Catalysis Science & Technology
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2023
·Vol. 13
·期 22
·6561-6569
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IF 5
Songlei Mo,Yong Guo,Xiaohui Liu,Yanqin Wang
The glycolysis of polyethylene terephthalate (PET) is considered as the most promising PET recycling strategy due to its mild reaction conditions and circularity. Herein, several metal-doped SBA-15 (M/SBA-15) as heterogeneous Lewis acid catalysts were investigated to screen the best catalyst and to understand the essence for their differences in PET glycolysis. It is found that the catalytic activity is positively correlated with the acid amount in different metal-doped SBA-15 and Ti/SBA-15 with different Ti loadings, with the exception of Nb/SBA-15. 4Ti/SBA-15 with abundant Lewis acid sites shows excellent PET glycolysis ability, with the yield of bis(2-hydroxyethyl) terephthalate (BHET) reaching 87.2% within 45 min at 190 °C (isolated yield 73%). While 4Nb/SBA-15 has a similar acid amount as that in 4Ti/SBA-15, but it has very low catalytic activity probably due to its strong oxygen affinity. Acetone–methanol-adsorption DRIFTS confirms its strong oxygen affinity, which would poison the acid sites by ethylene glycol (EG) and result in very low activity. This study demonstrates that PET glycolysis activity is really correlated with the amount of Lewis acid sites, but species with very strong oxygen affinity would lower its activity. Further diffuse reflection ultraviolet-visible (DR UV-vis) spectra analysis confirms that tetrahedral Ti4+ species in Ti/SBA-15 is the real active center. In addition, 4Ti/SBA-15 has good reusability and can be used in common real PET (dyed polyester fabric, PET bottles) glycolysis. These results indicate that increasing the amount of Lewis acid sites is a promising way to enhance PET glycolysis and 4Ti/SBA-15 with high activity and stability is a potential catalyst for industrial application.
研究领域:
材料科学
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催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
·
2012
·
IF 2.947
Hui-xue Ren,Han-jie Ying,Ping-kai Ouyang,Ping Xu,Jing Liu
Efficient and pollution-free catalysts play an essential role in the ultimate biodegradation of products in the synthesis of biodegradable and recyclable poly( l -lactic acid) (PLLA). Therefore, macroporous resin was utilized as the solid acid for the first time, on which lactate that could be absorbed in vivo was composited to catalyze the synthesis of PLLA. It was discovered that macroporous resin Amberlyst-15 showed good catalytic activity in oligomerization and polymerization, and lactate showed different catalytic efficiencies due to the differences in ionic radius and ionic charge. Compared to the traditional catalysts of SnCl 2 ·2H 2 O/TSA, the composite catalyst can improve the quality, yield and optical purity of its product, which can also be recycled without any residual in products. PLLA with molar mass of about 110,000 g mol −1 was synthesized at the yield of 93%. The product exhibits pure color (white), and its optical purity and crystallinity are 98% and 55%, respectively. A possible catalytic mechanism was proposed. The resulting PLLA products were characterized by GPC, 1 H NMR, DSC, and polarimeter.
研究领域:
材料科学
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生物工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2018
·
IF 3.649
Manman Jin,Jinkai Wang,Bing Wang,Zhenmei Guo,Zhiguo Lv
A simple and eco-friendly approach for green oxidation of aldehydes has been proposed, which employed highly efficient heterogeneous catalysts tungsten-doped modified silica SBA-15 (W-SBA-15) as catalysts and H 2 O 2 as a green oxidant. W-SBA-15 were synthesized by immobilizing tungsten species on modified SBA-15 and first used in the aldehydes oxidation reaction. W-SBA-15-APTS (0.002 g, APTS, a kind of modifier) displayed an equivalent catalytic activity comparable to that of homogenous catalyst (H 2 WO 4 , 0.5 g) and maintained excellent catalytic activity over 20 cycles. The pore diameter, ca . 7.94–9.14 nm, of W-SBA-15 provides a suitable mesoscopic environment for the substrate, and the product can diffuse freely during the oxidation of glutaraldehyde (GA). Effective but different catalytic performance of W-SBA-15 for the oxidation of other aldehydes suggests the universal applicability of W-SBA-15. The possible mechanism of the oxidation state of tungsten species in W-SBA-15-APTS was proposed; tungsten species are not only attached to APTS but also incorporated into the framework of SBA-15.
