SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Zhaohao Li,Run Qi,Zheng Zhang,Heng Zhang,Haiping Chen,Dan Gao
Condensation is the common mechanism of water intake from gases. Transport membrane condenser is a newly proposed technology to recover water from flue gas based on the mechanism of condensation. Most of the existing heat transfer research on transport membrane condenser focuses on water vapor phase change or fluid convection heat transfer, and there is a lack of research on the thermal conductivity of ceramic membranes. The significance of studying thermal conductivity is to optimize the overall heat transfer performance. The thermal conductivity of alumina ceramic solid materials is not good enough, which can affect the industrial application performance to a certain extent. There is currently a lack of experimental measurements or theoretical calculations to quantitatively characterize the thermal conductivity of ceramic membranes. This affects the optimization of overall heat transfer performance of transport membrane condenser. In this paper, coal fly ash is used as the raw materials to prepare macroporous ceramic membranes. Coal fly ash is a very cheap material. It can greatly reduce the manufacturing cost of transport membrane condenser using coal fly ash to prepare ceramic membranes. The classical theoretical model of thermal conductivity of porous materials is introduced, the calculation and experimental results are compared, and the validity and limitation of the classical models in analyzing the heat transfer problem of transport membrane condenser are discussed. Finally, based on the composite effective medium theory, combining with the experimental results, a modified model is proposed. The modified model reduces the average theoretical error to 7.20%, and enriches the research on the heat transfer theory of transport membrane condenser.
研究领域:
材料科学
·
热力学
·
环境工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2023
·
IF 3.9
Jiguang Huang,Haiping Chen,Jihao Yang,Ziwei Du,Heng Zhang,Zhaohao Li
Transport membrane condenser can efficiently recover water and heat from wet flue gas . Ceramic membrane is the heat and mass transfer medium in the process. However, the relationship between membrane property and the recovery performance is only partially reported based on current research state. This work focuses on the effects of permeability, material, and ceramic particle size of membrane on the water and heat recovery. Membranes were prepared from three different sizes of coal fly ash and an alumina powder. Water and heat recovery performances of the membranes are experimentally compared. Results indicate that increasing membrane permeability improves water and heat recovery because the resistance of heat and mass transfer is reduced. The alumina membrane performs 3–10% more water recovery than the coal fly ash-based membrane while thermal conductivity of the alumina membrane was 11.5 times that of the coal fly ash-based membrane. Increasing ceramic particle size shows two opposite effects on the water and heat recovery, promotion because of the permeability rising, and undermine because of the thermal conductivity reduction. Low-cost membranes with high permeability and high thermal conductivity are recommended in transport membrane condenser application.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Yamei Yang,Rui Du,Changrui Shi,Jiafei Zhao,Yongchen Song,Lunxiang Zhang,Zheng Ling
With the rapid development of agriculture, controlling phosphorus emissions is a pressing challenge for preventing water eutrophication . A graphite-promoted cyclopentane (CP) hydrate-based desalination was proposed to remove K 3 PO 4 from effluents. It was found via the in situ optical microscopy that the reaction temperature and the concentration of feeding K 3 PO 4 solution significantly affect the morphologies and amount of the as-produced CP hydrate crystals. The lower reaction temperature produces more crystals with irregular shapes, while fewer crystals formed in K 3 PO 4 solution with higher concentration. The reaction temperature, time and feeding concentration-dependent desalination and salt enrichment performances were studied. It