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Chinese Journal of Catalysis
2015, Vol. 36, No. 10
Online: 26 September 2015


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Deng and co-workers in their Article on pages 1750–1758 reported the structure modification of Ir-Re alloy catalysts. The bifunctional mechanism of glycerol hydrogenolysis over Ir-Re alloy is verified by the experimental results. Hence the catalytic activity of Ir-Re alloy could be enhanced by increasing the amount of acidic Re-OH sites.

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Table of Contents for VOL.36 No.10 2015, 36 (10):  0-0.  Abstract ( 138 )   PDF (1744KB) ( 661 )

Perspective

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Elementary processes in photocatalysis of methanol and water on rutile TiO2(110): A new picture of photocatalysis Qing Guo, Timothy K. Minton, Xueming Yang 2015, 36 (10):  1649-1655.  DOI: 10.1016/S1872-2067(15)60935-4 Abstract ( 337 )   [Full Text(HTML)] () PDF (886KB) ( 705 )

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Spin catalysts: A quantum trigger for chemical reactions Oleksiy V. Khavryuchenko, Volodymyr D. Khavryuchenko, Dangsheng Su 2015, 36 (10):  1656-1661.  DOI: 10.1016/S1872-2067(15)60948-2 Abstract ( 845 )   [Full Text(HTML)] () PDF (576KB) ( 1146 )   Spin catalysis allows restrictions of the spin conservation rule to be overcome, and, moreover, provides a tool for fine control of elementary reactions. Spin-conductive solid catalysts make processes over surfaces strongly correlated and also can trigger the direction of the reaction via external magnetic field application. Activation/deactivation of O2 and non-polar small molecules, homolytic bond cleavage, and coupling of radicals are within the practical scope of spin catalysis.

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Microstructure of rapidly quenched Ni-Al based catalysts by advanced electron microscopy Bingsen Zhang, Aiguo Zheng, Xiaoli Pan, Yiming Niu, Xiaoxin Zhang, Dangsheng Su, Baoning Zong 2015, 36 (10):  1662-1667.  DOI: 10.1016/S1872-2067(15)60925-1 Abstract ( 198 )   [Full Text(HTML)] () PDF (1596KB) ( 589 )   The microstructure of air-sensitive Raney-type catalysts directly determines their activity and selectivity for a catalytic reaction. The fine structure of a rapidly quenched Ni-Al alloy doped with Fe and Cr (RQ Ni-Al-FC) was investigated by electron microscopy imaging and spectroscopic techniques, and its structure was successfully characterized by using a vacuum transfer holder in the transmission electron microscope. The microstructural comparison of pristine and passivated/combusted samples was discussed in detail. This work provides the structure of RQ Ni-Al based catalysts as a contribution to exploring their synthesis-structure-performance relationship.

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Recyclable Sn-TiO2/polythiophene nanohybrid material for degradation of organic pollutants under visible-light irradiation M. Ravi Chandra, T. Siva Rao, B. Sreedhar 2015, 36 (10):  1668-1678.  DOI: 10.1016/S1872-2067(15)60944-5 Abstract ( 337 )   [Full Text(HTML)] () PDF (1047KB) ( 743 )   A Sn-doped TiO2/polythiophene nanohybrid (SPNH) was synthesized by a modified sol-gel process at low temperature. The prepared catalyst was characterized by X-ray diffraction (XRD), infrared (IR) spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-Vis) diffuse reflectance spectrophotometry (UV-DRS), and Brunauer-Emmett-Teller surface area analysis. The XRD results confirmed that polythiophene (PTh) had no effect on the crystal structure of TiO2. IR spectra and UV-DRS indicated that an interaction occurs between the interface of PTh and metal oxide in SPNH, and doped metal oxide nanoparticles were incorporated into PTh to form a core-shell structure. XPS analysis confirmed the presence of Sn4+ and respective elements of PTh and TiO2 in SPNH. SPNH displayed higher adsorption capacities for pollutants than Sn-doped TiO2 nanoparticles (STN). In addition, SPNH exhibited higher photocatalytic activity and stability than STN towards the degradation of organic pollutants nitrobenzene (NB) and malachite green (MG) under visible-light irradiation. Because of the presence of PTh on STN, there was an increase in the adsorption of NB (24%) and MG (21%) on the surface of SPNH, which led to a higher photocatalytic yield. The recyclability of the photocatalytic activity for the photocatalyst was examined by about five runs and not found any depletion or degradation of PTh under visible light irradiation. The high photocatalytic activity of SPNH makes it an attractive candidate as a photocatalyst for industrial water purification.

