484A1 Method for Producing Sodium Dithionite 公开/授权日:2008-08-07