Recovery Efficiency Research Articles

Optimization of extraction for efficient recovery of kenaf seed protein isolates: evaluation of physicochemical and techno-functional characteristics.

Kenaf seeds are a rich source of protein; however, finding the best extraction method is crucial to obtaining high-quality protein from these underutilized seeds. This research devised an optimized extraction process for best recovery of kenaf seeds protein using response surface methodology. The key parameters affecting the yield and protein content were optimized, including extraction pH (2-11), seed:water ratio (5:1-50:1), temperature (30-90 °C), and duration (20-360 min). The physicochemical and techno-functional properties of kenaf seed protein isolates (KSPIs) were examined. A maximum protein yield of 12.05 g/100 g with purity level 91.94 g/100 g was obtained using an optimized extraction with pH 11.0, seed:water ratio 50:1, 360 min duration, and temperature 50 °C. The oil and water retention capacities of KSPI were 1.14 mL g-1 and 1.37 mL g-1 respectively. After 30 min at pH 7, KSPIs demonstrated remarkable emulsion capacity (83.12%) and stability (75.63%), along with high foaming capacity (106%) and stability (18.3%). As per high-performance liquid chromatography analysis, arginine, glutamic acid, leucine, phenylalanine, and lysine were the most abundant amino acids detected in KPSIs. The KSPIs' globular protein structure was successfully verified using analytical approaches, including Fourier transform infrared spectroscopy, protein fraction ratios, and differential scanning calorimetry. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed that KPSI has a molecular weight distribution ranging from 10 kDa to 50 kDa. The results of this study support the application of the proposed response-surface-methodology-optimized extraction method for efficient recovery of high-quality kenaf seed proteins that meet the necessary physicochemical and techno-functional requirements. © 2024 Society of Chemical Industry.

Revolutionizing acridine synthesis: novel core-shell magnetic nanoparticles and Co-Zn zeolitic imidazolate framework with 1-aza-18-crown-6-ether-Ni catalysts

Nanoparticles have emerged as a critical catalyst substrate due to their exceptional features, such as catalytic efficiency, high stability, and easy recovery. In our research, we have developed an innovative and environmentally friendly magnetic mesoporous nanocatalyst. Using the co-precipitation method, we produced magnetic nanoparticles (Fe3O4) and coated them with Zeolitic imidazolate frameworks (ZIFs) to enhance their surface area and chemical stability. The resulting substrate was functionalized with 1-aza-18-crown-6-ether and nickel metal. Our prepared catalyst has been rigorously evaluated using advanced techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmet-Teller (BET), vibrating sample magnetometry (VSM), scanning electron microscopy and energy dispersive X-ray (SEM-EDS), inductively coupled plasma (ICP), elemental mapping analysis (EMA), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM). By synthesizing acridine derivatives, we have demonstrated the exceptional efficiency of our catalyst in organic compound synthesis. Through optimization, we have established the ideal parameters for catalytic processes, including catalyst amount, temperature, time, and ultrasonic use. Our catalyst has been proven to exhibit remarkable physical and chemical properties, such as porosity, temperature resistance, and recyclability. Notably, our heterogeneous nanocatalyst has shown outstanding performance and can be recycled six times without any loss in efficiency, affirming its potential in acridine.

Study and design of a Hydrogen liquefaction process using ethane as refrigerant fluid