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Influence of synthesis conditions on physical properties of lanthanide-doped titania for photocatalytic decomposition of metazachlor Marcela Kralova, Irina Levchuk, Vit Kasparek, Mika Sillanpaa, Jaroslav Cihlar 2015, 36 (10):  1679-1685.  DOI: 10.1016/S1872-2067(15)60943-3 Abstract ( 296 )   [Full Text(HTML)] () PDF (1012KB) ( 759 )   Heterogeneous photocatalysis is a very effective method for the decomposition of a whole range of water pollutants. In this work, the influence of synthesis conditions on the physical properties and photocatalytic activity of lanthanide-doped titanium dioxide photocatalysts was evaluated. Titanium dioxide was prepared via sol-gel synthesis followed by a solid state reaction under different conditions, including different temperatures (450, 550, and 650 ℃) and reaction times (4, 8, and 12 h). The crystalline phase of the products was determined to be solely anatase using X-ray diffraction, and this result was confirmed by Raman spectroscopy. The structure, as well as particle size, of the samples was examined using scanning electron microscopy, and their specific surface area was calculated using Brunauer-Emmett-Teller analysis. The band gap energy of the samples was examined using ultraviolet-visible spectroscopy from diffuse reflectance measurements. Doping with lanthanide species, dysprosium and praseodymium, caused the absorption edge to shift towards higher wavelengths and enhanced photocatalytic activity in comparison with pure titania. The photocatalytic activity of the samples was studied in terms of the degradation of the commonly used herbicide metazachlor. The decomposition was carried under UV light and the decrease in metazachlor concentration was measured using high performance liquid chromatography. The best performance was obtained for samples treated at 550 ℃ for 8 h during the solid state reaction step.

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High performance Pd catalysts supported on bimodal mesopore silica for the catalytic oxidation of toluene Nanli Qiao, Yang Li, Na Li, Xin Zhang, Jie Cheng, Zhengping Hao 2015, 36 (10):  1686-1693.  DOI: 10.1016/S1872-2067(15)60924-X Abstract ( 406 )   [Full Text(HTML)] () PDF (1310KB) ( 727 )   A series of bimodal mesoporous silica (BMS-x)-supported Pd catalysts were successfully prepared by a facile sol-gel approach, followed by an impregnation method. The synthesized catalysts were characterized by several analytical techniques and the oxidation of toluene was used to evaluate their catalytic performance. Textural analysis showed that all samples had high surface areas (~1000 m2/g), large pore volumes (~1.2 cm3/g) and uniform mesopore size (~2.6 nm). Defining the level of ammonia solution to within a certain range resulted in the catalysts possessing a typical bimodal mesoporous structure with an intraparticle framework mesopore and an interparticle textural mesopore (18-40 nm). Transmission electron microscopy observations and CO chemisorption results revealed that this unique bimodal mesoporous structure helped to decrease the particle size of Pd nanoparticles and could further enhance their dispersion. Activity tests revealed the Pd/BMS-5-Pd/BMS-20 catalysts with a bimodal mesopore structure possessed superior catalytic performance for the oxidation of toluene compared to Pd/BMS-30 with a unimodal mesopore structure. More importantly, compared with the Pd/MCM-41 and Pd/MCM-48 catalysts, Pd/BMS-15 had improved hydrothermal stability and catalytic performance at a high gas hourly space velocity of 70000 h-1. These results indicate the potential application of the catalysts for the elimination of volatile organic compounds.

