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Chinese Journal of Catalysis
2014, Vol. 35, No. 9
Online: 19 August 2014


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Prof. He and his coworkers in their Article on pages 1438-1445 reported the laboratory study of catalyst formulation and washcoating technology for the V₂O₅-WO₃/TiO₂ system, and also the establishment of an NH₃-SCR (selective catalytic reduction of NO_x with NH₃) catalyst production line of which the product can make the heavy duty diesel vehicles meet the China IV emission standard.

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Table of Contents for VOL.35 No.9 2014, 35 (9):  0-0.  Abstract ( 156 )   PDF (1993KB) ( 598 )

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Recent progress on photocatalysts with wide visible light range absorption for heterogeneous water splitting Shanshan Chen, Fuxiang Zhang 2014, 35 (9):  1431-1432.  DOI: 10.1016/S1872-2067(14)60183-2 Abstract ( 245 )   [Full Text(HTML)] () PDF (422KB) ( 671 )

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Oxidation of dibenzothiophene using oxygen and a vanadophosphate catalyst for ultra-deep desulfurization of diesels Nanfang Tang, Xiaoping Zhao, Zongxuan Jiang, Can Li 2014, 35 (9):  1433-1437.  DOI: 10.1016/S1872-2067(14)60194-7 Abstract ( 298 )   [Full Text(HTML)] () PDF (623KB) ( 612 )   A bicapped Keggin structure vanadophosphate showed high catalytic activity in the oxidation of dibenzothiophene (DBT) to sulfone using molecular oxygen as oxidant under mild reaction conditions. This is a promising approach to the ultra-deep desulfurization of fuels (e.g. diesel) as sulfones can be removed from the fuel by extraction or selective adsorption.

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Selective catalytic reduction of NOx by NH3 for heavy-duty diesel vehicles Fudong Liu, Wenpo Shan, Dawei Pan, Tengying Li, Hong He 2014, 35 (9):  1438-1445.  DOI: 10.1016/S1872-2067(14)60048-6 Abstract ( 364 )   [Full Text(HTML)] () PDF (724KB) ( 712 )   A catalyst production line with a production capacity of 6000 catalyst monoliths per month for the selective catalytic reduction of NOx by NH3 (NH3-SCR) for NOx abatement in diesel vehicle exhaust was set up based on a detailed laboratory study of the catalyst formulation and washcoating technology for V2O5-WO3/TiO2 catalyst. The catalyst produced by this line was tested on a bench scale diesel engine. The V2O5-WO3/TiO2 powder catalyst prepared in the laboratory and production line both achieved >80% NOx conversion at 200-450 ℃ and a GHSV of 50000 h-1. The washcoated catalyst used a large cordierite support and gave >80% NOx conversion at 250-450 ℃ and GHSVs of 10000-30000 h-1. The engine bench tests showed that after treatment by the catalyst, the NOx emission met the European steady-state cycle (ESC) and European transient cycle (ETC) limits of the China IV standard. The production line can also be used for the production of vanadium-free NH3-SCR catalysts to meet the required replacement of the present vanadium-based NH3-SCR catalyst in the future.

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Chiral MnⅢ(Salen) supported on tunable phenoxyl group modified zirconium poly (styrene-phenylvinylphosphonate)-phosphate as an efficient catalyst for epoxidation of unfunctionalized olefins Xiaochuan Zou, Kaiyun Shi, Cun Wang 2014, 35 (9):  1446-1455.  DOI: 10.1016/S1872-2067(14)60064-4 Abstract ( 353 )   [Full Text(HTML)] () PDF (719KB) ( 598 )   We have developed a series of chiral MnⅢ(Salen) (chiral Jacobsen's catalyst) catalysts that were axially supported onto zirconium poly(styrene-phenylvinylphosphonate)-phosphate through tunable phenoxyl linkers of varying steric hindrance, and evaluated their performance as catalysts (Cat1-Cat3) for the epoxidation of unfunctionalized olefins using m-chloroperbenzoic acid as an oxidant. The corresponding non-supported analogues (Cat4-Cat6) were also prepared and tested under similar conditions. The results demonstrated that the incorporation of substituents at the ortho-positions of the tunable phenoxyl linkers had a critical effect on the catalytic activity. Furthermore, the enantioselectivity increased as the steric hindrance imposed by the linker increased, although this also led to a decrease in the conversions under the same reaction conditions, especially for heterogeneous epoxidation. The heterogeneous system also displayed high ee values and conversions in the absence of the axial additive N-methylmorpholine N-oxide, which is commonly required to improve the catalytic activity of epoxidation reactions, especially for the epoxidation of α-methylstyrene. The reusability of the catalyst was also evaluated over 11 catalytic cycles, with no significant reduction observed in the catalytic activity or enantioselectivity after five runs.

