The application of a pulsed compression reactor for the generation of syngas from methane

Existing chemical reactors are approaching their technological limits. In order to make more significant progress in the energy efficiency of bulk chemical production processes, a radical shift in technology is needed.\ud The research was aimed at gaining some fundamental insight in the operation of the Pulsed Compression Reactor (PCR) in general, as well as the specific application for syngas generation from methane. The research can be divided into three parts: an investigation of heat transfer from the hot gas to the reactor walls and piston, an investigation of the chemistry of both partial oxidation of methane as well as steam reforming and the investigation of the stability of the PCR piston reciprocation. \ud To investigate the heat transfer from the hot gas to the reactor walls and piston two approaches were used. This was used to derive an empirical relation between the heat loss from the compressed gas in a single shot reactor and the compression pressure. This relation gives insight into the effect that the reactor walls and piston have on the chemistry occurring in the single shot reactor.\ud In the investigation of syngas generation from methane, the chemistry of both partial oxidation and steam reforming of methane were investigated in a single shot reactor. This was done both experimentally and by simulations of the process using models with detailed chemistry. \ud Lastly, an analysis of the experimental and numerical data obtained yielded a theory that describes the behavior of the PCR in continuous reciprocation with respect to reciprocation stability. It was shown that, if a point exists where the energy release of chemical reactions exactly compensates the energy losses, reciprocation will always converge to this point or cease. This is an important result with respect to the safety issues associated with the PCR operation

Parametrical Study on CO2 Capture from Ambient Air Using Hydrated K2CO3 Supported on an Activated Carbon Honeycomb

Potassium carbonate is a highly hygroscopic salt, and this aspect becomes important for CO2 capture from ambient air. Moreover, CO2 capture from ambient air requires adsorbents with a very low pressure drop. In the present work an activated carbon honeycomb monolith was coated with K2CO3, and it was treated with moist N2 to hydrate it. Its CO2 capture capacity was studied as a function of the temperature, the water content of the air, and the air flow rate, following a factorial design of experiments. It was found that the water vapor content in the air had the largest influence on the CO2 adsorption capacity. Moreover, the deliquescent character of K2CO3 led to the formation of an aqueous solution in the pores of the carrier, which regulated the temperature of the CO2 adsorption. The transition between the anhydrous and the hydrated forms of potassium carbonate was studied by means of FT-IR spectroscopy. It can be concluded that hydrated potassium carbonate is a promising and cheap alternative for CO2 capture from ambient air for the production of CO2-enriched air or for the synthesis of solar fuels, such as methanol

Parametrical Study on CO₂ Capture from Ambient Air Using Hydrated K₂CO₃ Supported on an Activated Carbon Honeycomb

Potassium carbonate is a highly hygroscopic salt, and this aspect becomes important for CO₂ capture from ambient air. Moreover, CO₂ capture from ambient air requires adsorbents with a very low pressure drop. In the present work an activated carbon honeycomb monolith was coated with K₂CO₃, and it was treated with moist N₂ to hydrate it. Its CO₂ capture capacity was studied as a function of the temperature, the water content of the air, and the air flow rate, following a factorial design of experiments. It was found that the water vapor content in the air had the largest influence on the CO₂ adsorption capacity. Moreover, the deliquescent character of K₂CO₃ led to the formation of an aqueous solution in the pores of the carrier, which regulated the temperature of the CO₂ adsorption. The transition between the anhydrous and the hydrated forms of potassium carbonate was studied by means of FT-IR spectroscopy. It can be concluded that hydrated potassium carbonate is a promising and cheap alternative for CO₂ capture from ambient air for the production of CO₂-enriched air or for the synthesis of solar fuels, such as methanol