Hydrogen liquefaction is an essential process in cryogenics, facilitating the efficient storage and transport of hydrogen as a clean energy carrier. This study investigates the liquefaction of hydrogen at a flow rate of 100 kmol/h, with an energy consumption of 447.05 kW. The process relies on sophisticated equipment, including multi-stage compressors and expansion devices, which play key roles in cooling and compressing the hydrogen gas. One of the notable advantages of this system is the energy recovery achieved by an expansion device, which generates 262.1 kW, enhancing overall efficiency.The hydrogen compression stages use a multi-stage compressor that employs water as the primary coolant. With a flow rate of 389.4 kmol/h, water is chosen due to its high specific heat capacity and availability, making it an ideal coolant for this cryogenic process. Ethane, serving as a secondary refrigerant, operates at a flow rate of 32 kmol/h. Its non-corrosive and inert properties contribute to system durability, while a portion of the ethane is strategically recycled through heat exchangers to minimize consumption and optimize cooling efficiency. Hydrogen enters the system at 5×10⁵ Pa and 288 K, and is gradually cooled and compressed to 2×10⁵ Pa and 22.75 K, resulting in the final liquid hydrogen product. This significant temperature reduction, achieved through the combined cooling effects of water and ethane, is critical for the successful liquefaction of hydrogen. The optimized use of refrigerants and efficient energy recovery in the expansion stages reduce operational costs and enhance process sustainability.

Textile Recycling: Efficient Polyester Recovery from Polycotton Blends Using the Heated High-Ethanol Alkaline Aqueous Process

Textile production has doubled in the last 20 years, but only 1% is recycled into new fibers. It is the third largest contributor to water pollution and land use, accounting for 10% of global carbon emissions and 20% of clean water pollution. A key challenge in textile recycling is blended yarns, such as polycotton blends, which consist of polyester and cotton. Chemical recycling offers a solution, in particular, alkali treatment, which hydrolyzes polyester (PET) into its components while preserving cotton fibers. However, conventional methods require high temperatures, long durations, or catalysts. Our study presents, for the first time, the heated high-ethanol alkaline aqueous (HHeAA) process that efficiently hydrolyzes PET from polycotton at lower temperatures and without a catalyst. A near-complete PET hydrolysis was achieved in 20 min at 90 °C, while similar results were obtained at 70 °C and 80 °C with longer reaction times. The process was successfully scaled at 90 °C for 20 min, and complete PET hydrolysis was achieved, with a significantly reduced liquid-to-solid ratio, from 40 to 7 (L per kg), signifying its potential to be implemented in an industrial context. Additionally, the cotton maintained most of its properties after the treatment. This method provides a more sustainable and efficient approach to polycotton recycling.

Efficient Ground-State Recovery of UV-Photoexcited p-Nitrophenol in Aqueous Solution by Direct and Multistep Pathways.

Nitroaromatic compounds are found in brown carbon aerosols emitted to the Earth's atmosphere by biomass burning, and are important organic chromophores for the absorption of solar radiation. Here, transient absorption spectroscopy spanning 100 fs-8 μs is used to explore the pH-dependent photochemical pathways for aqueous solutions of p-nitrophenol, chosen as a representative nitroaromatic compound. Broadband ultrafast UV-visible and infrared probes are used to characterize the excited states and intermediate species involved in the multistep photochemistry, and to determine their lifetimes under different pH conditions. The assignment of absorption bands, and the dynamical interpretation of our experimental measurements are supported by computational calculations. After 320 nm photoexcitation to the first bright state, which has 1ππ* character in the Franck-Condon region, and ultrafast (∼200 fs) structural relaxation in the adiabatic S1 state to a region with 1nπ* electronic character, the S1 p-nitrophenol population decays on a time scale of ∼12 ps. This decay involves competition between direct internal conversion to the S0 state (∼40%) and rapid intersystem crossing to the triplet manifold (∼60%). Population in the T1-state decays by excited-state proton transfer (ESPT) to the surrounding water and relaxation of the resulting triplet-state p-nitrophenolate anion to its S0 electronic ground state in ∼5 ns. Reprotonation of the S0-state p-nitrophenolate anion recovers p-nitrophenol in its electronic ground state. Overall recovery of the S0 state of aqueous p-nitrophenol via these competing pathways is close to 100% efficient. The experimental observations help to explain why nitroaromatic compounds such as p-nitrophenol resist photo-oxidative degradation in the environment.

