粉煤灰改性制备多金属复合材料及其对磷的去除研究

Preparation of polymetallic composites through modifying fly ash and its removal ability to phosphorus

以粉煤灰(FA)为原料,通过NaOH熔融改性制备具有大比表面积和介孔结构的多金属复合材料。考察了溶液pH、吸附剂用量、接触时间、磷初始浓度等因素对复合材料吸附水体中磷的影响。结果表明,基于粉煤灰制备的复合材料在酸性条件下对磷酸盐有着良好的吸附效果,接触30 min内即可达到吸附平衡,最大吸附容量高达51.61 mg/g,比原粉煤灰的吸附容量提升约16倍。复合材料对磷的吸附主要通过静电吸引作用,吸附过程符合准二级动力学模型,热力学符合Langmuir模型。

Polymetallic composites with high surface area and mesopores structure are prepared through roasting fly ash with NaOH.Moreover,the effects of solution pH,adsorbent dosage,contact time and initial concentration of phosphorus on the adsorption of the polymetallic composites to phosphorus in water are investigated systematically.It is indicated by the results that the prepared composites exhibit high adsorption efficiency for phosphates in acidic conditions,the adsorption equilibrium can be reached within 30 minutes of contact time and the maximum adsorption capacity of the composites is 51.61 mg·g^(-1),which is 16 times that of raw fly ash.The composites mainly adsorb phosphate ions via electrostatic attraction,and the adsorption process perfectly follows the pseudo-second-order kinetic model and Langmuir isotherm.