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In the present work, continuous fixed-bed column and batch studies were undertaken to investigate the efficiency of iron-based metal–organic framework (Fe-BTC) for the removal of methyl orange as a model contaminant from aqueous solutions. The batch experiments were carried out by varying operational parameters such as adsorbent dosage, pH, temperature, and initial contaminant concentration. The results showed that Fe-BTC had a high removal efficiency under a wide pH range. The equilibrium data were best fitted by the Langmuir model with a maximum adsorption capacity of 100.3 mg g-1 at 298 K. In order to assess the industrial feasibility of Fe-BTC, fixed-bed column studies were conducted to obtain breakthrough curves, breakthrough and saturation times, and maximum uptakes at different bed heights. The breakthrough time was 20.0 and 46.2 h at 0.75 and 1.5 cm bed depths, respectively. The bed removal efficiency was 35.2 and 46.7% at 0.75 and 1.5 cm bed depth, respectively. The bed maximum adsorption capacity was 20.2 and 21.6 mg/g at 0.75 and 1.5 cm bed depths, respectively. Moreover, the application of empirical breakthrough curve models showed good agreement with the modified dose response model (R2> 0.99). Also, the analytical solution of the advection–dispersion–adsorption mass transfer equation showed an excellent fit to the experimental breakthrough data (R2> 0.99). Further, the analytical model was utilized to predict the length of the mass transfer zone as a function of the bed depth and to construct a 3D surface plot that can be utilized to predict the breakthrough at different bed depths.

A Master of Science thesis in Chemical Engineering by Abdollah Karami entitled, “Adsorptive Removal of Dyes from Aqueous Solutions Using Metal Organic Frameworks (MOFs)”, submitted in April 2019. Thesis advisor is Dr. Rana Sabouni and thesis co-advisor is Dr. Ahmed Aidan. Soft and hard copy available., College of Engineering, Department of Chemical Engineering

A Master of Science thesis in Chemical Engineering by Noora Hussein Adam Mukhtar entitled, “Membrane Bioreactor-Desalination Microbial Fuel Cell Hybrid System”, submitted in April 2018. Thesis advisor is Dr. Sameer Al-Asheh and thesis co-advisor is Dr. Ahmed A. Aidan. Soft and hard copy available., The microbial desalination fuel cell (MDFC) is an emerging desalination technology offering great promise of high salinity removal with zero energy input. Moreover, the membrane bioreactor (MBR) is of great reliability in treating domestic and industrial wastewater. The objective of this work is to introduce a hybrid system of a membrane bioreactor and a microbial desalination fuel cell for simultaneous wastewater treatment, seawater desalination and production of electricity. This hybrid system allows low cost resources, energy conservation and low sludge and carbon footprints. Synthetic wastewater, exoelectrogenic microorganisms (yeast) and substrate (glucose) were employed as the anode feed in the MDFC. Two system configurations with an immersed MBR and side-stream MBR have been proposed and compared. In addition, the hybrid system was studied under open circuit (no external load) and closed circuit modes (three different resistive loads). This research presents the success of the hybridization in comparison with a MDFC employing only yeast solution as the anolyte. In addition, it investigates the effect of some modifications namely, the cell size, solutions volume ratio and type of ion exchange membrane. Experimental tests revealed that a bench scale system of 350-ml chamber capacity can achieve higher salinity removal (+6%) and voltage production (+0.035 V) than its alternative 4500-ml chamber. Also, reducing the volume of seawater to anolyte and catholyte volumes by 29% accomplished higher desalination by 6% for the hybrid system removing almost 20% of the salts in 8 days. A total desalination rate (TDR) of 6.25 mg/hr, and a power density of 4.34×10-3 W/m3 are obtained using a 300-KΩ external resistance. On the other hand, a power density of 0.222 W/m3 and 4.69 mg/hr TDR are achieved using a 4-KΩ external load. Thus, the choice of external resistance involves a trade-off between desalination efficiency and power generation. With regards to wastewater treatment, College of Engineering, Department of Chemical Engineering

