Rapid and green synthesis of SAPO-11 for deoxygenation of stearic acid to produce bio-diesel fractions

A grinding synthesis approach is employed to prepare water containing gel. SAPO-11G was successfully prepared by a dry gel conversion method using water containing gel assisted by microwave radiation (120-180 degrees C, 2 h). Compared to hydrothermal system, approach employed in the present study show green characters such as conservation of energy and time, low cost of organic filler, and reducing wastewater discharge. Deoxygenation of stearic acid shows that Ni/SAPO-11 catalysts have a high selectivity to paraffin and a low yield to cracking products. Ni/SAPO-11G has a comparable activity (conversion> 95%) with Ni/SAPO-11H molecular sieves. Coke deposition in SAPO-11G is lower than that in SAPO-11H due to a lower concentration of extra-framework aluminum species (i.e., Lewis acid sites). These results propose a rapid way to prepare zeolites in an environmental friendly route and are important to produce bio-diesel fractions via a deoxygenation reaction.