Green diesel alkanes production by hydrodeoxygenation of neem seed oil over nickel-zeolite based catalyst

Abstract

Production of green diesel alkanes (DA) from vegetable oils is highly efficient in reducing dependence on finite fossil fuels. Catalytic hydrodeoxygenation (HDO) of non-edible extracted Neem seed oil (NSO) in a batch reactor over Ni/nano zeolite catalyst was investigated. The main issues of the effective HDO in terms of high yield and selectivity towards long-chain alkanes in mild operating conditions have been addressed. It was revealed that in the HDO reaction of NSO over 30% Ni/nano zeolite, the highest DAs (C10–C18) yields is 88.84% at 350 °C, process time of 4 h and hydrogen pressure of 8 bar. This performance can be attributed to the well-distributed Ni in the support surface as well as the acidity of the catalyst and proper textural properties. The results from current study demonstrated that the 30% Ni/nano zeolite catalyst is a potential HDO catalyst for the production of green diesel. In most experiments, the transformation of NSO into DAs was accomplished through decarboxylation (DCO2) and decarbonylation (DCO) routes. However, the progress of the process to the obtained products from the HDO pathway was surprisingly increased at temperatures above 300 °C.