以水生植物凤眼莲为原料,采用一步浸渍-焙烧法制备了一种载镁生物炭复合材料并进行吸附实验。利用多种表征技术(SEM、EDS、XRD、FT-IR、BET)对载镁生物炭的结构和性质进行了分析,发现改性后的生物炭负载了大量的镁氧化物及氢氧化物。通过对比考察了pH、吸附温度、吸附时间、吸附剂投加量等因素对载镁生物炭吸附Cu²⁺、Pb²⁺的影响。结果表明,载镁生物炭对Cu²⁺、Pb²⁺的吸附效果远优于原始生物炭;pH对吸附行为有显著性的影响。载镁生物炭复合材料对Cu²⁺、Pb²⁺的吸附行为更符合准二级动力学模型,吸附等温线更符合Langmuir模型,通过热力学参数可知吸附反应为自发吸热过程。

A magnesium-loading biochar composite is prepared from water hyacinth by one-step impregnation-pyrolysis method,and is evaluated for adsorption test.Its structure and properties are characterized by means of multiple characterization techniques (SEM,EDS,XRD,FT-IR,BET),and it is revealed that the modified biochar loads with a large number of magnesium oxides and hydroxides.By force of contrast,the effects of pH,adsorption temperature,adsorption time and adsorbent dosage on the adsorption capacity of magnesium-loading biochar for Cu²⁺ and Pb²⁺ are investigated.It is shown that the adsorption effect of magnesium-loading biochar on Cu²⁺ and Pb²⁺ is much better than that of original biochar.The pH has a significant effect on the adsorption behavior.The adsorption behavior is more in line with the quasi second-order kinetic model,and the adsorption isotherm is more consistent with Langmuir model.It is found through thermodynamic parameters that the adsorption reaction belongs to a spontaneous endothermic process.