麦草碱木素磺化工艺及其性能研究

以麦草碱木素为原料,采用氧化磺化法,制备了磺化碱木素减水剂.采用正交实验优化了改性工艺条件:氧化剂用量为10%,磺化剂用量为26%,催化剂用量为0.8%,过硫酸钠用量为3.2%, pH 值9.5,总反应时间3.5 h.研究结果表明,水泥净浆中掺磺化碱木素后流动度显著增大,在0.3%掺量下,掺磺化碱木素的砂浆28 d抗压强度比达到118%,而掺木素磺酸钙的仅为98%.说明磺化碱木素的减水增强作用比木素磺酸钙强.

Preparation of Lignosulfonate Water Reducer from Wheat Straw Alkali Lignin

The lignosulfonate water reducing agent was prepared via oxidation and sulfonation of wheat straw alkali lignin.By studying the effects of oxidizer, pH,sulfonating agent,catalyst and reaction time on sulfonation reaction,the optimum reaction conditions were decided as the follows: charge of oxidizer 10%, dosage of sulfonating agent 26%,charge of catalyst 0.8%,sodium persulfate 3.2%,pH value about 9.5 and reaction time about 3.5 hours.It was found that the flowability of the cement mortar blended with sulfonated alkali lignin(SL) was improved obviously and the effect of sulfonated alkali lignin was better than calcium lignosulfonate;at 0.3% charge of the water reducing agent,28 days compressive strength of the mortar blended with SL reached 118% while blended with calcium lignosulfonation was only 98%.It indicated that the water reducing performance and compressive strength improvement of SL were better than that of calcium lignosulfonate.