SBIR Phase I: Novel Catalytic Membrane Reactor for the Production of Valuable Chemical Intermediates from Zero/Negative Value Feedstock and Waste

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project is to convert non-food cellulosic corn fiber, a low-value byproduct from corn ethanol plants, to fermentable sugars using a bolt-on catalytic membrane reactor without the need to construct new facilities. The successful completion of the project will enable corn ethanol producers to diversify revenue streams, maximize production efficiencies.

The proposed technology operates with higher efficiency than naturally occurring systems and can complete the conversion in less than one day, 5-10 times less than the exiting enzyme technology. The catalyst can be used repeatedly and is environmentally friendly.

The proposed project relies on a catalytic membrane reactor with a patented enzyme replacement catalyst to simultaneously convert cellulosic biomass into fermentable sugars and separate the hydrolyzed sugars with high yield in one step. This catalyst consists of two adjacent polymeric nanostructures, a polystyrene sulfonic acid and poly (ionic liquid) chains grafted from a membrane support.

Two types of grafted polymer chains will act cooperatively to bind and hydrolyze the biomass substrate, similar in nature to the functions of cellulase enzymes. The polystyrene sulfonic acid chain catalyzes the hydrolysis of the polysaccharides to soluble sugars whereas the poly (ionic liquid) chain enhances the catalytic activity and selectivity of the synthesized catalyst.

The catalytic activity and selectivity of the designed catalyst can be tuned and optimized by ring substitution and by varying independently the properties of the grafted nanostructures. A porous membrane with an appropriate pore size will enable the separation of monomer sugars immediately after they are released, thus driving the forward reaction, minimizing acid-catalyzed sugar degradation, and improving sugar yields.

In addition to fermentable sugars, the catalyst can be tuned to convert cellulosic biomass or other carbohydrates such as agricultural residues or food waste into platform chemicals for the production of bio-based products.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.