Qatar Foundation Annual Research Conference Proceedings Volume 2018 Issue 1

The State of Qatar and the Gulf Cooperation Council (GCC) region are located in a hyper-arid area with no rivers, over-abstracted groundwater supply and limited rainfall. Consequently, with the discovery of oil and gas and the associated economic prosperity, the State of Qatar and the GCC region have relied on desalination of seawater from the Arabian Gulf. As of 2013, the GCC region held a 70% share of total global desalination capacity.Multi-Stage Flash (MSF) desalination technology has been the source of water supply in the State of Qatar and the GCC region for the past few decades due to the low cost of energy in these countries and the problems historically faced by Reverse Osmosis (RO) membrane processes in dealing wih the high salinity of the Arabian Gulf. MSF is a thermal process that distills water through stages based on high temperature and changing pressures. The systems suffer from high energy requirements and low recovery rates resulting in significant discharge of brine with elevated temperature to the ambient receiving water. RO on the other hand relies on applying a positive pressure to pass permeate through a fine polymer filter material against the osmotic pressure gradient. RO is widely adopted worldwide due to its lower energy consumption and increased product recovery. With recent developments the technology can cover the high salinity of the Arabian Gulf (40,000 mg/L to 55,000 mg/L total dissolved solids). Nevertheless, RO systems require extensive pretreatment to ensure the integrity of the membrane and to prevent blocking of the fine pores. This makes the process susceptible to surface water quality fluctuations such as during algal blooms and therefore its application in Qatar is still challenging due to the shallow and enclosed nature of the Arabian Gulf.Subsurface intake processes for RO have the potential to reduce the effects of fluctuations in source water quality and reduce the energy intensity of the process, since they provide natural filtration of the source water and simplify the extensive pretreatment requirements necessary to protect the RO membranes. However, significant tradeoffs occur by using subsurface intakes. For instance, intake pumping may be increased to overcome the additional headloss through the intake media while the construction phase also involves increased civil works. This research investigates the environmental impacts associated with the operation phase of RO systems using both open intake and beach well intake systems theoretically located in the State of Qatar, since operational phase impacts typically comprise most of the environmental loads in cradle-to-grave assessments.The study utilizes Life Cycle Assessment (LCA) methodology to assess a wide range of effects from the systems. The ReCiPe lifecycle impact indicator approach is utilized with mid-point impact indicators including climate change, marine eutrophication, terrestial acidification, photochemical oxidant formation, particulate matter formation, marine ecotoxicity, water depletion, mineral resource depletion and fossil fuel depletion. The RO system, its pretreatment and intake will be sized and modelled for a desalinated water output of 100,000 m3/d using a combination of fundamental process equations and commercially available software. The results will show a clear direction from an environmental perspective on which type of intake system Qatar should consider if implementing seawater RO as a preferred desalination technique.

Sulfate Reducing Bacteria (SRB) cause significant damage to marine oil pipelines necessitating the use of biocides for reducing the Microbial Induced Corrosion (MIC) and potential for great environmental harm. Currently, oil companies pump frequent batches of biocides to these under water pipelines without proper quantification of the bacterial population. This is primarily because the existing method for quantifying the bacterial population in a sample is not very effecient, as it can take up to 2 weeks to obtain the results. Our team has focused on developing an eco-friendly approach to limit the use of these biocides, which are used for targeting the SRB. SRB require high salt and low oxygen so first we genetically engineered a strain of bacteria that would report the osmolarity in oil pipelines, thus act as a biosensor for salt concentrations. The ratio of salinity in the seawater flowing in versus the seawater flowing out of the well will be used to estimate SRB populations in the pipelines, thus limiting the amount of biocides added in times of high Microbial counts.

Carbonates and evaporites of Paleogene-age form the shallow-aquifer rocks that mantle most of Qatar, including the Paleocene and Lower Eocene Umm er Radhuma, and the Middle Eocene Rus and Dammam Formations. Nearly complete 10-cm-diameter rock cores have been recovered from boreholes in central and northern Qatar to depths of greater than 120 m. A 40-m section of exposed Rus and Dammam Formation from a cave in central Qatar (Misfer Cave) was also described. Assessment of aquifer quality in these rocks was undertaken through core and thin-section description, quantitative mineralogical determination (X-ray diffraction), as well as core-plug porosity, permeability, and pore-throat (mercury-injection capillary pressure) measurements.

