Asvin Sajeev Kumar | Technical University of Delft, Netherlands (original) (raw)
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Papers by Asvin Sajeev Kumar
Carbon dioxide (CO2) electrolysis on copper (Cu) catalysts has attracted interest for its direct ... more Carbon dioxide (CO2) electrolysis on copper (Cu) catalysts has attracted interest for its direct production of C2+ feedstocks. Using the knowledge that CO2 reduction on copper is primarily a tandem reaction of CO2 to CO and CO to C2+ products, we show that modulating CO concentrations within the liquid catalyst layer allows for C2+ selectivity of > 80 % at 200 mA cm‑2 over broad conversion conditions. The importance of CO pooling is demonstrated through residence time distribution curves, varying flow fields (serpentine/parallel/interdigitated), and flow rate. While serpentine flow fields require high conversions to limit CO selectivity and maximize C2+ selectivity, the longer CO residence times of parallel flow fields reach similar selectivity over broad flow rates. Critically, we show that parts of the catalyst area are predominantly reducing CO instead of CO2 as supported by CO reduction experiments, transport modelling, and achieving a CO2 utilization efficiency greater than ...
Journal of The Institution of Engineers (India): Series E, 2020
Permeable carbon atoms or aerogels support novel electrode materials. It is essential to improve ... more Permeable carbon atoms or aerogels support novel electrode materials. It is essential to improve the wetting surface area of carbon electrode for higher Capacitive Deionization (CDI) potency. To enhance the wettability of CDI electrodes, poly(vinyl alcohol) (PVA) binder (a water-soluble polymer) was used to fabricate the carbon electrodes, followed by the cross-linking of PVA with Glutaric Acid (GA). Morphological characteristics of modified electrodes were ascertained by Scanning Electron Microscopy. The primary purpose of this work is to investigate the desalting performance of PVA-bonded carbon electrodes by arranging a modified electrode with activated carbon powder and to observe its efficiency at a varied initial concentration of salt (400-1000 ppm). This makes CDI a feasible and economical means for the desalination of brackish water. The energy consumption during experiments was low, i.e., 2-5 kWh/m 3 of desalted wastewater.
The Journal of Physical Chemistry C
Steelmaking process is a highly carbon-intensive process. This is mainly due to the use of coke a... more Steelmaking process is a highly carbon-intensive process. This is mainly due to the use of coke as a reducing agent in the blast furnaces to produce carbon-rich pig iron, which in turn, is used for the production of low-carbon steel in the basic oxygen furnaces. The exhaust gases from the blast and basic oxygen furnaces, which mainly contain CO and CO2, are utilised for electricity generation, and thus, these pollutants are released to the atmosphere. One of the possible ways to treat these work’s arising gases (WAGs) is to convert them into syngas, which can then be further converted into syncrude via Fischer-Tropsch synthesis (FTS). The FTS syncrude can then be further refined and processed to produce liquid fuels such as gasoline, kerosene, diesel, etc. These synthetic fuels are sulphur-lean and are essentially capable of replacing the existing fossil-derived liquid fuels, thus contributing to curbing the carbon emissions. The main objective of this thesis was to develop a detail...
Carbon dioxide (CO2) electrolysis on copper (Cu) catalysts has attracted interest for its direct ... more Carbon dioxide (CO2) electrolysis on copper (Cu) catalysts has attracted interest for its direct production of C2+ feedstocks. Using the knowledge that CO2 reduction on copper is primarily a tandem reaction of CO2 to CO and CO to C2+ products, we show that modulating CO concentrations within the liquid catalyst layer allows for C2+ selectivity of > 80 % at 200 mA cm‑2 over broad conversion conditions. The importance of CO pooling is demonstrated through residence time distribution curves, varying flow fields (serpentine/parallel/interdigitated), and flow rate. While serpentine flow fields require high conversions to limit CO selectivity and maximize C2+ selectivity, the longer CO residence times of parallel flow fields reach similar selectivity over broad flow rates. Critically, we show that parts of the catalyst area are predominantly reducing CO instead of CO2 as supported by CO reduction experiments, transport modelling, and achieving a CO2 utilization efficiency greater than ...
Journal of The Institution of Engineers (India): Series E, 2020
Permeable carbon atoms or aerogels support novel electrode materials. It is essential to improve ... more Permeable carbon atoms or aerogels support novel electrode materials. It is essential to improve the wetting surface area of carbon electrode for higher Capacitive Deionization (CDI) potency. To enhance the wettability of CDI electrodes, poly(vinyl alcohol) (PVA) binder (a water-soluble polymer) was used to fabricate the carbon electrodes, followed by the cross-linking of PVA with Glutaric Acid (GA). Morphological characteristics of modified electrodes were ascertained by Scanning Electron Microscopy. The primary purpose of this work is to investigate the desalting performance of PVA-bonded carbon electrodes by arranging a modified electrode with activated carbon powder and to observe its efficiency at a varied initial concentration of salt (400-1000 ppm). This makes CDI a feasible and economical means for the desalination of brackish water. The energy consumption during experiments was low, i.e., 2-5 kWh/m 3 of desalted wastewater.
The Journal of Physical Chemistry C
Steelmaking process is a highly carbon-intensive process. This is mainly due to the use of coke a... more Steelmaking process is a highly carbon-intensive process. This is mainly due to the use of coke as a reducing agent in the blast furnaces to produce carbon-rich pig iron, which in turn, is used for the production of low-carbon steel in the basic oxygen furnaces. The exhaust gases from the blast and basic oxygen furnaces, which mainly contain CO and CO2, are utilised for electricity generation, and thus, these pollutants are released to the atmosphere. One of the possible ways to treat these work’s arising gases (WAGs) is to convert them into syngas, which can then be further converted into syncrude via Fischer-Tropsch synthesis (FTS). The FTS syncrude can then be further refined and processed to produce liquid fuels such as gasoline, kerosene, diesel, etc. These synthetic fuels are sulphur-lean and are essentially capable of replacing the existing fossil-derived liquid fuels, thus contributing to curbing the carbon emissions. The main objective of this thesis was to develop a detail...