Publication Date:
2017-05-20
Description:
n -Dodecyltriethoxysilane (DTEOS) modified NaHSO 4 /MCM-41 catalysts (silanized catalysts) were synthesized by different impregnation sequences and evaluated in the liquid-phase dehydration of castor oil. The samples were evaluated by X-ray diffraction, nitrogen adsorption-desorption, SEM, TEM, FT-IR spectroscopy, XPS, 29 Si MAS NMR spectroscopy, contact angle measurements, NH 3 -TPD, and pyridine-FT-IR spectroscopy. The analyses demonstrated that silanization enhanced the hydrophobicity of the catalysts, and the impregnation sequence of silanized catalysts had a significant effect on the NaHSO 4 dispersion, surface area, acid distribution, and hydrophobicity of the silanized catalysts. The catalytic activity of the silanized catalysts was much higher than that of NaHSO 4 /MCM-41. Among the silanized catalysts, the catalyst prepared by simultaneous impregnation with DTEOS and NaHSO 4 showed the highest iodine value of 141.8 [g(I 2 ) per 100 g] and lowest hydroxyl value of 11.3 [mg(KOH) · g –1 ].
Print ISSN:
0044-2313
Electronic ISSN:
1521-3749
Topics:
Chemistry and Pharmacology
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