JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2023
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IF 8.7
Bo Lv,Xiaoman Chai,Xiaowei Deng,Feishuo Jiao,Chaojun Fang,Baolin Xing
Recovering inner residual carbon is important for fully utilizing coal gasification fine slag (CGFS) resources. In this study, we adopted a combined gravity-separation and flotation process to efficiently recover residual carbon by considering the characteristics of the CGFS and optimizing the operating factors of the process. CGFS is principally a mixture of residual carbon and ash, with low-density particles containing more of the former. Accordingly, residual carbon is preliminarily enriched by gravity separation, in which gas velocity ( v g ) and water velocity ( v w ) significantly impact separation efficiency, followed by feed volume ( m ). The residual carbon in the initial concentrate was preliminarily enriched (i.e., loss on ignition ( LOI ): 55.90%; combustible recovery ( R o ): 72.36%) under appropriate operating conditions (i.e., v w = 0.04 m/s, v g = 3 m/s, m = 150 g). Moreover, the quality of the flotation concentrate was most influenced by collector dosage ( m c ), followed by aeration rate ( η ), frother dosage ( m f ), stirring speed ( w ), and grinding time ( t ) during flotation of the primary concentrate. The flotation concentrate exhibited LOI and R o values of 90.95% and 50.34%, respectively, under the optimal flotation conditions (i.e., m c = 20 kg/t, m f = 15 kg/t, w = 2600 rad/min, η = 200 L/h, t = 360 s); it has a high residual carbon content and is an ideal raw material for preparing fuels or carbon materials.
研究领域:
矿物加工工程
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资源与环境科学
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DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
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IF 9.7
Changjin Guo,Yinghao Xu,Congcong Ni,Xiaofan Pan,Leonard D. Tijing,Ho Kyong Shon,Ning Deng,Xin Huang
Nitrogen and phosphorus recovery from wastewater to produce struvite fertilizer can simultaneously alleviate water eutrophication and phosphorus scarcity. Coupled magnesium mineral dissolution and reprecipitation has been emphasized for struvite formation by avoiding excessive Mg salts addition and pH adjustment. However, the recovery efficiency is limited by the low solubility of magnesium mineral. Herein, we capitalized on the concept of “pore-size controlled solubility (PCS)” to enhance the dissolution of MgAl-layered double oxide (MgAl-LDO), where dissolution rate is inversely related to pore size. By reducing the pore size of LDO X from 9.2 to 5.5 nm, the magnesium release from LDO X dissolution increased from 64.0 to 99.0 mg/L, accompanied by OH − release to maintain an alkaline condition. This resulted in effective recovery of NH 4 -N (80.54%) and PO 4 -P (80.57%) as high-purity struvite. Scanning electron microscope revealed that LDO acted as seeded surfaces that significantly reduced struvite nucleation barrier by controlling local supersaturation and interfacial energy. Moreover, the recovery is stable across wide pH ranges (5.0–10.0), attributable to the buffering capacity of Al in LDO X . Finally, the feasibility of NH 4 -N and PO 4 -P recovery was successfully applied to real aquaculture wastewater. This study offers an effective strategy to enhance mineral dissolution-precipitation for resource recovery.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2025
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IF 8.4
Teng Zhang,Jingmin Yan,Zhengchen Li,Hongyang Wang,Peiwei Han,Shufeng Ye
Red mud (RM) is a strongly alkaline solid waste produced during the production of alumina from bauxite. China's RM stockpile exceeds 1 billion tons, with an annual output of over 100 million tons. However, the comprehensive utilization percentage is less than 10%, and the rest are stored around alumina plants, which are severely burdening land and the surrounding environment. This study proposes a combined roasting process, which combines soda roasting with medium-temperature magnetization roasting, to synchronously convert minerals in RM into magnetite and soluble aluminate, to achieve the goals of iron concentrate upgrading and aluminum recovery. Iron concentrate with of yield of 72.52 wt%, total iron (TFe) concentration of 63.84 wt%, iron recovery of 93.47 wt%, and aluminum concentration of 2.53 wt%, and the aluminum product with the Al 2 O 3 concentration of 99.49 wt% were obtained under the optimized process parameters. Four pathways to iron concentrate upgrading that reduce the aluminum concentration during combined roasting are proposed based on the non-isothermal kinetic analysis and phase evolution results. These results can provide theoretical support for the comprehensive utilization of iron and aluminum in RM.
