Sustainability
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2023
·Vol. 15
·期 11
·9060
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IF 3.9
Tingting Zhang,Yanling Yang,Xing Li,Zhiwei Zhou,Bigui Wei
This study investigated the ultrasonic–thermal regeneration of powdered activated carbon (PAC) spent using 4-chlorophenol (4-CP). Similarly, a thermal regeneration process was also studied and the reaction conditions (i.e., regeneration temperature, heating rate, regeneration time) were tested. Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis were applied to characterize the regenerated PACs under different treatments (thermal, ultrasonic and ultrasonic–thermal) and also compare them with the fresh and exhausted PACs. According to our regeneration observations, the ideal regeneration parameters were determined to be a 40 kHz frequency, 0.18 W/mL sonication power, 0.1 M NaOH and 50% (v/v) ethyl alcohol as the regeneration solution, and 1 g/L of saturated PAC mass with thermal regeneration as the second stage at 500 °C, desorbed for 30 min with a heating rate of 20 °C min−1. Under these conditions, the RE value achieved 90.99% and the η value reached 5.6%. The results of FTIR, XPS and XRD revealed that the oxygen functional group content of ultrasonic–thermal regenerated PAC significantly increased. These oxygenous groups exerted a positive effect on the adsorption process of the regenerated PAC and the subsequent adsorption–regeneration process.Keywords:ultrasonic;thermal;regeneration;powdered activated carbon;characteristic
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
ACS Omega
·
2020
·
IF 2.87
Yangyang Guo,Lei Luo,Yang Zheng,Tingyu Zhu
For improving the CO2 adsorption capacity of solid-supported amines, five commercial porous supports have been selected and impregnated with tetraethylenepentamine (TEPA), and their CO2 adsorption performances have been evaluated using a fixed-bed reactor coupled with mass spectrometry. For solid-supported amines, CO2 adsorption capacities coincide with the texture characterization of the adsorbent supports (mesoporous alumina, montmorillonite, silica gel, porous resin, MCM-41 molecular sieve), and the optimum TEPA loading amount is mainly affected by the pore volume. The mesoporous supports were found to be more conducive to uniform loading of organic amine, with more than 370 mg/g CO2 adsorbed per unit TEPA. Other components in flue gas, especially H2O, favor CO2 adsorption on solid-supported amines. SO2 inhibited the CO2 adsorption, which was mainly attributable to the strong and irreversible binding of SO2 on some amine sites. NO had little effect on CO2 adsorption. Thermal stabilities of solid-supported amines have been tested based on thermogravimetry curves, and the main weight loss peak for TEPA appears at 513 K for solid-supported amines. Linear and step regeneration modes have been compared, revealing that the temperature for step regeneration is 37 K lower than that for the linear regeneration mode. Moreover, the desorption peak area for the step regeneration mode is 20% higher than that for the linear regeneration mode, indicating that the step regeneration mode can be used in practical applications, to reduce energy consumption during regeneration.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Yanlong Sun,Tong Zheng,Guangshan Zhang,Bei Liu,Peng Wang,Afed Ullah Khan
ABSTRACT This work focuses on the synthesis of microwave absorbing-catalytic multifunction novel adsorbent. During adsorbent design secondary pollution produced by adsorbent regeneration is continuously neglected, which motivates the author to load catalyst on adsorbent to enhance the mineralization of adsorbed organic compounds during thermal regeneration. Microwave absorption fuels the synthesis and regeneration of adsorbent. The morphology and structure of composite adsorbent are analyzed by X-ray diffraction, scanning electron microscope-energy dispersive spectrometer, transmission electron microscope, and Brunauer–Emmett–Teller-Barrett–Joyner–Halenda method. The results show that the synthesized composite adsorbent is mesoporous with wide pore diameter distribution and 252 m 2 /g specific surface area. The host of composite adsorbent is γ-Al 2 O 3 and the loaded catalyst is amorphous manganese oxides. The synthesis process of composite adsorbent is designed and evaluated by the response surface methodology using a Box–Behnken design method. After optimization, the optimal adsorption capacity of composite adsorbent can reach up to 135 mg/g, and more than 47% tetracycline can be mineralized into H 2 O and CO 2 during 5 min regeneration. The properties of the composite material can be changed by adjusting synthesis condition. These designed functions of material will make adsorbent more adaptable to meet the growing demand of the environmental standard.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ENERGY
