Selishchev Dmitry, Kozlov Denis
Boreskov Institute of Catalysis, pr. Ak. Lavrentieva 5, Novosibirsk 630090, Russia.
Molecules. 2014 Dec 19;19(12):21424-41. doi: 10.3390/molecules191221424.
Composite TiO2/activated carbon (TiO2/AC) and TiO2/SiO2 photocatalysts with TiO2 contents in the 10 to 80 wt. % range were synthesized by the TiOSO4 thermal hydrolysis method and characterized by AES, BET, X-ray diffraction and FT-IR ATR methods. All TiO2 samples were in the anatase form, with a primary crystallite size of about 11 nm. The photocatalytic activities of the TiO2/AC and TiO2/SiO2 samples were tested in the gas-phase photocatalytic oxidation (PCO) reaction of diethyl sulfide (DES) vapor in a static reactor by the FT-IR in situ method. Acetaldehyde, formic acid, ethylene and SO2 were registered as the intermediate products which finally were completely oxidized to the final oxidation products - H2O, CO2, CO and SO42- ions. The influence of the support on the kinetics of DES PCO and on the TiO2/AC and TiO2/SiO2 samples' stability during three long-term DES PCO cycles was investigated. The highest PCO rate was observed for TiO2/SiO2 photocatalysts. To evaluate the activity of photocatalysts the turnover frequency values (TOF) were calculated for three photocatalysts (TiO2, TiO2/AC and TiO2/SiO2) for the same amount of mineralized DES. It was demonstrated that the TOF value for composite TiO2/SiO2 photocatalysts was 3.5 times higher than for pure TiO2.
采用硫酸氧钛热水解法合成了TiO₂含量在10至80 wt.%范围内的复合TiO₂/活性炭（TiO₂/AC）和TiO₂/SiO₂光催化剂，并通过俄歇电子能谱（AES）、比表面积测定（BET）、X射线衍射（XRD）和傅里叶变换红外衰减全反射（FT-IR ATR）方法对其进行了表征。所有TiO₂样品均为锐钛矿型，初级晶粒尺寸约为11 nm。通过傅里叶变换红外原位法在静态反应器中对TiO₂/AC和TiO₂/SiO₂样品在二乙硫醚（DES）蒸汽的气相光催化氧化（PCO）反应中的光催化活性进行了测试。检测到乙醛、甲酸、乙烯和SO₂作为中间产物，最终它们被完全氧化为最终氧化产物——H₂O、CO₂、CO和SO₄²⁻离子。研究了载体对DES光催化氧化动力学以及TiO₂/AC和TiO₂/SiO₂样品在三个长期DES光催化氧化循环过程中的稳定性的影响。观察到TiO₂/SiO₂光催化剂的PCO速率最高。为了评估光催化剂的活性，针对相同矿化量的DES，计算了三种光催化剂（TiO₂、TiO₂/AC和TiO₂/SiO₂）的转化频率值（TOF）。结果表明，复合TiO₂/SiO₂光催化剂的TOF值比纯TiO₂高3.5倍。
