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Ahmed A Abdala | Texas A&M University - Academia.edu

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Ahmed A Abdala

Texas A&M University, Chemical Engineering, Faculty Member

The Petroleum Institute, Chemical Engineering, Faculty Member

Hamad Bin Khalifa University, College of Science and Engineeirng, Faculty Member

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University of Tehran

University of Virginia

Bhabha Atomic Research Centre

Virginie Boucher

CSIC (Consejo Superior de Investigaciones Científicas-Spanish National Research Council)

VIT University

Prof.Dr. İbrahim USLU

Gazi University

Kenneth Vecchio

University of California, San Diego

DR.GIRISH JOSHI

VIT University

Nawa Raj Khatiwada

Kathmandu University

University of California, Riverside

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Papers by Ahmed A Abdala

Effect of Thermally Reduced Graphene on the Characteristics and Performance of Polysulfone Mixed Matrix Ultrafiltration Membranes

Membranes, Aug 20, 2023

Ultrafiltration (UF) polymeric membranes are widely used in water treatment and support desalinat... more Ultrafiltration (UF) polymeric membranes are widely used in water treatment and support desalination and gas separation membranes. In this article, we enhance the performance of Polysulfone (PSF) mixed matrix membranes (MMMs) by dispersing different concentrations of thermally reduced graphene (TRG) nanofillers. The UF PSF-TRG MMMs were fabricated via the phase inversion process, and the impact of TRG loading on the characteristics of the membrane, including hydrophilicity, porosity, roughness, and morphology, were analyzed using a contact angle measurement, atomic force microscopy (AFM), scanning electron microscopy (SEM), and dynamic mechanical analysis. Incorporating TRG into the PSF matrix led to favorable effects in the instantaneous de-mixing during phase inversion, increasing the porosity and hydrophilicity of MMMs and improving the mechanical properties of the membranes. Moreover, membrane performance was examined to remove dispersed oil from oil-water emulsion and support air-dehumidification membranes. MMM performance in terms of flux and oil rejection was superior to the control PSF membrane. Incorporating 0.25% TRG into PSF resulted in a 70% water flux increase and higher oil rejection compared to the control PSF membrane. As a support for air-dehumidification membranes, the MMM also demonstrated enhanced humidity reduction and an over 20% increase in water vapor permeance over the control PSF membrane. These results indicate that the PSF-TRG MMMs are an excellent candidate for reliable oil-water separation and as a support for air-dehumidification membranes.

A new series-parallel hybrid electric vehicle configuration based on an induction motor coupled to a DC machine

Scientific Research and Essays, Dec 31, 2010

With emphasis on a cleaner environment and efficient operation, vehicles today rely more and more... more With emphasis on a cleaner environment and efficient operation, vehicles today rely more and more heavily on electrical power generation for success. In this paper, to improve the speed performance of the drive against uncertainties caused by load disturbances, an integral switching surface couple mode speed controller was proposed. As such, mathematical modeling of the HEV components as the three phase induction motor coupled to the DC motor in hybrid electric vehicle was introduced. The controller of the 'induction motor' (IM) was designed based on input-output feedback linearization technique. It allowed greater electrical generation capacity and the fuel economy and emissions benefits of hybrid electric automotive propulsion. Hybrids transient torque allows the use of start/stop operation as well as brake energy regeneration. Thus, the results of Matlab-Simulink simulations and a comparison between the control schemes are presented.

Mesoporous PbO nanoparticle-catalyzed synthesis of arylbenzodioxy xanthenedione scaffolds under solvent-free conditions in a ball mill

RSC Advances, 2019

An efficient one-pot multicomponent protocol was developed for the synthesis of arylbenzodioxy xa... more

Rheology control by modulating hydrophobic and inclusive associations of side-groups in poly (acrylic acid)

Asia-Pacific Journal of Chemical Engineering, 2009

ABSTRACT

Facile In Situ Fabrication of Nanostructured Graphene–CuO Hybrid with Hydrogen Sulfide Removal Capacity

Nano-Micro Letters, 2016

A simple and scalable synthetic approach for one-step synthesis of graphene-CuO (TRGC) nanocompos... more A simple and scalable synthetic approach for one-step synthesis of graphene-CuO (TRGC) nanocomposite by an in situ thermo-annealing method has been developed. Using graphene oxide (GO) and copper hydroxide as a precursors reagent, the reduction of GO and the uniform deposition of in situ formed CuO nanoparticles on graphene was simultaneously achieved. The method employed no solvents, toxic-reducing agents, or organic modifiers. The resulting nanostructured hybrid exhibited improved H 2 S sorption capacity of 1.5 mmol H 2 S/g-sorbent (3 g S/100 g-sorbent). Due to its highly dispersed sub-20 nm CuO nanoparticles and large specific surface area, TRGC nanocomposite exhibits tremendous potential for energy and environment applications.