Our work shows that the rocks from central Qatar can be separated into four depositional intervals: 1) m-scale fining-upward cycles of fossiliferous open-marine deposits with clay-rich caps (Umm er Radhuma), 2) fine-grained stromatolite-bearing, restricted shallow-marine deposits (uppermost Umm er Radhuma), 3) m-scale bedded marginal-marine gypsum deposits intercalated with thin shallow marine carbonate and clay deposits and capped by rooted and microcodium-bearing surfaces (Rus Formation), and 4) open-marine carbonates overprinted by karst processes (Dammam). Aquifer storage capacity and hydraulic conductivity are mostly a function of diagenetic features, and in spite of the lack of any evidence of significant burial, the diagenesis of these rocks is complex. The Umm er Radhuma and the Rus carbonates are almost completely dolomitized, whereas the Dammam is only partially dolomitized, with the amount of dolomitization varying both laterally and vertically. Best aquifer quality in central Qatar, based both on core plug data and well spinner tests, can be found in coarsely-dolomitized intervals that lack clay (lower Umm er Radhuma). Finer and clay-bearing dolomitized rocks have storage but lower hydraulic conductivity (upper Umm er Radhuma). Both gypsum-rich rocks and depositional limestones (which are generally mud-bearing) have lower porosity and permeability (Rus and Dammam). In central Qatar the effect of karst overprinting is variable, generally leading to lower matrix porosity and permeability due to clay translocation from above, but large vugs are also observed at exposure surfaces.

The borehole in northern Qatar was located within a karst collapse feature (doline) that is characterized by internal drainage. Based on satellite images, the collapse feature, likely reflecting the presence of deeper karst is approximately 1 km in width. Sediment tentatively interpreted as a cave deposit, and composed mainly of dolomite silt, has been observed in this core at depths of greater than 60 m below the surface. This fine-grained material intercalates with courser breccias that are interpreted as collapsed country rock. The impact of karstification on country rock matrix properties (porosity and permeability) is still to be determined. Whereas the rocks from northern Qatar are still under investigation, they are distinct from the central Qatar equivalents in that they lack any bedded evaporites. This leads to the prediction that the shallow aquifer in northern Qatar will be less compartmentalized than in central Qatar. The elemental makeup of waters from different stratigraphic intervals in both boreholes are being compared to help understand how the central and north shallow Qatar aquifers contrast.

Lithium ion batteries (LIBs) have completely captured the portable electronics and electric vehicle market due to their tempting performance. However, due to limited reserves of lithium, the price for lithium is constantly increasing which necessitates to trace out some decent alternative to lithium ion batteries. In this regard, sodium ion batteries are considered one of the best substitutes for lithium ion batteries due to inherited properties of sodium metal like abundance of resources across the globe, ease of availability, economy and environmentally friendly nature. Moreover, sodium ion batteries follow the similar electrochemical principles as the lithium ion batteries which indicates that knowledge and understanding of principles of lithium ion batteries can be utilized for the development of smart sodium ion batteries. In this work NASICON (Na+ super ionic conductor) based Na4MnV (PO4) 3 was synthesized using the sol - gel technique. As prepared Na4MnV (PO4)3 demonstrates an active redox couple at around 3.6 V and 3.2 V during oxidation and reduction process respectively. The pristine Na4MnV(PO4)3 shows good initial discharge capacity ∼ 138 mAh g-1 at 0.05C. However, it shows rapid discharge capacity fading with increasing discharge rate (138 mAh/g at 0.05C and 15 mAh/g at 2C) and poor cycling performance (68.0% of the initial capacity was retained after 40 cycles) with increasing discharge rate. To improve the electrochemical performance of the developed material, Na4MnV (PO4)3/MWCNTS (MWCNTs = 1 & 3wt. %) were synthesized. The initial discharge capacity of these materials at 0.05C was found to be similar to pristine Na4MnV(PO4)3, however, the addition of MWCNTs has resulted in significant improvement in the discharge capacity at high c-rate which can be mainly attributed to the enhanced electronic conductivity of the pristine material. Apart from higher capacity at high c-rates, the addition of MWCNTs has also improved the cyclability of the pristine Na4MnV(PO4)3. A capacity retention of 99.0 % and 98.00% of the initial discharge capacity after 40 cycles is noticed for Na4MnV(PO4)3/1wt.%MWCNTs and Na4MnV(PO4)3/3wt.%MWCNTs respectively. The improved performance of Na4MnV (PO4) 3/MWCNTs cathode materails make them attractive for energystorage applications.

