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The kinetics of the liquid-phase hydrogenation of furfuraldehyde to furfuryl alcohol over a 5% Pt/C catalyst was studied in a slurry reactor. The solvent used was a mixture of 2-propanol and water (12.4% w/w). At the temperatures (403-448 K) and pressures (1.03-2.06 MPa) studied, all mass-transfer resistances (gas-liquid, liquid-solid, and intraparticle diffusion) were absent. The initial rate data were analyzed using a power-law model. The initial rates increased almost linearly with hydrogen concentration at all temperatures. The reaction showed a zeroth-order dependence with respect to furfuraldehyde above a feed concentration of 0.13 kmol m -3 . Below this value, the order was found to be 0.86. Therefore, a Langmuir-Hinshelwood-type model for a dual-site mechanism with molecular adsorption of all species was proposed, and this model provided the best fit of the experimental data. Catalyst reusability studies showed that the catalyst could be reused without any adverse effects.

Oxidation of lower molecular weight carboxylic acids such as formic, acetic, glyoxalic, and oxalic acids is often the rate-controlling step during wet oxidation (WO) of an aqueous waste stream exhibiting very high chemical oxygen demand (COD). The kinetics of WO of formic acid was studied in the absence and presence of a cupric sulfate as catalyst in the temperature range 150−240 °C and oxygen partial pressure range 0.345−1.380 MPa. Wet oxidation of acetic acid was carried out in the presence of cupric sulfate in the temperature range 215−235 °C. Homogeneous copper sulfate was found to be a very good catalyst for oxidation of formic acid and acetic acid.