Microwave-assisted fast co-pyrolysis behaviors and products between microalgae and polyvinyl chloride

Highlights: • Microwave-assisted co-pyrolysis of microalgae and polyvinyl chloride was studied. • Heating rate curves, yield of products, analyses of liquid and solid were investigated. • Bio-oil yields was enhanced while aromatics proportion was reduced at 1000 W. • Polyvinyl chloride can promote the production of aromatic hydrocarbons. Microwave-assisted fast co-pyrolysis of microalgae (MA) and polyvinyl chloride (PVC) was investigated. The pyrolysis profiles, yields of three-phase, the chemical composition of liquid and the ultimate analyses of solid residues were studied. When the power increased from 800 W to 1000 W, the bio-oil yields increased significantly while the proportion of aromatics and the heating value of oil and char decreased. A remarkable synergistic effect between MA and PVC was achieved in terms of oil yield when MA to PVC ratios were 5:5 and 3:7 at 800 W and 5:5 at 1000 W, respectively. With the increase of PVC, the content of nitrogenous and oxygenous organic matter in oil decreased from 29.65% to 0.38% at 800 W. The yield of solid decreased, the HHV increased and the values of H/C had a wave change. According to the quantity and quality of liquid and solid, 30% percentage of PVC was the suitable ratio.