研究领域:
冶金工程
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环境科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
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IF 13.2
Zhengbin Li,Xiangfang Liu,Xianyu Kang,Qingchun Ge
The recycling of spent LiCoO 2 batteries generates acidic wastewater containing Li + and Co 2+ , typically treated using nanofiltration (NF) for wastewater management and metal recovery. However, conventional polyamide membranes (PA-M 0 ) exhibit poor acid resistance, compromising their long-term performance. To address this limitation, acid-resistant membranes PA-M 1 and PA-M 2 were developed by reacting PA-M 0 with 3-aminopropyltrimethoxysilane (APTMS) and ladder-like polyorganosiloxane (POS) synthesized from APTMS, respectively. After 21 days in an acidic medium (pH = 1), PA-M 0 experienced a 91.5 % flux increase and an 11.6 % Mg 2+ rejection decrease, while PA-M 1 showed a reduced flux increase of 45.1 % and a smaller rejection decline of 6.7 %. In contrast, PA-M 2 demonstrated remarkable stability, with minimal performance changes, highlighting its excellent acid resistance. Furthermore, PA-M 2 achieved superior Li + /Co 2+ separation, with Co 2+ rejection consistently above 95.3 % and a Li + /Co 2+ separation factor reaching up to 352. During 36-h NF operation at pH = 1, PA-M 0 suffered signification degradation, whereas PA-M 2 maintained stable separation performance. These findings underscore the critical role of POS, featuring abundant NH 2 groups, a dense Si-O-Si network and an ordered structure, in enhancing membrane acid resistance and selectivity. PA-M 2 presents an effective solution for treating acidic wastewater and recovering metals from spent lithium-ion battery recycling.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
Science China-Chemistry
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2022
·Vol. 65
·期 5
·943-953
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IF 10.138
Yan Yi-Teng,Wu Gang,Chen Si-Chong,Wang Yu-Zhong
The closed-loop recycling concept of the polymer wastes into building-block chemicals is attractive, but the closed-loop recycling of copolymers enabled by energy-efficient chemical recycling and cost-effective separations is still facing great challenges. Herein, for the first time, a one-pot sequential copolymerization of γ -butyrolactone ( γ -BL) and p -dioxanone (PDO) using an economical ureas/alkoxides catalytic system is conducted to synthesize biodegradable and chemically recyclable poly-( γ -butyrolactone)-block-poly( p -dioxanone) (P γ BL- b -PPDO) diblock copolymers with well-defined and controlled structures. The composition-dependent properties of P γ BL- b -PPDO copolymers, including thermal properties and crystallization behavior, are investigated. The results show that the thermal stability and crystalline ability of P γ BL are enhanced observably by introducing the PPDO block. Significantly, the P γ BL- b -PPDO copolymers can be depolymerized efficiently into the corresponding co-monomers with a yield of over 95% by simply low-temperature pyrolysis under vacuum. Moreover, γ -BL and PDO monomers are selectively separated with an isolated purity of about 99% based on the difference in their physicochemical properties. Subsequently, their repolymerization is realized to obtain the copolymers with nearly identical structures and thermostability, demonstrating the closed-loop recycling of copolymers, i.e. , polymerization-depolymerization-repolymerization. This research provides important guidance for the design of novel sustainable polymers towards more efficient chemical recycling, separation and regeneration.
研究领域:
材料科学
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环境科学
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高分子化学
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DOI
高影响因子
Journal of Cleaner Production
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2022
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IF 11.072
Yingjie Xu,Hongying Xia,Qi Zhang,Wuchen Cai,Guiyu Jiang,Libo Zhang
Germanium-containing dust as an intermediate by-product in the process of zinc hydrometallurgy , which often contains a large number of heavy metal substances. Due to the constraints of economic benefits and process technology, green and efficient treatment of germanium-containing dust is always a great challenge. In this work, XRD , ICP-OES, XPS , SEM and other characterization methods were used to analyze the existing state and quantity of main substances in germanium-containing dust. It was found that the occurrence state of germanium was closely related to sphalerite . At the same time, longer reaction time would lead to continuous hydrolysis of silicate, which would eventually affect the recovery of zinc, germanium and lead and the fixation of toxic substances. Therefore, the ultrasonic enhanced ammonium persulfate oxidation process was proposed to control the waste of resources and environmental pollution caused by the accumulation of germanium-containing dust. The final results showed that more than 95% of zinc and 89% of germanium were efficiently recovered, and heavy metals such as arsenic and cadmium were fixed in the liquid, and then concentrated in the purification and impurity removal stage. The residue after reaction is high-grade lead sulfate residue, which can be returned to the lead smelting system for recycling. In summary, the ultrasonic-enhanced ammonium persulfate process eventually makes all substances in germanium-containing dust harmless and resource treatment.