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Catalytic conversion of Jerusalem artichoke tuber into hexitols using the bifunctional catalyst Ru/(AC-SO3H) Likun Zhou, Zhenlei Li, Jifeng Pang, Mingyuan Zheng, Aiqin Wang, Tao Zhang 2015, 36 (10):  1694-1700.  DOI: 10.1016/S1872-2067(15)60933-0 Abstract ( 267 )   [Full Text(HTML)] () PDF (759KB) ( 613 )   Jerusalem artichoke tuber (JAT) was employed as a feedstock for production of hexitols under mild conditions over a sulfonated activated carbon supported Ru catalyst (Ru/(AC-SO3H)). In comparison with conventional Ru/AC catalyst, the sulfonation process of the carbon support was observed to create abundant surface acid groups, which in turn function as the anchoring sites for Ru nanoparticles, thus increasing the dispersion of Ru. Consequently, the bifunctional Ru/(AC-SO3H) catalyst displayed significantly enhanced activity in one-pot production of hexitols from JAT; the hexitols yield achieved 92.6% over the 3%Ru/(AC-SO3H) catalyst when the reaction was conducted at 373 K and 6 MPa H2 for 3 h. The stability of the catalyst was also investigated, which showed a decreasing trend in the yield of sorbitol with the run number due to poisoning of Ru surface by the impurity in the JAT feedstock. In contrast, when pure inulin was used as the feedstock, the catalyst presented excellent stability in the successive four runs.

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Characterization and activity of V2O5-CeO2/TiO2-ZrO2 catalysts for NH3-selective catalytic reduction of NOx Yaping Zhang, Wanqiu Guo, Longfei Wang, Min Song, Linjun Yang, Kai Shen, Haitao Xu, Changcheng Zhou 2015, 36 (10):  1701-1710.  DOI: 10.1016/S1872-2067(14)60916-0 Abstract ( 348 )   [Full Text(HTML)] () PDF (858KB) ( 1200 )   A series of V2O5-xCeO2/TiO2-ZrO2 (Ti-Zr) catalysts with different CeO2 loadings (x = molar ratio of Ce/Ti-Zr) were prepared, and their catalytic performance for the selective catalytic reduction (SCR) of NOx by NH3 was investigated in the presence of SO2 and H2O. The physicochemical properties of the catalysts were characterized by N2 sorption analysis, high-resolution transmission electron microscopy, X-ray diffraction, H2-temperature-programmed reduction, NH3-temperature- programmed desorption, and in situ diffuse reflectance infrared Fourier transform spectroscopy. The presence of CeO2 in the catalysts led to higher conversion of NOx within a wider operating temperature range. V2O5-xCeO2/Ti-Zr catalyst (x = 0.2) exhibited the highest activity. Higher loadings of CeO2 adversely affected the NOx conversion at higher temperatures. The characterization results revealed that CeO2 was amorphous and highly dispersed over the Ti-Zr support. The catalysts featured single-crystal electron diffraction features. The presence of CeO2 significantly increased the reduction ability of the catalysts, and low V2O5 loadings were beneficial to the low-temperature SCR. V2O5/TiO2 catalyst exhibited medium-to-strong and strong acid desorption of NH3, whereas V2O5/Ti-Zr featured weak acid sites onto which desorption of NH3 occurred. The presence of CeO2 could increase the amount of both the Brönsted and Lewis acid sites, which were expected to play a key role in the excellent SCR activity. In contrast, the presence of V2O5 reduced the amount of Brönsted acid sites. All V2O5-CeO2/Ti-Zr catalysts exhibited poor stability and weak resistance to H2O poisoning but high resistance to SO2. However, the original catalytic activity of V2O5-xCeO2/Ti-Zr (x = 0.3) could be fully restored following poisoning with SO2 and H2O. For the poisoned catalysts, the formation of Ce(SO4)2 led to the decreased catalytic performance at the intermediate temperatures, which increased at the higher temperatures because of the presence of V2O5.

