This project investigates the fundamental and engineering aspects of CO₂ capture using aqueous ammonia–alkali carbonate/hydroxide solvent systems, with particular emphasis on mass transfer, chemical absorption, solvent speciation, and the influence of operating conditions on capture performance.
The investigated solvent systems comprise NH₃–KOH–K₂CO₃–KHCO₃–H₂O mixtures with systematically varied NH₃/KOH ratios, total salt concentrations, CO₂ loadings, and operating temperatures.
An engineering equilibrium framework is being developed to define the initial unloaded and loaded solvent compositions and to establish appropriate partitioning between the ammonia and carbonate absorption routes.
CO₂ absorption experiments are performed using a wetted wall column (WWC) to quantify gas–liquid mass transfer under controlled temperature, pressure, gas flow, and liquid-flow conditions.
The overall volumetric mass-transfer coefficient, absorption rate, and CO₂ absorption flux are evaluated to characterize the transport performance of the solvent.
Temperature-dependent experiments are used to distinguish the effects of temperature on equilibrium CO₂ capacity from its effects on reaction kinetics, diffusivity, viscosity, and overall mass transfer.
Main supervisor:
Nicolas von Solms
Co- supervisor:
Georgios Kontogeorgis
Philip Loldrup Fosbøl
Jyoti Shanker Pandey