Mohammed J Al-Marri | Qatar University (original) (raw)

Papers by Mohammed J Al-Marri

EngRN: Materials in Energy (Topic), 2019

This pilot plant study covered the CO2 absorption potential of a novel bi-solvent blend containin... more This pilot plant study covered the CO2 absorption potential of a novel bi-solvent blend containing AMP and 1,5–diamino–2–methylpentane (DA2MP). The CO2 concentration was kept at 15.1 vol.% to represent the flue gas from a coal-fired power plant. The simulated flue gas flow rate and the amine volumetric flow rate were 14 SLPM and 50 ml/min respectively. Comparative CO2 absorption analysis was conducted for the AMP-DA2MP blend and MEA (5 kmol/m3 or 30 wt.%). The concentration of AMP is 2 kmol/m3 while that of DA2MP was varied from 2 kmol/m3 to 3 kmol/m3 making the total concentration 4 kmol/m3 and 5 kmol/m3. The comparative analysis is based on rich amine loading, CO2 absorption rate, absorber overall mass transfer coefficient, and initial amine solution cost. The parametric effect of lean amine loading on the above-mentioned parameters was also investigated. Pilot plant results showed that the rich amine loading, CO2 absorption rate and absorber mass transfer coefficient of the AMP-D...

Energy Procedia, 2017

The major drawback of amine solvents for carbon dioxide (CO 2) capture application is their high ... more The major drawback of amine solvents for carbon dioxide (CO 2) capture application is their high regeneration energy (Qreg, kJ/g-CO 2). This experimental study analyzed the regeneration energy of single solvent MEA and tri-solvent blends containing AMP, MDEA and DETA at atmospheric pressure and 363 K. Their CO 2 absorption prior to their regeneration was conducted at 313 K, 101.3 kPa and 15.1 v/v% CO 2. The regeneration was done using two different methods (experimental and correlation) and the results showed the same trend. Results also indicated that the AMP-MDEA-DETA tri-solvent blends possessed lower regeneration energy than the standard 5 kmol/m 3 MEA. It was also discovered that higher absorption heats does not necessarily indicate higher regeneration energy, rather the effects of either sensible heat and/or heat of vaporization can greatly affect the regeneration energy.

International Journal of Greenhouse Gas Control, 2015

The equilibrium constant for the formation of carbamate in 3-amino-1-propanol-CO 2-H 2 O system w... more The equilibrium constant for the formation of carbamate in 3-amino-1-propanol-CO 2-H 2 O system was evaluated at different CO 2 loadings, different temperature values, and different amine protonation constant. The studied temperature varied from 298 to 328 K in an increment of 10 K and ionic strengths up to 1.5 M. The variation of the thermodynamic equilibrium constant with temperature was modeled according to the relationship of log K 1 = 1846.8/T − 4.4152, while temperature dependency of amine protonation constant was correlated by log K 2 = 2786.5/T + 0.5253.

Ecological Chemistry and Engineering S, 2012

Reduction of carbon dioxide emission from natural and industrial flue gases is paramount to help ... more Reduction of carbon dioxide emission from natural and industrial flue gases is paramount to help mitigate its effect on global warming. Efforts are continuously deployed worldwide to develop efficient technologies for CO 2 capture. The use of environment friendly amino acids as rate promoters in the present amine systems has attracted the attention of many researchers recently. In this work, the reaction kinetics of carbon dioxide with blends of N-methyldiethanolamine and L-Arginine was investigated using stopped flow technique. The experiments were performed over a temperature range of 293 to 313 K and solution concentration up to one molar of different amino acid/amine ratios. The overall reaction rate constant (k ov) was found to increase with increasing temperature and amine concentration as well as with increased proportion of L-Arginine concentration in the mixture. The experimental data were fitted to the zwitterion and termolecular mechanisms using a nonlinear regression technique with an average absolute deviation (AAD) of 7.6% and 8.0%, respectively. A comparative study of the promoting effect of L-Arginine with that of the effect of Glycine and DEA in MDEA blends showed that MDEA-Arginine blend exhibits faster reaction rate with CO 2 with respect to MDEA-DEA blend, while the case was converse when compared to the MDEA-Glycine blend.

