Optimisation of slow-pyrolysis process conditions to maximise char yield and heavy metal adsorption of biochar produced from different feedstocks

Bioresour Technol. 2016 Aug:214:574-581. doi: 10.1016/j.biortech.2016.05.009. Epub 2016 May 7.

Abstract

The objective of this work was to identify biomass feedstocks and optimum pyrolysis process conditions to produce a biochar capable of adsorbing metals from polluted groundwater. Taguchi experimental design was used to determine the effects of slow-pyrolysis process conditions on char yield and zinc adsorption. Treatments were repeated using six candidate feedstocks (Lolium perenne, Lolium perenne fibre, Miscanthus x giganteus, Salix viminalis, Fraxinus excelsior and Picea sitchensis) and the resultant chars were tested for metal adsorption performance. Chars produced from L. perenne and its extracted fibre displayed the greatest zinc adsorption performance and removed 83.27-92.96% respectively. Optimum process conditions in terms of both char yield and zinc adsorption performance were achieved from slow-pyrolysis at 300°C for 2h using a feedstock with a particle size of less than 1mm.

Keywords: Bio-refinery; Grasses; Remediation; Taguchi-method; Zinc.

MeSH terms

  • Adsorption
  • Biomass
  • Bioreactors
  • Charcoal / chemistry*
  • Environmental Pollution
  • Environmental Restoration and Remediation / methods
  • Fraxinus / metabolism
  • Groundwater / chemistry
  • Hot Temperature
  • Lolium / metabolism
  • Metals, Heavy / chemistry*
  • Picea / metabolism
  • Salix / metabolism
  • Water Pollutants / chemistry
  • Zinc

Substances

  • Metals, Heavy
  • Water Pollutants
  • biochar
  • Charcoal
  • Zinc