A Master of Science thesis in Chemical Engineering by Apoorva Goel entitled, “Produced water treatment using microbial desalination cells”, submitted in May 2018. Thesis advisor is Dr. Naif Darwish and thesis co-advisor is Dr. Ahmed Aidan. Soft and hard copy available., Globally, 250 million barrels of produced water is generated daily for extracting 80 million barrels of oil. Having a highly variable composition and no economic value, produced water presents serious environmental problems. While the treatment of produced water is of paramount concern, existing desalination technologies are highly expensive and energy-intensive leading to great investments by oil industries. Microbial desalination cells (MDC) provide a promising alternative through their potential for negligible energy input, use of low-cost resources, low waste production, and electricity generation. However, MDC is a relatively new technology and its application in industries is limited by its low desalination efficiency and pH instability. This research investigates the effect of various factors on the performance of MDC employing Saccharomyces cerevisiae yeast as electron generating microorganisms. Two mediators, methylene blue, and menadione are used as electron promoters to shuttle the electrons from the yeast cells to the anode electrode. In particular, a two-level partial factorial design is implemented where, MDC desalination efficiency is investigated at two (low/high) levels of three input factors: aeration in anolyte (aerobic/ anaerobic), hydrophilic mediator concentration (0.5– 2 mM), and concentration of Total Dissolved Solids (TDS) in produced water (20– 40 g/l). Acquired experimental data are statistically analyzed using single effect and interaction plots. In addition, several other operating parameters and configurations are investigated in order to achieve optimum conditions for best performance. These include aeration rates in the anode and cathode chambers, the concentration of lipophilic and hydrophilic mediators, the pH of the anolyte solution, the use of activated carbon granules, and the repeated batch operation. Moreover, an MDC unit is operated at the optimized conditions where it resulted in 36% desalination after 72 hours. The study rev, College of Engineering, Department of Chemical Engineering

A Master of Science thesis in Chemical Engineering by Noun Abdelwahab entitled, “Effects of Operating Conditions on Water Absorption Capacity of Superabsorbent Hydrogels”, submitted in April 2018. Thesis advisor is Dr. Naif Darwish and thesis co-advisor is Dr. Ahmed Aidan. Soft and hard copy available., Superabsorbent hydrogels are three-dimensional networks of hydrophilic polymers that have an extraordinary ability to absorb and retain water. Therefore, they have been utilized in many applications such as disposal diapers, drug delivery, and water desalination. In this study, the effects of environmental and synthetic parameters on the absorbency of superabsorbent hydrogels are investigated using a two-level factorial design. Commercial hydrogels were used to examine the effects of temperature, swelling time, pH, and hydrogel amount, whereas synthesized poly acrylamide hydrogels were used to study the effects of monomer, cross-linker, and initiator concentrations. Moreover, both commercial and synthesized hydrogels were characterized using Fourier transform infrared (FTIR) spectroscopy. Higher absorbency is obtained for the commercial hydrogels by increasing the swelling time from two to eight hours. A reduction of 2.8 g/g(g water/g hydrogel) was observed by increasing the level of pH from 8.5 to 10. Water absorption capacity of the hydrogel increased by 14.72 g/g upon increasing the temperature by 8.5oC above room temperature. For the synthesized hydrogel, it was found that increasing monomer concentration by 5% reduces absorbency by 2.51g/g, whereas increasing cross-linkers concentrations from 0.5% to 1.75% decreases the absorbency by 3.01g/g. Increasing the concentration of the initiator by 0.2% was found to improve absorbency by 0.98g/g. The results show that time, temperature, and monomers have positive effects on absorbency while pH, cross-linkers and initiators reduce it., College of Engineering, Department of Chemical Engineering

This report studies the performance of a Microbial Desalination Cell (MDC) in the presence ofactivated carbon in both the cathode and anode chambers. The large surface area of the activatedcarbon provides surface for bacterial growth, thereby leading to the formation of a stronger microbialculture through the formation of a biofilm. An MDC of 60 ml total capacity is used to achieve60 percent desalination within 20 hours. In addition, a maximum mean voltage of 105 mV and apower density of 1.546 mW/m2 are obtained when a 3.2-k resistor was used. The results of ourexperiments suggest that the addition of activated carbon to the anodic and cathodic chambersimproves MDC performance. This technology has the potential to be used to integrate a wastewater treatment plant and a desalination facility.

