Supercritical Hydrothermal Liquefaction of construction wood waste for the production of biocrude.

The trend of conversion of biomass to bio-fuels has received more attention due to efficient and sustainable biomass waste management systems. However, the implementation of biomass to bio-energy mainly depends on the biomass availability, efficient conversion technology and the cost competitiveness of biomass-based fuels as compared to producing fuels from conventional sources. Hydrothermal liquefaction (HTL) is a promising thermochemical process used to convert biomass into bio-crude. Due to abundant production, construction wood waste (CWW) can be considered as a resource-efficient candidate for using as a feedstock for HTL technology. Construction wood is generally preserved by chromated copper arsenate (CCA) to protect from the wood degradation. However, CCA metals are known to be released to the environment when CCA-impregnated wood is used for incineration process or dumped for the landfill, which results, the growth of environmental concerns about the contamination caused by CCA metals. This study aims to investigate the production of biocrude along with fate of heavy metals i.e. copper, nickle, zinc, and chromium, etc through HTL technology. Furthermore, to highlight the conversion efficiency of CWW into biocrude. In this study, the CWW was hydrothermally liquefied under supercritical compressed water at 400°C with alkali catalyst K2CO3. According to the nature of feedstock, the samples were categorized into 4 types i.e Untreated wood (UW), Non-hazardous (NHZ) treated wood, Hazardous (HZ) treated wood, and mixed (MX) wood. Apart from the biocrude production, the main challenge and novelty of this study is to investigate the distribution of heavy metals in HTL products.