The reforming of methanol is carried out in supercritical water at 276 bar and 700 °C to produce H 2 along with CO, CH 4 , and CO 2 . The reactions are catalyzed by the wall of the tubular reactor made of Inconel 600, which is an alloy of Ni, Cr, and Fe. Experiments are conducted to study the effects of the pressure, residence time, and steam-to-carbon ratio on the H 2 yield. The residence time is varied by changing the length of the reactor as well as the feed flow rate. Both the experimental results and equilibrium calculations show that, as the pressure is increased, methanation of CO and CO 2 takes place, resulting in a loss of H 2 . In addition, the methane formation is favored at a high residence time and low steam-to-carbon ratio. In this study, the following three strategies are proposed for the suppression of methane formation during the production of H 2 from methanol in supercritical water: (1) operation at a low residence time by having a small reactor length or a high feed flow rate; (2) addition of a small amount of K 2 CO 3 or KOH in the feed; (3) utilization of the surface catalytic activity of the reactor made of Ni-Cu alloy. All three of these strategies resulted in a significant reduction in the methane formation and corresponding enhancement in the H 2 production.

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Enzymatic and chemical oxidation of fiber surfaces has been reported in the literature as a method for producing medium density fiberboards without using synthetic adhesives. This work focuses on modifying the surface properties of wood fibers by the generation of free radicals using high-frequency ultrasound. A sonochemical reactor operating at 610 kHz is used to sonicate the aqueous suspensions of thermomechanical pulp fibers (TMP). TMP is analyzed using FTIR-transmission, FTIR-ATR spectroscopy and inverse gas chromatography (IGC). The non-conjugated carbonyl groups in TMP are represented by the peak area ratio A 1736 /A 1511 in the FTIR-transmission spectra and by A 1728 /A 1509 in the FTIR-ATR spectra. The increase in these ratios suggests that there is an increase in the number of non-conjugated carbonyl groups in TMP after sonication. To further investigate, sonication of the hydrolytic lignin was also carried out and analyzed using UV, UV-ionization and FTIR-transmission spectroscopy. The changes in the surface properties of the fibers are analyzed using IGC which showed an increase in the surface free energy of fibers. The effect of operating parameters such as power of ultrasound and sonication time is also studied.