Catalytic destruction of vinyl chloride over an alumina–supported platinum catalyst

Abstract

In this study, vinyl chloride (VC), the primary material for manufacturing polyvinyl chloride (PVC), is decomposed via catalytic oxidation (C-OX) using Pt/γ-Al₂O₃ catalyst. The effects of related major factors such as reaction temperature (T) and gas hourly space velocity on the conversion of VC (X) were examined. The values of T for achieving conversions of 50% and 90% are 504 and 580 K with C-OX, respectively, whereas those without Pt/γ-Al₂O₃ (i.e., thermal oxidation, T-OX) are 900 and 983 K, respectively, thus indicating that C-OX significantly reduces T for effective oxidation of VC to form CO₂, HCl, and Cl₂ when compared with T-OX. The mineralizations of carbon in VC to form CO₂ are 75.5% and 38% for C-OX and T-OX, respectively, at 90% X. The conversions of chlorine atom in 1,2-dichloroenane (DCEA) to Cl in HCl and Cl₂ are approximately 42% and 50.8% for C-OX and T-OX, respectively, at 90% X. These results indicate that the Pt/γ-Al₂O₃ catalyst exhibits remarkable performance for the mineralizations to form CO₂ even though a proportion of chlorine atoms are adsorbed on the Pt surface. The Eley–Rideal model can be used to describe the experimental results, thus yielding activation energy and frequency factor values of 49.0 kJ mol⁻¹ and 1.77 × 10⁶ s⁻¹, respectively. The obtained information and kinetic parameters are useful for the rational design and operation of C-OX process for the abatement of VC.

Keywords:

• Catalytic oxidation
• chloride volatile organic compound (CVOC)
• Pt catalyst
• vinyl chloride (VC)

Funding

The authors would like to thank the Ministry of Science and Technology (formerly, National Science Council) of Taiwan for the financial support of this research.