In situ formed graphene/ZnO nanostructured composites for low temperature hydrogen sulfide removal from natural gas

RSC Advances, 2016

Nanostructured composites of graphene and highly dispersed sub-20 nm sized ZnO nanoparticles (TRG... more

Polymer membranes for acid gas removal from natural gas

Separation and Purification Technology, 2016

The use of polymeric membrane technology is an exciting approach towards the removal of acid gase... more The use of polymeric membrane technology is an exciting approach towards the removal of acid gases, namely, carbon dioxide and hydrogen sulfide, from natural gas streams. Polymer membranes exhibit good mechanical, thermal and chemical stabilities. These membrane materials can also possess desirable transport properties such as high permeability and selectivity. A number of studies have attempted to improve these properties without compromising the advantages of existing technologies. Various preparations and structures of polymer membranes were reviewed. The structure-property analyses of these polymer membranes used for acid gas removal followed by their selectivity-permeability relationship and economic aspects are considered here.

Recent advances in graphene based gas sensors

Sensors and Actuators B: Chemical, 2015

ABSTRACT

Compositions Including Poly (Hydroxyalkanoates) and Graphene

Polymerization Method for Formation of Thermally Exfoliated Graphite Oxide Containing Polymer

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIW US007659350B2 (12) United States Patent ao) Pa... more IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIW US007659350B2 (12) United States Patent ao) Patent no.: us 7,659,350 B2 Prud'Homme et al. (45) Date of Patent: Feb. 9,2010 (54) POLYMERIZATION METHOD FOR FORMATION OF THERMALLY EXFOLIATED GRAPHITE OXIDE CONTAINING POLYMER (75) Inventors: Robert K. Prud'Homme, Lawrenceville, NJ (US); Ilium A. Aksay, Princeton, NJ (US); Douglas Adamson, Skillman, NJ (US) (73) Assignee: The Trustees of Princeton University, Princeton, NJ (US) ( * ) Notice: Subject to any disclaimer, the term of this patent ...

Thermally Conductive Polyethylene/Expanded Graphite Composites as Heat Transfer Surface: Mechanical, Thermo-Physical and Surface Behavior

Polymers, 2020

Composites of high-density polyethylene (HDPE) and expanded graphite (EG) are prepared for heat e... more Composites of high-density polyethylene (HDPE) and expanded graphite (EG) are prepared for heat exchangers in multi-effect distillation (MED) desalination. At 50 wt.% EG loading, the thermal conductivity of HDPE was increased by 372%. Moreover, the surface wettability of the HDPE/EG composite was enhanced by corona and RF plasma treatment as demonstrated by the increase in surface free energy from 28.5 mJ/m2 for untreated HDPE/EG to 55.5 and 54.5 mJ/m2 for HDPE/EG treated by corona and RF plasma, respectively. This enhanced surface wettability was retained over a long time with only a 9% and 18% decrease in RF and corona plasma-treated samples’ surface energy after two months. The viscoelastic moduli and the complex viscosity profiles indicated that EG content dictates the optimum processing technique. At loading below 30 wt.%, the extrusion process is preferred, while above 30 wt.% loading, injection molding is preferred. The plasma treatment also improved the HDPE/EG composite ove...