研究领域:
化学
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环境科学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Xiao Dan Sun,Zhangxin Duan,Jingjing Song,Hanxing Yang,Kai Yan,Zhenhua Tian,Dangge Gao,Jianzhong Ma
Carcinogen Cr(VI) is reduced efficiently into Cr(III) by a photocatalyst, but the produced Cr(III) is difficult to transfer from the photocatalytic active site. The “two birds with one stone” strategy is proposed to realize the in situ growth of ZnIn2S4 nanoplates on SBA-15 and the creation of separated active sites, in which ZnO loading on the porous SBA-15 nanorod was used as a zinc source. Obtained samples ZnIn2S4/SBA-15 (ZIS/SBA) showed the redshift of the absorption band and better separation of photoinduced carriers than pristine ZnIn2S4, due to its smaller size and S defect. All of the Cr(VI) was reduced to Cr(III) by the ZIS/SBA sample during the photocatalytic process, which was 2 times higher than pristine ZnIn2S4. Moreover, 92.8% of Cr(III) was adsorbed simultaneously during photocatalysis due to the electrostatic interaction from SBA-15. In addition, the ZIS/SBA sample showed good recycling stability after 5 times cycles, providing a new strategy for the in situ growth of ZnIn2S4 on the surface of porous materials and a novel way for the simultaneous removal of Cr(VI) and Cr(III) during photocatalysis.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2018
·Vol. 10
·期 47
·22348-22356
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IF 7.233
Xusheng Cheng,Dongxu Wang,Jiancong Liu,Xin Kang,Haijing Yan,Aiping Wu,Ying Gu,Chungui Tian,Honggang Fu
Decreasing Pd usage whilst maintaining a superior performance is promising, but remains a challenge in the catalytic field. Herein, we have demonstrated the highly efficient promotion of Mo2N with a reduced amount of Pd for the liquid-phase hydrogenation reaction. The Mo2N (2–3 nm) was uniformly anchored onto mesoporous SBA-15 by using PMo12 as the Mo source. The small size and good dispersion of Mo2N is favourable for allowing their effective contact with post-loading Pd. This good contact is conducive to developing a synergistic catalyst, which was verified by studying the liquid-phase hydrogenation of p-nitrophenol (PNP) to p-aminophenol (PAP) with NaBH4 as the H source. The conversion ability of PNP to PAP on 1 wt% Pd–Mo2N/SBA-15 was vastly superior to 1 wt% Pd/SBA-15 and even better than 20 wt% Pd/SBA-15. The low-Pd, highly efficient catalysis is ascribed to the transfer of the electrons from Mo2N to Pd for the easy activation of H. The synergy can be affected by the type of support used. SBA-15 is superior to SiO2 and the other supports, which could be related to the large surface area and the plentiful number of pores on SBA-15, which is favourable to the dispersion of Pd and Mo2N, and the transfer/diffusion of the reactants. In particular, a highly efficient catalyst can be achieved at an even more reduced Pd loading (0.05 wt%). The current method describes the design of a highly efficient catalyst for the hydrogenation reaction using low amounts of noble metals.
研究领域:
催化化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
CATALYSIS LETTERS
·
2019
·Vol. 149
·期 11
·2994-2999
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IF 2.372
Zhang Shengnan,Wang Hongmei,Cang Ruibai,Lu Bin,Zhao Jingxiang,Cai Qinghai
Abstract A composite material (FeSIL) prepared by FeCl 3 -imidazolium ionic liquid grafted on SBA-15 exhibited effective catalytic activity for solvent-free oxidation of styrene into benzaldehyde with high selectivity using H 2 O 2 oxidant and it presented easy recovery and reusability. In situ DRIFTS spectra for styrene and H 2 O 2 adsorption showed that an intermediate Fe 3+ –π surface complex on the catalyst surface was responsible for the activation of styrene and its reaction with H 2 O 2 molecules on the surface or in the bulk phase. Graphic Abstract Iron-chloride immobilized ionic liquid (FeSIL) was prepared by N -methylimidazole reacting with chloropropylsilane grafted on SBA-15 and coordinating of FeCl 3 to the imidazolium on the surface. The higher catalytic activity of the catalyst for effective oxidation of styrene under solvent-free condition were achieved The catalyst can be easily recovered and effectively reused without a significant loss in its activity.
