钨掺杂TiO2可见光下去除阿替洛尔的反应特性

Reaction characteristics of atenolol removal using W-doped TiO2 particles under visible light

采用溶胶凝胶法制备了钨掺杂改性TiO2,以13WLED白灯(λ>420nm)模拟可见光光源,对阿替洛尔进行了光催化降解实验.考察了光源和溶液pH对阿替洛尔降解率的影响,并对光催化氧化阿替洛尔的反应机理进行了研究.结果表明,对TiO2进行钨掺杂改性可使其拥有良好的可见光响应,同时不影响其在紫外光辐照下的反应;阿替洛尔的降解率随溶液pH的升高先增大后减小,在碱性条件下阿替洛尔更容易降解;在光照360min时,阿替洛尔的降解率达93%,总有机碳(TOC)的降解率为64%,阿替洛尔在完全矿化前首先转化为中间产物;通过LC-MS技术推断出了阿替洛尔在光催化降解中的14种中间产物,并提出了降解途径可能包括醚支链的断裂、羟基化、形成苯甲醛衍生物、官能团的消除和分子间的环化与重组等.

To process the photocatalytic degradation of atenolol, both W-doped TiO 2 particles were made through a sol-gel method and a 13 W light-emitting diode lamp (λ>420 nm) was used as a visible light resource. The reaction mechanism of photocatalytic oxidation of atenolol was studied for investigating the influences of the light resource and the solution pH on the degradation rate of atenolol. Experimental results show that the W-doped TiO 2 particles have a good visible light response without affecting its reaction under ultraviolet light irradiation. The degradation rate of atenolol increases firstly, and then decreases with the pH increment. Atenolol is relatively easier to be degraded under the alkaline condition. The degradation rates of atenolol and total organic carbon(TOC) are 93% and 64%, respectively after 360 min visible light irradiation. Atenolol is converted into intermediate products before its complete mineralization. Fourteen intermediates in the photocatalytic degradation of atenolol are identified by a liquid chromatograph-mass spectrometer (LC-MS) technique and the possible degradation pathways includes the breakage of ether branched chains, hydroxylation, formation of benzaldehyde derivatives, elimination of functional groups, and intermolecular cyclization and recombination.