Qatar Foundation Annual Research Conference Proceedings Volume 2014 Issue 1, 2014

Dispersed water droplets in organic liquids are commonl y encountered in the oil, chemical and bi... more Dispersed water droplets in organic liquids are commonl y encountered in the oil, chemical and biochemical industries. A t ypical example is the separation of dispersed water drops in cr ude oil, in order to prevent catal yst fouling, viscosit y and volume increase, and to meet qualit y specifications of the cr ude oil. Water drops can be removed from a continuous oil phase by various techniques, such as chemical demulsification, gravit y or centrifugal separation, pH adjustment, filtration, heat treatment, membrane separation and electrostatic-enhanced coalescence. Compared to other methods, electrical demulsification is considered to be superior in terms of energ y efficienc y. The electrostatic effects arise from the much higher values of dielectric permittivit y and conductivit y of water in comparison to oil. However, the mechanism of electrocoalescence is still not full y understood and most of the conventional electro-separators are rather bulky. There is, therefore, a compelling need to optimiz e the design and operation of these separators by means of a better fundamental understanding of the under l ying physics. This study aims at investigating the coalescence behaviour of water droplets in sunflower oil when the aqueous phase is present in the form of a chain of droplets. Chains easil y form in an emulsion, since droplets tend to align themsel ves with the direction of the electric field. A pair of ladder-wise electrodes was implemented to set up an electric field almost parallel to the flow direction of the droplets. This design ensures that adjacent droplets in a chain experience the maximum attractive force and does not significantl y disturb the hydrodynamics of the continuous phase. The effect of the electric field strength, frequenc y and waveform on the process performance has been investigated. Both constant and pulsed dc fields have been applied to the dispersion. S inusoidal, sawtooth and square waves have been employed as pulsed dc waveforms. Droplet siz e distributions at the outlet of the device were measured by image anal ysis. The outcomes of the research suggest that it is possible to find a combination of electrical field intensit y, frequenc y and waveform to maximiz e the separation efficienc y.

Carbohydrate Polymers, 2010

Abstract A procedure for synthesizing cellulose nanospheres with size of 5.9 and 10.9 nm for cott... more Abstract A procedure for synthesizing cellulose nanospheres with size of 5.9 and 10.9 nm for cotton linter and linen, respectively, was developed. A series of polyvinyl alcohol (PVA)/nano-cellulose films were cast. Mechanical, biodegradation and scanning electron micrograph (SEM) of nano-cellulose-filled PVA films were studied. With the addition of 20% nano-cellulose from linen there was an increase in the tensile strength and percentage elongation at break. The SEM indicates the change in the morphological structure of the PVA films in the presence of different percent of nano-cellulose.

Applied Thermal Engineering, 2016

Enhancing heat transfer in thermal fluid systems can contribute significantly towards the improve... more Enhancing heat transfer in thermal fluid systems can contribute significantly towards the improvement of thermal efficiency resulting in reducing energy consumption and hence carbon emission. Conventional fluids like water and oil have limited heat transfer potential. The need for the development of new classes of fluids with enhanced heat transfer properties is thus becoming essential. Many studies have developed nanofluids using nanoparticles, however, they showed a limited enhancement in heat transfer. This study investigated the heat capacity, enhancement of heat transfer, viscosity, and pressure drop of nanofluids with carbon nanotubes (CNTs) and CNTs doped with iron oxide nanoparticles (Fe 2 O 3-CNT). The surfaces of carbon nanotubes were doped with 1 wt.% and 10.0 wt. iron oxide nanoparticles. The pristine and doped CNTs were used to prepare heatexchange nanofluids with additive concentrations of 0.01, 0.05, and 0.10 wt.%. A shell and tube heat exchanger was used to evaluate the overall heat transfer coefficient and the associated pressure. The specific heat capacity of the nanofluids was measured by differential scanning calorimetry (DSC). The results showed that the specific heat capacity of the nanofluids with undoped and doped CNTs is significantly higher than that of pure water by about 10 % and 55%, respectively. The heat transfer rate of the nanofluids increased sharply with the CNT dosage the iron nanoparticles loading and reached up to 55% enhancement with doped CNTs. We observed that the power required to exchange 1.8 kW heat using nanofluid containing 0.1 wt.% of 10 wt. % Fe 2 O 3-CNTs was 20 times lower than the power required to exchange the same amount of heat using water. This is because the iron nanoparticles enhanced the dispersion of the CNTs and increased their heat capacity and thermal conductivity. Compared with that of pure water, the encountered pressure drop of the nanofluid at the same flow rate was almost unchanged, resulting in no extra pumping energy penalty.