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Preparation of mesoporous Fe-Cu mixed metal oxide nanopowder as active and stable catalyst for low-temperature CO oxidation Ehsan Amini, Mehran Rezaei 2015, 36 (10):  1711-1718.  DOI: 10.1016/S1872-2067(15)60922-6 Abstract ( 296 )   [Full Text(HTML)] () PDF (935KB) ( 741 )   A series of mesoporous Fe-Cu mixed metal oxide nanopowders with different Cu/Fe molar ratios and high specific surface areas were synthesized via a simple, inexpensive, surfactant-free sol-gel route using propylene oxide as the gelation agent. The catalytic behavior of the nanopowders in low-temperature CO oxidation was investigated using a microreactor-gas chromatography system. The prepared materials were characterized by X-ray diffraction, N2 adsorption-desorption, thermogravimetric-differential thermal analysis, temperature-programmed reduction, Fourier transform infrared spectroscopy, and transmission electron microscopy. These mesoporous Fe-Cu mixed metal oxide catalysts had nanocrystalline structures, narrow pore size distributions, and high surface areas; they showed high catalytic activities and stabilities in low-temperature CO oxidation. The addition of CuO to iron oxide affected the structure and catalytic performance of the iron oxide. The catalyst containing 15 mol% CuO had the highest specific surface area and catalytic activity, and showed high catalytic stability in low-temperature CO oxidation.

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Host (dealuminated Y zeolite)-guest (trinuclear metal clusters of Co, Mn and Cox/Mny) as nanocomposite catalysts for the epoxidation of cyclohexene Maryam Moosavifar, Alieh Navid Arbat, Zolfaghar Rezvani, Kamellia Nejati 2015, 36 (10):  1719-1725.  DOI: 10.1016/S1872-2067(15)60908-1 Abstract ( 313 )   [Full Text(HTML)] () PDF (764KB) ( 391 )   Trinuclear metal clusters of Co, Mn and mixtures of Co/Mn including [Mn3(O)(CH3COO)6-(py)3]-Y, [Co3(O)(CH3COO)6-(py)3], [Co2Mn(O)(CH3COO)6-(py)3]-Y and [CoMn2(O)(CH3COO)6-(py)3]-Y] were prepared inside the nanocage of dealuminated Y zeolite by the template synthesis method. These catalysts were characterized by Fourier transform infrared, Ultraviolet-visible, field scanning electron microscopy, X-ray diffraction and atomic absorption spectroscopy. The encapsulated metal clusters showed good catalytic activity in the epoxidation of cyclohexene with H2O2/O2. Epoxide yields were 82.5% to 90.7%. NaBr was used as a promoter for the oxidation. The homonuclear metal clusters showed higher catalytic activity than the others and the highest efficiency was with the Mn3(O)-DAZY compound. The catalytic activity order was Mn3(O)-DAZY > Co3(O)-DAZY > Mn2Co(O)-DAZY > MnCo2(O)-DAZY.

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Free radical mechanism investigation of the side-chain alkylation of toluene with methanol on basic zeolites X Huanhui Chen, Xiaoci Li, Guoqing Zhao, Hongbo Gu, Zhirong Zhu 2015, 36 (10):  1726-1732.  DOI: 10.1016/S1872-2067(15)60896-8 Abstract ( 340 )   [Full Text(HTML)] () PDF (576KB) ( 815 )   The side-chain alkylation of toluene represents a novel, environmentally friendly, and low cost route for the production of styrene. However, the yield of styrene produced in this way is currently low, and the mechanism responsible for the side-chain alkylation of toluene is poorly understood. Furthermore, the reason for the higher catalytic efficiency of CsX over NaX and KX remains unclear. In this work, the free radical mechanism of the side-chain alkylation of toluene over basic zeolite X has been elucidated using quantum chemical calculations, together with isotope tracing experiments and the reaction between p-nitrotoluene and methanol. The adsorption isotherm of methanol showed that Cs+ ions could block methanol from accessing the β-cage, which is where the side-chain alkylation reaction occurred. Furthermore, the H-D exchange results between toluene and deuterated toluene (C6D5CD3) showed that CsX was more efficient as a catalyst than KX for the conversion of toluene to the corresponding benzyl radical (C6H5CH2·). These two results therefore explain the higher catalytic activity of CsX towards side-chain alkylation than KX. Based on the free radical mechanism, the selectivity of styrene could be increased from 17.4% to 59.4% using CO2 as carrier gas instead of N2.