Recovery of Xenotime and Florencite from Silicate Minerals Using a Combined Technique of Magnetic Separation and Flotation

Xenotime (YPO4), a significant phosphatic minerl rich in heavy rare earth elements (HREEs), typically associates with granitic rocks, exemplified in the Wolverine rare earth deposit in Australia. A mineral composition analysis indicates that the primary valuable minerals in the deposit are principally xenotime and minor florencite, with quartz and illite as the main gangue minerals, showing a relatively simple mineral composition. The grade of rare earth concentrate was increased to 14.29% and the recovery reached 94.48% through the magnetic separation pre-enrichment test. However, a high-grade rare earth concentrate could not be achieved using magnetic separation alone. Further purification of the magnetic concentrate is conducted through flotation. The grade of rare earth concentrate reached 51.26%, and the recovery rate reached 90.47%. In summary, this process achieves the efficient recovery of xenotime and florencite, having substantial industrial potential.

Recovery and partial isolation of ⍺-mangostin from mangosteen pericarpsvia sequential extraction and precipitation.

This study introduced an innovative sequential extraction methodology designed for the efficient recovery of alpha-mangostin (⍺-M) from mangosteen pericarps. Alpha-mangostin, renowned for its pharmacological properties including anti-inflammatory, anti-cancer, and anti-bacterial effects, has garnered significant attention across diverse industries. The proposed method of sequential extraction achieved 73% recovery and a yield of 46.75 mg/g based on the weight/weight percentage of the mass of ⍺-M extracted from the sequence and the mass of raw material. Furthermore, the purity of the dried product was 67.9%. The sequence solvent extraction system, comprising water, hexane, and acetonitrile, plays a pivotal role in enhancing the efficacy of the extraction process. Notably, this methodology offers a cost-effective alternative to conventional extraction methods. It reduces the need for complex equipment and processes, positioning it as a resource-efficient extraction technique in comparison to existing methodologies. This novel sequential extraction method presents a promising avenue for the economical and sustainable recovery of alpha-mangostin (⍺-M) from pericarps.

Arabic gum-grafted-polyaniline@MnFe2O4/UIO66-NH2 bionanocomposite as adsorbent for quercetin antioxidant: Efficiency, kinetics, thermodynamics and isotherm modelling

Quercetin is one of the most powerful antioxidants in nature and a major dietary flavonoid, so its efficient recovery by nanoadsorbents can be valuable for human health. In this study, the nanocomposite Arabic gum-grafted-polyaniline@MnFe2O4/UIO66-NH2 (AG-g-PANI@MnFe2O4/UIO66-NH2) was synthesized by in situ copolymerization. The physicochemical and structural properties of the AG-g-PANI@MnFe2O4/UIO66-NH2 nanocomposite were examined using various methods, including XRD, FE-SEM, FT-IR, EDX, VSM, TGA, and BET. The adsorption capacity of natural nanoadsorbent was evaluated for the adsorption of quercetin antioxidant from an ethanol-water solution (50 % v/v) in a batch system. The influence of controlling factors such as solution pH, adsorbent dose, contact time, initial quercetin concentration and temperature on the adsorption process was investigated. The highest adsorption capacity (9.1157 mg.g−1) was achieved at a pH of 8, with 0.025 g of adsorbent, a quercetin solution concentration of 20 mg.L−1, a 300 min contact time and at the temperature 298.15 K. In addition, the data from adsorption experiments were analyzed using different isotherm and kinetic models. The findings demonstrated that the Temkin isotherm and the pseudo-second-order kinetic model are the most suitable for representing the adsorption behavior. In addition, from analysis of the temperature effect was found that the adsorption of quercetin on AG-g-PANI@MnFe2O4/UIO66-NH2 is a spontaneous (∆G° < 0) and exothermic (ΔH° < 0) process. Finally, the reusability of nanoadsorbent and desorption kinetics of quercetin were investigated and it was specified that AG-g-PANI@MnFe2O4/UIO66-NH2 can be effectively renewed and recycled, maintaining its adsorption efficacy without significant reduction after five repeated cycles.

