A hydrothermal co-liquefaction of spirulina platensis with rice husk, coconut shell and HDPE for biocrude production

Abstract

Hydrothermal liquefaction (HTL) is a thermochemical conversion process to produce biofuel from biomass. In this work, co-HTL of spirulina platensis (SP) with rice husk (RH), coconut shell (CS) and high-density polyethylene (HDPE) is performed, which are not reported in the literature. The maximum biocrude yield for SP and RH mixture is 20.1 wt% at blend ratio of 50:50, temperature of 300 °C, reaction time of 30 mins and solid loading of 20 wt% whereas for SP and CS mixture, the maximum biocrude yield of 12.2 wt% is obtained under same operating conditions. It is found that biocrude yield enhances with increasing blending ratio of SP to lignocellulosic biomass. For co-HTL of SP and HDPE, the maximum biocrude yield of 28.8 wt% is obtained at blend ratio of 50:50, 350 °C, 30 mins and 20 wt% solid concentrations. For this case, the biocrude yield decreases with increasing SP/HDPE ratios. Furthermore, various characterisation methods are used to analyse the quality of biocrude.