Title

Supported Palladium Catalysts for Liquid Phase Semi-Hydrogenation of Alkynes

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Chemistry

Date of Award

Fall 2018

Abstract

The semi-hydrogenation of alkynes to alkenes is an important transformation that is followed by both fine chemical and pharmaceutical industries, and thus the catalysts that specialize in such conversions are highly demanded. In this paper, the investigation focuses on the uses of supported palladium, palladium-copper, and palladium-ceria for liquid-phase semi-hydrogenation of ethyl phenylpropiolate. The semi-hydrogenation products are isolated and analyzed to determine the composition for the calculation of conversion and selectivity of reactions to measure the efficiency of catalysts under different reaction conditions. In order to achieve high selectivity and conversion rates, variables, such as reaction time, catalyst loading, and catalyst reduction procedure have been investigated. The addition of copper as second metal and ceria as the promoter for enhancing the selectivity of the catalyst has also been evaluated. The results prove that reduction temperatures did play an important role, reduction at 100 oC provided higher conversion with 0% selectivity and on the other hand, 300C provided higher conversion and selectivity. Catalysts prepared with nitrate as precursors proved to give better conversions over acetate as precursors, and a lower catalyst to substrate ratio provided better selectivities. The addition of a second metal (Cu) had a remarkable effect on the conversion and selectivity.

Advisor

Ben Jang

Subject Categories

Chemistry | Physical Sciences and Mathematics

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