Diesel-like fuel production from catalytic cracking and esterification of waste oil

Abstract

The process of producing diesel-like fuel from combination of catalytic cracking with catalytic esterification was studied. The optimal technological conditions were obtained as follows: CaO as cracking catalyst, distillation temperature 320 – 350 °C, cracking temperature 480 – 500 °C, adding rate of waste oil feedstock 35 g/h, and sodium bisulfate as esterification catalyst with the amount 3 wt. % of pyrolytic product, and molar ratio 0.4 (methanol to pyrolytic product). Results of Fourier transform infrared spectroscopy (FTIR) indicated that the fraction distribution of product was modified by catalytic cracking process, and gas chromatography-mass spectrometry (GC-MS) analysis showed the esterification products consist of alkanes, alkenes, aldehyde, and fatty acid methyl ester of short chains below C16. And the acid value of pyrolytic product from the esterification process decreased remarkably from 40 mg KOH/g to 1.6 mg KOH/g. The properties of the final fuel product were measured as follows: density of 850 kg/m3, viscosity of 3.05 mm2/s, freezing point of −9 °C, and cold filter plugging point of −4 °C, indicating that the fraction distribution, properties, and applicability of the product from combination process were also further improved.