Hydroprocessing of waste cooking oil over a dispersed nano catalyst: Kinetics study and temperature effect

Haiping Zhang, Hongfei Lin, Weizhi Wang, Ying Zheng*, Peijun Hu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

56 Citations (Scopus)

Abstract

The kinetics of hydrodeoxygenation of waste cooking oil (WCO) is investigated with unsupported CoMoS catalysts. A kinetic model is established and a comprehensive analysis of each reaction pathway is carried out. The results show that hydrodecarbonylation/decarboxylation (HDC) routes are the predominant reaction pathways in the elimination of oxygen, with the rate constant three times as high as that of hydrodeoxygenation (HDO). However, the HDC activity of the CoMoS catalyst deactivates due to gradual loss of sulfur from the catalyst. HDO process is insensitive to the sulfur deficiency. The kinetic modeling shows that direct hydrodecarbonylation of fatty acids dominates the HDC routes and, in the HDO route, fatty acids are transferred to aldehydes/alcohols and then to C-18 hydrocarbons, a final product, and the reduction of acids is the rate limiting step. The HDO route via alcohols is dominant over aldehydes due to a significantly higher reaction rate constant. The difference of C-18/C-17 ratio in unsupported and supported catalysts show that a support with Lewis acid sites may play an important role in the selectivity for the hydrodeoxygenation pathways and promoting the final product quality

Original languageEnglish
Pages (from-to)238-248
Number of pages11
JournalApplied Catalysis B: Environmental
Volume150-151
Early online date14 Dec 2013
DOIs
Publication statusPublished - 05 May 2014

Keywords

  • Unsupported catalyst
  • CoMoS
  • Waste cooking oil
  • Hydroprocessing
  • Kinetics
  • SULFIDED NIMO/GAMMA-AL2O3
  • DIESEL
  • HYDRODEOXYGENATION
  • DEOXYGENATION
  • REFINERIES
  • MIXTURES
  • BIOFUEL
  • ESTERS
  • ACID
  • FUEL

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