Subcritical Aqueous Phase Reforming of Wastepaper for Biocrude and H2 Generation

This paper reports subcritical aqueous phase re-forming of wastepaper in presence of homogeneous Ni(NO3)(2) catalyst for biocrude and H-2 production. Reforming of aqueous wastepaper slurry (15 g/150 mL) was performed using 5 wt % catalyst in high-temperature high-pressure 300 mL SS316 PARR reactor at 200-275 degrees C. During the progress of the reforming reaction, gas and liquid samples were withdrawn at regular time intervals and analyzed using gas chromatography (GC), gas chromatography mass spectrometry (GC-MS), total organic carbon (TOC) analyzer, and high-performance liquid chromatography (HPLC). At 200 degrees C, negligible liquefaction of wastepaper was noticed; however, liquefaction was found to increase with temperatures from 225-275 degrees C. At 250 degrees C, about 44 wt % biocrude and 3.8 mol % H-2 were observed after 120 min of reaction time. The other gases observed in product gas were CO2, CO, and CH4 whereas the liquid phase (biocrude) was found to contain sugars (7.5 wt %), HMF/furfural (similar to 1 wt %), oxygenated hydrocarbons (42.4 wt %) and monocarboxylic acids (49.1 wt %) such as acetic, formic, propionic, and lactic (2-hydroxypropionic). The effect of Ni(NO3)(2) on the production of carboxylic acids as well as H-2 from the mixture of sugars (prepared as concentration ratio of the sugars observed during wastepaper reforming) was separately investigated with the viewpoint of developing understanding of possible reaction pathways.