Biomimetic and Rubisco-Inspired CO2 Capture from Air

University Of Missouri-Columbia, Columbia MO

Investigators

Abstract

In this project, funded by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division, Professor Rainer Glaser of the Department of Chemistry at the University of Missouri, Columbia is developing carbon dioxide capture and release (CCR) systems for the reversible carbon dioxide capture from air. The design of this biomimetic CCR systems is informed by the understanding of the binding of carbon dioxide in the active site of the enzyme rubisco. A simple device for carbon dioxide enrichment in agricultural greenhouses is developed to demonstrate the CCR concept in a field test. Future use is envisioned for large-scale, distributed carbon dioxide removal from air and its subsequent permanent capture and storage. The project provides cross-disciplinary training (mechanistic, structural and computational chemistry; protein synthesis, and biomaterials). Additional broader impacts are achieved through the development of the "Chemistry is in the News" project in science communication and the scientific writing curriculum to instruct students about the scientific process, scientific writing, scientific peer review, and professional ethics. Detailed thermodynamic analyses performed for the carbon dioxide capture reaction with a small molecule model demonstrates the promise of rubisco-inspired, small peptide biomimetics as CCR systems with low energy requirements for carbon dioxide release. The realization of energy-efficient CCR systems requires the development of carbon dioxide capture reactions with negative reaction entropies of substantial magnitude. It is the goal of this research to identify small peptides with capture thermochemistry most suitable for effective capture and energy-efficient release. For this purpose, libraries of free and immobilized tetrapeptides are synthesized. Specific experiments include (a) silica particle synthesis and surface functionalization,(b) peptide immobilization on various supports,(c) characterization by spectroscopy and by peptide crystallography,(d) quantitative measurements of carbon dioxide sorption/desorption,and (e) the fabrication of a simple device for carbon dioxide enrichment. The experimental effort is accompanied by theoretical studies of the library of tetrapeptides to determine the thermochemistry and the kinetics of the carbon dioxide addition to the magnesium complexed tetrapeptides, to assess alternatives to magnesium.