Desalination and Water Treatment
·
2016
·
IF 1.272
Xiaoliang Ma,Hong Peng,Xu Zhang
This study systematically investigated the adsorption properties of 2,4-dinitrophenol (DNP) on granular activated carbon (GAC), and the performance of ultraviolet (UV) light irradiation and solvent extraction in the regeneration of spent adsorbent. It also evaluated the influence of such regeneration on the change of GAC surface properties. The adsorption followed a pseudo-second-order kinetic model and was controlled by the intra-particle diffusion rate process. With an adsorption capacity of 1,476 μM (272 mg/g), the adsorption of DNP onto GAC fit the Dubinin–Astakhov mode better than it did the Freundlich and Langmuir isothermal models. These results indicate that the adsorption occurred not only on the surface, but also in the micropores and mesopores. The regeneration efficiency of spent GAC was less than 10% using either UVC or vacuum UV irradiation, which was probably because the irradiated light could not directly enter the pores to induce the degradation of the adsorbed DNP. The levels of regeneration efficiency by ethanol extraction and acetic acid extraction were 60 and 100%, respectively, in the first cycle. The surface area was slightly decreased, while the porosity and surface composition were maintained after solvent extraction.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
·
2021
·
IF 8.001
Hongyou Wan,Fuzhen Wang,Yuhan Chen,Zisheng Zhao,Guangyi Zhang,Ming Dou,Binghan Xue
In this study, nano-Fe 3 O 4 supporting on granular activated carbon (NFGAC) were prepared, characterized and used as an individual additive to promote the anaerobic digestion of azo dye Reactive Red 2 (RR2) wastewater. Results showed that organics removal and methane production were effectively promoted with the addition of NFGAC. Compared with the control reactor, the RR2 removal efficiency increased by 117.9% and the methane production increased by 167.2% in the 0.18-NFGAC added reactor when sole RR2 used as the substrates. Further analysis indicated that during the RR2 anaerobic digestion process the electron transfer system (ETS) activity was effectively improved with the addition of NFGAC. One of the possible mechanism was that the loading nano-Fe 3 O 4 on the surface of GAC could increase the number of functional groups in NFGAC, which were beneficial to enhancing the electron accepting capacities (EAC) and electron donating capacities (EDC). Microbial community analysis showed that the bacteria ( Halomonas , Pseudomonas and Bacillus ) relevant to RR2 removal were enriched in NFGAC added reactors, which played an important role during RR2 removal process. In addition, the addition of NFGAC could promote potential direct interspecies electron transfer (DIET) between Pseudomonas and Methanosarcina.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2020
·
IF 5.778
Jing Li,Kangmeng Zhu,Ruimeng Li,Xiaohui Fan,Heng Lin,Hui Zhang
Granular activated carbon (GAC) was used as catalyst for the activation of peroxydisulfate (PDS) to decolorize and degrade Acid Orange 7 (AO7) in water. EPR spectra and radical quencher experiments were employed to identify the active species for AO7 oxidation in the PDS/GAC system. Linear sweep voltammetry (LSV) and chronoamperometry test were carried out to identify the contribution of nonradical mechanism for AO7 decay. The investigation of crucial operational parameters on the decolorization indicated 100 mg/L AO7 can be almost totally decolorized in a broad range of pH. Common inorganic anions adversely affect the AO7 decolorization process and the inhibition was in the order of: HCO 3 − > H 2 PO 4 − > SO 4 2− > Cl − > NO 3 − . UV–vis spectra showed the destruction of the aromatic moiety of AO7 molecule during the oxidation reaction of the PDS/GAC system. The transformation of nitrogen related to the azo bond in AO7 molecule in this system was observed by monitoring the released N-containing inorganic ions. Recycle experiments showed GAC cannot be reused directly but its catalytic ability can be restored by using electrochemical method .
