混凝土负载C,N-TiO_2对有机磷杀虫剂的吸附和降解性能研究

Study on adsorption and degradation of organophosphorus pesticides by C and N-TiO_2 supported on concrete

本文制备了一种负载碳、氮共掺杂二氧化钛(C,N-TiO_2)的混凝土(C,N-TiO_2/Ct),研究了光催化剂负载量和固化时间对其吸附、降解敌百虫的影响,测试了混凝土的抗压强度和抗渗性能。结果表明,与普通混凝土(Ct)和TiO_2/混凝土(TiO_2/Ct)相比,C,N-TiO_2/Ct对敌百虫有较高的降解效率,并随着C,N-TiO_2的增加而逐渐提高,但其吸附效率却相对较低。混凝土对敌百虫的降解和吸附效率随固化时间的增加而降低,固化3 d的5%C,N-TiO_2/Ct吸附率比Ct低8.8%,但对敌百虫的降解率比Ct高15.4%。此外,混凝土的抗压强度随催化剂含量和固化时间的增加而提高,固化28 d的5%C,N-TiO_2/Ct的抗压强度与Ct相比提高了24.8%。混凝土的抗渗性能随着C,N-TiO_2含量的增加呈先升高后降低的趋势,其中2.5%C,N-TiO_2/Ct抗渗性能最高,比Ct增加了36.2%。因此,光催化混凝土具有控制河流面源污染的应用潜力。

A kind of concrete （C, N-TiO2/Ct） loaded with carbon and nitrogen co-doped titanium dioxide （C, N-TiO2） was prepared. The effects of photocatalyst loading and curing time on the adsorption and degradation of trichlorfon were studied, and the compressive strength and impermeability of concrete were tested. The results showed that compared with ordinary concrete （CO and TiOJ （TiO//C0, C concrete, N-TiO2/Ct had higher degradation efficiency on trichlorfon and gradually increased with the increase of C and N-TiO2, but its adsorption efficiency was relatively low. Concrete degradation and adsorption efficiency of trichlorfon decreased with increasing curing time, and the adsorption rate of 5% C, N-TiOJCt curing 3 days was 8.8% lower than Ct, but the rate of degradation of trichlorfon was 15.4% higher than Ct. In addition, the compressive strength of concrete increases with the increase of catalyst content and curing time, and the compressive strength of 5% C,N-TiO2/Ct increased by 24.8% compared with Ct after curing 28 days. The impermeability of concrete increased first and then decreased with the increase of C, N-TiO2 content, among which 2.5% C,N-TiOE/Ct had the highest impermeability, which was 36.2% higher than Ct. Therefore, photocatalytic concrete had the potential to control the non-point source pollution of rivers.