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Structures and vibrational spectra of Ti-MWW zeolite upon adsorption of H2O and NH3: A density functional theory study Yiming Qiao, Zhilin Fan, Yanjiao Jiang, Na Li, Hao Dong, Ning He, Danhong Zhou 2015, 36 (10):  1733-1741.  DOI: 10.1016/S1872-2067(15)60900-7 Abstract ( 259 )   [Full Text(HTML)] () PDF (944KB) ( 751 )   The structures and vibrational spectroscopic features of framework Ti(IV) species in Ti-MWW zeolite upon adsorption of H2O and NH3 were investigated by density functional theory. The calculations were carried out on cluster models up to 36 tetrahedra at the B3LYP/6-31G(d,p) level of theory. The calculated results indicate that both Ti(OSi)4 and Ti(OSi)3OH species can interact with H2O or NH3 molecules to form five-coordinated complexes. The Ti(OSi)3OH species has higher Lewis acidity and adsorbs the ligands more easily than Ti(OSi)4. The Ti-specific band is attributed to the collective vibration of the antisymmetric stretching of Ti-O-Si bonds. The vibrational frequencies of coordinated Ti species can be divided into two regions: the Ti-specific vibration region and the hydroxyl group vibration region. After adsorption of H2O, the Ti-specific band of the Ti(OSi)4 species shifted from 960 to 970 cm-1, and the Ti-specific bands of the Ti(OSi)3OH species shifted from 990 cm-1 (T1 site) and 970 cm-1 (T3 site) to 980 cm-1. The frequencies of the corresponding NH3 adducts were about 5 cm-1 higher. The Ti(OSi)3OH species can also form hydrogen bonded complexes with H2O and NH3 through Ti-OH, resulting in the hydroxyl stretching band of Ti-OH red shifting by 500-1100 cm-1 and appearing in the 2700-3200 cm-1 region.

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Effects of Br substituent on catalytic performance of Ru-bda (H2bda = 2,2'-bipyridine-6,6'-dicarboxylic acid) catalysts for water oxidation Zhao Liu, Yan Gao, Ze Yu, Min Zhang, Jianhui Liu 2015, 36 (10):  1742-1749.  DOI: 10.1016/S1872-2067(15)60895-6 Abstract ( 348 )   [Full Text(HTML)] () PDF (740KB) ( 780 )   A series of new Ru-bda catalysts with Br modification on the equatorial ligand, [Ru(Ln)(picoline)2] (H2L1 = 4-Br-2,2'-bipyridine-6,6'-dicarboxylic acid (4-Br-bda), 2; H2L2 = 4,4'-diBr-bda, 3) and [Ru(L1)(isoquinoline)2] 5, were synthesized for catalytic water oxidation. Compared with the un-substituted catalysts, the catalysts modified with Br displayed a marked change in the catalytic activities and reaction orders. The results confirm that the electronic effect of Br has a large effect on the kinetics and leads to the change in reaction orders.