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE
·
2011
·
IF 1.293
Jo Anne G. Balanay,Shaun A. Crawford,Claudiu T. Lungu
Activated carbon fiber (ACF) has been demonstrated to be a good adsorbent for the removal of organic vapors in air. Some ACF has a comparable or larger surface area and higher adsorption capacity when compared with granular activated carbon (GAC) commonly used in respiratory protection devices. ACF is an attractive alternative adsorbent to GAC because of its ease of handling, light weight, and decreasing cost. ACF may offer the potential for short-term respiratory protection for first responders and emergency personnel. This study compares the critical bed depths and adsorption capacities for toluene among GAC and ACF of different forms and surface areas. GAC and ACF in cloth (ACFC) and felt (ACFF) forms were challenged in stainless steel chambers with a constant concentration of 500 ppm toluene via conditioned air at 25°C, 50% RH, and constant airflow (7 L/min). Breakthrough data were obtained for each adsorbent using gas chromatography with flame ionization detector. Surface areas of each adsorbent were determined using a physisorption analyzer. Results showed that the critical bed depth of GAC is 275% higher than the average of ACFC but is 55% lower than the average of ACFF. Adsorption capacity of GAC (with a nominal surface area of 1800 m2/g) at 50% breakthrough is 25% higher than the average of ACF with surface area of 1000 m2/g, while the rest of ACF with surface area of 1500 m2/g and higher have 40% higher adsorption capacities than GAC. ACFC with higher surface area has the smallest critical bed depth and highest adsorption capacity, which makes it a good adsorbent for thinner and lighter respirators. We concluded that ACF has great potential for application in respiratory protection considering its higher adsorption capacity and lower critical bed depth in addition to its advantages over GAC, particularly for ACF with higher surface area.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2023
·Vol. 98
·期 9
·2224-2234
·
IF 3.4
Hao Fu,Yongwen Ma,Jinquan Wan,Yan Wang,Yingping Long,Jianye Cao
BACKGROUND Most studies have focused on the degradation of acrylamide (AM) by a single strain. There are relatively few studies on the treatment of AM by anaerobic activated sludge. Previous studies have shown that conductive particles can change the mode of electron transport between anaerobic microorganisms. Therefore, this study compared the enhancement effect of three different particles (Fe 3 O 4 , granular activated carbon (GAC), graphite) on the treatment of synthetic AM wastewater by anaerobic activated sludge under different temperature conditions (30, 25, 20 °C) and particle dose (2, 6 g L −1 ). RESULTS The results showed that 6 g L −1 GAC improved the removal rate of chemical oxygen demand (COD) and AM by 22.95% and 19% compared with the control group at 30 °C, respectively, indicating that the addition of GAC contributes to the degradation of AM and improves COD removal rate. Results of high-performance liquid chromatography (HPLC) showed that the activated sludge with GAC obviously promoted the degradation of AM. Besides, a large amount of propionic acid was detected in all experimental groups during the reaction, and the activated sludge with GAC promoted degradation of propionic acid. CONCLUSION Anaerobic activated sludge supplemented with sufficient GAC can not only absorb and degrade AM synchronously but also accelerate the conversion of intermediates, such as acrylic and propionic acids. Based on the results of HPLC and liquid chromatography–mass spectrometry, a possible method of degradation of AM by anaerobic activated sludge was proposed. © 2023 Society of Chemical Industry (SCI).
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Ruya Chen,Xin Huang,Guiwei Li,Ying Yu,Baoyou Shi
Granular activated carbon (GAC) adsorption is one of the best available technologies for removing perfluoroalkyl substances (PFASs) from drinking water . However, GAC processes in full-scale drinking water treatment plants frequently encounter unstable, even negative removal efficiency on PFASs due to the lack of understanding between the GAC characteristics and the PFASs polluted water quality conditions. In this study, the scenarios of raw water pre-chlorination and emergency contamination by multiple PFASs were simulated to evaluate the PFASs control performance by in-service GAC with different properties and ages. The results showed that the adsorption of a relatively longer-chain PFAS by the in-service GAC can be achieved by replacing the pre-adsorbed natural organic matter (NOM). The increased lower molecular weight NOM after pre-chlorination could compete with PFASs for adsorption sites and exacerbate the pore blockage, thus significantly weakening the PFASs removal ability of in-service GAC. When multiple PFASs entered the water by emergency contamination, the PFASs with stronger hydrophobicity could replace the PFASs with less hydrophobicity that had previously been adsorbed on GAC. GAC with a higher proportion of micropores had a lower risk of PFASs leakage facing the water quality changes.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