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Rh catalysts supported on knitting aryl network polymers for the hydroformylation of higher olefins Miao Jiang, Yunjie Ding, Li Yan, Xiangen Song, Ronghe Lin 2014, 35 (9):  1456-1464.  DOI: 10.1016/S1872-2067(14)60068-1 Abstract ( 274 )   [Full Text(HTML)] () PDF (908KB) ( 723 )   Rh catalysts supported on knitting aryl network polymers (Rh/KAPs) were prepared for the hydroformylation of higher olefins. Rh catalysts supported on triphenylphosphine-benzene-base polymers (Rh/KAPs-1) showed higher activity for the higher olefins than Rh/SiO2 catalysts. Fourier transform infrared spectroscopy, thermogravimetry, N2 adsorption-desorption, X-ray diffraction, transmission electron microscopy, 13C NMR, and 31P NMR showed that the Rh/KAPs-1 catalysts have high thermal stability, high surface area, hierarchical porosity, highly dispersed Rh nanoparticles, and in situ formed homogeneous active species during the reaction.

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Ozone catalytic oxidation of benzene over AgMn/HZSM-5 catalysts at room temperature：Effects of Mn loading and water content Yang Liu, Xiaosong Li, Jinglin Liu, Chuan Shi, Aimin Zhu 2014, 35 (9):  1465-1474.  DOI: 10.1016/S1872-2067(14)60070-X Abstract ( 342 )   [Full Text(HTML)] () PDF (731KB) ( 593 )   The effects of Mn loading and water content on AgMn/HZSM-5 (AgMn/HZ) catalysts were investigated in the ozone catalytic oxidation (OZCO) of benzene in a continuous air flow at room temperature. The catalytic activity is closely related to the Mn loading, and the AgMn/HZ catalyst with 2.4 wt% Mn (AgMn/HZ(2.4)) had the highest activity and stability in benzene oxidation as a result of its large surface area and high MnOx dispersion. Temperature-programmed desorption of the used catalysts demonstrated that 2.4 wt% was also the optimal Mn loading for suppressing the accumulation of benzene and HCOOH over the catalyst surface after benzene oxidation. For AgMn/HZ catalysts with Mn loadings ≤ 2.4 wt%, O3 decomposition to active oxygen species (O*) plays the most important role in benzene oxidation; however, benzene activation is the crucial step for benzene oxidation by O3 over AgMn/HZ catalysts with Mn loadings > 2.4 wt%. The AgMn/HZ(2.4) catalyst was then used to perform OZCO of benzene in a humid stream. Compared with dry gas, water vapor greatly enhanced the activity and stability of the AgMn/HZ(2.4) catalyst, and 0.1-0.2 vol% was the optimal water content for benzene oxidation.

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Nanoplate-aggregate Co3O4 microspheres for toluene combustion Fang Wang, Hongxing Dai, Jiguang Deng, Shaohua Xie, Huanggen Yang, Wen Han 2014, 35 (9):  1475-1481.  DOI: 10.1016/S1872-2067(14)60072-3 Abstract ( 280 )   [Full Text(HTML)] () PDF (1205KB) ( 556 )   Nanoplate-aggregate microspherical Co3O4 was prepared by an ethylenediamine-assisted hydrothermal route and characterized by means of numerous techniques. Their catalytic activities for toluene combustion were evaluated. The Co3O4 sample obtained using 1.0 ml of ethylenediamine and a hydrothermal treatment at 140 ℃ for 12 h had a nanoplate-aggregate microspherical morphology. This microspherical Co3O4 sample with a surface area of 66 m2 g-1 had a higher adsorbed oxygen concentration and better low-temperature reducibility than bulk Co3O4. Over the Co3O4 microsphere sample, the temperatures required for 50% and 90% toluene conversions were 230 and 254 ℃, respectively, at a space velocity of 20000 ml g-1 h-1. The good catalytic performance of the Co3O4 microsphere sample was related to its large surface area, high oxygen adspecies concentration, and good low-temperature reducibility.