Developing Hydrophobic Graphene Foam for Oil Spill Cleanup

Industrial & Engineering Chemistry Research, 2017

Oil spills have been responsible for a number of environmental problems such as water pollution, ... more Oil spills have been responsible for a number of environmental problems such as water pollution, subsequent danger to aquatic life along with massive oil losses. Such disasters have stimulated the need for development of novel materials with improved sorption capacity for oil-spill cleanup. Among various available methods, the use of adsorbents holds great promises to remove and recover oil from minor or major spills. In the present work, we report the development of hydrothermally-reduced graphene oxide foam (RGO) functionalized with, Fe 3 O 4 , magnetic nanoparticles (MNP) for sorption of oil. Magnetic nanoparticles were used to produce RGO-MNP hybrid foams which could be separated by a magnetic field. The synthesized RGO and RGO-MNP hybrid foams were characterized by using Fourier Transform Infrared spectroscopy (FTIR), Raman spectroscopy, X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA). Motor oil was used as the adsorbate to determine the sorption capacity of the produced foams. Experimental results revealed that graphene foam is an excellent candidate to be used as a sorbent for oil spill cleanup due to its high specific surface area and hydrophobicity.

Adsorptive Removal of Azithromycin Antibiotic from Aqueous Solution by Azolla Filiculoides-Based Activated Porous Carbon

Nanomaterials, 2021

Due to the shortage of freshwater availability, reclaimed water has become an important source of... more Due to the shortage of freshwater availability, reclaimed water has become an important source of irrigation water. Nevertheless, emergent contaminants such as antibiotics in reclaimed water can cause potential health risks because antibiotics are nonbiodegradable. In this paper, we report the adsorptive removal of azithromycin (AZM) antibiotics using activated porous carbon prepared from Azolla filiculoides (AF) (AFAC). The influence of the adsorption process variables, such as temperature, pH, time, and adsorbent dosage, is investigated and described. The prepared AFAC is very effective in removing AZM with 87% and 98% removal after the treatment of 75 min, at 303 and 333 K, respectively. The Langmuir, Temkin, Freundlich, and Dubinin–Radushkevich isotherm models were used to analyze the adsorption results. The Freundlich isotherm was best to describe the adsorption isotherm. The adsorption process follows second-order pseudo kinetics. The adsorption was endothermic (ΔH°= 32.25 kJ/...

Thermally enhanced pristine polyolefins: fundamentals, progress and prospective

Journal of Materials Research and Technology, 2020

The low thermal conductivity of polymers hinders their use in applications requiring high thermal... more The low thermal conductivity of polymers hinders their use in applications requiring high thermal conductivity such as electronic packaging, heat exchangers, and thermal management devices. Polyethylene and polypropylene (polyolefins) account for ∼55% of the global thermoplastic production. Improving the thermal conductivity of this class of thermoplastics is important for many applications. This comprehensive review analyzes the advances on enhancing the thermal conductivity of pristine polyolefins. First, the mechanism of thermal transport in polymers and the key parameters that govern conductive heat transfer through polymers are discussed. Moreover, the progress in modeling and simulation of thermal conductivity of polyolefins are analyzed. Furthermore, the different approaches to enhance the thermal conductivity of polyolefins through controlling their microstructure, crystallinity and chain orientation are presented. Finally, the key challenges and prospective directions for developing thermally enhanced pristine polyolefins are outlined.

Data on characterization and performance of aspartic acid functionalized graphene oxide-polysulfone mixed matrix membranes

Data in Brief, 2020

Structure and microstructure characterization are very important for determining the membrane hyd... more Structure and microstructure characterization are very important for determining the membrane hydrophilicity, morphology, porosity, and mechanical properties that affect the membrane separation performance and durability. This article analyzes the morphological differences between graphene oxide (GO) and functionalized graphene oxide (f-GO) based on data from SEM imaging. nalysis of the morphology of mixed matrix membrane (MMMs) through SEM, mechanical properties through DMA and hydrophilicity through contact angle data. This dataset will support the original research article "Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-water emulsion separation" (Abdalla, Wahab and Abdala, 2020; doi.

Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-water emulsion separation

Journal of Environmental Chemical Engineering, 2020

Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-wa... more Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-water emulsion separation Omnya Abdalla (Investigation) (Formal analysis) (Visualization) (Writing-original draft), Md A. Wahab (Validation) (Writing-review and editing) (Formal analysis), Ahmed Abdala (Funding acquisition) (Conceptualization) (Methodology) (Supervision) (Writing-review and editing)

Template-free synthesis of Se-nanorods-rGO nanocomposite for application in supercapacitors

Nanotechnology Reviews, 2019

Both selenium and reduced graphene oxide have low specific capacitance due to their chemical natu... more Both selenium and reduced graphene oxide have low specific capacitance due to their chemical nature. Nevertheless, their specific capacitance could be enhanced by hybridizing Se nanomaterials with reduced graphene oxide via formation of electrochemical double layer at their interfacial area. Therefore, novel Se-nanorods/rGO nanocomposite was successfully synthesized by template free hot reflux route starting with graphene oxide and selenium dichloride. The composite of rGO decorated by Se-nanorods is characterized using X-ray diffractometry (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption– desorption. The unique architecture of the composite exhibits high specific capacitance of 390 F/ g at 5 mV/s scan rate in 1.0 M KOH solution with ~ 90% cyclic stability after 5000 cycles making it very promising electrode material for...