研究领域:
冶金学
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环境科学
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DOI
高影响因子
Journal of Cleaner Production
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2022
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IF 11.072
Brian Makuza,Dawei Yu,Zhu Huang,Xueyi Guo,Qinghua Tian,Kun Zhang,Baichao Zhang,Pengfei Liu
The vast amount of Lithium-ion batteries (LIBs) reaching their end-of-life calls for effective recycling processes, given the low recycling efficiency in the industry. This paper proposes an innovative sequential carbothermic reduction-selective hydrochlorination process to attain metallization of Ni-Co alloy, selective chlorination of Li, Mn, and Cu, and the formation of Al 2 O 3 to address some of the recycling challenges. The proposed process paves the way for short-range effective separation of the high-value metals in the LIB black mass based on magnetism and water solubility differences. After hydrochlorination at 1000 °C for 30 min with the material bed measuring 9 mm in thickness, Li and Mn water recovery reached 97.28% and 98.13%, respectively. The Ni and Co recoveries into the magnetic fraction reached 93.03% and 91.37%, respectively. Up to 95.28% Al, including graphite, reported to the non-magnetic fraction. Prolonged hydrochlorination time increased the chlorination degree despite negatively affecting the Ni-Co alloy recovering efficiency. Conversely, an increase in the thickness of the material bed had a reverse effect. Step-wise precipitation of the water-soluble product produced high-purity Li 2 CO 3 (≥99.5%) and Mn 3 O 4 . Compellingly, graphite with morphology and characteristic diffraction peaks and Raman bands similar to commercial graphite was regenerated by NaOH dissolution of the non-magnetic fraction. These findings demonstrate that a black mass with a complex composition (Li, Ni, Mn, Co, and Al) could be comprehensively recycled using synergetic carbothermic reduction and hydrochlorination. Besides the high recovery rates, the proposed process minimizes recycling process steps and chemical usage, which is of utmost industrial significance.
研究领域:
材料科学
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环境工程
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冶金工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2023
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IF 4.2
Mengxiang Lu,Liqiang Shao,Ying Yang,Ping Li
In view of the coexistence of lithium and boron in brines, in this article, the novel adsorption technology was developed for the simultaneous recovery of lithium and boron from brines based on the cooperative action of titanium-type lithium-ion sieves and N-methylglucamine boron specific resins. During the collaborative adsorption, lithium-ion sieves adsorbed Li+ ions based on the Li+/H+ ion-exchange mechanism, and the released H+ ions from lithium-ion sieves would be neutralized by the amine functional groups of the N-methylglucamine resins to enhance the Li+/H+ ion exchange. Meanwhile, the adjacent double hydroxyl functional groups of the N-methylglucamine resins formed preferentially the complexation adsorption with borate ions to recover boron from brines. The synergistic adsorption mechanism between lithium-ion sieves (home-made PVB-HTO granules) and N-methylglucamine boron specific resins (commercial D403 resins) was investigated experimentally in batch adsorbers. Furthermore, six groups of experiments were performed in the continuous mode for the simultaneous recovery of lithium and boron from the salt-lake brines with 50∼200 mg/L of Li and B contents and 50–200 of Mg/Li molar ratio, where three-stage continuous stirred–tank adsorbers containing 18 L of brine, 300 mL of PVB-HTO granules, and 600 mL of D403 resins were used for the lithium and boron recovery from brine. Then, the regeneration of the PVB-HTO granule-packed column by 0.3 M HCl solution was carried out to obtain the lithium-rich solution, and the regeneration of the D403 resin-packed column by 0.3 M HCl solution was performed to obtain the boron-rich solution. The feasibility and efficiencies of the adsorption method for the simultaneous recovery of lithium and boron from salt-lake brines will be evaluated.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-8
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IF 16.6
Zhang Xun,Guo Wenqi,Zhang Chengjian,Zhang Xinghong
Our society is pursuing chemically recyclable polymers to accelerate the green revolution in plastics. Here, we develop a recyclable polyester library from the alternating copolymerization of aldehyde and cyclic anhydride. Although these two monomer sets have little or no thermodynamic driving force for homopolymerization, their copolymerization demonstrates the unexpected alternating characteristics. In addition to readily available monomers, the method is performed under mild conditions, uses common Lewis/Brønsted acids as catalysts, achieves the facile tuning of polyester structure using two distinct monomer sets, and yields 60 polyesters. Interestingly, the copolymerization exhibits the chemical reversibility attributed to its relatively low enthalpy, which makes the resulting polyesters perform closed-loop recycling to monomers at high temperatures. This study provides a modular, efficient, and facile synthesis of recyclable polyesters using sustainable monomers.
