CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Taoqin Chen,Longqian Xu,Sheng Wei,Zhiqiang Fan,Ruibo Qian,Xueli Ren,Guo Zhou,Hongquan Yang,Jiayun Wu,Hongbin Chen
The conventional technologies for ammonia recovery from wastewaters usually requires high chemicals and energy input. And if the wastewater contains hardness, there is a risk of scaling with increasing in cost. Flow electrode capacitive deionization (FCDI) coupled with monovalent cation exchange membrane (MCEM) was employed to solve abovementioned problem. Our method was an effective strategy for the selective production of an ammonia-rich solution from coal gasification gray water by simply adjusting the charging and discharging processes. During the charging process, both NH 4 + and Na + were transported to the cathode due to electrosorption of the electrical double layers (EDLs) on charged carbon particles and electrodialysis of potential gradient, while Ca 2+ was retained by the MCEM. The Faradaic reactions induced the generation of OH - and led to the conversion of charged NH 4 + into uncharged NH 3 . When the electrode polarity was reversed, charged species such as Na + would be mostly pushed back into the spacer chamber, yet NH 3 was more likely to be trapped in the cathode due to sluggish pH variations, thereby producing an ammonia-rich solution. Under optimal operating conditions (i.e., a carbon content of 5 wt%, charge and discharge voltages of 4.5 and 0.2 V, respectively, charge 80 min and discharging 15 min, and six continuous cycles), a stable recovery efficiency (∼205 mg/L per cycle) and product purity of 70.4% were attained at a relatively low electrical energy consumption (11.1 kWh/kg N). Additionally, Ca scale was effectively avoided by MCEM. These results demonstrated that FCDI coupled with MCEM could be a promising technology for efficient NH 4 + removal, recovery as an ammonia-rich solution and TOC removal from industry wastewaters with alleviation of scaling.
研究领域:
环境工程
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化学工程
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DOI
高影响因子
Journal of Building Engineering
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2024
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IF 6.7
Jixi Chen,Jinqing Jia
To enhance the engineering application range of fly ash-cement-based materials (FCM), the combined effects of hardening accelerator on FCM were investigated by using response surface methodology (RSM). Based on a three-factor three-level Box-Behnken design (BBD), the linear, quadratic and interaction relationships between the dosages of calcium chloride (CaCl 2 ), aluminum sulfate (Al 2 (SO 4 ) 3 ) and triethanolamine (TEA) on the primary properties (setting time, mechanical properties and shrinkage rate) of FCM were discussed. The prediction model was established to determine the optimal ratio of the composite system . The microscopic performance and the mineral fraction of the paste were explored by using X-ray diffraction (XRD), thermogravimetric differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Results indicated that the paste performance was affected by the interaction of multiple factors, and the interaction between CaCl 2 and Al 2 (SO 4 ) 3 was the most significant. The optimum ratio of paste was 2.81 % CaCl 2 , 0.75 % Al 2 (SO 4 ) 3 and 0.12 % TEA, achieving a 28 d compressive strength of 40.48 MPa, closely matching the predicted value. The dominant hydration products of the composite cementitious system were C–S–H gel, AFt and Friedel's salt, with changes observed in the morphology of CH. With the prolong of curing age, the hydration products and unhydrated fly ash particles were bonded to each other, so that the slurry maintains a certain strength performance.
研究领域:
土木工程
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材料科学
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产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
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2024
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IF 7.4
Jixi Chen,Jinqing Jia,Mengyu Zhu
With an optimized dosage, hardening accelerators become a vital means of modifying fly ash-cement system (FAC). This study comprehensively investigated the mechanical properties of FAC modified by Li 2 CO 3 , Na 2 SO 4 , and triethanolamine (TEA) under different dosages, and optimized the dosage of accelerators through the response surface method (RSM). The synergistic effect of accelerators on the hydration of FAC was characterized by thermogravimetric differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results demonstrated that the factors and response value followed a quadratic polynomial model. The regression coefficients R 2 of the model were all greater than 0.9, indicating good agreement with the experimental data. The content of Li 2 CO 3 and Na 2 SO 4 had an extremely significant effect on the compressive strength of 1d and 3d, followed by TEA. The optimal mix ratio predicted by RSM was 0.12 % Li 2 CO 3 , 0.47 % Na 2 SO 4 , and 0.40 % TEA. Early hydration stages revealed that the combined action of these accelerators increased the formation of CH, CaCO 3 , and amorphous C-(A)-S-H gel. Microscopically, the surface of fly ash exhibited alkali-induced corrosion, thereby enhancing its pozzolanic reactivity.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
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2025
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IF 13.1
Ruidan Liu,Pan Feng,Zhaolong Liu,Long Yuan,Guanghui Tao,Zhenqi Yu,Xiangyu Meng,Jian Chen
The rapid advancement of renewable energy highlights the urgent need for safe, cost-effective, and scalable energy storage solutions, particularly for net-zero energy buildings. In this study, we introduce an innovative energy storage solution utilizing fly ash-cement composites (FCS) as multifunctional components. The FCS, incorporating fly ash as a mineral admixture, achieves a refined pore structure and homogeneous air void distribution during early hydration, leveraging the ball-bearing characteristics and pozzolanic effect of fly ash. The optimized FCS, containing 50 wt% fly ash, exhibited an impressive ionic conductivity of 25.6 mS cm −1 and a compressive strength of 5.5 MPa after just one day of curing. When integrated into structural energy storage systems, it delivers a high specific capacitance of 102.4 mAh g −1 at 0.1 A g −1 , an energy density of 73 Wh kg −1 , and a power density of 76.3 W kg −1 , maintaining 92.9 % capacitance retention over 2000 cycles. These results underscore the scalability, cost efficiency, and structural benefits of FCS, offering a promising pathway to integrate energy storage directly into buildings and infrastructure. Moreover, this strategy provides a sustainable, high-value application for large volumes of industrial solid waste while addressing energy challenges in extreme environments such as deep-sea, deep-earth, and extraterrestrial constructions.
