造纸污泥制备功能吸附材料及其对Cu2+吸附性能的研究

Study on the preparation of functional adsorption material from paper sludge and its adsorption properties for Cu2+

以造纸污泥为原料,利用热解的方法制备生物炭,然后用氢氧化钠对其改性,得到功能吸附材料(SAM),探讨了SAM对Cu^2+的吸附性能及其影响因素。采用扫描电镜(SEM)、红外光谱等手段揭示了SAM吸附Cu^2+的机理。结果表明:造纸污泥在300℃热解2h,然后用5mol/L的氢氧化钠改性,可制备得到对重金属具有良好吸附性能的SAM;当100mg/L的Cu^2+模拟废水的pH为6~7时,SAM投加量为0.010 0g/mL下Cu^2+去除率为99.15%,SAM投加量为0.002 5g/mL下SAM的吸附量为28.788mg/g;SAM吸附Cu^2+符合Langmuir吸附等温模型,属于单分子层吸附,其吸附机理主要表现为化学吸附,即SAM中含有丰富的羟基官能团,Cu^2+能与羟基形成稳定的络合物,通过化学键固定在SAM的表面及孔内,从而达到去除模拟废水中Cu^2+的效果。

Using paper sludge as raw material,biochar was prepared by pyrolysis method,and then modified with NaOH to obtain functional adsorption material(SAM).The adsorption performance and influencing factors of SAM on Cu^2+were discussed.The mechanism of SAM adsorption on Cu^2+was revealed by means of SEM and infrared spectroscopy.The results showed that the paper sludge was pyrolyzed at 300℃for 2h,and then modified with 5mol/L NaOH to prepare SAM with good adsorption performance for heavy metals.When the pH of 100mg/L Cu^2+simulated wastewate was 6-7,the dosage of SAM was 0.010 0g/mL,the removal rate of Cu^2+was 99.15%,the dosage of SAM was 0.002 5g/mL,the adsorption capacity of SAM was 28.788mg/g;the adsorption of Cu^2+by SAM conformed to the Langmuir equation and belonged to monolayer adsorption,the adsorption mechanism was mainly characterized by chemical adsorption,SAM was rich in hydroxyl functional groups,Cu^2+could form a stable complex with hydroxyl groups,and was fixed on the surface and pores of SAM by chemical bonds,thereby achieving the effect of removing Cu^2+in simulated wastewater.