Chemical Engineering Journal Advances
·
2025
·
IF 7.1
Yifan Chen,Xiaolong Gong,Peishan Yang,Mingxin Zhu,Hua Zhou,Shunlong Pan
The advanced removal of organic pollutants from reverse osmosis concentrate (ROC) remained challenging due to the limitations of cost-efficiency in conventional treatment processes. This study proposed a novel integrated approach combining granular activated carbon (GAC) adsorption with ozone regeneration (GAC/O₃) for effective ROC remediation. The process involved two sequential stages: (1) adsorption of organic pollutants onto GAC until saturation, followed by (2) ozone-induced degradation of the adsorbed contaminants through in-situ regeneration. Continuous-flow experiments demonstrated that the hybrid GAC/O₃ system achieved a 63.6 % reduction in dissolved organic carbon (DOC) concentration (from 44.18 mg/L to 16.09 mg/L) over five consecutive cycles, with ozone consumption significantly reduced by 10.9-fold (4.9 mg O₃/mg DOC) compared to standalone ozonation. Mechanistic analyses revealed that organic pollutant adsorption was dominated by π–π interactions between aromatic moieties and pore-filling effects. The oxygen-containing groups on the surface of GAC, phenolic hydroxyl and carboxyl group, were used to active O 3 to form hydroxyl radical for the adsorbed organic pollutants destroyed. This work provided a theoretical foundation for the GAC/O₃ system as a sustainable strategy to enhance ROC treatment efficiency.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2024
·Vol. 235
·期 8
·1-12
·
IF 3.8
Li Qi,Zhu Yanping,Liu Yanbiao,Chen Xiaoguang,Jiang Nan,Yan Mengying,Li Xuhua,Xing Haoyu,Bao Yinzhou,Huang Manhong
Antimonate (Sb(V)), sulfate and acid orange 7 (AO7) are common pollutants in printing and dyeing wastewater. Currently, there have been no reports about the effects of sulfate and AO7 on Sb(V) removal by anaerobic granular sludge (AnGS). In this study, the Sb(V) removal and Sb(Ш) accumulation was revealed in presence of sulfate and AO7, and the role of adding granular activated carbon (GAC) was investigated. Results showed that sulfate inhibited Sb(V) removal by AnGS (S + Sb, k = 0.101). GAC alleviated the inhibition of sulfate on Sb(V) removal and Sb(V) removal rate increased by 1.9 times (GAC + S + Sb, k = 0.187). Meanwhile, GAC promoted sulfate reduction by AnGS. AO7 inhibited sulfate reduction, thereby alleviating the inhibition of sulfate on Sb(V) removal, and Sb(V) removal rate increased by 1.5 times (S + Sb + dye, k = 0.147). When Sb(V), sulfate and AO7 coexisted, adding GAC actually inhibited Sb(V) removal (GAC + S + Sb + dye, k = 0.067), which may be due to GAC promoted the reduction of sulfate and AO7 by AnGS. The microbial community analysis revealed that Acinetobacter genus was related to Sb(V) reduction, with higher relative abundance in GAC + S + Sb (49.4%) and S + Sb + dye groups (28.9%). These results provided guidance for anaerobic treatment of printing and dyeing wastewater. Graphical Abstract
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Jianhong Xu,Zuwen Liu,Dongye Zhao,Naiyun Gao,Xie Fu
A new composite material (Fe 3 O 4 @GAC, Fe 3 O 4 nanoparticles loaded on a commercial granular activated carbon (GAC)) was prepared through a facile hydrothermal process at controlled Fe 2+ :Fe 3+ molar ratios in air. Fe 3 O 4 @GAC was thoroughly characterized and tested for adsorption of perfluorooctanoic acid (PFOA) in water. Fe 3 O 4 @GAC(2:1), prepared at an Fe 2+ :Fe 3+ molar ratio of 2:1, showed the best PFOA removal and offered 28.8% higher adsorption capacity than the parent GAC at final pH 4.0. The enhanced adsorption of PFOA was attributed to concurrent hydrophobic, electrostatic and complexation interactions between PFOA, GAC and Fe 3 O 4 . GAC in the composite played an important role for PFOA adsorption. The presence of Ca 2+ ions (10 mM) at final pH 5.0–10.0 more than doubled the PFOA equilibrium uptake of PFOA by Fe 3 O 4 @GAC(2:1) due to the calcium bridging effect between PFOA and the Si-OH or Fe-OH groups in Fe 3 O 4 @GAC(2:1), and because of the Ca 2+ -modification induced formation of PFOA hemi-micelles on the surface or in the relatively large pores (2.27 nm) of Fe 3 O 4 @GAC(2:1). Fe 3 O 4 @GAC(2:1) was amenable to efficient regeneration using a mixture of NaOH solution and methanol. Fe 3 O 4 @GAC holds the potential to be used as a simple and low-cost adsorbent for enhanced adsorption of PFOA, especially in waters of high hardness and alkalinity.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Xin Huang,Mengze Geng,Kaiyun Wang,Yitian He,Guiwei Li,Chenghong Feng,Baoyou Shi