$Research paper thumbnail of {"__content__"=>"Surfactant/organic solvent free single-step engineering of hybrid graphene-Pt/TiO nanostructure: Efficient photocatalytic system for the treatment of wastewater coming from textile industries.", "sub"=>{"__content__"=>"2"}}$

{"__content__"=>"Surfactant/organic solvent free single-step engineering of hybrid graphene-Pt/TiO nanostructure: Efficient photocatalytic system for the treatment of wastewater coming from textile industries.", "sub"=>{"__content__"=>"2"}}

Scientific reports, Jan 2, 2018

In this study, hybrid graphene-Pt/TiO nanostructure were synthesized by single-step, inexpensive ... more In this study, hybrid graphene-Pt/TiO nanostructure were synthesized by single-step, inexpensive and surfactant/organic solvent free route; hydrothermal technique. The physicochemical properties of hybrid graphene-Pt/TiO nanostructure were carefully analyzed by multiple techniques, including X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The synthesized hybrid nanostructures were utilized as photocatalyst for the degradation of methylene blue (MB) dye under natural environment at average ambient temperature and mean daily global solar radiation, of about 22-25 °C and 374.9 mWh/cm, respectively. The activity performance indicated considerable degradation of methylene blue (MB) dye and was in the following order Gr (13%), TiO (60%) and hybrid graphene-Pt/TiO nanostructure (90%) over 21 min under the natural light illumination. The physiochemical characterization suggest...

Modeling the intrinsic viscosity of polydisperse disks

Journal of Rheology, 2017

In this work, we model the rheology of dilute colloidal oblate spheroids in their high aspect rat... more In this work, we model the rheology of dilute colloidal oblate spheroids in their high aspect ratio limit of circular disks. Theoretical models for the intrinsic viscosity, [g], of disks in shear flow are reviewed: The shear-independent, monodisperse Kuhn-Kuhn model, its polydisperse form by van der Kooij, and the shear-dependent models of Stewart and Sorenson, Leal and Hinch, and Brenner. Based on these previous works, three analytical models are introduced to describe the shear response over the entire range of practically accessible rotational Peclet numbers (Pe) and aspect ratios. Using the fact that [g] is linearly additive for sufficiently dilute systems we derive a general expression for polydisperse disks as a function of the two independent variables of particle diameter D and thickness t, that is, assuming D and t to be uncorrelated independent variables. We then argue for continuum modeling being preferable to discrete for using rheological measurements to estimate particle size distribution parameters. Computational results are shown for the continuum model in shear flow and generalized to uniaxial and planar extension, as well as to different particle distributions such as lognormal, normal, and bimodal. Finally, a modified form of [g], which we describe as innate viscosity (g), is suggested as an alternative method of modeling rheology of dilute dispersions.

Efficient removal of different basic dyes using graphene

DESALINATION AND WATER TREATMENT, 2017

This publication details the four major phases of analytical development work, coupled with sever... more This publication details the four major phases of analytical development work, coupled with several additional side studies, undertaken by the Office of Law Enforcement Standards in writing the Flexible Armor Conditioning Protocol in NIJ Standard-0101.06. This protocol partially fulfills a requirement to develop a revised performance standard for body armor to address a number of concerns, one of which was the ability of the armor to withstand environmental and wear conditions that an armor might see over its lifetime. This document details how the protocol was shortened from 9 weeks in the first phase of development to 10 days, as it appears in the current version of the standard. All major classes of ballistic materials were tested in the protocol development. The conditions selected are found to be quite detrimental to armors of a design that previously had problems in the field, but are not detrimental to armors of known good design. It is important to note that the protocol does not represent an exact period of time in the field, but efforts to correlate the protocol to a period of time in the field are the subject of future research.

