Pyrolysis of Sedum plumbizincicola, a zinc and cadmium hyperaccumulator: pyrolysis kinetics, heavy metal behaviour and bio-oil production

摘要

Appropriate disposal of hyperaccumulator biomass is a problem inhibiting the widespread use of phytoremediation technology. In the present study, kinetic analysis of the pyrolysis process of Sedum plumbizincicola, the behaviour of heavy metals and bio-oil composition were studied. The kinetic analysis of the pyrolysis process shows that activation energy (E) changed from 150 to 186 kJ mol(-1) and the frequency factor (A) changed from 1.34 x 10(11) to 8.99 x 10(15) s(-1). At temperatures of 450-750 A degrees C more than 66.3 % of zinc (Zn) remained in the char. More than 87.6 % of the cadmium (Cd) was found in the bio-oil. Pyrolysis at 650 A degrees C led to the highest yield of alkanes with low-oxygen compounds found in the bio-oil. Pyrolysis at 650 A degrees C can likely offer a valuable processing method for S. plumbizincicola and recovery of Zn from the char and recovery of Cd from the bio-oil will be attempted in future research.