INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2018
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IF 3.141
Weiping Kong,Yong Liu,Fujian Liu
Efficient micro-meso-macroporous solid acids spheres with controllable acid strength were successfully synthesized by simultaneous grafting of −SO3H and −SO2CF3 onto the network of commercial XAD-4 resin. The synthesized solid acids are designated as XAD-4-SO3H and XAD-4-SO3H-SO2CF3. Various characterizations show that XAD-4-SO3H and XAD-4-SO3H-SO2CF3 possess high BET surface areas, hierarchical porous structures with combined micro-meso-macropores, high concentrations of acid sites, and strong acid strength. Catalytic tests show that XAD-4-SO3H and XAD-4-SO3H-SO2CF3 exhibit superior activities and good reusability in various acid-catalyzed reactions including esterification of acetic acid with cyclohexanol, acylation of anisole with acetyl chloride, and catalytic synthesis of bisphenol A. Their activities were better than the solid acids of Amberlyst-15, SBA-15-SO3H-0.1, H3PW12O40, and acidic zeolites. This work develops a new method for scalable transformation of commercially macroporous resin into efficient porous solid acids, which promotes their wide use in industrial catalysis.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 30
·期 13
·38174-38184
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IF 5.19
Zhang Ziang,Ma Yan,Li Aimin,Pan Yang,Yao Qianqian,Jia Xiaorui,Zhou Qing
The hydrophilic substances in natural organic matter (NOM) are the main precursor of disinfection by-products (DBPs) formed during disinfection processes. The fractionation of the components in NOM based on hydrophilicity contributes to elaborating the behavior of NOM during disinfection. However, the traditional NOM fractionation method using two hydrophobic resins of DAX-8 and XAD-4 lays emphasis on the separation of hydrophobic substances, limiting the thorough study of the hydrophilic components in NOM. In this work, the amphiphilic resin NDAM was employed as a replacement of XAD-4 to realize more thorough separation of the hydrophilic substances. Compared with the divinylbenzene (DVB) structure of XAD-4, the NDAM possesses a more hydrophilic skeleton of N-vinylpyrrolidone (NVP) and DVB which favors the adsorption of hydrophilic components in NOM. The two fractionation methods of DAX-8 + XAD-4 and DAX-8 + NDAM were applied to fractionate NOM, and the obtained fractions were characterized via fluorescence spectra, UV spectra, acid–base titration, the partition coefficients of aqueous two-phase systems(ATPs), and 1H nuclear magnetic resonance (1H-NMR). The results showed that the transphilic fractions separated by XAD-4 accounted for 11.09% of NOM, while the proportion increased to 20.33% with the method of NDAM fractionation. Besides, the hydrophilic components enriched by NDAM not only have more π-conjugated systems and more aromatic structure but also contain more oxygen-containing and nitrogen-containing functional groups. In addition, the hydrophilic fractions separated by NDAM contained more DBP precursors. The NDAM separates more NOM which can produce bromine-containing DBPs into HPIA, and the DBP productivity of HPIN is significantly higher than that of XAD-4. In general, the NOM fractionation method proposed in this study utilizing NDAM resin could fractionate the hydrophilic fractions in NOM more thoroughly, showing application potential in the analysis and control of DBPs formed from NOM.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Minjie Hou,Leiming Wang,Yanning Sun,Yanzhu Guo,Xueru Sheng,Fengshan Zhang,Haidong Sun,Pedram Fatehi,Haiqiang Shi
Generally, lignin separation from prehydrolysis liquor (PHL) is accompanied by sugar removal, making the purification of PHL challenging. However, how sugar loss from PHL can be minimized in PHL purification is still unclear. In this work, a method for removing lignin from PHL was attested, which included treatments of PHL with poly aluminum chloride (PAC), activated carbon, and XAD-4 resin. The results exhibited that the PAC could form complexation with lignin facilitating lignin removal from PHL. At the PAC concentration of 15 mg/L, 10% of lignin was removed, while no significant sugar loss was observed. Subsequently, by treating PHL with activated carbon, 87% of the remaining lignin was removed from the PHL, while sugar loss was identified to be 14%. XAD-4 resin treatment could slightly improve the lignin removal from 87% to 92%. However, the XAD-4 was unselective in sugar removal and led to an increased sugar loss (from 14% to 37%). Interestingly, removing colloidal lignin by PAC benefited the subsequent activated carbon process for improving lignin removal. In other words, PAC removed not only colloidal lignin but also facilities lignin isolation (i.e., an increase from 81% to 87%) and prohibited sugar loss (a drop from 27% to 6%) in the subsequent activated carbon treatment.
研究领域:
生物质转化
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制浆化学
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分离纯化
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碳水化合物化学
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环境工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2026
·
IF 5.1
Yin Pang,Zhuolin Qi,Lei Cao,Wei Qi,Junfeng Mao,Yukun Huang,Haifeng Cong,Xingang Li,Jiawei Wen
Dual-site modulated P204-P507/XAD-4 resin separates Pt/Co efficiently. • Alkaline activation of P-OH groups significantly boosts Co(II) capture. • HFIP effectively shields P=O sites to suppress Pt(IV) co-adsorption. • The Co/Pt separation factor achieves a nearly ten-fold improvement. • DFT and XPS reveal decoupled pathways via synergy-through-inhibition. The efficient recovery of platinum (Pt) and cobalt (Co) from spent proton exchange membrane fuel cell (PEMFC) catalysts is vital for the sustainable hydrogen economy, yet their deep separation from acidic leachates is hindered by the inherent affinity property of organophosphorus extractants. In this study, a dual-site regulation strategy was developed using a synergistic P204-P507/XAD-4 solvent-impregnated resin (SIR). By combining alkaline activation to enhance P–OH cation-exchange capacity (boosting Co(II) uptake from 40.19 ± 0.31 to 47.26 ± 0.58 mg/g at pH 7.0) as well as the hexafluoroisopropanol (HFIP) masking to selectively shield P=O sites via competitive hydrogen bonding (suppressing Pt(IV) adsorption from 7.60 ± 0.66 to 3.78 ± 0.47 mg/g at pH 3.0), the competing adsorption pathways were effectively decoupled. Experimental results showed that the dual-modified resin achieved a Co(II) adsorption capacity of 47.26 ± 0.58 mg/g and an exceptional separation factor (SF Co/Pt ) of 248.85 ± 10.19 at pH 7.0, representing an approximately ten-fold improvement over the unmodified composite. Mechanistic investigations via XPS and DFT calculations indicated that Co(II) is predominantly captured through P–OH sites, while the binding energy shifts in P=O groups are primarily attributed to a secondary inductive effect rather than direct coordination. Furthermore, in continuous fixed-bed operation, the resin exhibited a wide separation window with Co(II) breakthrough delayed to 55 bed volumes, delivering a Pt-enriched effluent with 99.1% purity at 97.0% recovery, while the retained Co(II) was quantitatively eluted at 96.6% purity. The resin also retained over 90% of its initial Co(II) adsorption efficiency after three consecutive adsorption–desorption cycles. and offering a mechanism-driven approach for precision metal adsorbent design.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）