研究领域:
材料科学
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高分子化学
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可持续化学
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DOI
PubMed
高影响因子
Nature Sustainability
·
2024
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IF 25.7
Zhang Gong,Li Binggong,Shi Yanfeng,Zhou Qi,Fu Wen-Jie,Zhou Gang,Ma Jun,Yin Shuo,Yuan Weihao,Miao Shiyu,Ji Qinghua,Qu Jiuhui,Liu Huijuan
Electrocatalytic nitrate reduction has great potential for simultaneously achieving ammonia recovery and nitrate-rich wastewater treatment. However, the complexity of wastewater matrices has long hampered its implementation and commercialization in the wastewater treatment industry. Here we develop a membrane-free electrochemical system, called electrochemical NO 3 − conversion synchronized with NH 3 recovery (ECSN), which synchronizes nitrate reduction with ammonia recovery for treating real nitrate-rich wastewater. Key components of this system include a 3D-printed metallic glass decorated Cu–Ni (MPCN) working electrode bearing good corrosion resistance and a UV-assisted stripping unit. When treating real electroplating wastewater, the ECSN system converts over 70% of nitrate into high-purity ammonia chloride. Long-term stability test demonstrates the robustness of the ECSN system in treating real wastewater. Further, the economic feasibility and environmental benefits of this system are evidenced by technoeconomic analysis and life-cycle analysis. Overall, this work brings the electrocatalytic nitrate reduction process one step closer to practical application, contributing to both environmental protection and the circularity of anthropogenic nitrogen flow.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2024
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IF 8.1
Huangjie Yang,Yuhao Sun,Junfeng He,Jing Li,Jianbin Li,Zhengping Ding,Yurong Ren
Due to the increasing number of spent lithium batteries (LIBs), it is imperative to recycle spent LIBs to reduce environmental pollution and raw material consumption . Here, we present a novel deep eutectic solvent (DES) composed of guanidine hydrochloride with formic acid for spent LIBs the recycling to achieve rapid and efficient leaching of cathode materials from spent LIBs and synthesis of high-quality cathode material precursors in the DES leach solution . The multifaceted characterisation of the DES leach solution has revealed the mechanisms of the novel DES leached cathode materials. Under the optimal leaching conditions, the leaching rates of Li, Ni, Co, and Mn have been explored to be 99.79 %, 98.86 %, 99.51 %, and 96.12 %, respectively. More importantly, the DES leach solution addition of oxalic acid solution can be used to synthesise the precursor and to produce LiNi 0.5 Co 0.2 Mn 0.3 O 2 with the recovered Li 2 CO 3 . Electrochemical test shows that the initial discharge specific capacity of regenerated LiNi 0.5 Co 0.2 Mn 0.3 O 2 has 162.72 mAh g −1 , which is as good as that of commercial LiNi 0.5 Co 0.2 Mn 0.3 O 2 . The entire study accomplishes the regeneration of DES, and highly efficient recovery and regeneration of cathode materials from spent LIBs. This research provides a valuable alternate treatment for various DES leach cathode materials and an efficient new method for recycling spent LIBs cathode materials.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Environmental Technology & Innovation
·
2025
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IF 7.1
Liguo Wan,Shan Yun,Lijun Zhang,Bao-Shan Xing,Benyi Xiao,Junfeng Zhai,Yu-You Li
The global scarcity of phosphorus and water resources has become a pressing environmental issue, prompting extensive research into resource recovery strategies. Wastewater generated from corn starch processing exhibits high chemical oxygen demand (COD) and elevated concentrations of nitrogen and phosphorus, and is typically treated using combined anaerobic-aerobic processes. However, effluent from secondary biological treatment still contains considerable phosphorus, with PO 4 3- -P concentrations exceeding 70 mg/L. Consequently, implementing water and phosphorus recovery processes as an alternative to conventional chemical removal methods aligns with circular economy principles and supports sustainable development goals. This study investigated the feasibility of recovering phosphorus and water from the effluent of secondary sedimentation tanks in corn starch processing wastewater using a forward osmosis-hydroxyapatite (FO-HAP) combined process and optimized the operational parameters. In the FO unit, the phosphorus concentration increased 5.9-fold compared to the feed water, reaching a PO 4 3- -P level of 210.2 mg/L, with a water recovery rate of 80 %. In the HAP-induced crystallization unit, phosphorus removal efficiency reached 98 %, and the purity of the synthesized HAP was 75 % under optimal conditions (stirring intensity of 200 rpm, pH of 10, Ca/P molar ratio of 3). Overall, the FO-HAP combined process provides an effective approach for recovering phosphorus and water from secondary effluent in corn starch processing, offering both a practical technical solution and a theoretical basis for wastewater treatment and resource utilization in the industry.
研究领域:
环境科学
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资源回收技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）