Novel LiAlO2 Material for Scalable and Facile Lithium Recovery Using Electrochemical Ion Pumping

In this study, α-LiAlO2 was investigated for the first time as a Li-capturing positive electrode material to recover Li from aqueous Li resources. The material was synthesized using hydrothermal synthesis and air annealing, which is a low-cost and low-energy fabrication process. The physical characterization showed that the material formed an α-LiAlO2 phase, and electrochemical activation revealed the presence of AlO2* as a Li deficient form that can intercalate Li+. The AlO2*/activated carbon electrode pair showed selective capture of Li+ ions when the concentrations were between 100 mM and 25 mM. In mono salt solution comprising 25 mM LiCl, the adsorption capacity was 8.25 mg g−1, and the energy consumption was 27.98 Wh mol Li−1. The system can also handle complex solutions such as first-pass seawater reverse osmosis brine, which has a slightly higher concentration of Li than seawater at 0.34 ppm. © 2023 by the authors.This study is made possible by Qatar National Research Fund (QNRF) under National Priorities Research Program (NPRP) grant (#NPRP12S-0227-190166) and Graduate Student Research Award (GSRA) grant (#GSRA8-L-2-0411-21011).Scopu

Investigating the relationship between model organic compounds and ultrafiltration membrane fouling

The aims of this study were to investigate the fouling mechanisms of model organic compounds (MOCs) on two ultrafiltration membranes [composite regenerated cellulose (YM100) and poly- ethersulfone (PES)] and the relationship between fouling and membrane characteristics, flux decline, and the streaming potential (SP). Two alginic acids (polymer and dimmer, AA), abietic acid (AbA), colominic acid (CA), and N-acetylneuraminic acid (NA) were selected as MOCs to test their membrane fouling potential through flux decline and SP. The fouling caused by the two AAs, which contained many polysaccharides, was the highest among MOCs, but this fouling was exter- nal (solute deposition on the membrane surface) and reversible as polysaccharides did not strongly adsorb onto the YM100 and PES membranes. CA also caused external fouling of the two membranes; however, AbA caused internal (solute adsorption on the pores wall of membrane) and irreversible fouling of the PES membrane. NA, which contained amino sugars, exhibited very low fouling of both membranes. The hydrophilic YM100 membrane experienced less fouling than the hydrophobic PES membrane with all MOCs. The measurement of the SP using a modified dead-end filtration cell was employed to evaluate the flux decline due to MOCs. © Desalination Publicationsclose

Integrated photoelectrochemical (PEC)-forward osmosis (FO) system for hydrogen production and fertigation application

This study proposes an integrated system that combines a photoelectrochemical (PEC) system and forward osmosis (FO) system in tandem operation to address water, energy, and food (WEF) scarcity. The system utilizes a combination of ammonium sulfite and ammonium sulfate solution to represent wet flue gas desulfurization products from the ammonia scrubbing process commonly used in oil and gas producing countries. Under simulated sunlight, the sulfurous solution in the PEC system is oxidized at a reduced titania nanotube array (TNA) working electrode to produce hydrogen, a clean energy source (Energy). The oxidized sulfurous solution entering the draw solution (DS) compartment of the FO unit was then diluted when the FO system operates against simulated brackish water as the feed solution (FS, Water). The DS effluent is recirculated to ensure continuous operation of both PEC and FO systems. At a certain point in time, the DS effluent is also used as a cultivation solution for basil plants, the growth is visually more favorable compared to those supplied with tap water (Food). A concentrated DS (0.8:0.2 ratio of (NH4)2SO3:(NH4)2SO4) showed excellent water desalination performance. It had a high water flux of 17 LMH with 11.8 % water recovery, highest salt rejection (98.6 % for Na+ and 98.3 for Cl−), and lowest reverse solute flux (RSF) (3.5 g‧m−2‧h−1 for SO42−, 5.25 g‧m−2‧h−1 for SO32−, 3.1 g‧m−2‧h−1 for NH4+) against 5 g‧L−1 NaCl FS for 5 h, with a cathodic current density of 0.15 A‧cm−2. Overall, this study demonstrates the successful implementation of a bench-scale integrated system that produces tangible outcomes for water, energy, and food.This study was made possible by financial support from the Qatar National Research Fund (QNRF) under National Priorities Research Grant (NPRP) grant (NPRP 9-052-2-020). Open Access funding was provided by the Qatar National Library (QNL). H.P. is grateful to the National Research Foundation of Korea (2018R1A6A1A03024962, 2019R1A2C2002602, and 2021K1A4A7A02102598).Scopu

Efficient fouling control using outer-selective hollow fiber thin-film composite membranes for osmotic membrane bioreactor applications

This paper investigates the efficiency of fouling mitigation methods using a novel outer selective hollow fiber thin-film composite forward osmosis (OSHF TFC FO) membrane for osmosis membrane bioreactor (OMBR) system treating municipal wastewater. Two home-made membrane modules having similar transport properties were used. Two operation regimes with three different fouling mitigation strategies were utilized to test the easiness of membrane for fouling cleaning. These two membrane modules demonstrated high performance with high initial water flux of 14.4 LMH and 14.1 LMH and slow increase rate of mixed liquor's salinity in the bioreactor using 30 g/L NaCl as draw solution. OMBR system showed high removals of total organic carbon and NH4 + -N (>98%). High fouling cleaning efficiency was achieved using OSHF TFC FO membrane with different fouling control methods. These results showed that this membrane is suitable for OMBR applications due to its high performance and its simplicity for fouling mitigation.This work was supported by the Qatar National Research Fund (QNRF) [ NPRP 9-052-2-020 ]; the National Research Foundation of Korea [ 2014K1A1A2041044 , 2018R1A6A1A03024962 and 2017M1A2A2043123 ] and Bhutan Trust Fund for Environmental Conservation (BTFEC) [Project Grant No. MB0167Y16 ]

