Cascading use of macadamia nutshell for production of energy and adsorbents through biomass gasification

Abstract

This research delves into the viability of implementing macadamia nutshell in a cascading utilization strategy through gasification. The investigation entails a comprehensive scrutiny of the physiochemical attributes of the feedstock, coupled with an in-depth exploration of the transformations in the properties of both gaseous and solid products stemming from gasification under conditions pertinent to industry applications. Remarkably, macadamia nutshell gasification consistently produced syngas with high CO and H2 levels, resulting in an average Lower Heating Value of 13.8 MJ m-3. The characterization of the obtained chars unveiled a porous structure replete with micro-mesopores, attributing to a carbon dioxide adsorption capacity of 223 mg g-1. Surface analysis discerned a diverse array of functional groups and a marked presence of potassium and calcium (up to 31.37 wt% and 4.12 wt%, respectively). These findings bolster the potential of macadamia nutshell for cascading gasification, offering both energy generation and the production of solid adsorbents. The amassed dataset contributes to the realization of waste-free energy production through biomass gasification, thus propelling the progress of sustainable energy technologies.