Pyrolysis of Ligustrum vulgare waste and the effects of various operating parameters on bio-oil upgrading

In this work, the pyrolysis of biomass obtained from Ligustrum vulgare (LV) waste is examined with a focus on the yield and quality of the produced bio-oil. Effects of different operating parameters of the time and pyrolysis temperature, type and flow rate of carrier gas, and the use of different catalysts on the yield and composition of the produced bio-oil were studied. The TG analyses show that in pyrolysis temperature range of 200 to 600 degrees C about 75 wt% of the LV waste decreased and converted to liquid or gas products. The produced bio-oil was characterized by FTIR, GC, and GC-MS analyses. Total 55 compounds were identified in the produced bio-oils by GC-MS analysis. The main components of the produced bio-oils are acetic acid (16%), 2-propanon 1-hydroxy (16%), formic acid (15.5%), ethanol (6%), 1-propen-2-Ol (6%), and phenol (5.22%). The maximum yield of produced bio-oil is about 30 wt% which obtained in pyrolysis temperature of 500 degrees C, 120-min pyrolysis time, N-2 carrier gas with flow rate of 60 ml/min, and use of CaO as the catalyst.