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
INORGANIC CHEMISTRY
·
2023
·
IF 4.6
Encheng Liu,Zhenzhen Wang,Zhonghua Sun,Zhihui Zhang,Mingyang He,Qun Chen,Junfeng Qian
The chemical microenvironment modulation of active sites holds promise for facilitating their catalytic performance. Herein, single-atom Ru anchored by ZrSBA-15 modified with diverse organic amine groups has been fabricated and enabled CO2 hydrogenation to produce formic acid (FA) under mild conditions. However, the reaction cannot be achieved without the modification of organic amines. The functional groups as the microenvironment around Ru active sites effectively regulated the activity, in which Ru encapsulated in ZrSBA-15 bearing –NH2 groups exhibited the highest activity, with turnover number (TON) and turnover frequency (TOF) values of 505 and 64 h–1, respectively. Both characterization and experimental results validated that the functional group manipulated the adsorption capacity of the reactant, the electronic state of Ru and hydrophilicity/hydrophobicity of the materials, and thus the catalytic performance.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Qiang Gao,Jin-Feng Xie,Ya-Ting Shao,Chao Chen,Bo Han,Kai-Sheng Xia,Cheng-Gang Zhou
The development of rare earth adsorbent with high adsorption capacity and rapid adsorption rate is one of the most important issues for enriching and recovering rare earth ions. In the present work, an inorganic phosphorous acid-modified mesoporous SBA-15 (P-SBA-15) was facilely synthesized by a simple and cost-effective post-grafting approach, and its adsorption behavior towards the rare earth ion Gd(III) was investigated. Benefiting from high specific surface area (669.7 m 2 ·g −1 ), large pore size (9.1 nm), and the presence of abundant phosphorous acid groups (1.4 mmol·g −1 ) on the surface, the P-SBA-15 exhibited an excellent performance in terms of capacity and kinetics on adsorption of Gd(III). Under optimized conditions, the adsorption capacity of P-SBA-15 towards Gd(III) was up to 1.3 mmol·g −1 at 30 °C, which is the second highest value as compared with previously reported Gd(III) adsorbents. Moreover, the adsorption of Gd(III) onto P-SBA-15 was ultrafast, achieving adsorption equilibrium within only 2 min. Test of reusability revealed that this mesoporous adsorbent could be repeatedly used several times without significant loss in binding capacity. This work not only provides a new insight into the fabrication of phosphorous acid-functionalized mesoporous silica, but also demonstrates its prospective application in adsorptive removal and/or recovery of rare earth ions.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2019
·
IF 4.182
Lixue Gai,Lin Guo,Qingda An,Zuoyi Xiao,Shangru Zhai,Zhongcheng Li
Functionalized SBA-15 has attracted considerable interest owing to its highly ordered mesoporous structure, well thermal stability and great potential applications. Meanwhile, as was demonstrated, polypyrrole (PPy) with good electrical conductivity is also a very popular absorber-related candidate. Herein, long-rod shape SBA-15/PPy-X composites were successfully synthesized via a simple hydrothermal treatment by combining in situ chemical oxidative polymerization method. The SBA-15/PPy-X composites exhibited effective absorption band (RL < −10 dB) and electromagnetic wave absorption capacities in comparison with the pristine SBA-15 sample, which were pertinent to the properties of strong dielectric loss and better impedance matching, implying enhanced dielectric properties by modifying with suitable amount of PPy species. The minimum reflection loss (RL) of SBA-15/PPy-0.5 composites reached −44.7 dB with a very low filler loading (15 wt%), corresponding to the thickness of 3.5 mm at 8.9 GHz. Besides, the effective absorption bandwidth was up to 6.1 GHz (11.1–17.2 GHz) and 3.8 GHz (7.4–11.2 GHz) with the thickness of 2.5 mm and 3.5 mm, respectively, which can cover most of the Ku-band (12–18 GHz) and X-band (8–12 GHz). The results indicated that the newly designed silica-based SBA-15/PPy-X composites can be promising EMW absorbers with an excellent performance at a target frequency (typical radar channels).