研究领域:
土木工程
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能源存储
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2024
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IF 6.3
Yining Dai,Yanling Yang,Xing Li,Nan Wang,Zhiwei Zhou,Jianyong Feng,Yongwang Liu,Hang Li
Reusing treated greywater indoors in buildings is an advanced strategy to increase the utilization of limited water resources , but currently there is a lack of feasible technologies for efficiently purifying greywater indoors. In this study, we construct the heterogeneous TiO 2 -stainless steel mesh (SSM) interface with photocatalytic degradation of sodium dodecylbenzene sulfonate (SDBS) by under vacuum ultraviolet (VUV) irradiation. At the initial SDBS of 10 mg/L, the degradation rates of SDBS with UV/TiO 2 -SSM and VUV/TiO 2 -SSM process were 53 % and 74 % respectively within 50 min. The results of specific scavengers experiments and EPR analysis revealed that the ·OH, h + and direct photolysis contributed to SDBS degradation and mineralization . The degradation rate of SDBS in VUV/TiO 2 -SSM process was higher at weak acid or weak alkali conditions, while the performance of UV/TiO 2 -SSM process was better at alkaline conditions. Both Cl − and HCO 3 − could inhibit SDBS degradation, while SO 4 2− slightly promoted the degradation. Active oxygen species mainly degrade SDBS in two ways: by attacking the α carbon, β carbon, or branched chain carbon on the alkane chain ; or by attacking the adjacent carbon on the alkane chain, resulting in the formation of three branch forms of products. The toxicity of the intermediate products shows a decreasing or stable trend. The experiment shows that UV or VUV photocatalytic TiO 2 -SSM has a good prospect of removing anionic surfactant in the real greywater. This study provides strategies for the development and design of indoor water reuse technologies and devices in buildings.
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 Environmental Chemical Engineering
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2022
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IF 7.968
Hang Li,Yanling Yang,Jiawei Ren,Zhiwei Zhou,Xing Li,Yuankun Liu,Jianyong Feng
Pre-ozonation is often used as an effective method to assist coagulation in removing organic contaminants . In this study, a new process that combining ozone (O 3 ) with vacuum ultraviolet (VUV/UV) process (VUV/UV/O 3 ) is investigated to enhance the removal of organic matters in greywater from public buildings or household. The influence of organic characteristics (molecular weight distribution, hydrophobicity , and fluorescence) in greywater on VUV/UV/O 3 enhanced coagulation has not been fully studied. Herein, organic matters of greywater were separated and classified, and fates of organic fractions by VUV/UV/O 3 enhanced coagulation were clarified. Greywater contains tryptophan-like and tyrosine-like proteins, and terrestrially derived humic-like substances. The highest UV 254 , LAS , DOC and COD Cr removal efficiency from greywater could reach up to 47.54%, 58.92%, 17.96% and 15.76% in VUV/UV/O 3 enhanced coagulation, respectively. The removal efficiency of tryptophan-like and tyrosine-like in filtrates of varied molecular weight ranges by VUV/UV/O 3 enhanced coagulation was 93.59%–98.13% and 89.86%–95.53%, respectively. VUV/UV/O 3 enhanced coagulation was effective for the removal of bio-polymers, humic substances and low molecular weight acid ≤ 30 kDa, while it was insignificant for that of 0.22 µm - 100 kDa. Particle size of flocs increased significantly in filtrates obtained from increasing membrane pore size, indicating that macromolecular organic matter was more likely to form flocs. Finally, the VUV/UV/O 3 could improve coagulation on the removal of varied organic pollutants and improve sedimentation by changing the flaky flocs to dense ones. Therefore, the results demonstrate VUV/UV/O 3 is an effective pre-oxidation method to enhance the effect of coagulation on greywater treatment.
研究领域:
环境科学
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水处理工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Zhiqin He,Yun Li,Benkun Qi
Utilization of greywater can relieve the pressure of water scarcity. However, the widespread presence of anionic surfactants in greywater poses threats to the environment and the health of the human and ecosystem. In this study, bioinspired polyethyleneimine-tannic acid (PEI-TA) complexes were innovatively used for coating of corn straw (CS) and the as-prepared PEI-TA modified CS (PEI-TA@CS) was applied for adsorptive removal of the commonly found sodium dodecylbenzene sulfonate (SDBS) in greywater. The adsorption performance of the modified CS was maximized under the following optimized preparation conditions: 5 g/L of PEI concentration with molecular weight of 3000 Da, 0.5 g/L of TA concentration and 3 h of modification time. Investigation of the adsorption conditions showed that adsorption of SDBS on the adsorbent were pH-independent at pH ≤ 7 and the adsorption process reached equilibrium in about 3 h. The pseudo-second-order model and Freundlich model fit well the kinetic and isotherms data, respectively, and the nature of the adsorption was exothermic and spontaneous. Mechanism analysis showed that the adsorption of SDBS was dominated by hydrophobic interactions. With a dosage of 100 mg, PEI-TA@CS could satisfactorily remove 94.95 % of SDBS from its aqueous solution (50 mg/L). Even in the complex synthetic greywater, the removal of SDBS still reached as high as 81.99 %. The overall results indicated that PEI-TA@CS has promising applications in the removal of anionic surfactants from greywater.
研究领域:
环境科学
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水处理
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）