Materials
·
2025
·Vol. 18
·期 7
·1443
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IF 3.2
Yanshuang Chen,Yilin Chen,Hanqi Xu,Wenqi Zhao,Guodong Feng,Chunhui Xiao
The accumulation of coal gangue (CG), a byproduct of coal mining, poses severe environmental challenges. This study presents a green strategy to convert CG into high-value NaX zeolite via an alkali fusion–hydrothermal method. Through orthogonal experiments, the optimal synthesis conditions (solid–liquid ratio 1:8, crystallization temperature 110 °C, time 12 h) were identified, yielding NaX zeolite with exceptional crystallinity (98%), specific surface area (703.5 m2/g), and pore volume (0.28 cm3/g). Comprehensive characterization (XRD, SEM-EDS, BET, etc.) confirmed its structural integrity and thermal stability. The synthesized zeolite exhibited remarkable adsorption capacities for Cu2+(185.35 mg/g) and CO2(5.51 mmol/g), following the Langmuir isotherm model. This work not only addresses gangue disposal challenges but also demonstrates a cost-effective route for producing high-performance adsorbents, aligning with circular economy and carbon neutrality goals.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Zhenggang Huang,Chuanming Zhang,Chunyang Shen,Lili Jin,Yaxiong Zeng,Baohong Guan
Ammonia nitrogen (NH 4 + -N) is one of the regular indexes and the most important contaminants in drinking water. However, it is still a great challenge to remove low concentration NH 4 + -N from drinking water in a safe way. Here we used NaX zeolite and alkali-modified NaX zeolite (NaX-A) as adsorbents and catalysts for ozonation to remove NH 4 + -N in water without adding any chemicals. The zeolites present significant adsorption of NH 4 + -N with Freundlich adsorption affinity of 2.10–3.27 mg 1-n ·L -n ·g −1 by ion-exchange on the bridged Si-O-Al groups. The NaX-A catalytic ozonation achieves 26.7 % of NH 4 + -N removal and up to 75.0 % of gaseous products selectivity in 20 min. The NH 4 + -N oxidation rate constant is raised by 10.7 times over O 3 /NaX-A compared with single ozonation. The alkali modification stimulates the formation of acid sites in NaX-A, and thus improve the adsorption of NH 4 + -N and the decomposition of O 3 into hydroxyl radicals (·OH) for the conversion of NH 4 + -N to gaseous products. This study provides new insights into catalytic ozonation by alkali-modified zeolites to remove NH 4 + -N in water via coupling adsorption with catalytic ozonation.
研究领域:
环境科学
·
化学工程
·
水处理技术
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Likun Yang,Hua Yuan,Yongjie Shi,Shengping Wang,Xinbin Ma
An efficient alcohol adsorbent has been prepared by the NaOH etching of Na-FAU zeolite and applied for the deep removal of the alcohol from FT-mixed olefins. Due to the NaOH etching, the adsorption capacity of the NaX-2 adsorbent (85 mg/g) for n-butanol was significantly higher than the NaX adsorbent (42 mg/g). As demonstrated by SEM, 29 Si NMR, 27 Al-NMR, CO 2 -TPD, and N 2 adsorption–desorption, the etching of zeolite NaX occurs at the grain boundary, which leads to more mesopores, increased weak base sites, and Si(3Al) structure formation by alkali etching, facilitating alcohol diffusion and improving the adsorption through hydrogen bonding. In-situ FTIR and molecular simulations were employed to demonstrate the adsorption models of alcohols over Na-FAU zeolite. The hydrogen bonding network formed by dealumination finally enhances the alcohol adsorption by the hydrogen bonding by O al -H al ‧‧‧O zeo and O zeo -H zeo ‧‧‧O al . This work provides a facile preparation method for removing trace alcohol from olefins, giving promising guidance for industrial applications.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Xue-Ling Wei,Jun-Bin Zhang,Wen-Yan Pan,Bo Song,Yu-Ling Luo,Qiang Liu,Zhi-Sheng Shi,Xingyang Li,ZongCheng Miao
Zeolite membranes have excellent application prospects in the separation of mixtures with molecular-level differences; however, the uneven distribution of active ingredients on the support causes defects in the zeolite membranes, limiting their industrial applications. In this study, compact NaX and NaA zeolite membranes with perfect pervaporation performance were prepared in reusable saturated membrane synthesis solutions. These saturated membrane synthesis solutions not only provided sufficient Si/Al components for the even growth of zeolite on the support, but also reduced the random deposition of zeolite particles on the support by reducing the formation of zeolite particles in the bulk solution, improving the quality of the resulting zeolite membranes. The separation factors of the obtained NaA and NaX zeolite membranes were greater than 10000 for the water/ethanol and methanol/MTBE mixtures, respectively. Moreover, the saturated synthesis solutions could be reused multiple times to synthesize zeolite membranes after nutrient supplementation, saving resources and reducing environmental pollution. This study presents reusable solutions for synthesizing compact zeolite membranes, promoting the development of membrane technology for environmental protection and energy conservation.
研究领域:
材料科学
·
环境工程
✓ 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）