Effect of Thermally Reduced Graphene on the Characteristics and Performance of Polysulfone Mixed Matrix Ultrafiltration Membranes

Membranes, Aug 20, 2023

Ultrafiltration (UF) polymeric membranes are widely used in water treatment and support desalinat... more Ultrafiltration (UF) polymeric membranes are widely used in water treatment and support desalination and gas separation membranes. In this article, we enhance the performance of Polysulfone (PSF) mixed matrix membranes (MMMs) by dispersing different concentrations of thermally reduced graphene (TRG) nanofillers. The UF PSF-TRG MMMs were fabricated via the phase inversion process, and the impact of TRG loading on the characteristics of the membrane, including hydrophilicity, porosity, roughness, and morphology, were analyzed using a contact angle measurement, atomic force microscopy (AFM), scanning electron microscopy (SEM), and dynamic mechanical analysis. Incorporating TRG into the PSF matrix led to favorable effects in the instantaneous de-mixing during phase inversion, increasing the porosity and hydrophilicity of MMMs and improving the mechanical properties of the membranes. Moreover, membrane performance was examined to remove dispersed oil from oil-water emulsion and support air-dehumidification membranes. MMM performance in terms of flux and oil rejection was superior to the control PSF membrane. Incorporating 0.25% TRG into PSF resulted in a 70% water flux increase and higher oil rejection compared to the control PSF membrane. As a support for air-dehumidification membranes, the MMM also demonstrated enhanced humidity reduction and an over 20% increase in water vapor permeance over the control PSF membrane. These results indicate that the PSF-TRG MMMs are an excellent candidate for reliable oil-water separation and as a support for air-dehumidification membranes.

A new series-parallel hybrid electric vehicle configuration based on an induction motor coupled to a DC machine

Scientific Research and Essays, Dec 31, 2010

With emphasis on a cleaner environment and efficient operation, vehicles today rely more and more... more With emphasis on a cleaner environment and efficient operation, vehicles today rely more and more heavily on electrical power generation for success. In this paper, to improve the speed performance of the drive against uncertainties caused by load disturbances, an integral switching surface couple mode speed controller was proposed. As such, mathematical modeling of the HEV components as the three phase induction motor coupled to the DC motor in hybrid electric vehicle was introduced. The controller of the 'induction motor' (IM) was designed based on input-output feedback linearization technique. It allowed greater electrical generation capacity and the fuel economy and emissions benefits of hybrid electric automotive propulsion. Hybrids transient torque allows the use of start/stop operation as well as brake energy regeneration. Thus, the results of Matlab-Simulink simulations and a comparison between the control schemes are presented.

Mesoporous PbO nanoparticle-catalyzed synthesis of arylbenzodioxy xanthenedione scaffolds under solvent-free conditions in a ball mill

RSC Advances, 2019

An efficient one-pot multicomponent protocol was developed for the synthesis of arylbenzodioxy xa... more

Rheology control by modulating hydrophobic and inclusive associations of side-groups in poly (acrylic acid)

Asia-Pacific Journal of Chemical Engineering, 2009

ABSTRACT

Facile In Situ Fabrication of Nanostructured Graphene–CuO Hybrid with Hydrogen Sulfide Removal Capacity

Nano-Micro Letters, 2016

A simple and scalable synthetic approach for one-step synthesis of graphene-CuO (TRGC) nanocompos... more A simple and scalable synthetic approach for one-step synthesis of graphene-CuO (TRGC) nanocomposite by an in situ thermo-annealing method has been developed. Using graphene oxide (GO) and copper hydroxide as a precursors reagent, the reduction of GO and the uniform deposition of in situ formed CuO nanoparticles on graphene was simultaneously achieved. The method employed no solvents, toxic-reducing agents, or organic modifiers. The resulting nanostructured hybrid exhibited improved H 2 S sorption capacity of 1.5 mmol H 2 S/g-sorbent (3 g S/100 g-sorbent). Due to its highly dispersed sub-20 nm CuO nanoparticles and large specific surface area, TRGC nanocomposite exhibits tremendous potential for energy and environment applications.

