US 2021/0047742 A1

Method of making alkali and gypsum by
proton-coupled electron transfer reaction

(22) 16.08.2019

(43) 18.02.2021

(57) The present disclosure provides a method for preparing an alkali and co-producing gypsum, and belongs to the technical field of chemical production. The method comprises the steps of placing a cation exchange membrane into an electrolytic cell, adding a solution of sodium salt of a weak acid and a compound MH to an anode region as an anode electrocatalyst, adding sodium carbonate or sodium hydroxide to a cathode region, adding a compound M as a cathode electrocatalyst, and applying a DC power supply between a cathode electrode and an anode electrode. The electrolysis oxidizes the MH into the M and releases H+, Na+ in the anolyte penetrates through the cation exchange membrane to reach a cathode region to be combined with OH- in the catholyte to generate NaOH, or further absorbs CO2 and converts into Na2CO3; the anolyte containing a large amount of H+ is generated by the electrolysis for dissolution reaction with limestone, and the H+ is consumed to generate Ca2+, and SO42- and Ca2+ are combined to generate high-purity CaSO4 precipitate. According to the present disclosure, a compound capable of generating PCET reaction is used as an electrocatalyst, while M is its oxidation state and MH is its reduction state, and mirabilite and limestone are used as raw materials to realize the preparation of soda ash, caustic soda and gypsum.

(71) Yufei Wang, Chongqing (CN); Tao Liu, Chongqing (CN)

x

Related articles:

Issue 2020-3 WO 2019/231229 A1

Method for preparing chemical gypsum having SO3 content of 38?% or greater (weight basis) by preparing alkali neutralizer using industrial byproducts containing steel slag or calcium oxide as major raw materials and neutralizing waste acid by dry method

(22) 29.05.2019 (43) 05.12.2019 (57) The present invention relates to a method for preparing chemical gypsum having a SO3 content of 38?% or greater by preparing an alkali neutralizer using, as major...

more
Issue 2018-7-8 KR101839251 (B1)

Alkali gypsum and method for producing alkaline gypsum using de-sulfurized slag admixture slagcement and concrete composition comprising the alkali gypsum

(22) 20.12.2016 (43) 26.04.2018 (57) The present invention relates to a method for producing an alkali gypsum for admixture of ordinary cement or slag cement using a desulfurized slag fine powder...

more
Issue 2018-11 EP3371100 (A1)

Method for reducing elemental sulfur in gypsum products

(22) 03.11.2016 (43) 12.09.2018 (57) Disclosed are various methods for reducing levels of elemental sulfur within gypsum products such as wall board. Gypsum sometimes includes increased levels of...

more
Issue 2017-7-8 WO 2017/079410 A1

Method for reducing elemental sulfur in gypsum products

(22) 03.11.2016 (43) 11.05.2017 (57) Disclosed are various methods for reducing levels of elemental sulfur within gypsum products such as wall board. Gypsum sometimes includes increased levels of...

more
Issue 2021-6 WO 2021/120705 A1

Method for preparing ?-hemihydrate gypsum

(22) 07.09.2020 (43) 24.06.2021 (57) Disclosed is a method for preparing ?-hemihydrate gypsum, the method involving using citric acid as a crystal transformation agent to prepare dihydrate gypsum, and...

more