摘要
采用改良的溶胶-凝胶法制备了Fe3+掺杂纳米TiO2(简写为Fe-TiO2)催化剂,并用X射线衍射、高分辨透射电子显微镜、傅里叶变换红外光谱、热重-差热分析等方法对其进行了表征。表征结果显示,Fe-TiO2催化剂的分散性好,平均粒径为9.37nm,比表面积为85.46m2/g;掺杂Fe3+不仅使TiO2的平均粒径减小,且有效抑制了TiO2的晶相转变,该催化剂保持单一的锐钛矿相结构。考察了Fe-TiO2催化剂光催化还原CO2的性能,实验结果表明,当Fe3+掺杂量为4.0%(相对于TiO2的质量分数)的Fe-TiO2催化剂用量1.0g/L、反应时间8h、CO2流量200mL/min、反应温度90℃、反应液中NaOH和Na2SO3的浓度均为0.10mol/L时,甲醇的产率高达308.76μmol/g(以每克催化剂上生成甲醇的物质的量计)。此外,对Fe-TiO2催化剂光催化还原CO2的机理进行了探讨。
Fe3＋ -doped nano-titania （ Fe-TiO2 ） catalyst of CO2 were prepared by an improved sol-gel method. for production of methanol by photoreduction The catalyst was characterized by means of XRD,HRTEM,FTIR and TG-DTG. Particle sizes of Fe-TiO2 were uniform and the average diameters was about 9.37 nm. The specific surface area of the catalyst was 85.46 m2/g in comparing with 58.13 m2/g of nano TiO2. Doping of Fe3＋ not only could increase specific surface area of Fe-TiO2, but also could effectively inhibit phase transformation from anatase phase to rutile, growth in size and aggregation of the particles even after calcination at 500℃. A photocatalytic reactor with a UV irradiator （λ = 254 nm） in the central part of the reactor for reduction of CO2 was designed and established. Under optimal reduction conditions： reduction temperature 90℃ reduction time 8 h, CO2 flow rate 200 mL/min, nano Fe-TiO2 catalyst 1.0 g/L, Fe3＋ doping amount 4.0% （based on mass of TiO2 ）, CNaOH 0. 10 mob/L, CNa2SO3 0.10 mob/L, yield of methanol reached 308.76 μmol/g （based on 1 g catalyst）, which was far more than that on nano TiO2 without doping of Fe3＋. Mechanism of CO2 photocatalytic reduction on Fe-TiO2 catalyst was proposed.
出处
《石油化工》
CAS
CSCD
北大核心
2009年第7期789-794,共6页
Petrochemical Technology
基金
国家自然科学基金项目(20876125)
陕西省教育厅科技计划资助项目(08JK451)
关键词
铁掺杂
纳米二氧化钛
光催化
二氧化碳还原
甲醇
iron doping
nano-titania
photocatalysis
carbon dioxide reduction
methanol