A common source of contamination of soil and groundwater in arid and (semi)-arid coastal regions are accidental spills of petroleum products, such as crude oil, gasoline, and diesel fuel. Groundwater pollution by petroleum hydrocarbons is a serious pollution problem that poses hazards to water resources and living organisms including humans. After release to the sub surface, hydrocarbons move downward through the aerobic vadose zone under the force of gravity. Eventually, they reach the groundwater table, where oil overlay promotes the development of anaerobic conditions. The oil phase that occurs as floating product on the water table and as residuum on soil grains provides a continued source supplying hydrocarbons to the groundwater. Accumulations of residual hydrocarbons at or near the water table may undergo smearing due to variations in water table elevation driven by, for example, seasonal changes in recharge and discharge or by tidal forcing in coastal environments. In subsurface environments contaminated by petroleum products, the geochemical conditions near the water table, in particular, the oxygen availability, moisture content, salinity, pH, nutrient concentrations and temperature, are important determinants of biogeochemical processes. Among these variables, the interplay of moisture content, oxygen availability and temperature are critical for understanding the biodegradation of petroleum hydrocarbons in arid and (semi)-arid coastal soil environments. In addition, the fate and transport of hydrocarbons in groundwater also depend on the redox conditions, soil mineralogy and microbial community structure, as well as the availability of suitable electron acceptors and nutrients. We hypothesize that the transition zone between the vadose zone and the groundwater system represents a hot spot for the degradation of petroleum hydrocarbons. This transition zone, however, is a dynamic biogeochemical environment, whose functioning is closely linked to the amplitude and frequency of water table fluctuations. We propose to determine the role of water table fluctuations on the coupled hydrological and biogeochemical processes that affect the degradation and partitioning of petroleum hydrocarbons, under conditions relevant to aquifers. Coastal areas in this regard can function as zones of contaminant mass transfers between aquifers and surface water bodies, but also as excellent spots of in situ bioremediation of contaminated soil and groundwater thanks to coupled hydrological and biogeochemical processes. The main objectives of this project are to: 1) quantify the level of sorption and biodegradation of multi-component hydrocarbons in soil and groundwater; 2) quantify the rates of hydrocarbon biodegradation under oscillating aerobic and sulfate reducing conditions in groundwater contaminated with petroleum hydrocarbons; 3) determine the oxygen dynamics in the vadose zone and groundwater affected by hydrocarbon dispersion under variable water table fluctuation regimes; 4) assess the rates and mechanisms of biogeochemical reactions regulating groundwater nutrient turnover during hydrocarbon spill and its movement under conditions of groundwater table fluctuations; and 5) develop a reactive transport model for groundwater pollution by petroleum hydrocarbons. In this project, we combine the acquisition of integrated physical, chemical and microbial data using uniquely designed process-oriented experimental approaches. The results of this project will significantly add to the quantitative knowledge on the effects of water table fluctuations on the release and degradation of petroleum-derived hydrocarbon contaminants in soil environments that experience both arid conditions and tidally-driven water table fluctuations. The expected results of the research will inform groundwater management and protection in arid and (semi)-arid coastal environments. To quantify the level of sorption and biodegradation of petroleum hydrocarbons in subsurface soils and groundwater (Objective 1), we conducted a series of controlled-laboratory batch experiments under variable salinity, temperature and water chemistry conditions. The soil samples were collected from the eastern coast of Qatar which is close to the North Gas and Al-Shaheen Oil Fields. The initial physical characterization of soil samples showed sand classification with the texture class of sabkhas soil. The results of soil-phase chemical characterization suggested that the dominant minerals of the soil are calcite, dolomite and gypsum and the concentrations of chloride and sodium were found to be high with a chloride-to-sodium ratio of ∼1.6.We used volatile benzene and naphthalene hydrocarbons to determine the sorption and biodegradation rates. The results of sorption experiments showed that naphthalene was adsorbed to the soil more than benzene where the initial aqueous concentrations of benzene and naphthalene were reduced at equilibrium due to sorption by approximately 10% and 75%, respectively. This difference was attributed to the organic carbon-water partitioning coefficient which is higher for naphthalene. We developed a sorption kinetics model to define the sorption isotherm of benzene and naphthalene hydrocarbons for the specific coastal soil collected from Qatar site. The model assumes the two sites sorption to the soil, one site in local equilibrium and the other site on first-order kinetic sorption, and the best fits were found for the Langmuir sorption isotherm type for the used hydrocarbons and soil in this project. In this presentation, we present the results of sorption and biodegradation batch experiments as well as the design of a unique dynamic soil column experiment to understand the dynamic responses of the fate, transport and degradation of hydrocarbons and the soil biogeochemical processes to the relatively abrupt changes in hydrogeochemical and climatic conditions.

