Microwave Co-pyrolysis of mulberry branches and Chlorella vulgaris under carbon material additives

Abstract

In this paper, the pyrolysis properties, product yields and interactions of mulberry branches (MB) and Chlorella vulgaris (CV) at different blending ratios were studied by microwave oven. The effects of activated carbon (AC) and biochar (BC) on co-pyrolysis of MB and CV were studied at different amounts (5%, 10%, 15% and 20%). The results showed that the optimal blending ratio was 1:1 (C1M1), and its oil yield was the highest (31.05%). Compared with the PC group, the total weight loss and pyrolysis time of C1M1 group increased by 3.22% and decreased by 296 s, respectively. For bio-oil composition, compared with the theoretical value, the hydrocarbons in bio-oil of C1M1 group increased by 18.56%, while and nitrogenous compounds decreased by 11.54%. After, the optimum adding amount of AC and BC in the C1M1 group was 10% and 5%, respectively. Besides, compared with the non-additive group, the phenols content in bio-oil of the 10% AC and 5% BC groups increased by 10.21% and 3.52%, respectively, but the selectivity of hydrocarbons in bio-oil was reduced. In general, these two carbon material additives could significantly accelerate the co-pyrolysis process, but the content of hydrocarbons in bio-oil decreased and the content of nitrogen compounds increased.