Performance of carbon felt as cathodes in magnesium corrosion method to recover phosphate from swine wastewater

With the large-scale development of the livestock and poultry breeding industries, swine wastewater with high nitrogen and phosphorus concentrations has become an urgent problem. Given the continuous demand for phosphorus resources in industrial production, the study of phosphate recovery in phosphorus-rich wastewater is of great value for the sustainable utilization of phosphorus resources and for alleviating the eutrophication of aquatic ecosystems. In this study, a magnesium metal corrosion method was used to recover phosphorus resources from swine wastewater using carbon felt as the cathode instead of traditional cathode materials such as graphite and titanium plates. The effects of different cathode materials on the corrosion potential of magnesium metal plates were compared, and the effects of carbon felt as a cathode plate on the removal rate and pH of phosphate from wastewater were discussed. Additionally, the economic feasibility of phosphate recovery from swine wastewater was evaluated. The experimental results showed that the effect of carbon felt on the corrosion potential of the magnesium metal plate was more evident than that of the graphite and titanium plates (Ecorr = −1.74676). When carbon felt was used as the cathode plate, the most energy-saving reaction conditions were as follows: reaction time T = 30 min, ratio of wastewater volume to plate area V: S = 500 cm3:50 cm2, aeration rate Re = 8 L/min, stirring rate r = 400 rpm, phosphate recovery rate = 92.3%, and pH = 8.83. The economic feasibility assessment shows that the proposed method is $2.047 g-1 PO4-P without considering the reuse of carbon felt. Carbon felt has good stability and can be recycled eight times or more, and the proposed method achieves a more efficient phosphate recovery rate at a relatively low cost.

Towards a high-rate operation of contact stabilization process: Challenges of flocculation and floc stability

The high-rate contact stabilization (HiCS) process, a variant of high-rate activated sludge, has gained attention for its superior energy recovery and enhanced biosorption capabilities. The need for efficient energy recovery in HiCS necessitates a high settling efficiency to minimize resource loss due to endogenous sludge consumption. However, the low sludge retention time (SRT) required for HiCS can significantly affect sludge floc stability and flocculation performance, warranting a deeper analysis of the factors influencing these characteristics. This study investigates the impact of SRT reduction on sludge performance, focusing on energy potential, viscoelasticity, and critical pressure. The analysis was conducted using rheological tests, contact angle measurements, zeta potential analysis, Fourier transform infrared spectroscopy, XDLVO theory, and the PARAFAC model. Results indicate that due to the contribution of hydrophobicity, the HiCS system maintained the large flocs morphology of the sludge even when the SRT was maintained for 2d. However, a combination of aerobic microbial activity, high concentrations of loosely bound extracellular polymeric substances, and the presence of the filamentous bacterium Thiothrix contributed to reduced flocculation performance.

A flexural-beam-type wide-frequency piezoelectric energy harvester for vertical shaft lifting system vibration monitoring

Abstract The coal mine lifting system may experience serious safety accidents due to severe problems with the bucket guides and rolling guide shoes. A piezoelectric energy harvesting (PEH) device for vibration sensor monitoring of shaft lifting system is proposed for the first time to monitor health of shaft lifting system. However, there are differences in the vibration frequencies, the working conditions are complex, leading to issues such as low energy recovery efficiency of the PEH and difficulty in achieving self-powered. To enhance PEH adaptability and reliability, a specifically designed flexural-beam-type wide-frequency piezoelectric energy harvester(FBT-WF-PEH) and a method of achieving real-time vibration monitoring through auxiliary power supply have been proposed. The results indicate when the excited frequency is 17Hz, the highest external output voltage is 11.2V, and under an external load of 17.5kΩ, the maximum output power is 7.168mW, demonstrating a good performance in terms of output power, and energy harvest bandwidth. The captive power supply test verified the PEH can utilize the vibration environment to achieve auxiliary power supply for monitoring systems under working conditions, which is of great significance for conducting research on health monitoring systems for lifting equipment. On the other hand, the new structure proposed in this study matches the operating frequency in the shaft lifting system, and the energy harvest efficiency is higher.

