ENVIRONMENTAL ENGINEERING SCIENCE
·
2022
·Vol. 39
·期 11
·896-905
·
IF 2.172
Zhihui Pan,Yingru Huang,Xiongrui Yang,Yilun Liang,Junguo He,Huarong Yu
In this study, an advanced temperature-sensitive hydrogel with sewage sludge ash (SSA) was synthesized and employed as draw agent for forward osmosis (FO) desalination. The effects of the incineration temperature (700–1,000°C) of SSA obtention, particle size (20–300 meshes), and dosage (0–4.5 wt%) of SSA were investigated for optimally synthesizing the temperature-sensitive hydrogel to meet the requirement of FO. The resulting hydrogels were characterized in terms of crystal structure, surface morphology, surface functional groups, and lower critical solution temperature (LCST). It was shown that the dosage of SSA significantly influenced the swelling capacity (in different concentrations of NaCl solution) and deswelling property of hydrogels, whereas the other two factors only affected the swelling of hydrogel, but had no effect on the deswelling. In addition, as a result of higher reticulated pore structure, and the hydrogen-bonding interaction between the chemical surface of SSA and monomers of hydrogels, the best production D2.5H as a draw agent generated high average water flux of 2.22 LMH in FO desalination with 2,000 ppm NaCl as feed solution. Furthermore, despite a little higher LCST with the comparison of D0H (blank sample without SSA), the D2.5H as a draw agent can still maintain the prominent temperature-sensitive performance in that, most of the water can be recovered in 10 min of 60°C water bath, and the average water fluxes of FO with even three times regenerated hydrogels were similar to that with the initial.
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
WASTE MANAGEMENT
·
2019
·
IF 5.431
Xiangdong Meng,Xiaoji Liu,Qunxing Huang,Huaping Gao,Kangrou Tay,Jianhua Yan
As a phosphorus-rich material, low-temperature combustion sewage sludge ash (LTCA) contains over 9 wt% content of phosphorus (P) and a large proportion of impurities, especially the content of Fe arrives at 14.59 wt%. To fully utilize LTCA as a fertilizer, this study investigated a procedure for P recovery from LTCA via struvite crystallization with fewer impurities. The adsorption characteristics of P and Fe by cation exchange resin (CER) were explored by simulating using the macroscopic parametric equation Thomas model. Optimum purification conditions for P-rich leachate by cation exchange column method were determined. Results showed that approximately 97.21 wt% of P was extracted from LTCA at HCl concentration of 0.8 M and liquid/solid ratio of 20.0 ml/g. More than 90 wt% of impurities could be detached by making P-rich leachate flow through cation exchange bed filled by CER at 300 ml/h. The macroscopic parametric equation Thomas model could clearly describe the adsorption characteristics of Fe in P-rich leachate by CER. Theoretical basis for purification of high concentration Fe in P-rich leachate by CER was provided. Approximately 84.04 wt% of total P in LTCA was recovered as struvite crystal which had low concentrations of heavy metals (5.96 mg/kg for Cr, 45.21 mg/kg for Cu, 29.67 mg/kg for Ni, 2.24 mg/kg for Pb, and 290.6 mg/kg for Zn) and could be eco-friendly for agricultural application. X-ray diffraction and SEM-EDS analysis validated the formation of struvite.
研究领域:
环境科学
·
农业科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Tingting Lin,Huajing Zhou,Lingxiang Zhao,Sheng Liang,Yongming Luo,Liang He,Shaoyun Shan,Tianding Hu,Zilian Liu,Wentao Du
The excellent performance of high-valent iron-oxo species (Fe IV O) in the degradation of pollutants by activating peroxymonosulfate (PMS) had attracted much attention. However, the generation and reaction mechanisms were still unclear. In this study, iron-rich paper mill sludge was used as a raw material for the first time to prepare iron-based catalysts with abundant octahedral Fe III sites (Fe oct III ). The results showed that the highest content of Fe oct III was found in the paper mill sludge ash obtained by aerobic calcination at 800 °C ( pm SA800), and the pm SA800 could exhibit excellent catalytic activity (0.4785 min −1 ) and stability during the oxytetracycline (OTC) degradation process. The characterization and density functional theory (DFT) calculations further indicated that the Fe oct III was the dominant active site for Fe IV O production. PMS tended to be adsorbed on two adjacent Fe oct III sites to form a [Fe oct III -OSO 2 OO(H)-Fe oct III ] complex with a two-site adsorption configuration. Subsequently, the O O and O H bonds in [Fe oct III -OSO 2 OO(H)-Fe oct III ] broken by absorbing energy, generating Fe IV O. It's worth noting that the Ca species of pm SA800 effectively stabilized the pH of the reaction solution, which ensured the stable and continuous production of Fe IV O. This work provides a new idea and insight for preparing catalysts that could produce Fe IV O active species.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
