玉米芯基生物炭的制备及其吸附性能

采用农业废弃物玉米芯作为原材料,通过生物碳化(HTC)的方法在不同温度下制备低成本、高性能吸附剂用生物炭.该生物炭具有介孔结构,表面含有丰富的含氧官能团,如—OH,C==O,C—O等,其种类及密度受水热温度的影响.以亚甲基蓝(MB)作为模型吸附剂,进一步研究了生物炭的吸附性能.吸附动力学研究表明符合拟二级动力学模型吸附行为,且225 ℃水热条件下得到的生物炭具有最大吸附量(41.37 mg/g)和最高吸附速率.等温吸附平衡数据与Langmuir等温模型吻合较好,表明生物炭对MB的吸附是单层吸附;生物炭表面含氧官能团与MB分子相互作用有助于吸附过程.

Preparation and adsorption properties of corncob based biochar

Using agricultural waste corncob as raw material, biochar with low cost and high performance was prepared by hydrothermal carbonization (HTC) at different temperatures. The biochar has mesoporous structure and abundant oxygen-containing functional groups on its surface, such as —OH, C ==O, C—O and so on. Methylene blue (MB) was used as model adsorbent to further study the adsorption properties of the biochar. Results from the study of adsorption kinetics show that the adsorption behavior is in accordance with the pseudo second-order kinetics model, and the biochar obtained under the hydrothermal condition of 225 ℃ has the maximum adsorption capacity (41.37 mg/g) and the maximum adsorption rate. The adsorption equilibrium data agree well with the Langmuir isotherm model, indicating that the adsorption of MB on biochar belongs to monolayer adsorption, and the interaction between oxygen-containing functional groups on the surface of the biochar and the MB molecule is helpful to the adsorption process.