Background A range of natural factors, invasive animals and human activity have been severely affecting stability of the ecosystem, resulting in the annihilation of plants habitats and so plant endangerment or even extinction. In Qatar, urgent action needs to be taken to stop decline of desert plant species as well as an effective strategy should be applied to reverse and save these wild endangered plants. Otherwise, they will be faced with the danger of their extinction in near future. Therefore, it is very important to have knowledge of protection measures, such as replanting and propagating through tissue culture technology, to protect the biodiversity in Qatar. Plant in-vitro culture systems have been used as an alternative approach to propagate and conserve a large number of rare and endangered plant species that show difficulties to be propagated using conventional methods of propagation. It was reported that standard culture environment could be effectively employed for short-term in-vitro conservation of different plant germplasm, through increasing intervals between subcultures especially in slow growing plant species. Objectives In the current study, conservation of rare and endangered desert plants using in-vitro culture were developed. Generally, these plants are not easy to be propagated by classical horticultural methods. Different techniques including micro-propagation, in vitro seed germination, and regeneration from callus were applied to propagate and conserve three endangered plant species in Qatar; Leptadenia pyrotechnica, Glossonema varians and Prosopis cineraria. Methods Collection of endangered plant species Location of the endangered plant species were identified and the plant parts- seeds, stem, shoots, roots, nodal cuttings or whole plant- depending on its type and availability, were collected. Surface sterilization of the collected material The plant materials were washed with tap water to remove dust and debris, then were soaked in 70% ethanol for 1–2 min, then were treated with sodium hypochlorite or Clorox for 10–20 min followed by rinsing 3–5 times with sterilized distilled water under aseptic conditions. In-vitro plants formation Organ culture using nodal sections of the plants were cultured on hormone-free MS medium (0.5X) for in vitro plants formation. For seeds were cultured on medium containing gibberellic acid (GA3) for efficient seeds germination. In this way, in vitro plants were established and multiplied to produce large number of healthy clones. In case seeds or nodal cuttings are not available, other plant parts like leaf or root were used as explants to initiate callus tissues. Results Seeds of Leptadenia pyrotechnica were collected, surface sterilized and germinated under aseptic condition using 0.5X MS media. In-vitro employing tissue culture via callus and shoot induction using different growth regulators was explored. Seedlings from in-vitro germination of the seed were used as explants. The results revealed that the highest callus production was obtained using 2.0 mg/L BAP. In addition, 0.5 mg/L and 2.0 mg/L NAA were good for callus initiation, compared to other hormones. Seedlings of Glossonema varians were collected were used as an explant for callus induction. Several plant growth regulator were used to initiate callus including 2, 4, D, NAA and BAP and their combinations. The results showed that the best plant growth regulators to induce callus were 1.5 mg/l IBA and 2 mg/l BAP. Prosopis cineraria, is a famous tree in Qatar. It is not easy to be propagated by classical horticultural methods. Seed dormancy was broken by scratching via sand paper. Several plant growth regulator were used to initiate callus including 2, 4, D, NAA and BAP and their combinations. The results showed that the best plant growth regulators to induce callus were both 2.0 mg/l 2, 4, D and 1.5 mg/l IBA. The obtained callus will be treated to regenerate new plantlets. Adventitious shoots and roots formation will be induced and a large number of in vitro plants will be produced. The in-vitro grown clones will be hardened (acclimatized) for greenhouse and later field conditions. The in-vitro plants will be removed from the cultures; medium will be removed by washing with running water and sown in pots. The pots will be covered with plastic sheets to keep high humidity and gradual removal of the plastic will harden the plants for greenhouse.Conclusions Recently, in-vitro culture technique of desert plants has received importance because it can be used for the fast propagation and ex situ conservation of endangered plants. The success of micro-propagation and in vitro conservation of the selected endangered plants depends on the best choice of the explants, the efficiency of the sterilization method and correct plant growth regulator. The best in-vitro conservation of the selected plant species is in MS media with the following plant hormones 2, 4, D, NAA. IBA and BAP.

