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In this work we report the synthesis of copper oxide nanoparticles using solution combustion synthesis. These nanopowders are used as catalyst in ethanol decomposition reaction for hydrogen production. In situ study of ethanol decomposition has been conducted in FTIR using DRIFTS reactor at temperature of 50°C and 400°C over the reduced catalyst obtained after passing H2 at 300°C for one hour. XRD, SEM and TEM analysis were conducted to identify the phase and morphology of catalyst before and after reaction. Qatar Foundation;Qatar National Research Fund;Qatar University Scopus

This paper reports the thermodynamic analysis of the production of solar syngas (a mixture of H2 and CO with molar ratio equal to 2: 1) via ZnO/Zn based thermochemical H2O and/or CO2 splitting redox reactions. Solar syngas production from CO2 and H2O that is considered in a two-step thermochemical cycle via Zn/ZnO redox reactions, encompassing: 1) the ZnO thermolysis to Zn and O2 using concentrated solar radiation as the source of process heat, and 2) Zn reacting with mixtures of H2O and CO2 yielding high-quality syngas and ZnO. The ZnO is recycled to the first, solar step. Syngas is further processed to liquid hydrocarbon fuels via FischereTropsch or other catalytic processes. Second-law thermodynamic analysis is applied to determine the cycle efficiencies attainable with and without heat recuperation for varying the thermal reduction temperature (TR) in the range 1700-1950 K. Furthermore, the effect of various TR on molar flow rate of inert Ar has been presented. Considered is the energy penalty of using Ar dilution in the solar step below 2235 K for shifting the equilibrium to favor Zn production. Thermodynamic analysis has been performed and the analysis shows that solar syngas production via the Zinc Oxide redox cycle is a promising approach for CO2/H2O conversion into alternative fuels. Qatar University Scopus

This study assesses the potential use of mixed Indigenous Microalgae (MIMA) for carbon capture from flue gases in a photo-bioreactor. The effect of inlet CO2 concentration on the carbon biofixation rate was investigated. The PBR wasoperated under ambient conditions of solar irradiation and temperature for 3-months. Under the conditions studied, MIMA showed a significant carbon bio-fixation rates in order of 0.34 gC.L?1.d?1 suggesting that Microalgae with fast growth rate and naturally grown in the water system can be a sustainable and effective technology for CO2 uptake. Copyright (2018) by AIChE. All Rights Reserved. Scopus

This study evaluated the use of green algae Spirulina microalgae as a C02 capturing technology at different temperatures. The growth of Spirulina at 25 and 30◦C were studied in synthetic wastewater and its performance in removing nutrient were determined. Significant differences between the growth patterns of Spirulina were observed at different C02 dosage rate and different operational temperature. Spirulina showed the highest growth at 30 C and with a C02 injection dosage of 10%. Limited growth was observed for the systems injected with 5 and 15 % of C02 with respect to blank solution. Ammonia and phosphorus removals for Spirulina were 69%, 75%, and 83%, and 20%, 45% and 75 % for the media injected with 0, 5 and 10% C02. The results of this study show that simple and cost-effective microalgae-based wastewater treatment systems can be successfully employed at different temperatures as a successful C02 capturing technology even with the small probability of inhibition at high temperatures. Scopus

This paper reports the investigation of effect of temperature on physico-chemical properties of formulated solvent (comprises on ethylaminoethanol, N-methyl-2-pyrollidone, and K2CO3/KHCO3) and reaction kinetics of the absorption of CO2 in this formulated solvent. The physico-chemical properties were estimated by using a specific gravity bottle (density), an Ostwald's capillary viscometer (viscosity), and a stirred cell reactor (diffusivity and solubility of CO2 in formulated solvent). Similarly, a stirred cell reactor was used for the investigation of CO2 absorption kinetics by following a novel fall in CO2 pressure technique. Qatar University Scopus

In this paper, the solar thermochemical copper oxide - copper sulfate (CO-CS) water splitting cycle is thermodynamically investigated. CO-CS cycle consists of two steps: first step - exothermic oxidation of CuO via water splitting reaction producing H2, and second step - the CuSO4 is thermally decomposed into CuO, SO2, and O2. The CuO is recylced back to first step and can be used in multiple steps. This study is divided into two steps: 1. Thermodynamic equlibrium analysis, and 2. Second law energy and exergy analysis. At the end, the efficiency of CO-CS cycle is calculated and the results of the thermodynamic analysis are reported in detail. This publication was made possible by the NPRP grant (NPRP8-370-2-154) and UREP grant (UREP18-146-2-060) from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of author(s). The authors also gratefully acknowledge the financial support provided by the Qatar University Internal Grant QUUG-CENG-CHE-14/15-10. Scopus

