In order to obtain porous nano CeO2 (cerium oxide),starch and Ce(NO3)3·6H2O were employed as a biotemplate agent and cerium source,respectively. The porous nano CeO2 was synthesized under mild conditions. Subsequently,the influence of calcination temperature and dosage of alkali and Ce(NO3)3·6H2O on the morphology of the porous nano CeO2 were investigated. The synthesized CeO2 was characterized by X-ray diffraction (XRD),N2 adsorption-desorption,and scanning electron microscopy (SEM). Furthermore, the catalytic performance was studied through the treatment of acrylic fiber wastewater by a catalytic wet peroxide oxidation method. The results indicated that: (1) The nano CeO2 had a porous structure and with pore size between 2-4 nm,pore volume of 0. 225 cm3/g and BET surface area of 256. 426 m2/g. (2) The optimum conditions for the preparation of the porous nano CeO2 were: dissolution of 1 g starch in 20 mL water followed by addition of 0.02 mol Ce(NO3)3·6H2O; pH adjustment of the precursor mixture using an aqueous solution of ammonia (5％); and calcination at 400 ℃ for 4 h with the heating rate of 1℃/min in air. A nano CeO2 with cavernous porous structure was obtained. (3) CeO2 with different morphologies was used as catalyst in wet catalytic reactions for degrading refractory organic matters in acrylic wastewaters. The best catalytic efficiency was obtained with the prepared porous nano CeO2,and the removal rate of CODCr reached 82.5％. In conclusion,the morphology of the CeO2 was affected by the calcination temperature and dosage of alkali and Ce(NO3)3·6H2O. This porous nano CeO2 can be used as an effective catalyst for treatment of acrylic wastewaters in wet catalytic peroxidation processes. The removal efficiency of CODCr could be significantly improved.%为获得多孔纳米CeO2(氧化铈),以淀粉为生物模板,以Ce(NO3)3·6H2O为铈源,在温和条件下制备出海绵状的多孔纳米CeO2,同时考察了焙烧温度、碱液、铈源投加量对样品形貌的影响.利用XRD (X射线衍射光谱)、SEM (扫描电镜)、N2吸附-脱附等表征手段对合成的多孔纳米CeO2进行物相组成、微观形貌及孔径大小分布的分析.通过湿式催化过氧化试验,探究其对腈纶废水中有机物CODCr的催化降解性能.结果表明:①所制备的多孔纳米CeO2具有多孔结构,孔径分布范围为2～4 nm,孔容为0. 225 cm3 /g,BET比表面积为256. 426 m2 /g;②多孔纳米CeO2的最佳制备条件为1 g淀粉溶解于20 mL水中,加入0. 02 molCe(NO3)3·6H2O,以5％的氨水调节前驱体混合液pH,以1 ℃/min升至400 ℃,焙烧4 h,得到海绵状的多孔纳米CeO2. ③以不同形貌的CeO2作为湿式催化反应中的催化剂,催化降解腈纶废水中有机物,其中以制备的多孔纳米CeO2催化性能最佳,CODCr去除率可达82. 5％.研究显示,焙烧温度、碱液、铈源投加量均可影响样品的形貌,在湿式催化过氧化处理腈纶废水试验中,多孔纳米CeO2能显著提高废水CODCr的去除率.
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