盐酸改性松木屑生物炭吸附海洋溢油的模拟研究

Study on adsorption of marine oil spill by hydrochloric acid modified pine sawdust biochar

海洋石油开采和运输过程中发生的溢油事故会对周边海洋生态环境造成严重威胁。以松木屑为原料,分别在300℃、400℃和500℃条件下,热解2 h制备生物炭,然后用盐酸对其改性,分析了改性前后生物炭对海水中石油的吸附性能。结果表明,热解温度和盐酸浓度对生物炭吸油性能的影响较显著,当热解温度为400℃、盐酸浓度为5 mol/L时生物炭对海水中石油的吸附量最大,达到1.96 g/g;改性后的生物炭比表面积和总孔容减小,表面官能团种类未发生明显改变,含氧官能团数量减少;改性生物炭对海水中石油的吸附符合准二级动力学方程(R^(2)=0.998)和Freundlich等温模型(R^(2)>0.999)。研究结果将有助于开发经济、环保和除油效率高的海洋溢油吸附材料。

Oil spill accident in the processes of marine oil exploitation and transportation will pose serious threats to the marine ecological environment. In this study, biochar was prepared from pine sawdust under pyrolysis temperature of 300 ℃, 400 ℃ and 500 ℃ respectively for 2 h, and then modified with hydrochloric acid. The oil adsorption properties of the biochar from seawater before and after modification were analyzed.The results showed that pyrolysis temperature and hydrochloric acid concentration had obvious effects on the oil absorption performance of biochar, and the adsorption amount of pine sawdust biochar was the largest at pyrolysis temperature of 400 ℃ and hydrochloric acid of 5 mol/L, which was 1.96 g/g. After modification, the specific surface area, total pore volume of the modified biochar and the number of oxygen-containing functional groups decreased, but the types of surface functional groups changed little. The oil adsorption process of modified biochar from seawater was in accordance with the pseudo second order kinetic equation(R^(2)=0.998)and Freundlich isotherm model( R^(2)>0.999). The results were helpful for the development of economical,environmental friendly and efficient adsorption materials for the treatment of marine oil spill.