微波辐照废木屑制备活性炭及处理甲基橙废水的研究

Study on Preparation of Activated Carbon from Waste Sawdust by Microwave Irradiation and Treatment of Methyl Orange Wastewater

摘要: 以常见的木材厂废木屑作为原料，通过微波辐照以Na₂CO₃为活化剂，制备废木屑活性炭。利用Design expert软件中水平设计和响应面分析法对微波条件下废木屑制备活性炭进行了优化，经过逐步回归分析建立了微波时间、木屑细度、固液比以及活化剂浓度对活性炭的产率和对甲基橙脱色力影响的二次回归模型。产率和脱色率的回归方程的决定系数分别达到了0.9866和0.9978。得到较优的碳化条件为：微波辐照时间8.02分钟、木屑细度40~60目、固液比1:1.5、活化剂浓度21.5%，该条件下废木屑活性炭的产率达到54.9%，对甲基橙的脱色率达到89.56%。微波辐照法制备活性炭，加热时间短，能耗低，是活性炭制备的绿色化学工艺，且实现变废为宝，可为废木屑的资源化处置提供一条合理的途径。

Abstract: Waste wood chips were prepared by microwave irradiation with Na₂CO₃ as activator. Based on the level design and response surface analysis method in Design expert software, the activated charcoal was prepared under microwave condition. The yield of activated carbon was determined by step-wise regression analysis. Through stepwise regression analysis, the two regression models were es-tablished for the effects of microwave time, sawdust fineness, solid-liquid ratio and activator con-centration on the yield of activated carbon and the decolorization capacity of methyl orange. The de-cisive coefficients of the regression equation were 0.9866 and 0.9978, respectively. The optimum conditions of carbonization were as follows: microwave irradiation time—8.02 min, sawdust fine-ness—40~60 mesh, solid-liquid ratio—1:1.5, activator concentration—21.5%, under which the yield of activated wood was 54.9%, the decolorization rate of methyl orange reached 89.56%. The preparation of activated carbon by microwave irradiation, with short heating time and low energy consumption, is a green chemical process made by activated carbon. It can also be used to save waste materials and provide a reasonable way for the waste wood sawdust to be disposed.