UCLA

Methane is a gaseous chemical that can be converted into chemicals of interest useful to industry. However, the grand challenge in methane functionalization is the low reactivity of methane combined with the very high reactivity of its products. The high reactivity of its products leads to overoxidation, which in turn leads to low generation of products of interest since over oxidation leads to the formation of carbon dioxide. The goal of my research projects hereafter is to selectively oxidize methane into the chemical methyl hydrogen sulfate (MHS), which can be hydrolyzed into the commodity chemical of methanol. This is done by combining using transition metals catalysts coupled with electrochemistry in a two-chamber electrochemical system. Moreover, another aspect of my projects has been to propose electrochemical mechanisms for the electrochemical reactions. The first part of my dissertation focuses on using a vanadium molecular catalyst (chapter 2) to selectively oxidize methane electrocatalytically into MHS. Similarly, the second part of this dissertation focuses on the selective oxidation of methane into MHS by using a molecular silver catalyst (chapter 3). Both research projects of vanadium and silver molecular catalysts both use electrochemistry as the driving force at ambient conditions of room pressure and room temperature, however, the electrolyte used in the chemical reactions is not mild. The electrochemical reaction used 98% concentrated sulfuric acid. While room pressure and temperature is a big focus of the projects, there are studies in the research projects that utilize elevated pressures and temperatures. The use of elevated temperatures and pressures allows us to conduct experiments, which can give us an insight into the electrochemical mechanism that is occurring during the electrolysis reactions. To my knowledge, methane oxidation at room temperature and room pressure had not been seen before with a homogenous catalyst, so the innovation of my project is successfully proving that it is possible to oxidize methane at ambient conditions with a homogenous catalyst while proposing an electrochemical mechanism for the reactions.