Pr. Jun Cheng

To improve jet biofuel quality with increasediso-alkane content, a bi-functional catalyst with strong acidity was proposed to promote hydrodeoxygenation and hydrocracking of microalgae biodiesel through loading heteropoly acid H3PW12O40 (HPW) on Ni-based hierarchical mesoporous zeolite Y (meso-Y).It was found by quantum chemistry calculation that hydrodeoxygenation process of microalgae biodiesel was inclined to the decarboxylation pathway other than the decarbonylation pathway, because the total enthalpy of pentadecane and byproducts obtained through decarboxylation of methyl palmitate (C16:0) was lower by 187.7kJ/mol than that through decarbonylation.The selectivities of hydrocracking products with odd carbons (2n-1, n=5, 6, 7, 8) were higher than those with even carbons (2n), because the covalent bonds hydrocracked to removeeven carbons were 0.001%-0.149%longer in bond length and0.012%-1.697% lower in bond order than those hydrocracked to remove odd carbons.The experimental results of hydrodeoxygenation and hydrocracking conversion of microalgae biodiesel into jet biofuel carried out in a fixed bed reaction system agreed well with the quantum chemistry calculation results. The BET surface area of 10% Ni/meso-Y catalyst loaded with 4% HPW decreased by 14.3% to 453.9 m²/g, but its strong acid density increased by 30.6% to 1.62 mmol/g.Accordingly, the selectivity of jet biofuel in liquid productsconverted from microalgae biodiesel at 255ºC and 2 MPa hydrogen increased to 63.1%, in which iso-alkane selectivity markedly increased to 20.5% and arene selectivity was reasonable at 11.1%.

Dr. Jun Cheng is a Professor of State Key Laboratory of Clean Energy Utilization at Zhejiang University. He is engaged in the field of new energy, energy conservation and environmental protection, focusing on the efficient cleaning and transformation technologies such as the carbon dioxide fixation technology with microalgae to produce oil and biofuel, multi-generation system of biomass fermentation for hydrogen and methane etc.He has won the honors of National High Level Talents Special Support Plan, National Leading Talents for Scientific and Technical Innovation, New Century Excellent Talents in Universities of China and the 100th Excellent Doctor Degree Dissertation in China. He has presided 14 national and 8 provincial projects including 4 national natural science foundations, national 863 projects, 973 subjects, supporting plan project, national international cooperation projects etc. Furthermore, he is the project director of the National Key Research and Development Program "emission of carbon dioxide gas micro algae technology" and the chief expert of national 863 project "key technology of coal-fired flue gas CCUS". As the first or corresponding author, he has published more than 140 SCI papers and 40 authorized invention patents. He won the first prize of Zhejiang Natural Science in 2017, and won the second prize of National Science and Technology Progress twice in 2001 and 2009.