Self-sustained stable combustion of off-gas from Solid Oxide Fuel Cell in a cone-shaped porous burner with preheaters

A divergent porous medium burner with three embedded preheaters has been numerically studied in this paper. The burner can be used to recover heat from Solid Oxide Fuel Cell for burning extremely low calorific off-gas. The developed burner consists of a conical section filled with porous media in the upper part and three preheaters located downstream through which the fresh mixture recovers heat from exhaust gas. A coupled solution method is used to study the structure of the preheater, and the feasibility of the method is verified. The results show that the burner can use the heat recovered from the exhaust gas to burn mixtures without the need for any external heating. The burner is capable of dealing with extremely low calorific off-gas, it can stabilize the combustion of a mixture with a heating value of 0.908 MJ/kg. The results also show that the mass flow ratio has a great influence on the recovery efficiency. When the mass flow ratio is less than one, the recovery efficiency increases sharply with the increase of mass flow ratio. With the further increase of mass flow ratio, the recovery efficiency decreases. This study provides the guidance for the treatment of low-grade off-gas without additional energy consumption.

Selective recovery of Au from waste printed circuit board by water-soluble organic leaching: The key role of in situ bromine mediation and identificationof pathway

A large amount of gold in electronic waste (E-waste) is not properly recovered owing to the absence of efficient and safe leaching methods. Herein, we proposed the concept of ‘water-soluble organic Au leaching’ and created a new water-soluble organic leaching agent, WS NBS–DMF, by dissolving millimolar amounts of N-bromosuccinimide (NBS) and dimethylformamide (DMF) in water. Under mild conditions (25 ℃, pH 7.0), WS NBS–DMF achieved a 94.9 % leaching efficiency of Au for waste printed circuit board (WPCB) with limited leaching of base metals. The potent bromine radical (Br•) and ligands significantly contributed to Au complexation and oxidization via in situ bromine generation and radical initiation from WS NBS–DMF. The bidirectional hydrogen-bond effect of DMF facilitated the in situ bromine generation. Two Au(I) complexes ([AuBr2]- and [(NHS)AuBr]-) and an Au(III) complex ([(NHS)AuBr3]-) were confirmed as the Au leaching products by spectroscopy and mass spectrometry. Furthermore, reciprocal σ-donations between the Au center and ligands in the bonding orbitals enhanced the stability of the Au complexes, thereby promoting efficient Au leaching. Comparing with other leaching methods, this study of WS NBS–DMF provides a safe, economic and eco-friendly technique for efficient and selective gold recovery from e-waste.

Landfill leachate detoxification and decoloration for energy reclamation via microalgae-bacteria synergy

Upcycling of hidden energy and resources from landfill leachate (LL) into short-chains fatty acids (SCFAs) represents a substantially unexploited opportunity to handle environmental issue and achieve a circular economy. Due to high biotoxicity and poor biodegradability, efficient conversion of LL into SCFAs remains a great challenge. Herein, a hybrid electro-biosystem that coupling spatially separate LL electrochlorination, photo-remediation and dark fermentation was constructed to realize LL toxicity alleviation, resource recovery and SCFAs production in cascade. During LL electrochlorination, macromolecular organics evolution and LL toxicity alleviation mechanisms were revealed, in which available Cl- concentration played key role on LL properties amendment. During microalgae photo-remediation, resources recovery efficiency demonstrates that suitable LL electrochlorination can enhance microalgal photosynthesis and stimulate intracellular energy accumulation. Finally, SCFAs were produced from microalgae biomass via dark fermentation with butyric acid and acetic acid as major products, outputting total energy of 4.38 kJ/L. The work provides a paradigm shift of low-cost LL disposal with extra benefit of SCFAs production.

