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نوع الوثيقة : مقال في مجلة دورية 
عنوان الوثيقة :
التحفيز الضوئى باستخدام الشمس لتعدين بديل النيتروفينول المطعم بأكسيد الزنك
Sunlight assisted photocatalytic mineralization of nitrophenol isomers over W6+ impregnated ZnO
 
الموضوع : علوم البيئة 
لغة الوثيقة : الانجليزية 
المستخلص : The synthesis, characterization and sunlight photocatalytic activity of W6+ impregnated ZnO for the degradation of nitrophenol isomers (2-nitrophenol, 3-nitrophenol, and 4-nitrophenol) is reported. Com-pared to pure ZnO, the impregnated catalysts exhibited a relatively improved spectral response in the visible region. The significant decrease in luminescence intensity for W6+ impregnated catalysts, relative to pure ZnO, established the effective trapping of charge carriers by surface bonded W6+ states. The char-acterization of the impregnated catalysts by FESEM, XRD and XPS revealed the presence of impregnated W6+ entities at the surface without affecting the morphology of ZnO. The synthesized catalysts exhibited superior activity for the mineralization of three nitrophenol isomers under sunlight exposure. Based on HPLC analysis, ∼99% of 2- and 4-nitrophenol was degraded in a short span of 120 min while a degrada-tion of >80% was observed in 3-nitrophenol in the same period. Time scale TOC measurements ratified the mineralization capability of impregnated catalysts. The release of NO2−, NO3− ions in the solution, pH measurements and non-existence of hydroxylated aromatic intermediates revealed that superoxide anion radicals (O2•−) are the major contributors in the degradation process. Besides the traces of coupling products, major intermediates identified by GC–MS analysis were either aliphatic dihydroxy alcohols, car-boxylic acids or other oxygen containing species depicting that the degradation process proceeds through ring opening mechanism. The W6+ impregnated catalyst also furnished high activity in the visible portion of sunlight. Suitable kinetic models were applied to estimate the rate constants (k) of various processes involved in the degradation process. The stability of the photocatalyst against photocorrosion and the possible decrease in the activity of the catalyst in the successive use was also monitored. 
ردمد : 0926-3373 
اسم الدورية : Applied Catalysis B: Environmental 
المجلد : 160 
العدد : 1 
سنة النشر : 1435 هـ
2014 م 
نوع المقالة : مقالة علمية 
تاريخ الاضافة على الموقع : Monday, August 4, 2014 

الباحثون

اسم الباحث (عربي)اسم الباحث (انجليزي)نوع الباحثالمرتبة العلميةالبريد الالكتروني
A. HameedHameed, A. باحث  
M. AslamAslam, M. باحث  
Iqbal M.I. IsmailIsmail, Iqbal M.I.باحث  
S. ChandrasekaranChandrasekaran, S. باحث magondal@kfupm.edu.sa
M.W. KadiKadi, M.W. باحث  
M.A. GondalGondal, M.A. باحث magondal@kfupm.edu.sa

الملفات

اسم الملفالنوعالوصف
 37281.pdf pdfSunlight assisted photocatalytic mineralization of nitrophenol isomers over W6+ impregnated ZnO

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