响应曲面法优化昭通褐煤制备农业腐植酸钾

Simulation-optimization for preparation of agricultural potassium humate from Zhaotong lignite by using response surface methodology

腐植酸钾是以泥炭、褐煤或风化煤等为原料与氢氧化钾反应而生成的一种新型钾肥,在改良和修复土壤、刺激作物根系发育、提高作物产量以及改善作物品质等方面具有重要作用。利用昭通褐煤制备了腐植酸钾,以腐植酸钾产率为目标,考察了KOH浓度、反应时间、反应温度对腐植酸钾产率的影响。利用响应曲面法中的Box-behnken Design方法优化了昭通褐煤制备腐植酸钾的工艺,得到较优的数学函数模型,并使用此函数模型推断了昭通褐煤制备腐植酸钾的最优工艺条件为:KOH浓度为0. 485 mol/L、反应时间为2. 10 h、反应温度为100℃,此时腐植酸钾产率为56. 60%。在优化条件下再次进行实验,得到的腐植酸钾产率为56. 58%,与函数模型预测值相吻合。

Potassium humate is a new type of potash fertilizer produced through potassium hydroxide reacting with peat,lignite or weathered coal.It plays an important role in improving and repairing soil,stimulating crop root to grow,increasing crop yield,and improving crop quality. In this study,Zhaotong lignite is used to produce potassium humate.Taking the yield of potassium humate as the evaluation target,the effects of KOH concentration,reaction time and reaction temperature on the yield of potassium humate are investigated. Box-behnken Design in Response Surface Methodology is utilized to optimize the preparation conditions of potassium humate from Zhaotong lignite,and a good mathematical function model is obtained. The optimal process conditions for the preparation of potassium humate from Zhaotong lignite are inferred by using this model.It is concluded that the yield of potassium humate is simulated to reach 56. 60% under the optimized operation parameters that KOH concentration is 0. 485 mol·L-1,the reaction lasts for 2. 10 h,and the reaction temperature maintains at 100℃ . The experiment is again carried out under the optimized parameters,in which potassium humate yield reaches 56. 58%,showing a good agreement with the simulation value.