The potential use of mixed indigenous microalgae (MIMA) as a CO2 capturing technology and treatment process for wastewaters was evaluated at two temperatures ( 25 and 30 C) and different CO2 dosage ( 0%, 5% and 15%). During the study the growth rate of MIMA, CO2 utilization capacity, removals of organic matter and nutrients from synthetic wastewater were followed. A noticeable difference between the growth patterns of MIMA was observed at different CO2 and different operational temperatures. MIMA showed the highest growth grate when injected with CO2 dosage of 5% compared to blank solution 0% CO2 injection. Ammonia removals for MIMA were 94%, 93%, and 84% for the media injected with 0, 5 and 10% CO2 at 25 C. The results of this study show that simple and cost-effective microalgae-based wastewater treatment systems can be successfully employed at different temperatures as a successful CO2 capturing technology. Scopus

This study reports the thermodynamic analysis of the cobalt oxide - cobalt sulfate (CoO - CoS) based water splitting cycle. CoO-CoS cycle consists of two steps: first step - exothermic oxidation of CoO via water splitting reaction producing H2, and second step - the CoSO4 is thermally decomposed into CoO, SO2, and O2. The CoO is recycled back to first step and can be used in multiple steps. This study is divided into two steps: 1. Thermodynamic equilibrium analysis, and 2. Second law energy and exergy analysis. At the end, the efficiency of CoO-CoS cycle is calculated and the results of the thermodynamic analysis are reported in detail. Qatar Foundation;Qatar National Research Fund Scopus

The present work shows a quick, simple and accurate method for algae harvesting with a potential to relate the required polymer dose with in-situ hydrodynamics properties of alga solution. The method also reduces the lag time between the change in influent quality and chemical dosing adjustment during dewatering process. The tests were carried out using single and multi stage conditioning steps. Spectrophotometric measurements can potentially be used to select the best performing polymer and determine the optimum polymer dose for any type of Algae; optimum polymer dose calculated by use of CST and volume of filtrate match with optimum polymer dose achieved with absorbance measurements. Multi-stage conditioning process using ferric chloride and polymer resulted in better settling and algae dewatering when compared to the single stage conditioning using polymer or ferric chloride alone. The amount of conditioner used in multi-stage conditioning processes was less than the doses required for single stage process. The presented method could be useful in monitoring and optimize the polymer concentration and minimize the excessive use of polymers. Copyright (2018) by AIChE. All Rights Reserved. Scopus

Current desalination techniques are typically very energy intensive: energy consumption can account for up to 70% of the desalination costs. To improve economics of water desalination plants innovative energy efficient, inexpensive, water pump powered by heat is proposed. The technology is an alternative to the reverse osmosis water desalination processes. It eliminates electricity consumption and the high-pressure pumps and permits improvements in the energy recovery. Instead of the use of positive displacement (plunger) pumps the pumped fluids (water) are compressed directly by heat in the heat driven pumps (or compressors) and the energy of the working fluid is directly transmitted to a liquid to be pumped. The pump can be powered by any source of heat, e.g. solar, geothermal, waste, combustion. A substantial improvement of the economics of the reverse osmosis processes is expected due to the use of renewable energy, considerable decrease of capital cost, increased energy conversion efficiency and reduced maintenance cost. Scopus

In this paper, the sol-gel synthesis of Mg-doped Niferrite i.e. Ni-Mg-ferrite was attempted by using propylene oxide (PO) as a proton scvanger. Effects of two important synthesis paramaters such as amount of PO added during synthesis and aging time on phyico-chemical properties such as phase composition, specific surface area (SSA), crystallite size, and particle morphology were studied by using different analytical methods such as powder X-ray diffractometer (PXRD), BET specific surface area analyzer, and scannning electron microscope (SEM). This publication was made possible by the NPRP grant (NPRP8-370-2-154) and UREP grant (UREP 18-146-2-060) from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of author(s). The authors also gratefully acknowledge the financial support provided by the Qatar University Internal Grant QUUG-CENG-CHE-14\15-10. Scopus

The degradations of volatile organic sulfur compounds (VOSCs) by advanced oxidation technology, solar advanced oxidation technology, biological treatment, and the combination of solar advanced oxidation technology and biological treatment were studied in a pilot plant. Three volatile organic sulfur compounds (Methanthiol (MESH), Dimethyl sulfifde (Me2S) and H2S) were selected as model compounds. Solar advanced oxidation technologies (AOTs) processes eliminate more than 65% of VOSCs under high residence time. VOSCs were oxidized to a very low level ≤ 0.2 μg/L in less than 60 min by solar-AOTs and ozone. A significant VOSCs elimination was achieved by solar advanced oxidation in combination with biological treatment. Removal efficiencies up to 95.7 % and 94.7 % of MSH and Me2S were achieved by combined processes at very low HRT for bioprocess (0.5 day). The results obtained from the combined processes (Solar-AOTs & bioprocess) confirm the suitability of solar AOTs as pre-treatment for VOSCs. Copyright © American Institute of Chemical Engineers. All rights reserved. Scopus