改性木质素磺酸盐减水剂的合成

以造纸黑液为原料,H2O2为氧化剂,Na2SO3为磺化剂,HCHO为羟甲基化试剂,经氧化、甲基化、磺化,合成了改性木质素磺酸盐减水剂,研究了反应温度、时间及药剂加入量对水泥净浆流动度的影响。结果表明,其最佳合成工艺条件为:氧化剂用量15%,反应温度80~90℃,时间1 h;甲醛用量30%,磺化反应温度95℃左右,时间3.5 h;pH值控制在9.5左右。在此条件下,改性木质素磺酸盐具有较好的减水性能,在掺量0.25%,水灰比0.4%的条件下,水泥净浆流动度可达到178 mm,已接近高效减水剂的减水性能。

Synthesis of water reducer of modified lignosulfonate

The water reducer of modified lignosulfonate was synthesizd using the black liquor as raw material,H2O2 as oxidant,Na2SO3 as sulfonating agent and HCHO as hydroxymethylation agent in the process of pre-oxidation,hydroxymethylation and sulfonation.The influence of reaction temperature,time and pharmaceutical dosage on fluidity of cement paste were investigated.The optimum technology conditions were obtained:the oxidizing agent dosage was 15%,reaction temperature was 80~90 ℃;the dosage of formaldehyde was 30%,reaction temperature was about 95 ℃,time was 3.5 h,pH was about 9.5.Fluidity of cement paste can be measured under the conditions of the addition of 0.25%,and the water-cement ratio of 0.4%.The results showed the performance of slushing for modified lignosulfonate prepared under the above conditions of which the fluidity of cement paste can reach 178 mm that is close to what the high efficiency water reducing agent reached was good.