In situ formed graphene/ZnO nanostructured composites for low temperature hydrogen sulfide removal from natural gas

RSC Advances, 2016

Nanostructured composites of graphene and highly dispersed sub-20 nm sized ZnO nanoparticles (TRG... more

Polymer membranes for acid gas removal from natural gas

Separation and Purification Technology, 2016

The use of polymeric membrane technology is an exciting approach towards the removal of acid gase... more The use of polymeric membrane technology is an exciting approach towards the removal of acid gases, namely, carbon dioxide and hydrogen sulfide, from natural gas streams. Polymer membranes exhibit good mechanical, thermal and chemical stabilities. These membrane materials can also possess desirable transport properties such as high permeability and selectivity. A number of studies have attempted to improve these properties without compromising the advantages of existing technologies. Various preparations and structures of polymer membranes were reviewed. The structure-property analyses of these polymer membranes used for acid gas removal followed by their selectivity-permeability relationship and economic aspects are considered here.

Recent advances in graphene based gas sensors

Sensors and Actuators B: Chemical, 2015

ABSTRACT

Compositions Including Poly (Hydroxyalkanoates) and Graphene

Polymerization Method for Formation of Thermally Exfoliated Graphite Oxide Containing Polymer

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIW US007659350B2 (12) United States Patent ao) Pa... more IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIW US007659350B2 (12) United States Patent ao) Patent no.: us 7,659,350 B2 Prud'Homme et al. (45) Date of Patent: Feb. 9,2010 (54) POLYMERIZATION METHOD FOR FORMATION OF THERMALLY EXFOLIATED GRAPHITE OXIDE CONTAINING POLYMER (75) Inventors: Robert K. Prud'Homme, Lawrenceville, NJ (US); Ilium A. Aksay, Princeton, NJ (US); Douglas Adamson, Skillman, NJ (US) (73) Assignee: The Trustees of Princeton University, Princeton, NJ (US) ( * ) Notice: Subject to any disclaimer, the term of this patent ...

Thermally Conductive Polyethylene/Expanded Graphite Composites as Heat Transfer Surface: Mechanical, Thermo-Physical and Surface Behavior

Polymers, 2020

Composites of high-density polyethylene (HDPE) and expanded graphite (EG) are prepared for heat e... more Composites of high-density polyethylene (HDPE) and expanded graphite (EG) are prepared for heat exchangers in multi-effect distillation (MED) desalination. At 50 wt.% EG loading, the thermal conductivity of HDPE was increased by 372%. Moreover, the surface wettability of the HDPE/EG composite was enhanced by corona and RF plasma treatment as demonstrated by the increase in surface free energy from 28.5 mJ/m2 for untreated HDPE/EG to 55.5 and 54.5 mJ/m2 for HDPE/EG treated by corona and RF plasma, respectively. This enhanced surface wettability was retained over a long time with only a 9% and 18% decrease in RF and corona plasma-treated samples’ surface energy after two months. The viscoelastic moduli and the complex viscosity profiles indicated that EG content dictates the optimum processing technique. At loading below 30 wt.%, the extrusion process is preferred, while above 30 wt.% loading, injection molding is preferred. The plasma treatment also improved the HDPE/EG composite ove...

Developing Hydrophobic Graphene Foam for Oil Spill Cleanup

Industrial & Engineering Chemistry Research, 2017

Oil spills have been responsible for a number of environmental problems such as water pollution, ... more Oil spills have been responsible for a number of environmental problems such as water pollution, subsequent danger to aquatic life along with massive oil losses. Such disasters have stimulated the need for development of novel materials with improved sorption capacity for oil-spill cleanup. Among various available methods, the use of adsorbents holds great promises to remove and recover oil from minor or major spills. In the present work, we report the development of hydrothermally-reduced graphene oxide foam (RGO) functionalized with, Fe 3 O 4 , magnetic nanoparticles (MNP) for sorption of oil. Magnetic nanoparticles were used to produce RGO-MNP hybrid foams which could be separated by a magnetic field. The synthesized RGO and RGO-MNP hybrid foams were characterized by using Fourier Transform Infrared spectroscopy (FTIR), Raman spectroscopy, X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA). Motor oil was used as the adsorbate to determine the sorption capacity of the produced foams. Experimental results revealed that graphene foam is an excellent candidate to be used as a sorbent for oil spill cleanup due to its high specific surface area and hydrophobicity.