Acknowledgements «This study was made possible by UREP grant # UREP19-209-1-037 from the Qatar national research fund (a member of Qatar foundation). The statements made herein are solely the responsibility of the author(s).»

A significant global environmental opportunity of today is finding beneficial reuse for industrial and domestic wastewater through appropriate treatment, redistribution and application. Although industrial wastewater may present various challenges in terms of exotic or hard to treat constituents, finding effective and efficient treatment options and subsequent reuse opportunities will be beneficial for many facets of the environment, especially in regions of the world where water scarcity is an issue. Numerous remediation methods have been developed to purify wastewater. Most of these are physiochemical in nature, which are often not effective to implement on a large scale and can be expensive. This research explores an environmentally natural approach using biological processes (microbial activity) to achieve the degradation of petroleum hydrocarbons. The objective of this study was to study microbes native to Qatar, in particular those found within microbial mats that are found in various areas around the country. The steps taken were to first estimate the area of microbial mats using GIS, identify the microbial species within these regionally specific mats, isolate and culture cyanobacteria from these mats and explore the applicability of using these organisms for treatment of industrial wastewater.

Microbial mat samples were collected from three geographical areas around Qatar, namely Ras Abrouq, Al Zubara and Khor Al Adaid. The collected microbial mats were firstly enriched in cultured medium. Different strains of cyanobacteria were isolated from these enriched mats and were cultured using solid media ASN-III and MN. Single strains of cyanobacteria were then sub cultured in BG-II liquid medium and were used to test the biodegradability of a test set of hydrocarbons (benzene, toluene and hexadecane). The optical densities of the cyanobacteria were measured using a spectrophotometer and the rate of biodegradation of the hydrocarbons were found using a Gas Chromatography Mass Spectrophotometer (GCMS).

Results show that most of the microbial mats identified in Qatar are found on the Dukhan coastline area. Another important area of mats is found at Khor Al Adaid (Inland Sea) located in the southeastern portion of the state. Different species of cyanobacteria were identified from these mats. The most common species identified from mats at Al Zubara were Oscillatoria, Phormidium, Microcolous, Lyngbya, and Spirulina. Those from Khor Al Adaid were Plectonema, Synechococcus, Phormeduim, Lyugbya, Oscillatoria, and Trichodesmium. Those from Ras Abrouq consisted mostly of Microcolous, Lyngbya, Pseudanabena, Oscillatoria, Phormidium, Spirulina, Gloeocapsa, and Aphanothecechroococcus.

Two species of the cyanobacteria, Oscillatoria and unicellular Cyanococcus, were successfully cultured and sub cultured in BG-II medium and used for biodegradation studies with hydrocarbons. Initial results suggest these species are capable of degrading hydrocarbons, but further studies are required to determine to what extent.

For future research, the duration of incubation of microbes with the chemicals of interest for degradation could be increased to help confirm capability. Furthermore, mixtures of different species of cyanobacteria could be used to understand if populations play a role in achieving effective biodegradation of hydrocarbons. This work is also being expanded to explore other microbes found around Qatar and testing their applicability to be effective “biodegraders”. All this research may be beneficial with our larger goal of finding more effective, efficient and environmentally natural approaches to treating industrial wastewater.