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Effects of pretreatment temperature on bimetallic Ir-Re catalysts for glycerol hydrogenolysis Chenghao Deng, Li Leng, Jinghong Zhou, Xinggui Zhou, Weikang Yuan 2015, 36 (10):  1750-1758.  DOI: 10.1016/S1872-2067(15)60899-3 Abstract ( 288 )   [Full Text(HTML)] () PDF (1143KB) ( 601 )   A series of bimetallic Ir-Re/KIT-6 catalysts was prepared by direct activation of impregnated samples at various reduction temperatures to study the effect of pretreatment temperature on catalyst structure and on catalytic performance for glycerol hydrogenolysis. All catalysts were characterized by N2 adsorption-desorption, transmission electron microscopy, CO chemisorption, in-situ CO adsorption diffuse reflectance infrared Fourier transform spectroscopy and temperature-programmed desorption of ammonia (NH3-TPD). The results demonstrated that those catalysts reduced at 400 to 700 ℃ exhibited an Ir-Re alloy structure with similar particle sizes and Ir dispersions. Furthermore, NH3-TPD results indicated that all catalysts had similar acid strengths, though acid density varied with the reduction temperature. Increasing the pretreatment temperature from 400 to 600 ℃ monotonically increased the acid density of the catalysts and also improved the catalytic activity for glycerol hydrogenolysis. Reducing the Ir-Re alloy catalyst at 700 ℃ slightly decreased the activity due to the growth of the metal particles. Moreover, a linear relationship was identified between the acid density of a catalyst and its activity, verifying the vital roles of both Re and surface acidity with regard to optimizing the performance of Ir-Re alloy catalysts.

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Transesterification of glycerol with dimethyl carbonate over calcined Ca-Al hydrocalumite Liping Zheng, Shuixin Xia, Xiuyang Lu, Zhaoyin Hou 2015, 36 (10):  1759-1765.  DOI: 10.1016/S1872-2067(15)60915-9 Abstract ( 366 )   [Full Text(HTML)] () PDF (1777KB) ( 1144 )   A series of Ca-Al hydrocalumite with different Ca/Al ratios (1-6) were synthesized and used in the transesterification of glycerol with dimethyl carbonate (DMC) to glycerol carbonate (GC) under mild conditions. The calcined Ca-Al hydrocalumites were active with a selectivity toward GC that reached 97% at 93% conversion of glycerol over the sample with Ca/Al = 2 at 70 ℃, 3 h, and DMC/glycerol = 3. The glycerol conversion depended mainly on the proportion of strong basic sites in the calcined Ca-Al catalysts. The Ca12Al14O33 phase in the calcined catalysts was stable, but CaO was lost in recycle experiments and thus brought deactivation.

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CTAB modification of MCM-49 zeolite containing HMI and its acylation of anisole Huijuan Wei, Sujuan Xie, Kefeng Liu, Wenjie Xin, Xiujie Li, Shanhe Liu, Shunming Gu, Shenglin Liu, Longya Xu 2015, 36 (10):  1766-1776.  DOI: 10.1016/S1872-2067(15)60887-7 Abstract ( 292 )   [Full Text(HTML)] () PDF (731KB) ( 887 )   A series of MCM-49 zeolite catalysts containing different amounts of the hexamethyleneimine (HMI) template were calcined at different temperatures, and then modified with cetyltrimethylammonium bromide (CTAB). Changes in structural and acidic properties were investigated by XRD, N2 adsorption, NH3-TPD, adsorbed pyridine infrared and DRIFTS measurements, and 29Si and 27Al MAS NMR. There were cleaning off of amorphous particles and extraframework Al atoms inserted into the framework of the zeolite due to the CTAB modification. These two effects resulted in more framework Al in the CTAB modified samples than the untreated samples, and a higher Brönsted acid concentration, which was confirmed by the acylation of anisole with acetic anhydride. The catalytic roles of the acid sites located in the different pore systems in the zeolite were investigated. It was verified that the active sites after CTAB modification were mainly in the HMI-free regions.