Extending the lifetime of granular activated carbon (GAC) filters with no significant loss in their effectiveness is a considerable challenge for drinking water supply utilities. However, the effects of residual Al from coagulants on GAC performance are rarely considered. Herein, in-service GAC samples obtained from full-scale water treatment plants were investigated to evaluate the amount of accumulated Al. Although the Al concentration in water was two to three times lower than the Ca concentration, Al exhibited considerable accumulation (second to Ca accumulation) in in-service GAC samples (0.68–8.63 mg g −1 ). Surface characterization results indicated that Al accumulation could have been caused by the co-precipitation of Al with Ca and Si to form Ca 4 Al 2 Si 3 O 10 ·H 2 O and Ca 4 Al 6 O 12 SO 4 , self-precipitation or complexion with −OH/−COOH on the GAC or biofilm surfaces. Correlation analysis of the accumulated Al and GAC properties implied that Al accumulation considerably reduced the surface area of GAC by ∼30%. Lab simulation experiments indicated that the removal of dissolved organic matter was reduced by 6–10% when additional Al was loaded. In addition, results showed that the residual Al (up to 200 μg L −1 ) considerably affected the extracellular polymeric substance component and microorganism community structure. In summary, strict control of residual Al is beneficial for maintaining the efficacies of GAC and biologically activated carbon.
研究领域:
环境工程
·
水资源管理
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2017
·
IF 5.651
Zhi-Yi Ni,Jing-Ya Li,Zhao-Zhao Xiong,Li-Hua Cheng,Xin-Hua Xu
Microalgal wastewater treatment has been considered as one of the most promising measures to treat nitrogen and phosphorus in the municipal wastewater. While the municipal wastewater provides sufficient nitrogen and phosphorus for microalgal growth, the microalgae still faces serious biological contamination caused by bacteria in wastewater. In this study, the commercial granular activated carbon (GAC) was added into the simulated municipal wastewater to avoid the influence of bacteria on the growth of microalgae. The extracellular organic matter (EOM) in microalgal broth was then characterized to enlighten the role of GAC in reducing the bioavailability of EOM. The results showed that the GAC addition could increase the dry weight of microalgae from 0.06 mg L −1 to 0.46 mg L −1 under the condition of bacterial inoculation. The GAC could mitigate bacterial contamination mainly due to its adsorption of both bacteria and EOM that might contain algicidal extracellular substances. Moreover, compared to the control group, the GAC addition could mitigate the microalgal lysis caused by bacteria and thus greatly reduce the bioavailability of EOM from 2.80 mg L −1 to 0.61 mg L −1 , which was beneficial for the improvement of biostability and reuse of effluent after the microalgal harvesting.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Bing Zhang,Xin Mao,Yu Shen,Tengfei Ma,Bing Zhang,Bin Liu,Wenxin Shi
The structural variances of adsorbents play a crucial role in determining the number of effective adsorption sites and pretreatment performance. However, there is still a gap in comprehending the impact of different carbon structural adsorbents on membrane fouling . Therefore, this study aimed to compare the efficacy of granular activated carbon (GAC), powdered activated carbon (PAC), and activated carbon fiber (ACF) in mitigating membrane fouling during municipal sewage reclamation using an aerobic granular sludge membrane bioreactor (AGMBR). The results demonstrated that the utilization of PAC significantly enhanced the normalized flux and reduced fouling resistance in comparison to GAC and ACF systems. PAC effectively adsorbed low and medium-molecular-weight pollutants present in raw sewage, resulting in an increase in average particle size and a decrease in foulant content on the membrane surface. The Hermia model indicated that adsorption pretreatment minimized standard blocking while promoting the formation of a sparse and porous cake layer. Moreover, according to the extended Derjaguin–Landau–Verwey–Overbeek theory, PAC has been demonstrated as the optimal antifouling system owing to its enhanced repulsion between membrane-foulant and foulant-foulant interactions. Correlation analysis revealed that the exceptional antifouling performance of the PAC system was due to its high removal rates of chemical oxygen demand (~78 %) and suspended solids (~97 %). This research offers valuable insights into the mitigation of membrane fouling through the utilization of adsorbents featuring diverse carbon structures .
研究领域:
环境科学
·
污水处理
✓ 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）