In the recent decades there has been an unprecedented globalization of trade. One of the most important factors that made this possible is the containerization of the supply chain. As a consequence container terminals have become essential for todays globalized economy. The trend of containerization has further extended to the cold supply chain through the use of reefers (refrigerated containers), resulting in a tremendous increase in the trade of food and other perishable goods. In case of import dependent countries like Qatar the cold supply chain has become essential for food security. The number of reefers at container terminals has substantially grown and as a consequence their energy use. In average ports, the largest part of energy is consumed by crane operations and cooling of reefers. In case of ports that are dedicated to export/import of foods the cooling of reefers becomes the largest component of terminal energy consumption. This is especially the case in countries with extreme temperatures like Qatar. Although there has been a substantial amount of research dedicated to optimizing operational procedures of cranes at container terminals with a focus on minimizing energy use, similar approaches have not been explored in case of reefers and the related cold supply chain. In this work we focused on the potential of exploiting a terminal truck appointment system (TAS) to this goal. The main objective of the TAS is to minimize the waiting times at the port gates and to maximize the utilization of container yard equipment. It is important to note that previous research has shown that the information from the TAS can be used to optimize the crane operations. The majority of the existing research on TAS systems has been dedicated to evaluating the potential benefits that such systems can bring to a port in the sense of truck turn times. The concept of including reefer related information into a TAS adds a new dimension to the problem. This is due to the fact that the energy use of a reefer container is directly related to its dwelling time. The idea is to minimize the stay of reefers at the port. To be more precise the objective is to minimize the time since a reefer is unloaded to the port until a truck takes it out of the port. In practice this means that we wish to get the trucks that import the reefers to come to the port as soon as possible. This type of work adds a new type of objective where there is a higher priority related to trucks importing reefers. It is possible to develop a mixed integer program to assist in designing optimal methods for TAS related issues it is often not the best choice. The problem is that due to the high level of unpredictability in the movement of trucks inside and outside of the port the evaluation of a TAS system in this way is often not adequate. Due to this fact, the evaluation of such systems is frequently done using discrete event simulations (DES). In the existing literature the schedule for trucks is fixed, and further analysis is done to evaluate the effect of missed appointments and the percentage of «walk-in» trucks. The DES is only used for the truck arrivals to the port and related use of resources (Entrance Gate, Yard, Exit Gate, etc.). In the proposed research we extend the DES to also include dynamic appointment scheduling. To be more precise, we analyze how requests arrive and how appointments are given. This is important in the context of reefers since we want to give then higher priority, in the sense of leaving appointment slots open for truckers that transport them out of the port, which would otherwise be booked. The proposed DES is used to evaluate several strategies for appointments systems for both minimizing turn times of trucks and the dwelling times of containers. We show that some strategies can notably decrease the energy used for reefer cooling while maintaining short truck turn times.

Fischer Tropsch Synthesis (FTS) is an exothermic chemical reaction in which synthesis gas (or ‘syngas’- a mixture of H2 and CO) is converted into hydrocarbons or value-added chemicals. In this process, a catalyst (typically cobalt based or Iron based) is used in a Fixed Bed (FB) or Slurry Bed (SB) reactor for the conversion process. Qatar hosts both the technologies in its world's largest Gas to Liquid (GTL) facilities (Shell Pearl GTL and Sasol Oryx GTL). Although both the technologies have been commercially implemented in a large scale, further process intensification by radial scale-up has been a challenging task due to certain process limitation associated with transport characteristics of both the beds. In particular, the FB technology has issues related to hotspot formation owing to exothermicity of the FTS process which is significantly better in its SB counterpart. Our efforts in the current study are invested to understand the FB performance when it is radially scaled-up to a higher reactor geometry, and to possibly mitigate the effect of hotspot formation. In particular, the objective of this work is to utilize the merits of nonconventional Supercritical Fluids FTS (SCF-FTS) to consolidate the benefits of both the beds (FB and SB) to address the challenges related to hotspot formation. For this, we have developed a multi-dimensional computational fluid dynamics (CFD) model in COMSOL® to facilitate a high-resolution understanding of both the SCF-FTS and conventional Gas Phase (GP)-FTS from the perspective of bed thermal management. As an extension to our previous modeling efforts in development of 1-D and 2-D FB-FTS model [1-2], we are currently involved in development of a multiscale 2D model to investigate the pore characteristics using both the modes of operation. Comprehensive experimental investigations were carried out at different operating conditions to support the modeling efforts. A conventional cobalt catalyst with inferior thermal conductivity was investigated in both GP-FTS and SCF-FTS. Later, a novel Micro-fibrous Entrapped Cobalt Catalyst (MFECC) with superior thermal conductivity was investigated in both GP-FTS and SCF-FTS. Conventional catalyst operated SCF-FTS conditions gave a very high value (0.90) than its GP-FTS. The MFECC catalytic bed on the other hand when operated in SCF-FTS conditions gave a slightly lower value (0.86), but six-fold % CO conversion than in GP-FTS. MFECC catalytic bed also exhibited higher C5+ selectivity & higher catalyst activity in SCF-FTS. In order to closely understand the intricate difference in thermal performance shown by the MFECC bed compared to conventional FB, we have performed a detailed CFD calculation. Results of the MFECC bed have shown to provide orders of magnitude improvement in bed thermal conductivity and proved its capability to control hotspot formation. In particular, the results of conventional FB at 20 bar and at a gas hourly space velocity of 5000 1/h in a reactor tube of 0.59 inch ID shows hotspot formation of about at the centerline. On the other hand, the temperature rise in MFECC bed for same operating condition was only. Further, a very recent outcome of this work enabled us to investigate the potential of scaling-up the radial geometry of the MFECC reactor to a 4” ID reactor to improve its throughput while maintaining temperature homogeneity in the reactor bed [2]. The proposed study is a part of a broader project involving both experimental and modeling studies, and is performed at multiple stages to enable mitigation of challenges related to reactor scale up, and runaway hotspot formation in a fixed bed FT reaction. References [1] M.M. Ghouri et al., Computers & Chemical Eng. 2016, 91, 38-48 [2] M.S. Challiwala et al., AIChE Journal, (Under Review)