Chemical Communications

Correction for ‘Distinct photodynamics of κ-N and κ-C pseudoisomeric iron(ii) complexes’ by Phili... more Correction for ‘Distinct photodynamics of κ-N and κ-C pseudoisomeric iron(ii) complexes’ by Philipp Dierks et al., Chem. Commun., 2021, 57, 6640–6643, https://doi.org/10.1039/D1CC01716K.

Journal of Materials Chemistry A, 2018

Photo-generated charge carrier dynamics in Ruddlesden–Popper 2D perovskites with linear (n-BA) an... more Photo-generated charge carrier dynamics in Ruddlesden–Popper 2D perovskites with linear (n-BA) and branched (iso-BA) butylamine as spacing cations have been studied by using transient absorption and time-resolved photoluminescence spectroscopies.

The Canadian Journal of Chemical Engineering, 2021

2017 IEEE 17th International Conference on Nanotechnology (IEEE-NANO), 2017

Development of a highly efficient, nickel-based nano-catalyst in the carbon dioxide reformation o... more Development of a highly efficient, nickel-based nano-catalyst in the carbon dioxide reformation of methane is reported. The alumina supported Ni-based catalyst with a metal loading of 5wt% was prepared via solution combustion synthesis (SCS) method and conventional wetness impregnation method. Compared to that of conventional Ni(I) catalyst, the Ni(SCS) catalyst exhibited high activity for methane conversion and superior selectivity for H2 and CO production during dry reforming of methane. This difference in the catalytical performances of both catalysts during the dry reformation of methane was attributed to difference in morphology and chemical structures of the catalysts. The HAADF-EDS analysis of the Ni(SCS)catalyst revealed Ni was homogeneously distributed over the substrate with an average particle size of 7±2.31nm. Additionally, SAED patterns suggested that nickel was mainly observed in the NiAl2O4 phase. These findings were affirmed by the XRD analysis. By contrast the Ni(I)...

Applied Surface Science, 2021

Abstract Shale gas is mostly made up of methane and is currently being exploited in fulfilling th... more Abstract Shale gas is mostly made up of methane and is currently being exploited in fulfilling the world’s energy demands. Density Functional Theory (DFT) and Molecular Dynamics (MD) techniques are employed for understanding methane transport in the pores at typical reservoir conditions. Shale, which is made up of clay and quartz-like material, is represented in this study by a combined silica-kaolinite surface. The simulations revealed that the interface is formed by a chemical bond between silicon to two oxygen atoms from the kaolinite surface. Physisorption is the mode of adsorption of methane irrespective of the position of the gas on the interface. However, methane has stronger adsorption on the kaolinite region than the silica region.

