New hydrocarbon biodiesel fuel and its production through catalytic decarboxylation of triglycerides with fixed bed reactor

Abstract

Production of new hydrocarbon biodiesel, which can be synthesized from various vegetable oils by catalytic decarboxylation, was investigated with a fixed bed rector. The diesel fraction oils of C10-C20 aliphatic hydrocarbons as the major products were obtained smoothly with the reactor using waste cooking oil, jatropha oil, dark oil, and palm oil. Higher yields of C21+ compounds, compared to the case of the agitating reactor, show that heavier products could flow out from the catalyst bed before decomposition to the lighter hydrocarbons. An MgO/SiO2catalyst was found to be more effective than an active carbon-supported catalyst. In particular, cracked oil with a lower acid value (AV) was obtained with the former catalyst. Influence of reaction temperature and the feed rate of the reactant was examined to find that optimal conditions are 450 °C and LHSV = 0.3 h-1. Although catalyst activity was maintained for about 24 h at LHSV = 0.3 h-1, deactivation by carbon deposition, especially for an increase in AV, was observed thereafter. However, the activity could be regenerated by a simple calcination with air.