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Abstract: The kinetics of gas-phase hydrodechlorination (HDC) of dichloromethane (DCM) with a Pd on activated carbon commercial catalyst has been studied in a fixed bed reactor within the 200–350°C temperature range. Different kinetic equations have been checked for describing the evolution of DCM. Statistical and physical reliable parameters were found for a Langmuir–Hinshelwood type expression with DCM adsorption as the controlling step. The reaction pathway and the kinetic model have been elucidated from the evolution of dichloromethane and the identified reaction products (methane, monochloromethane, ethane and ethylene). Adsorbed CH2Cl* radical, CH2 ** and C2H4 ** carbene species are proposed as the three intermediates evolving to the final reaction products. An apparent activation energy of 23.9±2.3kJmol−1 has been obtained for dichloromethane disappearance. [Copyright &y& Elsevier]

In this work, polymer-based spherical activated carbon (PBSAC) (dp = 500 μm) has been used as support to synthesize several Pd/PBSAC (1% wt.) catalysts. These catalysts have been tested in the hydrodechlorination (HDC) of 4‐chlorophenol (4-CP) in aqueous phase under ambient-like conditions (30 °C, 1 atm) at [4-CP] 0 = 3.9 mmol L −1 ; [catalyst] 0 = 1 g L −1 and 50 N mL H 2 min −1 . A sequential calcination (200 °C, air atmosphere) − reduction (80 °C, H 2 atmosphere) treatment was required to obtain active HDC catalysts with a convenient proportion of zero-valent and electrodefficient Pd species. This catalyst allowed to achieve complete conversion of 4-CP in 90 min reaction time, giving rise to phenol as main reaction product. An expanded kinetic model accounting for both consecutive reaction and sorption processes was used to successfully fit the experimental data. The values obtained for the effective rate constant of 4-CP disappearance (3.26–10.88 × 10 −4 s −1 ) and apparent activation energy (31.6 kJ mol −1 ) were close to the previously reported for powdered supported Pd catalysts. Remarkably, the catalyst showed a high stability in long-term continuous application (100 h on stream). [ABSTRACT FROM AUTHOR]