Microwave catalytic co-pyrolysis of Chlorella vulgaris and rice straw over Cu/X (X = activated carbon, HZSM-5): Characteristics and bio-oil analysis

The weight loss characteristics, production distribution, and quality of bio-oil could be improved through catalytic co-pyrolysis of rice straw (RS) and Chlorella vulgaris (CV) under modified catalysts. Therefore, modified catalysts Cu/AC (activated carbon) and Cu/HZSM-5 were proposed. In this study, the effects of Cu/AC and Cu/HZSM-5 as modified catalysts on the microwave catalytic co-pyrolysis (CV:RS = 7:3) at different Cu loadings (1 wt%, 4 wt%, 7 wt%) and additive amounts (5 %, 10 %, 20 %, 30 %) were investigated. The results revealed that Cu/AC and Cu/HZSM-5 positively influenced bio-oil production and selectivity of hydrocarbons, but also prolonged the reaction time. At 10 % addition, 1 wt% Cu/AC exhibited the highest average weight loss rate (R_a) and the highest production of bio-oil (31.13 %). For Cu/HZSM-5, the highest production of bio-oil (28.37 %) was obtained with 7 wt% Cu/HZSM-5. Remarkably, the hydrocarbon content (57.22 %) in the bio-oil obtained from 4 wt% Cu/HZSM-5 was the highest among all groups.