Master of Science (MS), Ohio University, 2019, Chemical Engineering (Engineering and Technology)

The aim of this study is to first develop a non-precious metal oxide electrocatalyst for selective electrochemical oxidation of lignin. Next, the metal oxide electrocatalyst along with a modified metal electrocatalyst, previously developed in our research group are studied for the lignin electrolysis process in an anion exchange membrane (AEM) electrolysis cell. To that aim, four β-PbO2/MWNTs nanocomposites were developed via a wet-chemistry procedure and studied in a three electrode cell configuration. Product stream analysis was conducted by gas chromatography-mass spectroscopy (GS-MS). In addition, cyclic voltammetry (CV), linear sweep voltammetry (LSV) and potentiostatic measurements were carried out to evaluate electrocatalyst performance. The 33.3 wt% β-PbO2 nanocomposite possessed the highest electro-catalytic activity and stability for oxidation of lignin. Also, GC-MS results revealed that the β-PbO2/MWNTs nanocomposite is likely a selective electrocatalyst for conversion of lignin into low molecular weight aromatic (LMWA) compounds. The 33.3 wt% β-PbO2 nanocomposite and a modified bimetallic Ni-Co supported on TiO2 were used as the anodic catalyst in an AEM system to quantify H2 production and energy consumption rates of this system and compare them with recent efforts for water and lignin electrolysis in the literature. From the results, it was demonstrated that the β-PbO2/MWNTs nanocomposite is a stable and active electrocatalyst that can fasten the anodic lignin oxidation rate and therefore increase the cathodic reaction rate which is H2 evolution. At the end, our results showed that using β-PbO2/MWNTs as the anodic catalyst can lead to high hydrogen evolution rates (~45.6 mL/h) and increase energy efficiency by 20%, compared to a well-established and commercial alkaline water electrolyzer.

Committee: John A. Staser (Advisor); Kevin Crist (Committee Member); Marc Singer (Committee Member); Marcia Kieliszewski (Committee Member) Subjects: Chemical Engineering; Chemistry

Master of Science (MS), Ohio University, 2019, Chemical Engineering (Engineering and Technology)

The aim of this study is to first develop a non-precious metal oxide electrocatalyst for selective electrochemical oxidation of lignin. Next, the metal oxide electrocatalyst along with a modified metal electrocatalyst, previously developed in our research group are studied for the lignin electrolysis process in an anion exchange membrane (AEM) electrolysis cell. To that aim, four β-PbO2/MWNTs nanocomposites were developed via a wet-chemistry procedure and studied in a three electrode cell configuration. Product stream analysis was conducted by gas chromatography-mass spectroscopy (GS-MS). In addition, cyclic voltammetry (CV), linear sweep voltammetry (LSV) and potentiostatic measurements were carried out to evaluate electrocatalyst performance. The 33.3 wt% β-PbO2 nanocomposite possessed the highest electro-catalytic activity and stability for oxidation of lignin. Also, GC-MS results revealed that the β-PbO2/MWNTs nanocomposite is likely a selective electrocatalyst for conversion of lignin into low molecular weight aromatic (LMWA) compounds. The 33.3 wt% β-PbO2 nanocomposite and a modified bimetallic Ni-Co supported on TiO2 were used as the anodic catalyst in an AEM system to quantify H2 production and energy consumption rates of this system and compare them with recent efforts for water and lignin electrolysis in the literature. From the results, it was demonstrated that the β-PbO2/MWNTs nanocomposite is a stable and active electrocatalyst that can fasten the anodic lignin oxidation rate and therefore increase the cathodic reaction rate which is H2 evolution. At the end, our results showed that using β-PbO2/MWNTs as the anodic catalyst can lead to high hydrogen evolution rates (~45.6 mL/h) and increase energy efficiency by 20%, compared to a well-established and commercial alkaline water electrolyzer.

Committee: John A. Staser (Advisor); Kevin Crist (Committee Member); Marc Singer (Committee Member); Marcia Kieliszewski (Committee Member) Subjects: Chemical Engineering; Chemistry