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2024
·
IF 9
Feifan Huang,Chao Liu,Siqin Cheng,Tao Li
Microwave thermal regeneration is an emerging technique for activated carbon regeneration, which has been extensively investigated experimentally. However, relevant simulation receives limited attention, with the mechanism of microwave thermal regeneration not very well understood. In this study, a multiphase, porous media model coupling electromagnetic , heat and mass transfer is established to study microwave thermal regeneration characteristics of spent activated carbon. The results show that inhomogeneous electromagnetic distribution in the cavity is the main factor contributing to the inhomogeneity of the sample temperature. The desorption of adsorbate in the hot spot region (dry basis) mainly relies on microwave radiation heating. The desorption of adsorbate in the cold spot region (wet basis) depends on heat conduction and convection in the hot spot region, as well as capillary diffusion caused by the concentration gradient . In addition, the uniformity of sample temperature distribution is optimized by rotating microwave thermal regeneration, and energy consumption is reduced by about 58 %. Therefore, this model can provide technical guidance for optimizing the microwave thermal regeneration process of spent activated carbon while explaining the mechanism of microwave regeneration.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Shuai Tang,Qiang Jiang,Yu Shi,Liang Zhang,Jun Li,Xuhui Jiang,Peng Zou,Zhang Luo
Thermally regenerative batteries have promising applications in low-temperature waste-heat recovery, but ammonia crossover severely reduces battery power generation and its stability. To address this issue, a membrane-less self-stratified thermally regenerative flow battery was constructed to alleviate ammonia crossover. The interface visualization, power generation feasibility, and the effects of flow rate were investigated. The results reveal that the density difference of the anolyte/catholyte leads to self-stratification. The interface moves continually due to ammonia diffusion in the static catholyte, resulting in a significant decrease in the battery performance. By regulating the catholyte flow rate, a steady anode–cathode interface can be achieved, thereby solving the key problem of ammonia crossover and achieving stable power generation. Increasing the catholyte flow rate can produce a stable interface and prevent the interface from moving to the cathode. However, a high catholyte flow rate will allow the interface to surpass the anode electrode, causing battery performance to increase and then decrease with flow rate. Increasing the ammonia flow rate can effectively improve the anode mass transfer and battery performance. The interface is affected by temperature change, so the interface is investigated at different temperatures. Within a specific range, there is no significant change in the position of the interface, and the battery’s maximum power density improves linearly with temperature.
研究领域:
能源科学
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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
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2025
·
IF 7.1
Cheng Zhang,Ziyi Yang,Jing Chen,Yifan Xu,Zezhi Chen,Huijuan Gong,Feng Lin,Houhu Zhang
Activated carbon (AC) adsorption is the primary method for removing siloxanes from biogas, but siloxane polymerization during adsorption hinders regeneration, limiting the reuse of adsorbents and long-term biogas utilization. This study investigates the thermal regeneration efficiency of copper oxide-modified activated carbon (CuO/AC) compared to conventional AC for removing octamethylcyclotetrasiloxane (D4) from biogas, and employed GPC, XPS, and theoretical calculations to elucidate the role of CuO in enhancing regeneration performance. CuO/AC achieved a regeneration efficiency of 70.3 % at 230°C, 26.9 % higher than AC, with no residual D4 detected and the formation of higher molecular weight polymers. DFT calculations indicated that Si–O bond cleavage requires less energy on CuO than on AC, consistent with XPS results, confirming that CuO acts as a Lewis acid site to catalyze the ring-opening polymerization of D4, and promote the further volatilization of PDMS depolymerization products at elevated temperatures, thereby improving the regeneration efficiency of AC-based adsorbents. This work provides new insights into the reuse of activated carbon in conventional biogas purification processes.
