Delignification of Rice Husk by Microwave Assisted Chemical Pretreatment

  • S. M. Laghari Civil Engineering Department, Universiti Teknologi Petronas, Malaysia
  • M. M. Tunio Department of Energy and Environment Engineering, Quaid-e-Awam University of Engineering, Science and Technology, Nawabshah, Pakistan
  • A. Q. Laghari Department of Chemical Engineering, Mehran University of Engineering & Technology, Pakistan
  • A. J. Laghari Dr. M. A. Kazi Institute of Chemistry, University of Sindh, Jamshoro, Pakistan
  • A. M. Ali Chemical Engineering Department, Mehran University of Engineering & Technology, Pakistan


Rice husk has the potential to be used as a source of alternative energy e.g. as biofuel. Its high lignin content, however, poses difficulty to this use. This study investigates the use of microwave assisted acidic and alkaline pretreatment methods to improve the characteristics of rice husk for energy production. The use of microwave assisted 3.5% NaOH provided optimum pretreatment of rice husk; the lignin content was reduced from 17.8 to 10.2%, the cellulose content increased from 38.6 to 59.3% and the C/N ratio was within the optimum range of 25-35. The results showed enhanced potential of biofuel production from rice husk by this pretreatment.

Keywords: chemical pretreatment, microwave, rice husk, lignocellulose biomass


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