中心复合设计法优化阳离子硫酸盐浆的制备工艺

Optimization of the Preparation of Cationic Kraft Pulp by Central Composite Design

以阳离子硫酸盐浆的表面电荷密度为评价指标,采用中心复合设计法对丙烯酰胺(AA)和甲基丙烯酰氧基乙基三甲基氯化铵(MAETMAC)接枝共聚制备阳离子硫酸盐浆的工艺进行了优化。研究结果表明,反应温度(X2)、MAETMAC摩尔分数(X3,占总单体)以及引发剂铈硝酸铵的量(X4)对评价指标有非常显著的影响(P<0.01),反应时间(X5)对评价指标有显著影响(P<0.1),而硝酸的浓度(X1)对评价指标无显著影响(P>0.1)。拟合所得多元二次方程为Y=816+87.13X2+79.54X3+91.71X4+36.88X5–53.44X1X4–68.76X22–51.89X32–71.39X42,相关系数R2=0.9090。当浆浓固定为10%,总单体的用量为10mmol/g浆时,制备阳离子硫酸盐浆优化工艺为:硝酸的浓度为0.002mol/L、反应温度为63℃、MAETMAC摩尔分数为65%、引发剂铈硝酸铵的量14.32%(占绝干浆)、反应时间为208min,该工艺得到的阳离子硫酸盐浆表面电荷密度为1055mmol/kg。通过验证实验表明,本优化方程有良好的预测性。

In this paper the surface charge density of cationic kraft pulp was chosen as response variable and the preparation conditions of cationic kraft pulp by the in-situ grafting copolymeration of acrylamide （AA） and cationic monomer, [2-（methacryloyloxy） ethyl] trimethyl-ammonium chloride （MAETMAC） were optimized by central composite design. The results showed that the reaction temperature （X2）, the molar percentage of MAETMAC on total monomers 0（3） and the amount of cerium （IV） ammonium nitrate （CAN） （X4） have very significant effect on the response （P〈0.01）, and reaction time 0（5） has significant effect （P〈0.1）, but the consistency of nitric acid has less significant effect （P〉0.1）. The secondorder polynomial equation is Y= 816 ＋ 87.13 X2＋ 79.54 X3 ＋ 91.71X4 ＋ 36.88 X5 - 53.44 X1X4 - 68.76 X2^2 - 51.89 3（32 - 71.39 X4^2, and the regression coefficient is R2 = 0.9090. When the consistency of pulp is 10%, and the amount of total monomers is 10 mmol/（g pulp）, the optimized conditions of preparation of cationic kraft pulp are： the consistency of nitric acid is 0.002 mol/L, reaction temperature is 63℃, molar percentage of MAETMAC is 65%, the amount of CAN is 14.32% （o.d basis）, and the reaction time is 208 rain, the cationic kraft pulp which the surface charge density is 1097 mmol/kg is obtained. It was showed that the equation can be used to predict the preparation condition of cationic kraft pulp.