title: Enhancing biochar yield by co-pyrolysis of bio-oil with biomass: impacts of potassium hydroxide addition and air pretreatment prior to co-pyrolysis.
abstract: The influence of KOH addition and air pretreatment on co-pyrolysis (600 °C) of a mixture of bio-oil and biomass (aspen wood) was investigated with the goal of increasing biochar yield. The bio-oil was produced as a byproduct of the pyrolysis of biomass and recycled in subsequent runs. Co-pyrolysis of the biomass with the recycled bio-oil resulted in a 16% mass increase in produced biochar. The yields were further increased by either air pretreatment or KOH addition prior to co-pyrolysis. Air pretreatment at 220 °C for 3 h resulted in the highest mass increase (32%) compared to the base case of pyrolysis of biomass only. No synergistic benefit was observed by combining KOH addition with air pretreatment. In fact, KOH catalyzed reactions that increased the bed temperature resulting in carbon loss via formation of CO and CO2.
authors.affiliation: Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Dr. N.W., Calgary, AB T2N 1N4, Canada.
authors.forename: Andrei
authors.initials: A
authors.lastname: Veksha
authors.affiliation: Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Dr. N.W., Calgary, AB T2N 1N4, Canada.
authors.forename: Waheed
authors.initials: W
authors.lastname: Zaman
authors.affiliation: Canadian Energy Systems Analysis Research (CESAR) Initiative, Department of Biological Sciences, University of Calgary, 2500 University Dr. N.W., Calgary, AB T2N 1N4, Canada.
authors.forename: David B
authors.initials: DB
authors.lastname: Layzell
authors.affiliation: Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Dr. N.W., Calgary, AB T2N 1N4, Canada. Electronic address: jhill@ucalgary.ca.
authors.forename: Josephine M
authors.initials: JM
authors.lastname: Hill
mesh_terms: D000388:Air; D056804:Biofuels; D002606:Charcoal / Q000138:chemical synthesis* / Q000737:chemistry; D006358:Hot Temperature; D006878:Hydroxides / Q000737:chemistry*; D032107:Populus / Q000737:chemistry; D017680:Potassium Compounds / Q000737:chemistry*; D013696:Temperature; D013818:Thermogravimetry; D013997:Time Factors; D014934:Wood
chemical_list: D056804:Biofuels; D006878:Hydroxides; D017680:Potassium Compounds; C540010:biochar; D002606:Charcoal; C029943:potassium hydroxide
keywords: Air pretreatment; Bio-oil; Biochar; Potassium hydroxide; Pyrolysis