SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Lei Yao,Chao Hong,Yangxu Qi,Lie Wu
In this study, we developed a novel magnetic composite of walnut shell biochar (WSB) and modified it with ZIF-7 for the purpose of removing Co 2+ ions. We conducted a comprehensive evaluation of its performance in Co 2+ removal, considering various factors such as contact time, temperature, adsorbent dose, pH, and initial Co 2+ concentration. Utilizing response surface methodology-central composite design (RSM-CCD), we examined the interactions between these variables. The specific surface area and magnetic saturation value of the WSB/MnFe 2 O 4 /ZIF-7 composite were determined as 170.560 m 2 .g −1 and 23.469 emu.g −1 , respectively. ANOVA analysis indicated that our model effectively captures the interactions between variables, with a high R 2 value of 0.9982, explaining 99.82 % of the experimental data. Optimal conditions for maximum Co 2+ adsorption efficiency (99.05 %) were identified as follows: a contact time of 44.82 min, pH of 6.04, adsorbent dose of 0.947 mg.L -1 , temperature of 25.55 °C, and Co 2+ concentration of 11.13 mg.g −1 . Kinetic studies revealed that the Pseudo 2nd order kinetic model provided the best fit to the experimental data. The negative entropy parameter indicated a decrease in disorderliness during the adsorption process, while the exothermic nature of adsorption was confirmed by enthalpy values of −92.751 and −40.511 kJ.mol −1 for WSB/MnFe 2 O 4 /ZIF-7 and WSB, respectively. Furthermore, the Langmuir isotherm model demonstrated excellent fitting to the isotherm results, suggesting the dominance of homogeneous surfaces in adsorption. The maximum adsorption capacities for Co 2+ using WSB/MnFe 2 O 4 /ZIF-7 and WSB were determined to be 29.26 and 22.39 mg.g −1 , respectively. The WSB/MnFe 2 O 4 /ZIF-7 magnetic composite demonstrates promising potential for efficiently removing Co 2+ from both natural water sources and industrial wastewater, highlighting its versatility and effectiveness in environmental remediation applications.
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
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Ting He,Shuang Yao,Dejian Chen,Zhaoyun Sun,Xiaoyun Wang,Keyi Wang,Jiangwei Chen,Qingguo Li,Rizhi Chen,Yawei Wang,Zhaoliang Cui
Membrane oxygenator performs lung function in the Extra-corporeal Membrane Oxygenation (ECMO) system. In the clinical use, to ensure the balance of gas exchange of patient’s body, the gas-blood exchange membrane is required to possess CO 2 /O 2 selectivity, which is suggested to be in the range of 10-12. In our work, the molecular dynamics simulation results displayed that the amino-functionalized Zr-MOFs provides fast transport channels for CO 2 molecules because of the enhancement of the adsorption and diffusion ability for CO 2 . Therefore, we chose organic ligands with abundant CO 2 -philic groups to synthesize target amino-functionalized Zr-MOFs, and then dispersed them into medical-grade PDMS solution to study the separation performance of CO 2 /O 2 . On the basis of constructing anti-leakage coating layer, biomimetic gas channels were designed to increase the clearance rate of CO 2 . Experimental results exhibited that the CO 2 /O 2 selectivity of (NH 2 ) 2 -UiO-66/PDMS MMM was as high as 11.19, which was basically consistent with the simulation results. The obtained amino-functionalized Zr-MOF/PDMS coating layer displayed favorable biocompatibility and biosafety. Meanwhile, the construction of biomimetic channel solves the difficult problem of CO 2 removal in PMP membrane, which verifies the feasibility of applying porous materials to gas-blood exchange membranes in the ECMO system.
研究领域:
材料科学
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生物医学工程
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分子动力学模拟
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膜技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Yafei Guo,Changhai Li,Shouxiang Lu,Chuanwen Zhao
K 2 CO 3 supported on activated carbon (K 2 CO 3 /AC) shows promise as a potential candidate for removing low-concentration CO 2 from environmental control and life support systems (ECLSS). However, K 2 CO 3 /AC would suffer a decreased CO 2 sorption capacity due to sorbent deactivation in acid impurities such as SO 2 and NO 2 . To solve this problem, water vapor pretreatment, KOH addition and polyethyleneimine (PEI) modification were proposed as efficacious means for improving its CO 2 sorption capacity and mitigating the sorbent deactivation in these acid impurities. CO 2 sorption performances of the pretreated and modified sorbents were evaluated in a fixed-bed reactor under simulated ECLSS conditions of 20 °C, 1.0% CO 2 , 2.0% H 2 O, 30 ppm SO 2 , 20 ppm NO 2 and balanced N 2 . The mechanisms for sorbent deactivation inhibition by water vapor pretreatment, KOH addition and PEI modification were revealed by N 2 adsorption-desorption, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Effects of water vapor pretreatment duration, KOH addition and PEI loading on sorbent deactivation inhibition performances were demonstrated. Furthermore, the long-term working stabilities of the pretreated and modified sorbents in impurities were evaluated. The results will provide fundamental support on practical application of K 2 CO 3 /AC for low-concentration CO 2 removal in ECLSS.
研究领域:
环境控制与生命支持系统
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气体吸附
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材料化学
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空气净化技术
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二氧化碳捕集
✓ 已验证
DOI
高影响因子
PLoS One
·
2016
·Vol. 11
·期 7
·e0159802
·
IF 3.057
Zhujian Huang,Pingxiao Wu,Beini Gong,Yaping Dai,Pen-Chi Chiang,Xiaolin Lai,Guangwei Yu
To achieve a satisfactory removal efficiency of heavy metal ions from wastewater, silane-functionalized montmorillonite with abundant ligand-binding sites (-NH 2 ) was synthesized as an efficient adsorbent. Ca-montmorillonite (Ca-Mt) was functionalized with 3-aminopropyl triethoxysilane (APTES) to obtain the APTES-Mt products (APTES 1.0CEC -Mt, APTES 2.0CEC -Mt, APTES 3.0CEC -Mt, APTES 4.0CEC -Mt) with enhanced adsorption capacity for Co 2+ . The physico-chemical properties of the synthesized adsorbents were characterized by spectroscopic and microscopic methods, and the results demonstrated that APTES was successfully intercalated into the gallery of Ca-Mt or grafted onto the surface of Ca-Mt through Si-O bonds. The effect of solution pH, ionic strength, temperature, initial concentrations and contact time on adsorption of Co 2+ by APTES-Mt was evaluated. The results indicated that adsorption of Co 2+ onto Ca-Mt, APTES 1.0CEC -Mt and APTES 2.0CEC -Mt can be considered to be a pseudo-second-order process. In contrast, adsorption of Co 2+ onto APTES 3.0CEC -Mt and APTES 4.0CEC -Mt fitted well with the pseudo-first-order kinetics. The adsorption isotherms were described by the Langmuir model, and the maximum adsorption capacities of APTES 1.0CEC -Mt, APTES 2.0CEC -Mt, APTES 3.0CEC -Mt and APTES 4.0CEC -Mt were 25.1, 33.8, 61.6, and 61.9 mg·g -1 , respectively. In addition, reaction temperature had no impact on the adsorption capacity, while both the pH and ionic strength significantly affected the adsorption process. A synergistic effect of ion exchange and coordination interactions on adsorption was observed, thereby leading to a significant enhancement of Co 2+ adsorption by the composites. Thus, APTES-Mt could be a cost-effective and environmental-friendly adsorbent, with potential for treating Co 2+ -rich wastewater.
研究领域:
环境科学
·
化学工程
·
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）