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Experimental And Modeling Of Co2 Removal From Gas Mixtures Using Membrane Contractors Packed With Glass Beads., Farah O.S. Abuhatab

Chemical and Petroleum Engineering Theses

Natural gas is one of the major natural resources in UAE which carries significant amounts of acid gases. For the purpose of utilizing or liquefying, the gas must be pre-treated by separating the major non-hydrocarbon gases, namely C0₂. Typical C0₂ separation processes involve separation using sorbents or solvent, cryogenic or membrane. Among these processes, the chemical absorption considered to be the most effective process to remove C0₂. However, this process carries several drawbacks such as flooding, foaming, entraining, channeling, and most importantly high capital and operating costs.

An integrated unit called gas absorption membrane (GAM) …

Absorption Of Carbon Dioxide Via Single And Blends Of Aqueous Amine Solutions And Nanofluids In Gasliquid Hollow Fiber Membrane Contactor, Zia Ur Rehman Said Rehman

Chemical and Petroleum Engineering Theses

In this work, CO₂ gas was absorbed from a gas mixture (20 vol.% CO₂ + 80 vol.% N₂) in a custom made Polyvinylidene fluoride (PVDF) hollow fiber membrane contactors by using a variety of single and blends of aqueous amine solutions and nanofluids. An ultrasonic dispersion method was used to prepare nanofluids where SiO₂ nanoparticles and carbon nanotubes (CNTs) were dispersed in deionized (DI) water without adding any surfactant. The prepared solvents were fed into the tube side of the membrane module, whereas the gas mixture was passed through the shell side. CO₂ absorption experiments were carried out using four …

Experimental And Modeling Of Co₂ Removal From Gas Mixtures Using Membrane Contactors Packed With Glass Beads, Farah O. S. Abuhatab

Chemical and Petroleum Engineering Theses

Natural gas is one of the major natural resources in UAE which carries significant amounts of acid gases. For the purpose of utilizing or liquefying, the gas must be pre-treated by separating the major non-hydrocarbon gases, namely CO₂. Typical CO₂ separation processes involve separation using sorbents or solvent, cryogenic or membrane. Among these processes, the chemical absorption considered to be the most effective process to remove CO₂. However, this process carries several drawbacks such as flooding, foaming, entraining, channeling, and most importantly high capital and operating costs.

An integrated unit called gas absorption membrane (GAM) consists of combining chemical absorption …

Nanoporous Carbon-Based Co2 Reduction Catalysts: Exploring The Combined Effects Of Surface Chemistry And Porosity, Wanlu Li

Dissertations, Theses, and Capstone Projects

For the first-time sulfur-doped, nitrogen-doped and sulfur, nitrogen-codoped nanoporous carbons were systematically studied as catalysts for CO₂ electrochemical reduction reaction (CO₂ERR). The Faradaic efficiencies (FE) of CO and CH₄ formation were calculated to evaluate the performance of these carbons. The best catalysts showed the FE of CO and CH₄ formation of 29% and 0.76%, respectively. It was found that the overall performance in CO₂ERR dramatically increased upon the reduction pretreatment of the carbons in N₂-saturated electrolyte before the CO₂ reduction process. The pretreated carbon showed the maximum FE of CO …

Variables Governing The Initial Stages Of The Synergisms Of Ultrasonic Treatment Of Biochar In Water Saturated With Carbon Dioxide, Adedapo Reuben Adeniyi

Electronic Theses and Dissertations

This work investigates the initial stage of the synergistic processes of acoustic treatment of biochar in water saturated with CO2 (AIChE Journal, 2014;60:1054-1065). Treatments with switchgrass and miscanthus biochars have been conducted to examine the effects of acoustic intensity, biochar/H2O ratio, CO2 concentrations of the solution, and that in the headspace above the solution. The changes in biochars’ heating values, carbon and hydrogen contents, internal surface area, and pore size distribution have significant technological implications and are the focal points of this study. The miscanthus and switchgrass biochars were produced via pyrolysis process at 700 oC and 550 oC, respectively. …

Ceria Nanostructured Catalysts For Conversion Of Methanol And Carbon Dioxide To Dimethyl Carbonate, Jawad Hassan A Al Drwish

Masters Theses

"In this study, three different shapes of ceria (CeO₂) nanostructures (e.g., nanooctahedra, nanocubes and nanorods) were synthesized via the hydrothermal method and screened for carbonylation reaction. Of these three shapes of nanostructures, the nanorod was doped with metals such as Ca, Ni, Cu, and Co by wet impregnation method. All materials were characterized by XRD, NH₃/CO₂-TPD, XRF, FTIR and N₂ physorption to determine the crystal size and phases, acid-base properties, metal loading, and surface properties. The obtained materials were employed as catalysts for the activation of Carbon Dioxide (CO₂) and methanol …