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High-temperature Shilov-type methane conversion reaction: Mechanistic and kinetic studies Shujuan Kang, Qisheng Ma, Weiqun Chen, Guanyi Chen, Yongchun Tang 2015, 36 (10):  1777-1784.  DOI: 10.1016/S1872-2067(15)60966-4 Abstract ( 330 )   [Full Text(HTML)] () PDF (521KB) ( 598 )   Traditional Shilov reactions (performed in aqueous solution with a PtCl2 catalyst) for methane conversion suffer from catalyst deactivation at high temperatures (> 100 ℃), therefore only very low conversion rates have been achieved. In this paper, we show that Shilov-type C-H activations are achievable at much higher temperatures (~200 ℃) by addition of concentrated aqueous solutions of Cl- to inhibit Pt catalyst precipitation. Various chloride-based ionic liquids also stabilized the Pt catalyst at mild reaction temperatures (~140 ℃). Under high-pressure conditions (> 25.5 MPa), achieved using a specially designed sealed gold-tube reactor, very high methane conversion rates (> 90%) were obtained; this is attributed to the improved methane solubility in aqueous solution. Deuterium isotope (H/D) exchange between methane and water was used to examine the reaction reactivity and selectivity. Multiply D-substituted products were observed, indicating that multiple C-H activations occurred. A comprehensive network reaction that included all the chain reactions was set up to clarify the reactivities and product selectivities of the methane activation reactions. The reaction network consisted of a series of parallel first-order reactions, which can be described by the Arrhenius equation. The kinetic parameters such as the frequency factor, activation energies, and stoichiometric coefficients were obtained by fitting the experimental data. Because all four C-H bonds in a methane molecule are equivalent, multiple substitutions during methane conversion cannot be avoided. Our studies indicate that mono-substituted and di-substituted methane isotopologue generations have similar activation energies, suggesting that the highest mono-substitution selectivity cannot be greater than 50%.

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CoFe/SBA-15 catalyst coupled with peroxymonosulfate for heterogeneous catalytic degradation of rhodamine B in water Longxing Hu, Fan Yang, Lianpei Zou, Hang Yuan, Xing Hu 2015, 36 (10):  1785-1797.  DOI: 10.1016/S1872-2067(15)60939-1 Abstract ( 317 )   [Full Text(HTML)] () PDF (972KB) ( 848 )   CoFe/SBA-15 catalysts were prepared by simultaneous incipient wetness impregnation using Co(NO3)2·6H2O and Fe(NO3)3·9H2O as the precursors and SBA-15 as the support. The catalysts were used to activate generation of sulfate radicals from peroxymonosulfate (PMS) for rhodamine B (RhB) dye degradation in aqueous solutions. The catalyst was characterized using X-ray diffraction, N2 adsorption-desorption, scanning electron microscopy and energy-dispersive X-ray spectroscopy, transmission electron microscopy, and vibrating sample magnetometry. The effects of the Co and Fe loadings and calcination temperature on the catalytic performance, catalyst reusability, and kinetics and mechanism of catalytic oxidative degradation of RhB in the presence of CoFe/SBA-15 and PMS were investigated. The results show that the predominant Co-Fe oxide loaded on the support was the composite CoFe2O4, which provided the active catalytic sites, and was present in the SBA-15 matrix. The surface area, pore volume, and mean pore diameter of 10Co9.5Fe/SBA-15-700 were 506.1 m2/g, 0.669 cm3/g, and 7.4 nm, respectively, lower than those of SBA-15. 10Co9.5Fe/SBA-15-700 consisted of rod-like aggregates with diameters greater than 0.25 μm. It had a magnetic intensity of 8.3 emu/g; therefore, magnetic separation was feasible. 10Co9.5Fe/SBA-15-700 showed good catalytic activity and stability, with a RhB degradation rate higher than 96% and Co leaching lower than 32.4 μg/L. The catalytic oxidative degradation of RhB in the presence of FeCo/SBA-15 and PMS obeyed first-order kinetics, and the degradation rate increased with increasing CoFe/SBA-15 and PMS dosages and with decreasing initial reactant concentrations. Quenching tests showed that sulfate radicals played a dominant role in RhB catalysis. CoFe/SBA-15 maintained high catalytic activity and good stability during 10 recycling runs, with a RhB degradation rate greater than 84%, Co and Fe leaching for each run lower than 72.1 and 35 μg/L, respectively. CoFe/SBA-15 is an efficient catalyst for PMS oxidation, and has potential applications in the removal of refractory organics such as RhB in water.