کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
68327 48512 2006 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
SBA-15 supported HPW: Effective catalytic performance in the alkylation of phenol
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
SBA-15 supported HPW: Effective catalytic performance in the alkylation of phenol
چکیده انگلیسی

SBA-15 was synthesized using non-ionic surfactant as the structure directing agent at 40 °C. It was then impregnated with different loadings (10, 30, 50 and 70%) of phosphotungstic acid. They were characterized by XRD, N2 adsorption, FT-IR and DRIFT techniques. The physicochemical characterization revealed that SBA-15 could accommodate discrete phosphotungstic acid due to its large pore volume and high surface area. The catalytic activity of these materials was examined in the vapour phase tert-butylation of phenol using tert-butyl alcohol as the alkylating agent. The influence of reaction parameters such as reaction temperature, reactant feed ratio, WHSV and time on stream was studied, and the results were correlated with physicochemical characteristics of the catalysts. 4-tert-Butyl phenol was observed as the major product with high selectivity. Among the catalysts, 30% phosphotungstic acid supported SBA-15 showed high phenol conversion under optimum conditions, which is significantly higher than either phosphotungstic acid loaded mesoporous AlPO or AlMCM-41.

The present investigation reveals that Keggin structure of phosphotungstic acid is retained even at higher loadings in SBA-15. The 30%PW/SBA-15 material is found to possess high Bronsted acidity as evidenced from the pyridine adsorption studies. The catalytic activity of PW/SBA-15 samples in the tert-butylation of phenol illustrates that 30%PW/SBA-15 is the most active catalyst. Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Catalysis A: Chemical - Volume 260, Issues 1–2, 15 December 2006, Pages 49–55
نویسندگان
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