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Xianxiang Liu,Jiafu Xiao,Hui Ding,Wenzhou Zhong,Qiong Xu,Shengpei Su,Dulin Yin
Amino modified SBA-15 (SBA-NH 2 ) was used to immobilize vanadyl (VO 2+ ) and cupric (Cu 2+ ) ions, giving SBA-NH 2 -VO 2+ and SBA-NH 2 -Cu 2+ catalysts, respectively, and the as-prepared catalysts were characterized by XRD, XPS, TEM and Nitrogen adsorption–desorption technologies. The catalytic performance of the SBA-NH 2 -VO 2+ catalysts for the oxidation of HMF can be enhanced by the use of SBA-NH 2 -Cu 2+ as the co-catalyst. Several important reaction parameters were investigated, and it was found that the reaction solvent showed a great effect on the oxidation of HMF. The highest HMF conversion and product selectivity were obtained in aromatic solvents. The highest HMF conversion reached 98.8% at 110 °C in 4-chlorotoluene, affording DFF and 2,5-furandicarboxylic acid (FDCA) with yields of 28.9% and 62.7%, respectively. More importantly, the catalysts could be recycled and showed no significant decrease of their catalytic activities.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2014
·
IF 3.916
Guozhi Fan,Chongjing Liao,Tao Fang,Shanshan Luo,Guangsen Song
The acetylation of cellulose using sulfonated Amberlyst 15 as a new and reusable catalyst was investigated. Optimization of the acetylation process was carried out by variation in the amount of added catalyst, acetic acid, and acetic anhydride as well as the reaction conditions, which includes reaction time and reaction medium. Cellulose acetate, with a degree of substitution (DS) value of 2.38 and yield of 54.1%, was obtained under the optimized conditions and characterized using Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis–derivative thermogravimetry (TGA–DTG), and differential scanning calorimetry (DSC). The sulfonated polymer catalyst could be easily recovered by centrifugation after acetylation. Both the fresh and recovered catalysts were characterized by means of FTIR, TGA–DTG, DSC, and scanning electron microscopy (SEM), and the recovered catalyst could be successfully reused without further treatment. It was found that Amberlyst 15 possessed excellent catalytic stability, no significant changes in the DS values, and consistent yields of cellulose acetate observed over four reaction cycles.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2022
·Vol. 12
·期 11
·1334
·
IF 4.501
Fujian Lv,Yingchun Miao,Didi Yang,Bing Mao,Zhenfeng Bian,Fengxia Zhu
The adsorption-enhancing TiO2-SBA-15 photocatalyst has been synthesized by an in situ etching displacement method, which possesses unique regular hexagonal pores and large specific surface area. The as-prepared TiO2-SBA-15 can effectively adsorb and increase the concentration of pollutants in the photocatalyst and collision likelihood with the photogenerated radicals, thus improving the efficiency of photocatalytic organic degradation. The structure and morphology have been characterized by N2adsorption isotherms, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), and scanning electron microscopy (SEM). These characterizations confirm that TiF4alcohol solution prefers to react with the internal surface of SBA-15 because of the Siphon effect. Fourier transform infrared (FTIR) spectra demonstrate that a Ti-O-Si bond formed after the reaction of TiF4with SBA-15, which reveals a wonderful combination of TiO2and SiO2even at low temperatures. Through this function, the nanocomposite TiO2-SBA-15 could obviously improve the efficiency of photocatalytical removal of toluene in the gas phase.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）