Experimental study on reactor scale-up for microwave-assisted pyrolysis of methyl ricinoleate

Abstract

The microwave-assisted pyrolysis reactor with microwave absorbent bed can work continuously and efficiently to pyrolysis reactions, which makes it potential for reactor scale-up. In this paper, the scale-up of microwave-assisted pyrolysis reactor using silicon carbide (SiC) as microwave absorbent bed that was used for methyl ricinoleate (MR) pyrolysis was studied. The microwave power, SiC bed diameter and MR feed rate were enlarged from 1 kW, 126 mm and 0.9 kg/h for the lab-scale reactor to 7 kW, 580 mm and 7.0 kg/h for our self-designed scale-up reactor, respectively. The results show that temperature distribution of the scaled up SiC bed surface before feeding of MR was uniform and stable, which provides favorable conditions for efficient pyrolysis reaction on the bed surface. The selectivity and yield of the target product undecenoic acid methyl ester were 75.55% and 63.08%, respectively that reached the lab-scale test results. It needs to be emphasized that the scale-up process of microwave-assisted pyrolysis of MR has no obvious scale-up effect by using the microwave intensification heating and the microdroplet rapid heating technology. This study will provide guidance for the large-scale application of the microwave-assisted pyrolysis reactor in chemical industry.