International Journal of Energy Research, 2021

In this study, we explore the effect of nickel incorporation in Cu/fumed-SiO 2 catalyst for CO 2 ... more In this study, we explore the effect of nickel incorporation in Cu/fumed-SiO 2 catalyst for CO 2 reduction reaction. Two catalysts, Cu and CuNi supported on fumed silica were synthesized using a novel surface restricted combustion synthesis technique, where the combustion reaction takes place on the surface of the inert fumed-SiO 2 support. An active solution consisting of a known amount of metal nitrate precursors and urea (fuel) was impregnated on fumed silica. The catalyst loading was limited to 1 wt% to ensure localized combustions on the surface of fumed-SiO 2 by restricting the combustion energy density. The synthesized catalysts were tested for CO 2 hydrogenation reaction using a tubular packed bed reactor between temperature 50 C and 650 C, where Cu/SiO 2 showed high CO 2 conversion to carbon monoxide, and the addition of Ni further improved the catalytic performance and showed some tendency for methane formation along with CO. Moreover, both the catalysts were highly stable under the reaction conditions and did not show any sign of deactivation for $42 hours time on stream (TOS). The catalysts were characterized using X-ray diffractometer (XRD), scanning electron microscope/energy dispersive X-ray spectrometer (SEM/EDX), transmission electron microscope (TEM), and the Brunauer-Emmet-Teller (BET) surface area measurement technique to understand their structural properties and to assess the effect of CO 2 conversion reaction. In situ DRIFTS was also used to investigate the reaction pathway followed on the surface of the catalysts.

International Journal of Greenhouse Gas Control, 2021

Abstract Carbon dioxide enhanced gas recovery (EGR) is a promising technique to sequester CO2 and... more Abstract Carbon dioxide enhanced gas recovery (EGR) is a promising technique to sequester CO2 and boost natural gas recovery from conventional depleted and unconventional tight gas reservoirs. Clay minerals are usually present in sandstone reservoirs and their influence on the efficiency of CO2-EGR is yet to be examined. In this study, the impact of clays on CO2 adsorption was evaluated for different sandstone rocks with various amounts and types of clays in the temperature range from 50–100 °C and pressures up 20 bars. The results showed that the adsorption of CO2 on sandstone rocks depends on the clay type, amount, and distribution. Clay-rich sandstone rocks, which have swellable clays such as illite, showed the highest CO2 uptake at a temperature of 50 °C and a pressure of 20 bars with total CO2 uptake of 4.6 and 2.6 mg/g for Kentucky and Scioto rocks, respectively. In contrast, sandstone samples with low clay content and a considerable percentage of carbonates showed CO2 uptake just above 1.5 mg/g for Bandera sandstone and 1.1 mg/ gm for Berea sandstone at similar conditions. Moreover, raising the temperature to 75 °C decreased the CO2 uptake on sandstones. However, the alteration of clays crystallinity at a temperature of 100 °C improves the CO2 adsorption. Adsorption isotherm analysis revealed that at the CO2 adsorption is monolayer at low temperature (50 °C) and pressure of 20 bars; whereas multilayer adsorption at 75 and 100 °C is predicted by Freundlich isotherm model. The thermodynamic analysis illustrated that the adsorption of CO2 on sandstone rocks is physisorption and exothermic on Kentucky, Scioto, and Berea sandstones and endothermic on Bandera sandstone. Core flooding experiments at 100 °C revealed the potential of CO2-EGR for clay-rich sandstone and highlighted the role of clays distribution.

Journal of Petroleum Science and Engineering, 2021

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Applied Surface Science, 2020

Abstract The adsorption of gas molecules (CO2, CH4, H2O, H2S and N2) on the “dense” (0 0 1) surfa... more Abstract The adsorption of gas molecules (CO2, CH4, H2O, H2S and N2) on the “dense” (0 0 1) surface of α-quartz has been investigated by means of Density Functional Theory (DFT) for the molecular characterization of Enhanced Gas Recovery (EGR) processes by CO2 injection. Several configurations have been studied for the different compounds. Overall, the five molecules are weakly physisorbed on the surface; no charge transfer takes place and no new bonds are formed. The potential surface is quite flat, with all the different values falling into a range of less than 0.15 eV. Consequently, all the molecules can easily move from a configuration to the other. As for the order of preference, hydrogen sulfide adsorbs the most with a maximum adsorption energy of −0.23 eV, followed by carbon dioxide with −0.21 eV. For the other three molecules (H2O, CH4 and N2), there is no net sequence but values lower than that of CO2 are inferred. Coverage analysis of CO2 and CH4 show that carbon dioxide can replace methane on the surface improving its extraction, but high CO2 concentration could weaken its adsorption, hindering the whole process. These results could prove to be useful in designing the EGR process based on CO2 injection.

Journal of Petroleum Science and Engineering, 2020