响应面分析法优化木材微波液化的工艺研究

Optimization of Wood Liquefaction Using Microwave Heating with Response Surface Methodology

以醇解的聚对苯二甲酸乙二酯(PET)饮料瓶为液化剂,甘油为辅助液化剂,微波辅助加热,用2.5%H2SO4催化液化木材。采用Design-Expert7.1软件对木粉微波液化试验进行了方案设计和试验结果分析。选取液化温度、液化时间、液固比和微波辐射加热功率等四个因素进行中心组合设计;运用响应面法对木材微波液化工艺参数进行优化,得到了综合液化率与试验影响因素之间的定量数学关系模型,以及各个单因素和交互作用对液化率的影响结果,给出了木粉液化率的残差分布以及不同操作变量之间的综合液化率等值线和三维关系。木粉的微波液化实验最优条件为:反应时间10.51min,液固质量比3.93,液化温度154.7℃,微波辅助加热功率3.71kW,该条件下能使木粉完全液化。

Microwave radiation was used as the sole heating source; Liquefacient was prepared by alcoholysis of polyester （PET）, glycerol as the ancillary reagent; the ratio of liquefaction solvent 2.5% H2SO was used acid catalyst to achieve liquefaction of wood. The experiment plan of wood liquefaction was designed and its result was analyzed using Design-Expert 7.1 software. The effects of temperature, reaction time, liquid-solid rate and microwave radiation power were investigated by a four level three-factor Box-Behnken design. The preparation technique parameters were optimized with response surface method. The evaluation method of the rate of wood liquefaction is discussed, and a relation model of general rate of wood liquefaction with different operating variables for wood liquefaction test is established. The influence level of experimental single and interaction factors were compared by surface analyst result. Normal probability plot of residual for wood liquefaction ratio （WLR） and response surface and contours for desirability function of WLR with different factors are given in this paper. The optimum condition of wood liquefaction using microwave heating that was, reaction time 10.51 min, liquid-solid rate 3.93, temperature 154.7℃ and microwave radiation power 3.71 kW was obtained.