Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Evans Dovi,Aaron Albert Aryee,Alexander Nti Kani,Farid Mzee Mpatani,Jianjun Li,Lingbo Qu,Runping Han
This research investigated the feasibility of removing hexavalent chromium (Cr(VI) (e.g., HCrO 4 − , CrO 4 2− and Cr 2 O 7 2− ions) from water using walnut shells functionalized with amino groups (ACWNS) in a batch and continuous adsorption mode. The characterization of ACWNS was carried out utilizing FTIR, XPS , SEM, and BET methods. Adsorption was investigated in terms of pH, dose, concentration, and contact duration. Furthermore, at different temperatures, the adsorption isotherms , kinetics, and thermodynamics were studied. The Langmuir model described the experimental batch and column modes, while the Thomas and pseudo-second-order kinetics models predicted continuous and batch adsorption, respectively. The maximum uptake quantity toward Cr(VI) was 236.8 mg g –1 in batch mode and 308.4 mg g –1 in column mode at 303 K. There is some selective adsorption for Cr (VI) with some dyes coexisting in solution. Electrostatic interactions and the reduction process mediated Cr(VI) adsorption by ACWNS. The mass transfer potential (B) and the affinity between ACWNS and Cr(VI) (β) were computed using the modified mass transfer factor model. Since the attraction of Cr (VI) to ACWNS is more robust, the B value increases as the concentration increases. Again, MTZ assessment reveals that as MTZ length rises, diffusion resistance increases, resulting in increased adsorption. The adsorbent demonstrated improved regeneration capacity and therefore showed potential for the uptake of Cr(VI) ions from wastewater. Availability of data and material The dataset produced and processed during this research is available upon reasonable request from the corresponding author.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2024
·
IF 5.9
Yan Liu,Yanhong Wu,Hongchun Chen,Rujing He,Hong Xiao,Chengyi Huang,Xiaojing Wang,Zhenxing Zeng,Jinsong He,Yanzong Zhang
At present, there are few studies on the removal of water from oil, but water in fuel can cause machine malfunctions and even safety accidents, which cannot be ignored. In this study, an oil-resistant superhydrophilic/air superoleophobic sponge (SS-MS) was designed to selectively absorb water from oil. Through layer by layer deposition, polyphenols, particles, and fluorinated surfactants were assembled on the sponge, finally achieving the effect of super hydrophilic and super oil phobic in the air. The contact angle of the modified sponge SS-MS on diesel oil can reach 153°, and the absorption efficiency of water in diesel oil can reach more than 99 %. Moreover, a continuous selective absorption device for water in oil was constructed, the SS-MS sponge can still achieve a water absorption efficiency of 98 % after ten cycles. Importantly, the SS-MS has excellent mechanical and chemical stability under 80 % strain, different pH, UV irradiation times and temperatures. In addition, the materials used in this study are all green and low-pollution substances, and melamine sponge has the advantages of low price, light weight, good elasticity and high porosity. In summary, SS-MS offers a new approach to remove water from fuel and has the potential for large-scale applications.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Yong-Hui Zhang,Zuo-Bei Wang,Adenike Bernice Eloise Adeoye,Yi-Fan Wang,You-Gui Huang,Xin Ye,Wei Wang
Lanthanum (La) adsorbents are highly effective for phosphorus removal but are constrained by their high reagent cost because of their La content. By exploiting the similarity in ionic sizes between Ca 2+ and La 3+ , we develop a low-cost composite adsorbent LCCa-5@Dia by doping La 2 (CO 3 ) 3 ·8H 2 O with Ca 2+ . Our results indicate that the slow addition of NaHCO 3 during the synthetic process facilitates the incorporation of Ca 2+ into the La 2 (CO 3 ) 3 ·8H 2 O lattice, leading to an adsorption behavior nearly identical to that of the undoped adsorbents. LCCa-5@Dia demonstrates a high adsorption capacity of 60.04 mg P/g, with stable performance across a pH range of 3 to 11. Its adsorption property also exhibits excellent stability under the interference of solution pH and competing ions. Materials characterization reveals that the adsorption occurs through electrostatic attraction and ligand exchange. In continuous column-adsorption experiments, the LCCa-5@Dia adsorbent treats up to 4000 bed volumes of simulated low concentration wastewater (1.7–2.7 mg P/L). This translates to a treatment cost as low as $0.0211/m 3 . Meanwhile, the adsorbent also maintains over 80 % of the adsorption capacity after three regeneration cycles. The excellent performance and low treatment cost of the calcium-doped lanthanum carbonate adsorbents highlight its practical potential in treating low concentration wastewater.
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
POWDER TECHNOLOGY
·
2022
·
IF 5.64
Bo Lv,Bobing Dong,Chuanxiang Zhang,Zengqiang Chen,Zeya Zhao,Xiaowei Deng,Chaojun Fang
Methylene blue (MB) pollution in wastewater has become an environmental problem. Batch and continuous adsorption experiments were performed to study the adsorption mechanism of MB by coal gangue-based zeolite granules in a fluidized absorber. The results showed that MB adsorption of coal gangue-based zeolite granules was mainly chemical adsorption in a fluidized bed , which was mainly affected by its size fraction ( d ), fluid velocity ( v ), bed weight ( m ), and initial concentration ( c o ). Under suitable operating conditions ( d ≤ 0.5 mm, v = 1.3 v mf (i.e., minimum fluidization velocity), m = 100 g, and c o = 100 mg/L), the fluidized bed formed by zeolite granules had the best adsorption performance for MB, with an adsorption saturation of 0.444 g/g and an equilibrium uptake of 108.041 mg/g, which is higher than that of the traditional packed bed. The results provide a theoretical basis for the industrial application of coal gangue-based zeolite granules.
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
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2024
·Vol. 41
·期 1
·325-336
·
IF 2.9
Mofidian Roozbeh,Hosseini Seyed Sharafoddin,Miansari Mehdi,Salmani Hassan
Mazandaran wood and paper factory (MWPF) is the largest paper producer in the north of Iran. To supply raw materials for producing paper products, a forest which is located near this factory is used. The primary pollutants of this factory are solid substances, toxic substances, color, and dissolved oxygen in the water. Removing solid materials, and chemical and biological oxygen demand (COD and BOD) reduction are among the most significant problems in excluding pollution. In this study, a pretreatment process is done using aluminum chloride, impurities and initial turbidity of MWPF effluents are reduced, and COD and BOD values are removed up to 87% and 93%, respectively. After that, by a zeolite–agar adsorbent, the MWPF effluent is subjected to a continuous adsorption process, and during this cycle, more than 98% of heavy metals (HM) in the effluent are removed. The design of these tests was done by Design Expert Software. After conducting 16 trials, the optimal conditions for eliminating HM, including 2 mg/l zeolite–agar adsorbent, pH 4, temperature 40 °C, and contact time 90 min, have been obtained. In addition, the effect of temperature, contact time, pH, and adsorbent concentration on the HM removal percentage was investigated, and the results showed that the operating temperature has the most negligible effect on the HM removal efficiency. UV, XRD, FTIR, and SEM analyses were also assessed to describe the conditions better and examine the synthesized adsorbent more accurately. The adsorption equations showed a better agreement with the Langmuir model, which indicates the appropriate porosity of the nanoadsorbents.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
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