A Master of Science thesis in Chemical Engineering by Ryan K. Altayeb entitled, "Liquid Fuel Production from Pyrolysis of Waste Tires: Process Simulation, Exergetic Analysis, and Life Cycle Assessment," submitted in June 2015. Thesis advisor is Dr. Taleb Ibrahim, thesis co-advisors are Dr. Ahmed Aidan and Dr. Nabil Abdel Jabbar. Soft and hard copy available., Scrap tire is considered to be one of the very common and significant solid wastes and its production is increasing due to the increased number of vehicles in both developed and developing countries. Initiatives are being taken to overcome the fossil fuel crisis by looking for alternatives to replace gasoline and diesel fuel. This work presents the simulation of waste tires pyrolysis process in ASPEN Plus® 8.4 where the effect of temperature on the pyrolytic oil yield was investigated. It is shown that the optimum temperature for waste tire pyrolysis in a rotary kiln reactor is around 450-550oC. Also, an exergetic analysis of the pyrolysis reactor was performed to study the performance of the process. The overall exergetic efficiency of the reactor was found to be 69.9% which is equivalent to an exergy destruction of 30.1% due to process irreversibility. Finally, life cycle assessment of the process using SimaPro 7.3.2 was conducted to find out if the process of waste tire pyrolysis is environmentally friendly. The results showed that the pyrolysis process can be considered environmentally friendly but there is room for improvement. A sensitivity analysis was conducted to investigate the effect of changing the heating fuel in the process where non-condensable gases produced in the process were utilized for heating purposes. The results showed a significant reduction on the environmental impacts due to the reduction of hazardous emissions from the process., College of Engineering, Department of Chemical Engineering

A Master of Science thesis in Chemical Engineering by Muna Al Mazrooei entitled, "Modeling Water Flux in Forward Osmosis: Implications for Improved Membrane Design," submitted in May 2013. Thesis advisor is Dr. Raafat Alnaizy and co-advisor is Dr. Ahmed Aidan. Available are both soft and hard copies of the thesis., In efforts to make fresh water available to all people, researchers are dedicated to establish a water treatment method that will reduce the cost of production and impact on the environment. Forward osmosis desalination has been under the spotlight as a candidate of being a revolutionary water treatment method. Nevertheless, forward osmosis is faced with obstacles that hinder it from being commercially available. One of the main forward osmosis problems is low flux induced by concentration polarization and inadequate membrane design. To examine the problem, a commercially available forward osmosis membrane was tested using two different draw solutions. Using different feed solutions, experimental flux was determined and flux modeling was performed for the system in hand. The flux model selected was a good fit to experimental data for all draw solutions used; NaCl, magnesium sulfate and copper sulfate. The model was tested on our experimental data and other researchers' data. The flux model was found to be in line with experimental data for all systems at various operating conditions. It was found that dilutive internal concentration polarization (ICP) had a significant impact on flux. The overall driving force was reduced by dilutive ICP which caused a substantial reduction in the flux. It was determined that to reduce Dilutive ICP, solute resistance to diffusion (K) had to be minimized. Results also indicated that minimizing solute resistance to diffusion (K) achieved higher flux. It was also concluded that concentrative external concentration polarization (ECP) had a minor impact on flux. Varying feed mass transfer coefficient, a factor controlling concentrative ECP, had a small effect on flux. Magnesium sulfate and copper sulfate draw solutions were compared in terms of flux; it was found that coppers sulfate generates higher flux., College of Engineering, Department of Chemical Engineering

A Master of Science thesis in Chemical Engineering by Mohammed Al Jabari entitled, "Spent Caustic Treatment Using Advanced Oxidation Processes," submitted in May 2012. Thesis advisor is Dr. Raafat Alnaizy. Available are both soft and hard copies of the thesis., Mixed refinery spent caustic is an industrial wastewater that is generated from oil refineries. Spent caustic undergo two treatment steps, chemical oxidation followed by biological post treatment step. The goal of chemical oxidation is to drop the contamination concentration to a level that biological treatment can take place. The maximum contaminants concentration, which can be measured by chemical oxygen demand, that biological treatment can be applied, is 1,000 ppm. Advanced oxidation processes, in specific, fenton's reaction is tested to check if the method can be applied to spent caustic treatment. The research is divided into two parts, bench scale study followed by pilot plant study. The goal of bench scale study is to treat spent caustic to achieve a final chemical oxygen demand of 1,000 ppm with minimum hydrogen peroxide to chemical oxygen demand ratio possible by manipulating other factors affecting chemical oxygen demand removal. It was found out that the highest chemical oxygen demand removal achieved is 97% at optimum hydrogen peroxide to ferrous sulfate to chemical oxygen demand mass ratio of 3.8/2.1/1. Moving on to the pilot plant study, the objective of the pilot plant study is to check if fenton's process can be applied in large scale. The best result obtained is a final chemical oxygen demand of 525 ppm while operating at hydrogen peroxide to ferrous sulfate to chemical oxygen demand mass ratio of 3.5/1.6/1., College of Engineering, Department of Chemical Engineering