was found that desalination efficiency linearly increases with the elevated reaction temperature ranging from − 2 °C to 3 °C; however, water recovery declines with temperature. The temperature-dependent water recovery is due to the strong driving force for hydrate formation at low temperatures. The time-dependent water recovery shows a three-stage feature, including exponential growth, linear increase, and stable stages, owing to the interaction between the driving force of supercooling and the increasing K 3 PO 4 concentration during the reaction processes. The desalination efficiency shows an inverted volcanic shape with the increased concentration of feeding K 3 PO 4 solution. The pre-melting effect plays a critical role in improving desalination efficiency at high K 3 PO 4 concentrations. A maximum desalination efficiency of 85.0% was reached for treating an artificial solution with salinity as high as 42452 mg/L. Both desalted water and concentrated phosphorus-containing solution can be recovered by this method, which is attractive for producing freshwater with potential for recovery of resources.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Guozhao Ji,Weijian Wang,Huihuang Chen,Siyuan Yang,Jing Sun,Weng Fu,Zhiqiang Huang,Bo Yang
Brine management is one of the global challenges nowadays. Herein, by taking advantage of capillary forces and low-grade heat (50 °C), we propose a novel ceramic membrane-promoted crystallization (MPC) process for brine management. The MPC process simplifies the traditional multiple energy-intensive steps and dispenses the use of expensive anticorrosive equipment via adopting three hierarchical layers (α-Al 2 O 3 substrate, γ-Al 2 O 3 interlayer, and SiO 2 top layer). The hydrophilic mesoporous SiO 2 top layer provides continuous driving force for brine solution transport from the inner shell of the membrane toward the outer surface, where heterogenous nucleation and secondary nucleation occur to form numerous long needle-like salt whiskers. The growth kinetics of salt whiskers accelerates with time as the formed salt whiskers provide extra evaporation area to intensify water evaporation. Template-directing molecules P123 significantly enhance the specific surface area, pore volume, pore size, and pore regularity of the SiO 2 top layer, thereby promoting both water recovery and salt production. The optimized membrane displays high water recovery (790.3 g m −2 ) and salt production (194.6 g m −2 ) for high-salinity brine (20 wt%). Moreover, the MPC process demonstrates high performance, mechanical stability and thermal durability during the long-term test. It is expected that the MPC process would provide an innovative zero-liquid discharge approach for the efficient and low-cost brine management.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS ES&T Water
·
2022
·
IF 0
Shuangling Xie,Jiale Du,Xuan Huang,Ailiang Gu,Shengqiong Fang,Riri Liu,Dong Zou,Jiuyang Lin,Ming Xie,Shuaifei Zhao,Wenyuan Ye
Membrane distillation (MD) has been widely used for resource recovery from high-salinity wastewater, due to its superior technical merits of high separation efficiency and potential integration of low-grade heat. Herein, a robust superhydrophobic PVDF membrane prepared by spray-coating of fluorinated silica nanoparticles was employed to treat highly saline dye wastewater by MD. Specifically, impacts of operation conditions, including temperature difference, feed flow-rate, salinity, dye concentration, and dye species, on MD performance of the fabricated superhydrophobic PVDF membrane were comprehensively investigated. The increase of temperature difference and feed flow-rate had a positive effect on the MD flux of the membrane. Conversely, the rise in salinity and dye concentration induced an adverse impact on the MD flux. Furthermore, the superhydrophobic PVDF membrane showed a strong robustness in treating complex streams, as demonstrated by consistently stable MD flux using various dye/NaCl mixed solutions. Due to the robust surface superhydrophobicity, the fabricated PVDF membrane exhibited impressive antiwetting and antifouling properties against highly saline dye wastewater, consistently stable permeation flux, and high dye/salt removal efficiency (>99.99%). Moreover, the superhydrophobic membrane showed a high water recovery (90%) from highly saline dye wastewater with a slight reduction (13.4%) in permeation flux during a 39 h MD filtration. These results signify the promising practicability of the fabricated superhydrophobic PVDF membrane in sustainable management of highly saline dye wastewater via MD.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
