کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
54324 47005 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Magnesia-supported gold nanoparticles as efficient catalysts for oxidative esterification of aldehydes or alcohols with methanol to methyl esters
ترجمه فارسی عنوان
نانوذرات طلا از طریق مگنزیا به عنوان کاتالیزورهای کارآمد برای استریت اکسیداسیون آلدئید ها یا الکل ها با متانول به مشتقات استیل
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
چکیده انگلیسی


• Au/MgO is efficient for liquid base-free oxidative esterification of MAL to MMA.
• The basicity of support determines the catalytic behaviors.
• Activity depends on the size of Au and TOF increases with decreasing Au size.

Magnesia-supported gold nanoparticles were found to be highly efficient catalysts for the oxidative esterification of methacrolein (MAL) with methanol in the presence of molecular oxygen into methyl methacrylate (MMA) under liquid base-free conditions. MAL conversion of 98% and MMA selectivity of 99% were obtained over the Au/MgO catalyst at 343 K after a 2 h reaction. Besides the Au nanoparticles, the support also played pivotal roles in the oxidative esterification of MAL. The support with higher density of basic sites, particularly stronger basic sites, showed better performances for the formation of MMA. The enhancement of the intermediate formation by the basic sites is proposed to be the key reason for the superior activity of the Au/MgO catalyst. Our studies on the size effect of Au nanoparticles reveal that smaller Au nanoparticles favor the transformation of MAL, and the turnover frequency increases with decreasing mean size of Au nanoparticles. This suggests that the Au-catalyzed oxidative esterification of MAL is a structure-sensitive reaction. We have demonstrated that the Au/MgO catalyst is also applicable to the oxidative esterification of different aldehydes and alcohols.

Figure optionsDownload high-quality image (185 K)Download as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Catalysis Today - Volume 233, 15 September 2014, Pages 147–154
نویسندگان
, , , ,