Investigating solids present in the aqueous stream during STEX condensate upgrading—a case study

Abstract Steam explosion (STEX) of woody biomass is an efficient pretreatment method in the production water-resistant wood pellets. The STEX process also generates aqueous condensate stream containing dissolved organic compounds, with furfural as most abundant and valuable component. An industrial-scale recovery for other by-products therefore being developed built. One challenge has turned out to be formation solid particulate matter that can clog filters unit. We have analyzed both deposits fluids present at different points unit try identify origin particles using spectroscopic chromatographic analysis, elemental scanning electron microscopy. deriving from condensed steam contain small molecules, a separate low-density layer occurring some points. This largely consists extractives, typically terpenoids. In addition, heavy phase comprising mostly was found one sampling point. comprise black, insoluble material H/C ratio 0.88 O/C 0.26 very low ash content. IR spectra show content C–H functional groups, analysis supports interpretation are dominantly furfural-sourced humin-like polymers adsorbed or co-polymerized Particle been reproduced laboratory setting conditions similar those full-scale process.