Water
·
2023
·Vol. 15
·期 3
·439
·
IF 3.4
Yuting Wang,Haoquan Zhang,Ruixue Zhao,Die Wang,Lu Zhou,Le Han
Shale gas wastewater is a hypersaline industrial effluent in demand of efficient treatment or resource recovery. Membrane distillation (MD) is a heat-driven desalination process of high potential to deal with such streams. However, its application is highly limited by the unsatisfactory hydrophobic membranes that involve a trade-off between vapor permeability and fouling/wetting resistance. Our previous studies highlighted the potential role of an intermediate coating layer of a carbon nanotube (CNT) for the superhydrophobic membrane with 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS) grafted to address the trade-off issue against synthetic saline oily wastewater. The work herein investigated its application performance in the continuous concentration and water recovery of real shale gas wastewater, with a commercial PVDF membrane as the reference. The modified membrane recycled 48.2% of the total volume as high-quality water and rejected 99% of feed salinity, achieving a superior concentration rate and flux recovery rate compared to PVDF. The value of the COD, total nitrogen, and ammonia nitrogen in the permeate after the modified membrane was less than 50, 20, and 20 mg/L, meeting the local wastewater discharge standard. It was pointed out that the inorganic fouling for the MD membrane was more of a concern in dealing with a real stream, but the modified membrane exhibited excellent fouling resistance. The cost associated with the treatment was estimated at USD 2.2/m3for a production capacity of 2000 m3/d. The proposed superhydrophobic membrane has proven to be a feasible alternative from both technical and economic standpoints, offering the potential to improve MD effluent water quality and mitigate membrane fouling.Keywords:membrane distillation;shale gas wastewater;carbon nanotube;water recovery;membrane fouling
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Xinmiao Xu,Zhenjun Zhang,Xiulan Weng,Zuliang Chen
Extracting rare earth elements (REEs) from wastewater is crucial for saving the environment, sustainable use of natural resources and economic growth. Reported here is a simple, low cost and one-step synthesis of Fe nanoparticles (FeNPs) based on two plant extracts having the ability to recover REEs. The synthesis of FeNPs using Excoecaria cochinchinensis leaves extract (Ec-FeNPs) exhibited high selectivity for heavy rare earth due to unique biomolecules, achieving separation coefficients (K d ) of 3.16 × 10 3 –4.04 × 10 6 mL/g and recovery efficiencies ranging from 71.7 to 100 %. Conversely, the synthesis of FeNPs using Pinus massoniana lamb extract (PML-FeNPs) revealed poorer REE recovery efficiencies of 7.2–86.7 %. To understand the differences between Ec-FeNPs and PML-FeNPs in terms of selectivity and efficiency, LC-QTOF-MS served to analyze the biomolecules differences of two plant extracts. In addition, various types of characterization were carried out to identify the different functional groups encapsulated on the surface of FeNPs. These results reveal the source of the difference in the selectivity of Ec-FeNPs and PML-FeNPs for REEs. Furthermore, during DFT calculations, it was found that biomolecules with varying affinities for the surface of FeNPs interact with each other, leading to the formation of structures that exhibit high reactivity towards REEs. Finally, incorporating Spearman correlation analysis demonstrates that the selective removal efficiency of REEs was closely linked to surface complexation, ion exchange, and electrostatic adsorption. Consequently, this work strongly highlights the potential for the practical application of novel adsorbents in this field.
