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Preparation method of water reducing agent

The sulfite waste liquor is neutralized with an alkaline solution, sugar is removed by biological fermentation, and evaporated and dried to form a powdery water-reducing agent. It uses the waste liquid from the production of chemical fiber pulp cypress made from the factory's sulfite cooking wood (more than 75% of which is white pine) as raw material. First, the alcohol is extracted through the biological fermentation treatment of sugar removal. The stored alcohol waste liquid of about 10% concentration is concentrated to about 50% through the evaporator, then sent to the spray for drying, and then dried by hot air at 200 ℃. Its pH=4.5-5.5. Different types of cooking materials and cooking processes significantly impact the chemical composition of sulfite pulp effluent and lignosulfonate produced, thereby affecting the performance of Water reducing agents. Alkaline or sulfate lignin is separated by acidification precipitation, then sulfonated to generate lignosulfonate in an alkaline medium. Lignin in alkali pulping black liquor exists in the form of alkali lignin. When the effective alkali content in the black liquor is more than 1.14%, the alkali lignin is wholly dissolved in the black liquor as a hydrophilic gel, and no precipitation occurs. When the effective alkali content is less than 0.71%, the alkali lignin colloid is partially damaged, resulting in rainfall. Due to the presence of hydrophilic groups in alkali lignin, the black liquor has specific activity, but the effect is unstable. Therefore, it is necessary to introduce anionic surface active groups such as sulfonic, amino, and carboxylic groups to modify the production of Water reducing agents from alkaline pulp waste. Lignin is prone to react with sulfonating agents such as sulfite and sulfite to form lignosulfonate. The reaction principle is as follows: Sulfurous acid is added to the enol group in the lignin molecule to introduce a sulfonic acid group. The reagent for introducing the sulfonic acid group is Na2S03. Due to the hydrolysis of Na2S03 to generate H2SO3, the addition reaction can be carried out to generate lignosulfonate in an alkaline medium. If you are looking for high quality, high purity and cost-effective water reducing agent, or if you require the latest price of water reducing agent, please feel free to email contact mis-asia.

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