Biocrude Production from Switchgrass Using Subcritical Water

Subcritical water is considered as an environmentally attractive solvent for organic matters and it can be used to convert biomass to liquid form (biocrude), which is a mixture of oxygenated hydrocarbons with a wide molecular weight distribution. The biocrude produced at the biomass production site can be pumped through pipelines to a centralized bio-refining facility for the production of variety of chemicals and renewable fuel.

Studies have been conducted on the liquefaction of switchgrass in sub-critical water in a flow through reactor. Effect of heterogeneous catalyst K2CO3, and temperature on the liquefaction of switchgrass is studied. The finely grounded switchgrass (40-60 mesh size) is packed in a tubular reactor, and preheated compressed water / K2CO3-water solution is passed through the packed bed at constant pressure. Reactor temperature is increased using electrical furnace. Studies have been conducted for the temperature range 230-260 °C. Liquid product is analyzed for total organic carbon (TOC) content and yields phenols, monomers, degradation products of glucose and organic acids.