Stabilization of sodium dithionite by means of various additives

    公开(公告)号:US10850982B2

    公开(公告)日:2020-12-01

    申请号:US15569792

    申请日:2016-04-19

    Applicant: BASF SE

    Abstract: The present invention relates to a method for reducing or preventing the decomposition of a composition Z comprising Z1 a salt of dithionous acid in an amount ranging from 50 to 100 wt % and optionally Z2 an additive selected from the group consisting of alkali metal carbonate, alkaline earth metal carbonate, alkali metal or alkaline earth metal tripolyphosphate (Na5P3O10), alkali metal or alkaline earth metal sulfite, disulfite or sulfate, dextrose and complexing agents in a combined amount ranging from 0.0001 to 40 wt %, which comprises contacting the components Z1 and optionally Z2 in the solid and/or dry or solvent-dissolved or -suspended state with at least one of the following compounds V in the solid and/or dry or solvent-dissolved or -suspended state, wherein the compounds V are selected from the group consisting of: (a) oxides of the alkali metals lithium, sodium, potassium, rubidium, cesium, or of magnesium, (b) sodium tetrahydroborate (NaBH4), (c) anhydrous copper(II) sulfate (Cu(SO4)), phosphorus pentoxide and (d) basic amino acids arginine, lysine, histidine, wherein the solvent for Z1, optionally Z2 and V is practically water-free.

    Method of reprocessing alkanesulfonic acid

    公开(公告)号:US10214485B2

    公开(公告)日:2019-02-26

    申请号:US15774722

    申请日:2016-11-08

    Applicant: BASF SE

    Abstract: The invention relates to a method of reprocessing alkanesulfonic acid employed in a chemical process as an agent, catalyst or solvent and comprising the steps of: (a) removing an alkanesulfonic acid-comprising stream from a reaction mixture generated in the chemical process, (b) feeding the alkanesulfonic acid-comprising stream into a melt crystallization as the starting melt to form crystals of the alkanesulfonic acid, of hydrates of the alkanesulfonic acid or of a mixture of both suspended in mother liquor, (c) performing a solid-liquid separation to remove the crystals from the mother liquor, (d) optionally washing the crystals to remove mother liquor adhering to the crystals, (e) recycling the washed or unwashed crystals removed from the mother liquor into the chemical process.

Patent Agency Ranking