研究领域:
环境科学
·
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Chenxin Zhang,Wei Chen,Gary Owens,Zuliang Chen
There is increasing demand and interest in efficient methods for the recovery of rare earth elements (REEs) from wastewater because of the growing concerns associated with the negative impacts of REEs-rich waste discharged on pristine ecosystems. Here, we designed a ZIF-8@ALG composite hydrogel by encapsulating zeolitic imidazolate frameworks-8 (ZIF-8) into sodium alginate and poly (vinyl alcohol) double cross-linked networks (ALG) for the recovery of REEs from mine wastewater. ZIF-8@ALG showed exceptional REEs adsorption performance with the most superior separation factor (Ho/Mn) of 597.5. For the REEs considered, the ZIF-8@ALG composite exhibited a preference for heavy REEs with high adsorption efficiencies (65.3 ∼ 97.2%) and distribution coefficients (2045.5 ∼ 28500.0 mL·g −1 ). Adsorption involved a combination of electrostatic attraction, complexation and ion exchange mechanisms. REEs adsorbed on ZIF-8@ALG could also be desorbed using sodium citrate via ion-exchange and complexation, thus achieving efficient REEs recovery. In addition, ZIF-8@ALG was stable and reusable, maintaining effective adsorption in wastewater over four consecutive cycles, where the optimal adsorption efficiency reached 80.0%. Overall, this study provided an effective and feasible method for the recovery of REEs in mine wastewater, and confirmed that ZIF-8-based materials have significant potential for REEs recovery applications in wastewater engineering treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DESALINATION
·
2021
·
IF 9.501
Guozhao Ji,Weijian Wang,Huihuang Chen,Siyuan Yang,Jing Sun,Weng Fu,Bo Yang,Zhiqiang Huang
Potassium chloride (KCl) is a vital fertilizer to boost the global crop yield. However, current technologies for KCl production suffer from high energy consumption and complicated operations. Herein, we demonstrate a novel membrane-promoted crystallization (MPC) process for the sustainable production of KCl from concentrated KCl brine, together with water recovery . The MPC process reduces the capital expenditure and simplifies the complex operations by taking advantage of low-grade heat and a tubular hierarchical membrane (macroporous α -Al 2 O 3 substrate, γ -Al 2 O 3 interlayer and mesoporous hydrophilic ZrO 2 top layer). The presence of template-directing molecules P123 is vital in obtaining the mesoporous structure of ZrO 2 top layer by acting as a scaffold during the sol-gel process and preventing the meso-structural shrinkage in the annealing stage. The hierarchical membrane provides capillary forces to drive KCl brine transport from the inner shell of the membrane towards the outer surface. The continuous supply of KCl brine and water evaporation result in heterogenous nucleation and subsequent KCl crystal growth via a tip-growth mechanism, leading to abundant needle-shaped KCl whiskers on the outer surface based on the in-situ optical observation. The obtained KCl whiskers have a very small contact area with the membrane, thereby endowing facile KCl removal from the membrane surface to allow for the consecutive cycles. The MPC process exhibits a high KCl production of 134.3 g/m 2 and excellent water recovery of 738.7 g/m 2 for KCl brine (15 wt%) at 60 °C. Moreover, high performance and structural integrity of the membrane are retained after five cycles. The MPC process provides a new and promising approach for the sustainable production of KCl from KCl brine.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Yuan Luo,Miaoqu Wang,Lusi Wang,Jin Peng,Zhibo Zhang,Guangzhou Qu,Esmat F. Ali,Peter S. Hooda,Manlin Li,Jörg Rinklebe,Sabry M. Shaheen,Xiaohong Liu,Ronghua Li
MgO-based adsorbents have been extensively utilized for phosphorus (P) resource recovery from wastewater. However, the microscopic interfacial adsorption mechanisms of P on different MgO crystal facets remain insufficiently understood. Elucidating interfacial mechanisms is crucial for the directional regulation of optimized-performance MgO-based adsorbent development. Herein, three MgO materials, octahedral MgO (OC-MgO), cube MgO (CU-MgO) and hexagonal MgO (HE-MgO) were synthesized and tested for phosphorus (P) adsorption and recovery from water. OC-MgO primarily exposes the (111) facet, CU-MgO exhibits the (100) facet, whereas HE-MgO displays both the (111) and (110) facets, with exposure ratios of about 69.5 % and 30.5 %, respectively. Batch experiment results proved that P adsorption performance correlated with the exposed crystal surface. The saturated P uptake capacities are 403.44, 278.04, and 221.47 mg/g for OC-MgO, CU-MgO, and HE-MgO, respectively, at a solution pH of 7.0, as determined by Sips model fitting. However, CU-MgO shows a faster P capture rate a stronger resistance to pH interference than the other two MgOs. The combination of model fitting, Zeta potential analysis and X-ray photoelectron spectroscopy (XPS) characterization demonstrated that the P adsorptive mechanism involved synergistic monolayer and multilayer adsorption, driven by surface complexation, ligand exchange, and electrostatic attraction. In addition, the density functional theory (DFT) calculations further provided mechanistic insights into facet-dependent stability and adsorption behaviors. The MgO (100) facet can stably exist in aqueous solutions, and its primary P adsorption mechanism involves chemisorption driven by monodentate-mononuclear, bidentate-mononuclear and bidentate-binuclear complexation and lattice oxygen replacement. In contrast, the MgO (1 1 1) and (1 1 0) facets required hydroxylation to maintain structural stabilization in water. On these hydroxylated surfaces, their P capture mechanisms are predominantly governed by electrostatic attraction and –OH group replacement. This study elucidates the fundamental structure–property relationships between MgO crystal facets and P adsorption behavior, revealing facet-dependent stabilization mechanisms in aqueous environments and their associated P capture pathways. These findings provide novel perspective of surface design for developing MgO-based adsorbents for P capture and recovery from water.
