Date of Award

Summer 8-18-2017

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science in Chemical Engineering (MSChE)

Department

Chemical Engineering

Advisor

Thomas J. Schwartz

Second Committee Member

M. Clayton Wheeler

Third Committee Member

William J. DeSisto

Abstract

The research here deals with the conversion of 5-hydroxymethylfurfural (HMF) into a tunable polymer. HMF is a known derivative that can be acquired from biomass via hydrolysis of cellulose followed by isomerization and finally selective dehydration. The process considered here is being developed to create tunable polymers from HMF and involves several different steps, three of which are covered here. The first step, an etherification, is the reaction of HMF with an alcohol. This step is significant because in this step the R-group from the alcohol is added to HMF and the branching portion formed is carried over to the final polymer giving the polymer unique properties. Thus, by changing the reacting alcohol in the first reaction the final polymer is changed. Upon evaluation of this step various catalysts were tested to see what active site was needed as well as how the structure of different catalysts with the previously determined site would affect the reactivity. In addition, R-group identity was evaluated to determine if the alcohol used effects the reactivity of the catalyst. For this reaction, it was found that a Brønsted acid active site was needed and that the pore structure of β-Zeolite (BEA) aided the production of an ether product giving both a high production rate and high selectivity for this product. Another important finding was that the identity of the R-group did not greatly affect the amount of ether product produced suggesting a role of the catalyst in the stabilization of HMF. The second step, not investigated here, is then to oxidize the ketone creating a carboxyl group in its place. The other two reactions investigated were the third and fourth reactions. These steps involve the hydrogenation of the furan ring followed by a ring rearrangement which causes the ring to grow to a six-membered lactone, still maintaining the ether branch from the first step. These two processes were first combined to determine if a bifunctional acid-metal catalyst could perform both steps under the same conditions. After it was determined that the conditions would need to be changed between reactions they were performed separately. For both reactions, it was found that an acid metal catalyst of palladium substituted β-Zeolite (Pd /BEA) was effective and from there separate reaction conditions were developed for each step. The final step, not examined here, is severing a key bond between the ketone and the oxygen within the expanded ring to create a monomer and then linking these monomers together to form the final polymer product. All three reactions evaluated here were performed individually to evaluate catalysts and reaction conditions. The products of each reaction were analyzed using GC-MS, GC-FID and HPLC.

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