光催化转化并回收水中农药有机磷

经溶胶-凝胶法制备不同镧（La）掺杂量的二氧化钛（TiO₂），得到光催化转化吸附回收有机磷的复合材料.结果表明，La与TiO₂掺杂物质的量比为0.002并经过煅烧和掺杂物质的量比为0.02未经煅烧的2种材料，以6：4的比例混合，所得复合材料La@TiO₂（6：4）为粒径约13nm的锐钛矿型TiO₂，表面有球形聚集体但分布较均匀，其光谱范围较纯TiO₂发生红移，因而光催化效率提高.当有机磷浓度20mg/L、La@TiO₂（6：4）投加量为1g/L、溶液pH值为9时，有机磷回收率最高达85%.溶液中的NO₃^-、Cl^-、SO₄^2-对磷回收影响不大，CO₃^2-有抑制作用；材料经解吸后可多次重复利用.研究表明La@TiO₂（6：4）为有前景的有机磷回收复合材料.

Photocatalytic conversion and recycle of organic phosphorus within pesticides form aqueous solution

Titanium dioxide (TiO₂) doped with different amounts of lanthanum (La) were prepared by using sol-gel method. The composite materials obtained can be photocatalyzed to convert and recover organic phosphorus. By mixing a calcined lanthanum-TiO₂ composite material with a molar ratio of 0.002 with that at a molar ratio of 0.02 without calcination at a weight ratio of 6:4, a composite material named La@TiO₂(6:4) was finally obtained. It had a crystal structure of anatase TiO₂ with a particle size of about 13nm, and had a surface withspherical aggregates which were uniformly distributed. The light utilization map range of this material was red-shifted as compared to pure TiO₂, which resulted in spectrum utilization range expansionthusphotocatalytic efficiency improvement. The phosphorus recovery was up to 85% when 1g/L La@TiO₂(6:4) dosage was employed at a initial organic phosphorus concentration of 20mg/L, and the pH of 9. No obvious effect of NO₃^-、Cl^- and SO₄^2- in solution on phosphorus recovery was observed, but CO₃^2- negatively affected the phosphorus recovery. The La@TiO₂(6:4) material can be reused for many times after desorption.The reaserch showed that La@TiO₂(6:4) is a promising organic phosphorus recycling composite.