研究领域:
环境科学
·
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING COMMUNICATIONS
·
2025
·
IF 2
Alvin H. H. Teo,S. Y. Chin,Fiona W. M. Ling,Hayder A. Abdulbari
Water shortage is an imminent issue in the foreseeable future while thermal desalination techniques are energy intensive. This study investigates a membrane-less low temperature technique known as directional solvent extraction (DSE) desalination in a serpentine microchannel at 45, 50, 55, 60 and 65 °C. Two lower fatty acids, heptanoic acid (HeptA) and nonanoic acid (NonA) were used as the solvents to recover water from a 35000 ppm total dissolved solids (TDS) seawater at 2, 3, 4 and 5 organic to aqueous flowrate ratios (O: aq). Custom-made polydimethylsiloxane (PDMS) – glass microfluidic device is fabricated via direct writing lithography with depth and length of 100 µm and 161 mm respectively while the width is varied from 400 - 800 µm. Droplets were generated during the extraction process to maximize diffusion by using a 90° T-junction where the organic solvent is the continuous phase and seawater is the dispersed phase. A maximum product water yield, Yw of 4 % v/v and 1.9 % v/v is achieved by HeptA and NonA respectively. The product water recovered from HeptA and NonA has salinity as low as 0.01% and 0.08%, respectively. The HeptA system produces water containing higher solvent residuals than the NonA system. HeptA is a better solvent as it can extract approximately two times more water than NonA under the same operating conditions. Both solvents are reusable.
研究领域:
环境科学
·
化学工程
·
水资源管理
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2020
·
IF 7.246
Hui Liu,Xiumin Li,Mengya Li,Yafei Zhang,Keyong Tang,Jie Liu,Xuejing Zheng,Ying Pei
The conventional beamhouse of leather making invariably results in serious pollution of sulfide, solid suspension and ammonia nitrogen because of the use of Na 2 S and Ca(OH) 2 in unhairing (liming) and reliming. It is an urgent issue to develop alternatives of the Na 2 S and Ca(OH) 2 system. In this work, the K + and Cl − of Hofmeister series are chosen to improve the binding ability of dispase to water molecules and substrate, which can further enhance the unhairing/fiber opening effect of dispase, with only one step for unhairing, opening collagen fiber-bundles and bating. The cycle unhairing effect of K + /Cl − /dispase solution system and its unhairing waste-water recycling in fiber opening are studied. The effect of K + and Cl − on the penetration of dispase in bovine hides, the hydrolysis for proteoglycans and elastic fibers, and the opening effect for collagen fiber-bundles are analyzed systematically. The results indicated that, the K + and Cl − increase the stability of dispase activity to 12 times of recycling for unhairing. Due to the electrostatic attraction of K + and Cl − to the charged amino acid residues, both the penetration of dispase in bovine hides and the hydrolysis of proteoglycans and elastic fibers are accelerated, and an easy step for unhairing/fiber opening is realized. Only 30 h is needed for unhairing/fiber opening, and the waste-water can be recycled for unhairing too. Because of the reuse of unhairing waste-water, low pollutant loads , high collagen fibril dispersity are reached. The resultant leathers are good in physical properties, and their thermal stability are comparable to that by the conventional process. The leather making system of KCl/dispase is suggested to be a cleaner and greener technology than the conventional ones.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）