Thermal extraction of bamboo with various solvents

Abstract

This thesis is to describe the potential of improvement by liquefaction with various solvents in pyrolysis in terms of conversion of bamboo to gas and liquid and quality of the bio-oils and residues produced. Fluidised sand bath and pressure gauge reactor were used for pyrolysis. The reactor was coupled with bamboo and a solvent and after 1 hour of pyrolysis and liquefaction at 410°C, the gas produced was collected in gas bag. To extract compounds uniformly from the chemically decomposed biomass mixture, soxhlet extraction was applied for between 17 and 20 hours. Then the residues were filtered. Solvents in the liquid were evaporated and distilled. Then, fractionation was performed and Gas Chromatography / Mass Spectrometry (GC-MS) was used to analyse the each fraction. Gas Chromatography (GC) and Elemental Analyser (EA) were used for analyses of the gas, bio-oil and residue. The analytical results showed the liquefaction increased the overall conversion rate of bamboo to liquid and gas (13 -33% more than pyrolysis without using any solvents) and improved quality of the residues ( decreased O(%), increased H(%), H/O: 0.5 – 0.8, O/C: 0.5 -0.12, HHV:24 - 32 MJ/kg, ash content: 5 – 10%, ash free content: 12– 35 %) and bio-oils ( decreased O(%), increased H(%), H/C: 1 -2, O/C: 0 – 0.05, HHV: 38 – 48 MJ/kg). Solvents in the liquefaction carried out as carriers of H or donors preventing from a cross-linking effect. The highest conversion rate (around 90%) was shown in tetralin due to its high hydrogen donating nature. The bio-oils are assumed as bitumen-like materials based on their dark brown colour, high viscosity and common functional groups with bitumen