基于响应面模型对花生壳基活性炭工艺的优化

为优化木质活性炭制备的工艺条件，以农林废弃物花生壳为原料，磷酸为主活化剂，硫酸为辅助活化剂，利用响应面模型分析磷酸质量分数、浸渍比(活化剂体积与花生壳质量比)、活化时间、活化温度对活性炭性能的影响。结果表明：通过Box-Behnken试验建立的二次多项式数学模型的P值都小于0.000 1，校正决定系数(R²)分别为0.990 2和0.997 8，变异系数(CV) < 10%，试验的可信度和精确度高，回归方程成立。通过二次回归模型得到磷酸-硫酸活化法制备花生壳基活性炭的最佳工艺条件为花生壳粉末1 g,磷酸质量分数57.7%，浸渍比2:1，活化时间117 min，活化温度550 ℃。在最佳工艺条件下，制备的活性炭亚甲基蓝吸附值为147.2 mg/g，碘吸附值1 022.03 mg/g，实际值与预测值接近，重复性好。利用磷酸-硫酸活化法制备的花生壳基活性炭的内部中小孔较发达，具有较强的吸附能力和脱附能力。

Optimization of Preparation Technology of Peanut Shell Based Activated Carbon by Response Surface Model

The process conditions of wood-based activated carbon were optimized by using agriculture and forestry waste, peanut shell, as raw material, phosphoric acid as activator and sulfuric acid as auxiliary activator. The impacts of phosphoric acid concentration, impregnation ratio(volume-mass ratio of activator to peanut shell), activation time, activation temperature on the properties of activated carbon were investigated by using the response surface methodology. The results showed that through Box-Behnken test data, the P value of mathematical model of quadratic polynomial on the methylene blue adsorption value and iodine adsorption value was less than 0.000 1, the correct determination coefficients(R²) were 0.990 2 and 0.997 8, respectively, reached extremely significant level; and CV was less than 10%, the experiment had most high credibility and accuracy, and the regression equation was established. The optical process conditions of using phosphoric acid-sulfuric acid activation method to prepare peanut shell based activated carbon were peanut shell powder 1 g, phosphoric acid mass fraction 57.7%, impregnation ratio 2:1, activation time 117 min and activation temperature 550 ℃. Under the conditions, the methylene blue adsorption value was 147.2 mg/g, the iodine adsorption value was 1 022.03 mg/g, which was close to the predicted values and had good repeatability, the inner hole of the peanut shell base activated carbon was more developed, the larger methylene blue adsorption value and the relatively small iodine adsorption value maked the activated carbon have stronger adsorption capacity and desorption capacity, the study of preparation mechanism of peanut shell activated carbon had laid a solid foundation.