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
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Chenghan Ji,Hang Yu,Junhe Lu,Yi Ren,Lu Lv,Weiming Zhang
Adsorption as a desalination approach has the advantages of energy efficiency, low cost, and operational convenience, but its practical application is limited by low desalination capacity, consumption/disposal of strong acids/bases as regeneration reagents, and poor reusability. Herein, we synthesized a thermo-regenerable salt absorbent by grafting ethylenediaminetetraacetic acid (EDTA) onto a metal–organic framework (MOF), MOF-808-EDTA, which could rapidly adsorb NaCl within 30 min from saline water at 25 °C with a desalination capacity as high as 9.4 mmol/g. Moreover, the saturated adsorbent could be facilely regenerated in 80 °C water. Fourier transform infrared spectroscopy and derivative thermogravimetry revealed that temperature-regulated proton transfer between amino and carboxyl groups was the mechanism of thermo-regeneration. EDTA on MOF-808-EDTA appears in a zwitterionic state in water at room temperature, which allowed simultaneous adsorption of Na+ and Cl–. At elevated temperature, it returned to a nonionic state accompanied by the desorption of ions. A similar temperature-dependent adsorption–regeneration process was also observed for other salts, including LiCl, KCl, CaCl2, and MgCl2. Column experiments of brackish groundwater showed that 1 g of MOF-808-EDTA could produce ∼106 mL of fresh water (total dissolved solids < 600 mg/L) without significant capacity loss after 10 successive adsorption–regeneration cycles. This study is the first to propose an EDTA-based MOF for desalination and indicates the potential of MOF-808-EDTA as a green adsorbent for sustainable water desalination.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Membranes
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2025
·
IF 9.5
Junyou Li,Qilin Gu,Huiqin Zhang,Zhaoxiang Zhong,Yiqun Fan,Weihong Xing
Porous SiC membranes prepared through the reaction sintering between the additive and surface oxidation generated silica have gained increasing attention in the fields of oil-water separation. Previous efforts mainly focused on the types and contents of additives incorporated by physically mixing process, while their distribution on the microstructure and separation performance of SiC membranes has been rarely involved. This work proposed to prepare SiC membranes by uniformly coating AlOOH sol on SiC particles via the electrostatic interaction and the subsequent reaction sintering of the derived SiC@alumina core-shell particles. It is found that the surface coating enabled the homogeneous dispersion of the additives in SiC powder matrix, which not only facilitated the reactive sintering process and notably reduced the amount of residual SiO 2 in SiC membranes, but also homogenized the pore structure. Also, the oxidation pathway of SiC had been altered, which substantially retarded the oxidation degree. Impressively, the as-prepared SiC membranes exhibited 20% improvement in alkali resistance, and enhanced oil-in-water emulsion separation efficiency when compared with those prepared by the conventional mechanical mixing method. Besides, the fouled SiC membranes prepared from the core-shell units can be more efficiently regenerated by using the emerging Joule heating technique. The present work provides a facile and effective pathway to the preparation of high-performance SiC membranes through the reaction sintering of rationally designed core-shell particles for high-efficient separation.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Jiaxin Qu,Xiaoqing Dang,Li Cao,Yongkang Kou,Hongzhou Ma,He Wang,Jing Dong
The substantial energy consumption and carbon loss associated with conventional thermal regeneration of activated carbon (AC) pose significant constraints on the advancement of deactivated AC recycling. Here, a vacuum-thermal process was applied to regenerate AC saturated with VOCs. Results showed that desorption efficiency under vacuum conditions (99 % at 200 °C) was significantly higher than that in air and nitrogen (85.2 % and 86.4 %, respectively). The adsorption capacities of different AC samples were maintained at 74.2 %, 97.8 %, 90.9 %, and 96.4 % after seven regeneration cycles, respectively. Pore structure analysis showed that vacuum-thermal regeneration caused less damage to the AC pore structure compared to the air and nitrogen. In addition, micropores were shown to be most conducive to the adsorption of VOCs, while mesopores larger than 4 nm are conducive to desorption. The larger the saturated vapor pressure of the VOCs, the larger the driving force it is subjected to, and the easier it is to desorption. Density field theory (DFT) calculations showed that the higher the binding energy between VOCs and AC surface, the more stable the adsorption system, making it more difficult to regenerate the adsorbent. This work provides insight into the development of an economical and environmentally friendly regeneration route for AC adsorption.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Qiang Jiang,Yu Shi,Yichao An,Liang Zhang,Jun Li,Xun Zhu,Qiang Liao
