Sodium sulfite

About: Sodium sulfite is a research topic. Over the lifetime, 2548 publications have been published within this topic receiving 18523 citations. The topic is also known as: Na2SO3 & Anhydrous sodium sulfite.

Production of p-toluenesulfonylacetic acid

Abstract: PURPOSE:To obtain the subject compound in high yield by preparing an aqueous solution of sodium p-toluenesulfinate as an intermediate from inexpensive p- toluenesulfonyl chloride as a starting raw material and adjusting pH with a base and/or adding an iodide during reaction with chloroacetic acid CONSTITUTION:For example, sodium sulfite and a base are dissolved or suspended in water and reacted with sodium p-toluenesulfonyl chloride to give an aqueous solution of sodium p-toluenesulfinate as an intermediate raw material In reacting the aqueous solution with chloroacetic acid, the reaction solution is adjusted to pH10-40 with a base such as sodium hydroxide and/or an iodide such as lithium iodide or sodium iodide (preferably about 002-006mol based on 10mol sodium p-toluenesulfinate) to give p-toluenesulfonylacetic acid in high yield p-Toluenesulfonylacetic acid is useful as an intermediate raw material for diiodomethyl-p-tolylsulfone suitable as industrial germicide and fungicide

Study of taking modified lignosulfonate as dye dispersant modification condition

Abstract: The invention relates to a study of taking modified lignosulfonate as a dye dispersant modification condition. According to the study, alkali lignin in papermaking waste liquid is taken as a raw material; the alkali lignin is modified by sulfonating condensation and sulfomethylation under a high-temperature alkaline condition, and then the optimal condition of modifying the dispersant with the lignosulfonate is determined. The system is composed of the following components: 50-100 parts of lignosulfonate, 100-300 parts of deionized water, 30-80 parts of sodium sulfite, 30% of sodium hydroxide aqueous solution and 30% of hydrochloric acid solution, and 40-80 parts of formaldehyde. The specific operating method comprises the following steps: adding the lignosulfonate, the deionized water and sodium sulfite in the mass ratio to a three-neck flask, regulating the temperature and the pH of the system to the conditions, and stirring at a constant temperature for sulfonation for 2-4 hours; after the sulfonation is ended, regulating the temperature of the system, adding formaldehyde in the proportion, regulating the pH, stirring at a constant temperature for 2-6 hours, and cooling to a room temperature, thereby obtaining the modified dispersant.

Foaming Prevention in Absorption Columns through Removal of Contaminants from Amine-Based Solutions Using a Solvent Resistant Nanofiltration (SRNF) Membrane

Abstract: An environmentally friendly removal method based on a membrane process for the purification of aqueous amine solution for use in carbon dioxide absorption was analyzed. Two kinds of commercial solvent resistant nanofiltration (SRNF) membranes (Desal-DL and SR100, polymeric) were chosen, and their capabilities in removing three common contaminants from diethanolamine (DEA) solution were examined. These contaminants that caused foaming of DEA solution include sodium chloride, sodium sulfite, and acetic acid. From the two tested solvent resistant nanofiltration (SRNF) membranes, it had been found that Desal-DL membrane provided promising results and performance that can be an alternative to conventional separation, including distillation, for purification of amine solution. Experiments were also conducted to test the foaming tendency and stability of the untreated and treated amine solution. The untreated DEA with sodium sulfite had the highest foaming tendency. However, after NF treatment, there was substan...

Effect of sodium sulfite on the dissolution of amorphous silica in aqueous solution

Abstract: 10－3～10－1 M（M＝mol dm－3）の低濃度範囲で，Na2SO3水溶液中での非晶質シリカの溶解速度及び溶解度を求め，純水及びNa＋濃度が等しくなるように調製したNaCl水溶液中での測定値と比較した．非晶質シリカの初期（0～12時間）溶解速度は，陽イオンであるNa＋によって速められたが，陰イオンであるCl－やSO32－にはほとんど影響されなかった．非晶質シリカの溶解度については，NaCl水溶液中では純水中とほぼ同じであったが，Na2SO3水溶液中では溶解度が増加した．増加した原因は，SO32－とケイ酸との錯体生成と考えられる．1 : 1錯体の生成を仮定し，Na2SO3とNaCl水溶液中でのシリカの溶解度の差に基づいて見積もられた条件付き生成定数は，pH 6.7～4.7の範囲で105～1951 M－1であった．

A process for producing silica, sodium sulfite and sodium hydrogen sulfite with sodium sulfate

Abstract: The present invention provides a process for producing silica, sodium sulfite and sodium hydrogen sulfite with sodium sulfate, wherein quartz sand, sodium sulfate and carbon are mixed and charged into a furnace for reaction and the obtained solid sodium silicate and sulfur dioxide are used to prepare silica, sodium sulfite and sodium hydrogen sulfite according to the following steps: 1) To produce silica: said solid sodium silicate is dissolved in water and filtered to produce a water glass solution; then sulfuric acid is reacted with said water glass solution to produce precipitated silica and sodium sulfate; and the precipitated silica is washed, filtered, liquefied and dried to produce silica; 2) To produce sodium sulfite: soda is added into a sodium hydrogen sulfite solution to produce sodium sulfite solution; one part of said sodium sulfite solution is concentrated and evaporated to obtain dry sodium sulfite; and the other part of the sodium sulfite solution is reacted with the sulfur dioxide produced during the production of the sodium silicate to produce sodium hydrogen sulfite solution, which can be recycled and reused in step (2); 3) To produce sodium hydrogen sulfite: soda is added into a sodium hydrogen sulfite solution followed by reacting with the sulfur dioxide produced during the production of the sodium silicate to produce a supersaturated sodium hydrogen sulfite solution, which is crystallized and dried to obtain a dry solid sodium hydrogen sulfite. The process of the present invention produces various products at low production cost and without causing environmental problems, and thus it has great practical value.