不溶性腐植酸的制备及其吸附能力

The preparation of insoluble humic acid and its adsorption capacity

摘要:

采用陕西黄陵风化煤中提取的腐植酸为原料，选取保温温度和保温时间为变量，利用高温脱水钙化法制备出不同条件下的不溶性腐植酸. 实验结果表明当改性的腐植酸保温时间为2 h，保温温度为330 ℃时，吸附效果最佳，最佳条件下制备的不溶性腐植酸对水体中Cu2+的吸附量为8.87 mg/g，对亚甲基蓝吸附效率达98.8%. 腐植酸的碘吸附值158.4 mg/g，而最佳制备条件下的不溶性的腐植酸比表面积增加，微孔吸附能力增强，碘吸附值可达262.9 mg/g. 扫描电子显微镜（SEM）分析可以看出不溶性腐植酸表面更加粗糙，并负载了许多球状小颗粒，有助于提高吸附能力；傅里叶变换红外光谱（FTIR）分析表明不溶性腐植酸结构中羟基和有机卤化物的含量明显增高，有利于对重金属离子和有机污染物的吸附.

Abstract:

The humic acid which is extracted from Huangling, Shaanxi province is used as material. The temperature and the holding time are selected as variables. The insoluble humic acids under different conditions are prepared by high temperature dehydration calcification method. The experimental results show that the adsorption effect is the best when the modified humic acid holding time is 2 h and the holding temperature is 330 ℃. Under the optimum conditions, the adsorption amount of insoluble humic acid on Cu2+ ions in water is 8.87 mg/g and the adsorption rate of methylene blue is 98.8%.The iodine adsorption value of humic acid is 158.4 mg/g. The insoluble humic acid BET (the abbreviation of three scientists whose name are Brunauer、Emmett and Teller) surface area and microporous adsorption capacity under the best preparation condition are increased, so the iodine adsorption value of insoluble humic acid is 262.9 mg/g. SEM analysis shows that the surface of insoluble humic acid is rougher and is loaded with many spherical small particles, which could improve the adsorption capacity obviously. FTIR analysis shows that the contents of hydroxyl and organic halides in the insoluble humic acid structure are increased obviously. It is beneficial to the adsorption of heavy metal ions and organic pollutants.