The Improved EMS Algorithm for Latent Variable Selection in M3PL Model

One of the main concerns in multidimensional item response theory (MIRT) is to detect the relationship between items and latent traits, which can be treated as a latent variable selection problem. An attractive method for latent variable selection in multidimensional 2-parameter logistic (M2PL) model is to minimize the observed Bayesian information criterion (BIC) by the expectation model selection (EMS) algorithm. The EMS algorithm extends the EM algorithm and allows the updates of the model (e.g., the loading structure in MIRT) in the iterations along with the parameters under the model. As an extension of the M2PL model, the multidimensional 3-parameter logistic (M3PL) model introduces an additional guessing parameter which makes the latent variable selection more challenging. In this paper, a well-designed EMS algorithm, named improved EMS (IEMS), is proposed to accurately and efficiently detect the underlying true loading structure in the M3PL model, which also works for the M2PL model. In simulation studies, we compare the IEMS algorithm with several state-of-art methods and the IEMS is of competitiveness in terms of model recovery, estimation precision, and computational efficiency. The IEMS algorithm is illustrated by its application to two real data sets.

Screening Tomato Genotypes for B–Recovery and Acquisition Potential in Calcareous Soils

ABSTRACT Screening a suitable genotype is important for nutrient recovery and its acquisition potential. Twenty genotypes of tomato were studied under different doses of B-application. The indices of B use efficiencies, viz. apparent B recovery (ABR), fruit production efficiency (FPE), physiological efficiency (PE), agro-physiological efficiency (APE) and utilization efficiency ratio (UER) were worked out for tomato genotypes. The field experiment was laid out in a split-plot design for the two consecutive years, assigning three B levels (control i.e. without B application, @ 2.0 kg B ha−1 through borax and 0.25% boric acid foliar spray twice) in main plot and location-specific twenty tomato genotypes in subplots, replicated thrice. Soil applied B produced greater fruit yield than the twice foliar spray of 0.25% boric acid B. However, the tomato fruit yield was improved by 2–12% over control by soil applied B @ 2.0 kg B ha−1 through borax and twice foliar spray of B. Irrespective of genotypes, B content in fruit and shoot of tomato plant improved upon application of B. The apparent B recovery (ABR) and agronomic efficiency (AE) of B suggested that foliar application was more effective in comparison to soil application. The use efficiencies were highest in the cultivars NS–812 followed by NS–512 and B–9–2 in B-deficient calcareous soils with the application of 0.25% boric acid foliar spray twice. These genotypes could be a promising lines for breeding program for B enrichment in tomato for cultivation in B-deficient soils.

Preparation of TA-O-MoS2/PES mixed matrix ultrafiltration membrane for rare earth wastewater treatment

The trade-off between permeability and selectivity, along with the issue of membrane fouling, has constrained the widespread application of ultrafiltration (UF) membranes in recycling rare earth wastewater. Here, we present the incorporation of tannic acid (TA) modified molybdenum disulfide oxide (O-MoS2) as a functional enhancer to fabricate polyethersulfone (PES) based mixed matrix membranes through a nonsolvent induced phase separation (NIPS) approach. Compared to the unmodified PES membrane, the integration of TA-O-MoS2 significantly improves the hydrophilicity, porosity in the mixed matrix membrane. By altering the concentration of TA-O-MoS2, the TA-O-MoS2/PES UF membrane achieves enhanced hydrophilicity and charge properties, resulting in a remarkable improvement in separation performance. Specifically, the optimized membrane M2 (TA-O-MoS2 addition of 0.1 wt%) exhibits a water flux of 140.98 Lm−2h−1bar−1 and a PEG 20000 rejection rate of 91.00 %, representing increases of 180 % and 120 % over the control PES membrane, respectively. Notably, membrane M2 effectively retains 91.31 % of macromolecular organic compounds in rare earth wastewater, while permitting nearly complete passage of inorganic salts, for instance CaCl2 (3.26 %) and MgSO4 (4.84 %). Moreover, the TA-O-MoS2/PES membrane demonstrates robust antifouling properties and exceptional durability, indicating its significant potential for efficient treatment and resource recovery in rare earth wastewater.