Thin-film composite hollow fiber membranes incorporated with graphene oxide in polyethersulfone support layers for enhanced osmotic power density

This study focused on the development of pressure retarded osmosis (PRO) thin film composite (TFC) membranes for enhanced osmotic power using hollow fiber polyethersulfone (PES) support structure modified by incorporating hydrophilic graphene oxide (GO) nanosheets. The GO loadings in the hollow fiber substrates were varied to improve water flux performances without compromising the mechanical strength. GO embedded (?0.2 wt%) PES hollow fiber supports revealed noticeable improvements in pure water permeability, improved structural morphologies, as well as the hydrophilicity within the support layer, without deteriorating the mechanical properties. The GO (0.2 wt%)-incorporated TFC-PRO membrane appeared to have an initial PRO flux (without any applied pressure) of 43.74 L m?2 h?1, lower specific reverse salt flux of 0.04 g L?1 and structural parameter (S) of 522 ?m, significantly better than the control membrane. The maximum power density of 14.6 W m?2 was achieved at an operating pressure of 16.5 bar under the condition of DI water and 1 M NaCl as feed and draw solutions, respectively. The results obtained in this study indicate that modification of PRO hollow fiber support layer by incorporating nanoparticles such as GO nanosheet can be a useful tool to improve the PRO performance. - 2019 Elsevier B.V.This research was supported by a grant from the Australian Research Council (ARC) Future Fellowship ( FT140101208 ) and the Qatar National Research Fund under its National Priorities Research Program award number NPRP 10-1231-160069 . The statements made herein are solely the responsibility of the authors and do not necessarily represent the official views of the Qatar National Research Fund. Appendix AScopu

High-Efficiency Solar Desalination Accompanying Electrocatalytic Conversions of Desalted Chloride and Captured Carbon Dioxide

The sustainability of conventional water- and energy-associated systems is being examined in terms of water-energy nexus. This study presents a high-efficiency, off-grid solar desalination system for saline water (salinities 10 and 36 g L-1) that accompanies electrocatalytic oxidations of chloride and, consequently, urine via oxidized chlorine species while concomitantly producing formate from captured CO2. A variable number of desalination cell arrays is placed between a double-layered nanoparticulate titania electrocatalyst (Ti/IrxTa1-xOy/nano-TiO2; denoted as n-TEC) anode and a porous dendrite Bi cathode. A potential bias to the n-TEC and Bi pairs initiates the transport of chloride and sodium ions in the saline water to the anode and cathode cells, respectively, at an ion transport efficiency of ?100% and a specific energy consumption of ?1.9 kWh m-3. During the desalination, the n-TEC anode catalyzes the conversion of the transported chloride into reactive chlorine species, which, in turn, mediate the decomposition of urine in the anode cell. Concurrent with the anodic process, formate is continuously produced at a faradic efficiency of >95% from the CO2 captured in the catholyte. When a photovoltaic cell (power conversion efficiency of ?18%) is coupled to the stack device with five desalination cells, the three independent processes synergistically proceed at a maximum overall solar-to-desalination system efficiency of ?16% and a maximum solar-to-formate chemical energy conversion efficiency of ?7%. - 2019 American Chemical Society.The authors are grateful to the Korea CCS R&D Center (KCRC) (no. 2014M1A8A1049354) for financial support. This research was partly supported by the National Research Foundation of Korea (2019R1A2C2002602, 2018R1A6A1A03024962, and 2019M1A2A2065616). S.Y.Y. is grateful to the NRF (2017R1C1B1005179). Y.P. is grateful to the Next-Generation Carbon Upcycling Project (2017M1A2A2043123). This publication was made possible by a grant from the Qatar National Research Fund under its National Priorities Research Program (NPRP 10-1210-160019).Scopu

A review of membrane-based dewatering technology for the concentration of liquid foods

The imperative to establish environmentally friendly and sustainable food processing techniques has compelled the food industry to explore alternative approaches that uphold food quality, ensure nutritional integrity, and minimize energy consumption. Extensive research conducted in the past decade has substantiated the superiority of membrane-based dewatering technology over conventional methods, owing to its ability to retain nutrients effectively while minimizing energy requirements. Notably, forward osmosis (FO) and membrane distillation (MD) have emerged as viable membrane technologies for food processing in the industry. However, recent reviews have underscored the prominence of FO in the enrichment of liquid food, positioning it as a preferred choice among other membrane-based processes. This review paper aims to elucidate the advancements and contributions of FO and MD in the realm of food processing while evaluating their maturity and technology readiness level for food concentration. Moreover, it endeavors to delineate specific parameters, including pretreatment techniques, membrane cleaning strategies, and membrane configurations/modules tailored to liquid food sources' distinct dewatering requirements. Although most FO and MD studies have focused on lab-scale fruit juice and whey concentration, future investigations should encompass pilot-scale process development alongside comprehensive techno-economic analyses to facilitate the smooth transition of these technologies to an industrial scale.This publication was made possible by UREP grant# [UREP 28-059-2-023] from the National Research Fund. Open Access funding was provided by the Qatar National Library (QNL). H.P. is grateful to the National Research Foundation for financial support (2019R1A2C2002602 and 2018R1A6A1A03024962).Scopu