Adsorptive Removal of Azithromycin Antibiotic from Aqueous Solution by Azolla Filiculoides-Based Activated Porous Carbon

Nanomaterials, 2021

Due to the shortage of freshwater availability, reclaimed water has become an important source of... more Due to the shortage of freshwater availability, reclaimed water has become an important source of irrigation water. Nevertheless, emergent contaminants such as antibiotics in reclaimed water can cause potential health risks because antibiotics are nonbiodegradable. In this paper, we report the adsorptive removal of azithromycin (AZM) antibiotics using activated porous carbon prepared from Azolla filiculoides (AF) (AFAC). The influence of the adsorption process variables, such as temperature, pH, time, and adsorbent dosage, is investigated and described. The prepared AFAC is very effective in removing AZM with 87% and 98% removal after the treatment of 75 min, at 303 and 333 K, respectively. The Langmuir, Temkin, Freundlich, and Dubinin–Radushkevich isotherm models were used to analyze the adsorption results. The Freundlich isotherm was best to describe the adsorption isotherm. The adsorption process follows second-order pseudo kinetics. The adsorption was endothermic (ΔH°= 32.25 kJ/...

Thermally enhanced pristine polyolefins: fundamentals, progress and prospective

Journal of Materials Research and Technology, 2020

The low thermal conductivity of polymers hinders their use in applications requiring high thermal... more The low thermal conductivity of polymers hinders their use in applications requiring high thermal conductivity such as electronic packaging, heat exchangers, and thermal management devices. Polyethylene and polypropylene (polyolefins) account for ∼55% of the global thermoplastic production. Improving the thermal conductivity of this class of thermoplastics is important for many applications. This comprehensive review analyzes the advances on enhancing the thermal conductivity of pristine polyolefins. First, the mechanism of thermal transport in polymers and the key parameters that govern conductive heat transfer through polymers are discussed. Moreover, the progress in modeling and simulation of thermal conductivity of polyolefins are analyzed. Furthermore, the different approaches to enhance the thermal conductivity of polyolefins through controlling their microstructure, crystallinity and chain orientation are presented. Finally, the key challenges and prospective directions for developing thermally enhanced pristine polyolefins are outlined.

Data on characterization and performance of aspartic acid functionalized graphene oxide-polysulfone mixed matrix membranes

Data in Brief, 2020

Structure and microstructure characterization are very important for determining the membrane hyd... more Structure and microstructure characterization are very important for determining the membrane hydrophilicity, morphology, porosity, and mechanical properties that affect the membrane separation performance and durability. This article analyzes the morphological differences between graphene oxide (GO) and functionalized graphene oxide (f-GO) based on data from SEM imaging. nalysis of the morphology of mixed matrix membrane (MMMs) through SEM, mechanical properties through DMA and hydrophilicity through contact angle data. This dataset will support the original research article "Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-water emulsion separation" (Abdalla, Wahab and Abdala, 2020; doi.

Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-water emulsion separation

Journal of Environmental Chemical Engineering, 2020

Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-wa... more Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-water emulsion separation Omnya Abdalla (Investigation) (Formal analysis) (Visualization) (Writing-original draft), Md A. Wahab (Validation) (Writing-review and editing) (Formal analysis), Ahmed Abdala (Funding acquisition) (Conceptualization) (Methodology) (Supervision) (Writing-review and editing)

Template-free synthesis of Se-nanorods-rGO nanocomposite for application in supercapacitors

Nanotechnology Reviews, 2019

Both selenium and reduced graphene oxide have low specific capacitance due to their chemical natu... more Both selenium and reduced graphene oxide have low specific capacitance due to their chemical nature. Nevertheless, their specific capacitance could be enhanced by hybridizing Se nanomaterials with reduced graphene oxide via formation of electrochemical double layer at their interfacial area. Therefore, novel Se-nanorods/rGO nanocomposite was successfully synthesized by template free hot reflux route starting with graphene oxide and selenium dichloride. The composite of rGO decorated by Se-nanorods is characterized using X-ray diffractometry (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption– desorption. The unique architecture of the composite exhibits high specific capacitance of 390 F/ g at 5 mV/s scan rate in 1.0 M KOH solution with ~ 90% cyclic stability after 5000 cycles making it very promising electrode material for...