Ductile (Ag,Cu)2(S,Se,Te)-based auxetic metamaterials for sustainable thermoelectric power generation

Sustainable energy solution has resulted in significant interest in thermoelectric power generation, converting waste heat into electricity. However, the practical application of thermoelectric generators has been hindered by issues with their adaptability to arbitrary heat sources and durability in an operational environment. Here, we propose deformable auxetic thermoelectric metamaterials composed of high-entropy (Ag,Cu)2(S,Se,Te) ductile alloys, realized using finite element modelling and three-dimensional (3D) printing. We design a re-entrant auxetic structure with a negative Poisson’s ratio to maximize the mechanical deformability and develop an (Ag,Cu)2(S,Se,Te) particle-based colloidal 3D printable ink, tailored with Te microparticles. The 3D-printed (Ag,Cu)2(S,Se,Te) alloy exhibit a ZT value of 1.15 coupled with high compressive strength (208 MPa) and fracture strain (17.5 %). The fabricated auxetic metamaterials exhibit excellent vibrational stability and adaptability to diverse curved surfaces, realizing efficient power generation on a synclastic curved heat source. Our approach offers a method to design durable and efficient heat recovery devices.

Capacitive lithium capture system using a mixed LiMn2O4 and LiAlO2 material

The increasing demand for lithium (Li), a crucial material in various industries, requires efficient recovery methods and a shift toward a circular economy. This study investigates a fast, eco-friendly technique for selective Li recovery, emphasizing the use of innovative materials from spent Li-ion batteries (SLiBs), particularly LiMn2O4(LMO)/LiAlO2(LAO)-based materials, to enhance Li's circular economy. Conventional Li recovery methods typically involve prolonged processes with chemical additives and environmental concerns, whereas electrochemical systems like membrane-based capacitive deionization (MCDI) offer promising high removal capacities, regeneration ability, and scalability. However, no commercial electrochemical Li recovery system underscores the need for continued research to improve their performance. This study employs MCDI for selective Li recovery, examining various electrode materials, including commercial activated carbon, LMO-based electrodes, and modified LMO/LAO-based electrodes. The mixed LiMn2O4/LiAlO2 cathode exhibited high selectivity for Li+ extraction with a recovery efficiency of 83.1 %, achieving a deionization capacity of 38.15 mg/g at 1.0 V under an initial feed concentration of 5 mM LiCl. The Li+ adsorption reached 900 μmol/g, with a separation factor (αMg2+Li+) of 3.77 (CMg2+/CLi+ = 1), setting a robust foundation for a comprehensive Li recovery framework that meets the increasing Li demand while minimizing environmental impact.

Effect of Microgravity on Rare Earth Elements Recovery by Burkholderia cepacia and Aspergillus niger

Rare earth elements (REEs) are indispensable in modern industry and technology, driving an urgent demand for innovative, eco-friendly recovery technologies. As space exploration advances, the impact of microgravity on microorganisms has become a focal point, yet the effects on microbial growth and REEss recovery remain uncharted. This study investigates the biosorption of REEs by Burkholderia cepacia (B. cepacia) and Aspergillus niger (A. niger) from a mixed solution containing La, Ce, Pr, Nd, Sm, Er, and Y under varying initial concentrations, pH levels, and microgravity conditions. We observed that the medium’s pH rose with B. cepacia and fell with A. niger when cultured in normal gravity conditions, suggesting distinct metabolic responses. Notably, microgravity significantly altered microbial morphology and metabolite profiles, significantly enhancing REEs recovery efficiency. Specifically, the recovery of B. cepacia of Ce and Pr peaked at 100%, and A. niger achieved full recovery of all tested REEs at pH 1.5 (suboptimal growth conditions). This study pioneers the application of biosorption for the recovery of REEs in microgravity conditions, presenting a promising strategy for future resource exploitation by space biomining.