Stabilization of sodium dithionite by means of various additives

US10850982B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Eberhard Beckmann · Neustadt, DE
• Sabine Weiguny · Freinsheim, DE
• Martin Gärtner · Worms, DE
• Katharina FEDERSEL · Heidelberg, DE

Key dates

• Filing date: Apr 19, 2016
• Grant date: Dec 1, 2020
• Expiry date: Jul 6, 2036

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D21C9/1089
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

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.