Advances in catalyst and electrolyte materials for hydrogen fuel cells are driving performance gains and cost reductions that are helping to bring hydrogen fuel-cell technology to market. Research on new materials is always a combination of synthesis and characterization, where characterization must eventually include incorporation of materials into an operating fuel cell. It is at this stage that research on leading-edge new materials often stalls, because conventional fuel-cell tests require relatively large amounts of material, e.g. several grams of a new catalyst and tens to hundreds of grams of ionomer, corresponding to many tens of square centimeters of membrane area, are required to run a comprehensive set of tests as is necessary to assure reproducibility and examine behavioral trends. These amounts of material are often not available in early-stage synthetic work, which means that characterization uses other approximate approaches, e.g. rotating disk electrode (RDE) voltammetry to study catalyst activity, with true fuel-cell testing often being delayed until syntheses may be scaled up. This situation is unfortunate because approximate tests often do not adequately screen materials. It would be desirable to run preliminary fuel-cell tests at an early stage to gain a better idea of materials properties before making decisions regarding which materials to scale up. This contribution will present our recent work building and using a miniature PEM fuel-cell test fixture that uses only very small amounts of material to conduct a true solvent-free fuel-cell test. The cell is fabricated from a conventional compression-style fitting and uses 5/8 inch diameter graphite or metal rods for gas delivery and for making electric contact with the electrodes. Membrane-electrode assemblies (MEAs) are made from 3/4-inch diameter PEM disks, typically cut from Nafion ionomer membrane, onto which carbon-cloth-based electrodes are bonded by hot pressing. Electrode diameters range from 1/8 to 3/8 inch. The presentation will include recent published work demonstrating reproducibility and select MEA characterization data, including in-situ voltammetry to assess electrochemically active surface area (ECSA) of catalysts and polarization curve measurements that are easily obtained using conventional linear sweep voltammetry with a conventional laboratory potentiostat. This situation is in contrast to conventional fuel-cell testing that requires specialized instrumentation with passage of very large currents, e.g. tens of amperes. Very recent work using the cells in hydrogen pump configuration will also be presented. This configuration is particularly useful for measuring resistances to proton transport through ionomers in the direction through the membrane plane, in contrast to most measurements which focus on in-plane resistance, because it is easier to measure. Very recent work on the synthesis and properties of new tetra-aryl-phosphonium (TAP) alkaline ionomers which are expected have high alkaline stability and to be good hydroxide-ion conductors, and on the effect of single graphene layers embedded in Nafion membranes on proton and other ion conduction through the Nafion membranes, will also be presented.