The all-aqueous thermally regenerative battery has the advantages of high open-circuit voltage, high power density, and high Coulombic efficiency, providing a promising way for low-temperature waste heat recovery. In this study, a passive membraneless thermally regenerative flow battery driven by capillary force and gravity is proposed to reduce the cost of construction and operation. The feasibility of power generation and the influence of key parameters (height difference, support electrolyte concentration, etc.) on the battery performance are studied. The results showed that a laminar flow induced by a fiber-based microfluidic reactor could effectively separate the catholytes and anolytes, and the battery could achieve long-term power production and obtain a maximum power density of 15.2 mW cm–2. The performance of the battery first increased and then decreased with the inlet height, and the optimal height was 3 mm. This is mainly due to the fact that the inlet height affects the flow rate of the electrolyte, which affects the mass transfer and laminar flow effect in the porous electrode. Within a certain range, as the concentration of the supporting electrolyte increases, the conductivity of the electrolyte is significantly improved, although the flow rate decreases to a certain extent due to the increase in viscosity, resulting in a further improvement in the battery performance. Through the above optimization, the maximum power density of the battery obtained in this study is 24.9 mW cm–2, and the maximum theoretical thermal efficiency can reach 1.26% (the relative Carnot efficiency can reach 10.6%).
研究领域:
能源科学
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环境工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2024
·
IF 9
Yichao An,Fang Zhou,Yu Shi,Liang Zhang,Jun Li,Yu Hou,Xun Zhu,Qiang Liao
Low-temperature geothermal energy (<150 °C) is an abundant green renewable energy and non-aqueous thermally regenerative flow batteries hold immense potential for converting it into electricity. In this study, a reduced graphene oxide-modified nickel foam (RGO/NF) was developed to promote the battery performance. It was demonstrated that the low-cost nickel foam with extensive optimization potential was the desired substitute for the traditional reticulated glass carbon electrode, with a similar maximum power density (105.7 W/m 2 ). With acid treatment, a relatively rough surface with increased specific surface area was obtained, resulting in an improved performance of the battery. According to the density functional theory results, the modification of RGO on NF provided a strong microscopic interaction with Cu, accompanied by more active sites and improved wettability. Therefore, the maximum power density of the battery was increased by 21 %, while the capacity was extended by 100 % and the energy density was improved by 165 %, compared to the battery with NF. To further improve the battery performance, the flow rate and mass fraction of nano copper were optimized, exhibiting the optimal values of 35 mL/min and 15 %, respectively. The present results were competitive and helpful for future application of this technology for low-temperature geothermal energy recovery.
CAS / MDL:
研究领域:
能源材料科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2018
·
IF 3.12
Jie Tang,Bin Mu,Li Zong,Aiqin Wang
The utilization of waste products as valuable materials was a technical imperative for waste management . In this study, the cost-effective attapulgite/carbon (APT/C) composite was developed for wastewater treatment using waste hot-pot oil as a carbon precursor through a facile one-step calcination process. The APT/C composite prepared at 300°C exhibited the excellent adsorption capacity and rapid equilibrium rate over a broad pH range for the removal of various pollutants. More importantly, the removal ratios of the composites toward Methyl Violet and tetracycline still remained 77.6% and 60.2% of the initial adsorption capacity after ten adsorption–regeneration cycles via a facile thermal regeneration strategy, respectively. Beyond all doubt, this research provided a feasible and economical way for the sustainable utilization of waste hot-pot oil in wastewater treatment, achieving the concept of disposal waste with waste and recycling.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）