碳热法制备生物炭负载纳米零价铁材料去除对氯苯胺

Removal of P-chloroaniline by Zero-valent Iron Nanoparticles Supported by Biochar Prepared by Carbothermal Method

利用碳热法共热解花生壳生物质炭(BC)和九水合硝酸铁(Fe(NO_(3))_(3)·9H_(2)O)的混合物,制备了碳基零价铁(Fe/C_(x))复合材料。通过SEM、TEM、BET、XRD、FTIR、XPS等对其进行表征分析,探究了铁掺杂量、Fe/C_(x)复合材料投加量、溶液初始浓度、pH等对对氯苯胺去除效果的影响。结果表明Fe/C_(x)复合材料具有较大的比表面积(538.86 m^(2)/g)和孔容积(0.3172 cm^(3)/g),在生物质炭上负载了纳米零价铁(nZVI)和Fe_(3)O_(4)颗粒;PCA的吸附过程为单分子层吸附,符合伪二级动力学模型(R^(2)>0.98),吸附平衡时去除率达98.56%。Fe/C_(x)复合材料对PCA的去除机制可能包括表面吸附-孔隙填充作用,氢键作用,π-π相互作用和Fe^(0)的还原作用。

The carbon-based zero-valent iron(Fe/C_(x))composites were prepared by co-pyrolysis of peanut shell biochar(BC)and ferric nitrate nonahydrate(Fe(NO_(3))_(3)·9H_(2)O)mixture using the carbothermal method.The composites were characterized and analyzed by SEM,TEM,BET,XRD,FTIR,XPS,etc.And the effects of Fe doping amount,Fe/C_(x)composite injection,initial concentration of solution and pH on the removal effect of PCA were investigated.The results showed that Fe/C_(x)composites had a large specific surface area(538.86 m^(2)/g)and pore volume(0.3172 cm^(3)/g)and nano-zero-valent iron(nZVI)and Fe_(3)O_(4)were loaded on BC.The adsorption process of PCA was a single-molecular layer adsorption,and it conformed to the pseudo-secondary kinetic model(R^(2)>0.98),with a removal rate of 98.56%at adsorption equilibrium.The mechanisms of PCA removal by Fe/C_(x)composites may include surface adsorption-pore filling,hydrogen bonding,π-πinteractions and Fe^(0)reduction.