$Research paper thumbnail of {"__content__"=>"Surfactant/organic solvent free single-step engineering of hybrid graphene-Pt/TiO nanostructure: Efficient photocatalytic system for the treatment of wastewater coming from textile industries.", "sub"=>{"__content__"=>"2"}}$

{"__content__"=>"Surfactant/organic solvent free single-step engineering of hybrid graphene-Pt/TiO nanostructure: Efficient photocatalytic system for the treatment of wastewater coming from textile industries.", "sub"=>{"__content__"=>"2"}}

Scientific reports, Jan 2, 2018

In this study, hybrid graphene-Pt/TiO nanostructure were synthesized by single-step, inexpensive ... more In this study, hybrid graphene-Pt/TiO nanostructure were synthesized by single-step, inexpensive and surfactant/organic solvent free route; hydrothermal technique. The physicochemical properties of hybrid graphene-Pt/TiO nanostructure were carefully analyzed by multiple techniques, including X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The synthesized hybrid nanostructures were utilized as photocatalyst for the degradation of methylene blue (MB) dye under natural environment at average ambient temperature and mean daily global solar radiation, of about 22-25 °C and 374.9 mWh/cm, respectively. The activity performance indicated considerable degradation of methylene blue (MB) dye and was in the following order Gr (13%), TiO (60%) and hybrid graphene-Pt/TiO nanostructure (90%) over 21 min under the natural light illumination. The physiochemical characterization suggest...

Modeling the intrinsic viscosity of polydisperse disks

Journal of Rheology, 2017

In this work, we model the rheology of dilute colloidal oblate spheroids in their high aspect rat... more In this work, we model the rheology of dilute colloidal oblate spheroids in their high aspect ratio limit of circular disks. Theoretical models for the intrinsic viscosity, [g], of disks in shear flow are reviewed: The shear-independent, monodisperse Kuhn-Kuhn model, its polydisperse form by van der Kooij, and the shear-dependent models of Stewart and Sorenson, Leal and Hinch, and Brenner. Based on these previous works, three analytical models are introduced to describe the shear response over the entire range of practically accessible rotational Peclet numbers (Pe) and aspect ratios. Using the fact that [g] is linearly additive for sufficiently dilute systems we derive a general expression for polydisperse disks as a function of the two independent variables of particle diameter D and thickness t, that is, assuming D and t to be uncorrelated independent variables. We then argue for continuum modeling being preferable to discrete for using rheological measurements to estimate particle size distribution parameters. Computational results are shown for the continuum model in shear flow and generalized to uniaxial and planar extension, as well as to different particle distributions such as lognormal, normal, and bimodal. Finally, a modified form of [g], which we describe as innate viscosity (g), is suggested as an alternative method of modeling rheology of dilute dispersions.

Efficient removal of different basic dyes using graphene

DESALINATION AND WATER TREATMENT, 2017

This publication details the four major phases of analytical development work, coupled with sever... more This publication details the four major phases of analytical development work, coupled with several additional side studies, undertaken by the Office of Law Enforcement Standards in writing the Flexible Armor Conditioning Protocol in NIJ Standard-0101.06. This protocol partially fulfills a requirement to develop a revised performance standard for body armor to address a number of concerns, one of which was the ability of the armor to withstand environmental and wear conditions that an armor might see over its lifetime. This document details how the protocol was shortened from 9 weeks in the first phase of development to 10 days, as it appears in the current version of the standard. All major classes of ballistic materials were tested in the protocol development. The conditions selected are found to be quite detrimental to armors of a design that previously had problems in the field, but are not detrimental to armors of known good design. It is important to note that the protocol does not represent an exact period of time in the field, but efforts to correlate the protocol to a period of time in the field are the subject of future research.

CHEG587: Polymer Nanocomposites. Summer 2012

CHEG481: Gas Processing Engineering. Spring 2012

CHEG411: Chemical Reaction Engineering. Fall 2013

CHEG511: Advanced Reaction Engineering. Spring 2013

CHEG421: Petroleum Refining and Processing. Fall 2008

CHEG351: Mass Transfer. Spring 2008

CHEG411: Chemical Reaction Engineeirng. Fall 2010

 This course focuses in the chemical processes part where chemical reactions take place  It foc... more  This course focuses in the chemical processes part where chemical reactions take place  It focuses mainly on the design of the vessels where these reactions occur, i.e. the chemical reactors  We do not, however, focus on the mechanical design of the reactor CHEG411: Chemical Reaction Engineering Course Objectives  The aim of the course is to answer the following questions: 1. Will a certain reaction take place under certain conditions (temperature, pressure and catalyst)?