摘要
设计了新型气固相间歇循环式光催化反应器，选取三氯乙烯为污染物的工作系统进行气固相光催化反应研究．结果表明，在反应器内循环气流量大于３１０ｍＬ／ｍｉｎ时，消除了扩散的影响．当催化剂表面紫外光辐射强度小于０．５ｍＷ／ｃｍ~２和三氯乙烯浓度大于６７μｍｏｌ／Ｌ时．反应处于光子传递控制，光催化反应动力学方程为：ｒ_（ｏｖｅｒａｌｌ）＝１．０８ Ｉ_０．当催化剂表面紫外光辐射强度在０．５－２．０ｍＷ／ｃｍ~２和三氯乙烯初始浓度小于２５．００μｍｏｌ／Ｌ时，反应动力学完全符合Ｌａｎｇｍｕｉｒ－Ｈｉｎｓｈｅｌｗｏｏｄ动力学方程；在紫外光辐射强度大于５ｍＷ／ｃｍ~２和三氯乙烯浓度小于５．２０μｍｏｌ／Ｌ时，光催化反应速率与光强无关，与反应物浓度成正比．光催化反应处于表面作用控制．
A novel photocatalytic reactor with nitermittent recurrance was designed and the study on gas-solid phase photocatalytic reaction was carried out with trichloroethylene (TCE) selected as pollutant in the operating system. The mass transfer process was disappeared when the flow flux of recirculation gas was more than 310mL/min. When the ultraviolet light intensity on the catalyst surface I_o<0.5mW/cm^2 and the concentration of TCE(C_(TCE)>67μmol/L,the reaction was controlled by photon transfer step and the kinetics equation of photocatalytic reaction can be written as follows: r_(overall) =1.08 I_0. The kinetics of the reaction was corresponding with Langmuir-Hinshelwood kinetics equation under I_0>0.5 mW/cm^2 and <2.0mW/cm^2 and C_(TCE)<25.00 μmol/L. The reaction rate was independence of I_0 and formed direct ratio with C_(TCE) when I_0>5.0mW/cm^2 and C_(TCE)<5.20μmol/L; and the reaction was controlled by surface action step.
出处
《中国环境科学》
EI
CAS
CSSCI
CSCD
北大核心
2000年第4期301-304,共4页
China Environmental Science
基金
国家自然科学基金! (29636010)
上海市重大创新项目!(995211001)
关键词
三氯乙烯
二氧化钛
光降解
反应动力学
gas-solid phase
photocatalysis
trichloroethylene
kinetics model
titanium dioxide