WASTE MANAGEMENT
·
2025
·
IF 7.1
Kun Wang,Wenzheng Liang,Sheng Yao,Xiaoying Yuan,Min Xie,Cuiping Wang
Given that both sludge ash and iron-based oxygen carriers (OCs) are rich in the active component Fe 2 O 3 , it is necessary to investigate whether there exists a synergistic effect that enhances oxygen transport and stabilizes OCs. This work focuses on lattice oxygen release characteristics and reduction kinetics of industrially prepared CaMn 0.5 Fe 0.5 O 3-δ perovskite OCs (POC), sewage sludge ash (SSA), and their 1:1 mixture (POC/SSA) using thermogravimetric analysis (TGA) via varying hydrogen concentrations (5–25 %) and terminal temperatures (800–900 °C). The results reveal that the presence of SSA slightly delays the oxygen uncoupling process of POC, with the actual weight loss being slightly higher than the theoretical weighted value. This difference diminishes as terminal temperature increases. Notably, POC/SSA exhibits significant synergistic effects under low temperatures and highly reducing atmospheres, particularly at 25 % H 2 and 800 °C, where the actual weight loss (14.52 %) exceeds the theoretical value (12.96 %). The activation energy ( E a ) of the reduction for the mixed sample is 46.135 kJ/mol, which is 1.973 kJ/mol lower than the theoretical weighted value, indicating a positive synergistic effect. This is attributed to the optimization of oxygen migration pathways via interfacial active sites and lattice defects, thereby enhancing the reactivity of POC. Furthermore, the SSA in synergy significantly increases the specific surface area of POC (from 14.28 m 2 /g to 137.6 m 2 /g) and pore volume, further improving reaction performance. This study provides valuable insights into the application of chemical looping technology for sludge treatment.
研究领域:
环境工程
·
能源材料
·
固废资源化
·
催化化学
·
热化学转化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2022
·
IF 7.34
Zhihui Pan,Xiongrui Yang,Yilun Liang,Mengze Lyu,Yingru Huang,Hong Zhou,Gang Wen,Huarong Yu,Junguo He
A temperature-sensitive hydrogel modified with sewage sludge ash (SSA) was used as an advanced draw agent for forward osmosis (FO) application in treating chromium-containing wastewater. The performance of the modified hydrogel (SSA-TSH) was measured in terms of the swelling and deswelling properties, as well as adsorption and desorption effects on Cr(VI), chemical oxygen demand (COD), total phosphorous (TP) and ammonium (NH 4 + -N) in chromium-containing wastewater. Furthermore, the efficiencies of wastewater treatment , water flux , and the reusability of the SSA-TSH as draw agent in the FO process (FO-SSA-TSH) using a commercially available thin-film composite membrane (Sterlitech) were also investigated. The results indicated that FO-SSA-TSH achieved high removal rates of pollutants (Cr(VI): 96.9 %–97.4 %, COD: 97.1 %–97.4 %, TP: 97.7 %–99.6 %, and NH 4 + -N: 76.8 %–77.9 %) in various Cr(VI) concentrations (0– 40 mg/L) due to the high rejection rate of FO membrane and notable adsorption capacity of the hydrogel. Moreover, the average water flux of FO-SSA-TSH (1.95– 2.02 LMH) was nearly twice as much as that of the FO with pure temperature-sensitive hydrogel as draw agent (FO-TSH, 1.33– 1.42 LMH) in 24 h chromium-containing wastewater treatment . In addition, SSA-TSH with excellent deswelling property exhibited high water recovery performance and good reusability in low cost and energy consumption after the FO permeation process for wastewater treatment.
研究领域:
环境工程
·
废水处理
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
DESALINATION
·
2021
·
IF 9.501
Zhihui Pan,Haoyong Guo,Huarong Yu,Gang Wen,Fangshu Qu,Tingjian Huang,Junguo He
This work made use of the sewage sludge ash (SSA) to enhance thermo-responsive hydrogel for driving forward-osmosis (FO) process. Results showed that owing to the porous structure and intermolecular interactions between the ionized groups of monomers and the chemical surface of silica , the SSA-based thermo-responsive hydrogel (SSA2.5H) had increased swelling capacity and osmotic pressure , resulting in an average water flux (2.33 LMH) twice as high as the hydrogel without adding SSA (1.18 LMH) during 24 h FO with DI water or different concentrations (2000–8000 ppm) of NaCl as feed solution. More importantly, SSA2.5H can maintain good thermo-responsive dehydration performance in spite of an enhancement to its swelling ability. 93.8% of the adsorbed water can be retrieved from SSA2.5H in water bath of moderate temperature (60 °C) for 10 min and water flux can be recovered to 94.4% of the initial value after 4 times of hydrogel regeneration during FO as draw agent. Therefore, this work showed that SSA was an excellent modifier to enhance the thermo-responsive hydrogel for improving permeation performance in FO and lowering down the actual energy requirement for water recovery and draw agent regeneration.
研究领域:
环境科学
·
材料科学
·
水处理
✓ 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）