Kinetic analysis and in-situ no support catalytic pyrolysis product distribution of Chinese herb residue

Abstract

Pyrolysis is a research hotspot for realizing Chinese Herb residue (CHR) treatment and resource utilization, but there is little reported about in-situ no support catalytic pyrolysis of CHR. In this work, kinetics and no support catalytic pyrolysis characteristics of CHR were studied using a thermogravimetric analyzer and a fix-bed reactor system, respectively. Three groups: Ni-Fe, Ni-Cu and Ni-Co add into CHR and three kinetic methods: Coats-Redfern (CR) method, Flynn-Wall-Ozawa (FWO) method and Distributed Activation Energy Model(DAEM)use for calculate the activation energy, then analyses the gas, bio-oil and char of CHR pyrolysis. The results show that, catalysts can reduce the pyrolysis reaction activation energy. In FWO and DAEM model, the reaction activation energy will increase sharply if the conversion over 0.7. Compare with no catalyst group, add catalyst can restrain gas generation but good for oil production and char formation. Meanwhile, the surface of char is smoother than no catalyst. After test the char, we find that, metals of Ni, Fe, Cu and Co almost enrich in char, which may reuse as catalytic. This study may provide a feasible direction for the industrial application of CHR.