Removal of VOCs by Ozone: n-Alkane Oxidation under Mild Conditions

Alina I Mytareva,Igor S Mashkovsky,Alexander V Kazakov,Sergey A Kanaev,Dmitriy A Bokarev,Alexander Yu Stakheev,Galina N Baeva

doi:10.3390/catal11040506

Abstract

Volatile organic compounds (VOCs) have a negative effect on both humans and the environment; therefore, it is crucial to minimize their emission. The conventional solution is the catalytic oxidation of VOCs by air; however, in some cases this method requires relatively high temperatures. Thus, the oxidation of short-chain alkanes, which demonstrate the lowest reactivity among VOCs, starts at 250–350 °C. This research deals with the ozone catalytic oxidation (OZCO) of alkanes at temperatures as low as 25–200 °C using an alumina-supported manganese oxide catalyst. Our data demonstrate that oxidation can be significantly accelerated in the presence of a small amount of O3. In particular, it was found that n-C4H10 can be readily oxidized by an air/O3 mixture over the Mn/Al2O3 catalyst at temperatures as low as 25 °C. According to the characterization data (SEM-EDX, XRD, H2-TPR, and XPS) the superior catalytic performance of the Mn/Al2O3 catalyst in OZCO stems from a high concentration of Mn2O3 species and oxygen vacancies.

Highlights

Volatile organic compounds (VOCs) are a large group of chemical compounds with boiling points below 260 ◦C; they include alkanes, alkenes, aromatic hydrocarbons, aldehydes, ketones, alcohols, etc. [1]
The metal content is 9.4 wt% (Figure 1c), which is in a good agreement with data for inductively coupled plasma optical emission spectroscopy (ICP-OES)
The effect of O3 on the efficiency of alkane oxidation was studied in details. It was shown for the first time that it is possible to oxidize short-chain VOCs by air/O3 mixture at ambient temperatures

Summary

Introduction

Volatile organic compounds (VOCs) are a large group of chemical compounds with boiling points below 260 ◦C; they include alkanes, alkenes, aromatic hydrocarbons, aldehydes, ketones, alcohols, etc. [1]. Volatile organic compounds (VOCs) are a large group of chemical compounds with boiling points below 260 ◦C; they include alkanes, alkenes, aromatic hydrocarbons, aldehydes, ketones, alcohols, etc. VOCs are considered major air pollutants because of their significant contribution to the formation of photochemical smog, tropospheric O3 and secondary aerosols [2,3,4,5]. VOCs negatively affect human health because of their toxic, malodorous, mutagenic and carcinogenic nature [6]. The main anthropogenic sources of VOCs are vehicle exhaust fumes and emissions from chemical and power plants, petroleum refining, food and textile manufacturing, etc. Rapid urbanization and industrialization contribute to the growing emissions of VOCs into the environment. The development of effective methods and materials for the abatement of VOCs is of significant importance

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