Ce/Fe/粉煤灰复合吸附材料的制备和表征

摘要

粉煤灰(FA)经HCl处理并通过沉淀焙烧法制备了一种新型Ce/Fe/FA复合材料,采用SEM、XRD、EDS、FT-IR及N2气吸附脱附技术进行了表征,并以直接桃红12B(DP 12B)和直接蓝2B(DB 2B)染料为吸附对象,考察了材料的制备条件和工艺参数.结果表明,FA用4 mol/L HCl于80 ℃处理60 min后加入一定浓度FeCl3·6H2O与Ce(SO4)2·4H2O混合溶液(三者质量比为160∶4∶1),调节pH值为10,于40 ℃静置2 h后在300 ℃焙烧1 h即制得Ce/Fe/FA复合材料,对DP 12B和DB 2B具有最佳吸附效果,吸附量分别可达165.54和160.87 mg/g,比FA分别增大了6.26和7.81倍.表征结果说明铁铈氧化物成功负载于FA上,所得Ce/Fe/FA比表面积比FA增大了7.29倍,吸附性能显著增强,对高浓度直接染料废水可实现有效净化.%A novel cerium/ferrum/fly ash (Ce/Fe/FA) composite adsorbent was prepared by HCl treatment and precipitation-calcination method using FA as raw material, and characterized with XRD,SEM,EDS, FT-IR and N2 gas adsorption-desorption technique.The effects of preparing conditions and process parameters on the adsorption properties of Ce/Fe/FA for direct pink 12B (DP 12B) and direct blue 2B (DB 2B) dyes were investigated in detail.The results show that FA is modified by 4mol/L HCl at 80 ℃ for 60 min before adding the mixed solution of FeCl3·6H2O and Ce(SO4)2·4H2O[m(FA)∶m(FeCl3·6H2O)∶m(Ce(SO4)2·4H2O)=160∶4∶1], and then adjusted to pH=10.The Ce/Fe/FA composite adsorbent was prepared by standing the mixed solution at 40 ℃ for 2 h, drying and roasting at 300 ℃ for 1 h, and the obtained Ce/Fe/FA composite exhibits excellent adsorption performance for DP 12B and DB 2B with adsorption capacities of 165.54 and 160.87 mg/g, which are 6.26 and 7.81 times larger than those of FA.The characterization shows that the ferric oxide and cerium oxide are successfully loaded on the FA surface, and the surface morphology of Ce/Fe/FA has changed obviously compared with FA.Its specific surface area is 7.29 times larger than that of FA, and the adsorption capacity is significantly enhanced, which could be used for the effective purification of high-concentration direct dye wastewater.