摘要 |
Sulphite, and preferably sodium sulphite and sodium bisulphite, is used as absorbing agent for aldehydes at the production of paper. The sulphite is added to the stock or the process water in combination with a cationic retention agent, such as eg alum. A product suitable for use at the production of paper is an aqueous solution of a combination of sulphite and a cationic retention agent, preferably alum. |