Research Projects

In our fossil fuel-dependent society, to fulfill the massive global energy demand of 1.62 EJ per day, about 25 million tons of coal, 97 million barrels of oil, and 11 billion m3 of natural gas are burnt every day releasing more than 40 billion tons (40 Gt) of anthropogenic CO2 into the environment annually. This has led to the CO2 concentration in the atmosphere surpassing 420 ppm, from the pre-industrial levels of about 280 ppm. If left unchecked, the levels of atmospheric CO2 concentration are projected to exceed 530 ppm by 2100! CO2 capture and storage (CCS), does not take the advantage of value-addition of the CO2-conversion process by producing chemicals and fuels from the captured CO2. Therefore, in order to provide renewable and sustainable carbon feedstocks on which we depend so much, the concept of “anthropogenic CO2 cycle” has been proposed based on CO2 capture and recycling to fuels and materials, as a supplement to the “natural photosynthesis-based CO2 cycle”. The major challenges include high cost and energy intensity of CO2-capture and CO2-conversion processes, which are conventionally operated separately in stand-alone manner in two different reactors with the help of two different materials (CO2-capturing sorbent and CO2-converting catalyst), and typically involve the following steps: CO2 capture, release (from the sorbent) compression, transportation and conversion. To address these challenges associated with the decoupled CO2-capture and CO2-conversion steps, an “integrated CO2 capture and conversion” (ICCCON) strategy, by coupling the CO2-capture and CO2-conversion in one step, bypassing the separate CO2-capture-desorption-compression steps, represents a promising and efficient alternative ‘single solution to dual problem’. The coupled ICCCON process can be executed over a capture-catalysis “dual-functional single material” (DFSM) (containing both the CO2-capturing sorbent (specifically a polyamine) and CO2-converting catalysts heterogenized onto a single hybrid material) in the same reactor, by feeding the CO2 stream directly into the reactor for consecutive capture and in-situ conversion process under heterogeneous reaction conditions, thus reducing the overall energy consumption. Advantageously, being a heterogeneous process, this approach also addresses the challenges related to the energy-intensive product separation steps typically involved in homogeneous catalysis. However, till date, there is no DFSM containing heterogenized/immobilized molecular complexes as the CO2-converting catalysts, reported yet for the production of CH3OH. One issue is that for CO2-to-CH3OH hydrogenation, well-defined molecular catalysts are just limited. Secondly, a proper integration of the CO2-capturing units and CO2-to-CH3OH converting molecular catalysts within a single support, to harness the power of cooperative activity from adjacent sites, is always a great synthetic challenge because the designed DFSMs should avoid considerable extent of material-leaching during reactions. Thus, the current project aims toward innovating a disruptive ICCCON approach using smartly engineered novel DFSM systems using polyamines as the CO2-capturing and molecular 1st row metal complexes MLn (M = Mn, Co, Fe and Cu; Ln = suitable polydentate ligand/s) as the CO2-converting catalyst system, both immobilized on a common solid support, for the production of CH3OH as the selective CO2-hydrogenated product in reusable heterogeneous catalysis manner. We seek to work with an industry partner to deploy the developed technology in a practical operational configuration. In this way, it would enable developing a sustainable alternative fuel economy by closing the ‘anthropogenic CO2 cycle’ through CO2-recycling. Notably, the current proposal is highly important to various energy and carbon neutrality-related initiatives of the Govt. of India, and the project, on successful completion/translation, may benefit the fuel/energy sectors of our nation.