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A new monolithic Pt-Pd-Rh motorcycle exhaust catalyst to meet future emission standards Suning Wang, Yajuan Cui, Li Lan, Zhonghua Shi, Ming Zhao, Maochu Gong, Ruimei Fang, Sijie Chen, Yaoqiang Chen 2014, 35 (9):  1482-1491.  DOI: 10.1016/S1872-2067(14)60092-9 Abstract ( 284 )   [Full Text(HTML)] () PDF (692KB) ( 815 )   A new composite oxide material as support, CeO2-ZrO2-La2O3-PrO2-Al2O3, was synthesized by a co-precipitation method. Pd-Rh, Pt-Rh, and Pt-Pd-Rh supported on monolithic carrier catalysts were obtained by an impregnation route. The textural, structural, and reductive properties of the catalysts were characterized by N2 adsorption-desorption, temperature-programmed reduction, oxygen storage capacity measurements, and X-ray diffraction. The air-fuel-ratio (A/F), space velocity (SV), and temperature characteristics of the fresh and aged catalysts were investigated on a systematic basis. The results showed that among the three catalysts, Pt-Pd-Rh displayed the best performance. For an SV of 40000 h-1 in the case of fresh Pt-Pd-Rh, the light-off temperatures (T50) for C3H8, CO, and NO were 239, 187, and 191 ℃, respectively, with corresponding ΔT (T90-T50) values of 21, 3, and 3 ℃, respectively. After aging, the T50 for C3H8, CO, and NO were 298, 203, and 223 ℃, respectively, and the ΔT values were 22, 5, and 13 ℃, respectively. Moreover, the window widths for the A/F in the case of fresh and aged Pt-Pd-Rh catalysts were wide. Overall, the excellent performance for the Pt-Pd-Rh catalyst makes it suitable as a motorcycle exhaust catalyst, which can meet future emission standards.

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Synthesis of novel hierarchical ZSM-5 monoliths and their application in trichloroethylene removal João Pires, Ana C. Fernandes, Divakar Duraiswami 2014, 35 (9):  1492-1496.  DOI: 10.1016/S1872-2067(14)60085-1 Abstract ( 232 )   [Full Text(HTML)] () PDF (614KB) ( 782 )   A self-supporting ZSM-5 monolith with a hierarchical porosity was prepared using polyurethane foam (PUF) as a structural template and a hydrothermal synthesis procedure. The synthesized monolith was characterized and investigated towards the adsorption and catalytic oxidation of trichloroethylene (TCE). Adsorption of TCE was studied gravimetrically and oxidation of TCE was studied using a vapor-phase down-flow reactor. Monolithic ZSM-5 displayed good sorption properties and completely oxidized TCE. Conversion levels of 50% and 90% were achieved at reduced temperatures (by ~50 ℃) when compared with the conversion temperatures obtained from the powder counterparts. Besides the activity of the monolith towards TCE adsorption and oxidation, it was stable and enhanced diffusion, thereby reducing pressure drops to a great extent owing to its hierarchical porous nature.

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One-pot multicomponent synthesis of unsymmetrical polyhydroquinoline derivatives with 1,1’-butylenebispyridinium hydrogen sulfate as an efficient, halogen-free and reusable Brönsted ionic liquid catalyst Nader Ghaffari Khaligh 2014, 35 (9):  1497-1503.  DOI: 10.1016/S1872-2067(14)60087-5 Abstract ( 261 )   [Full Text(HTML)] () PDF (675KB) ( 598 )   1,1'-Butylenebispyridinium hydrogen sulfate is an efficient, halogen-free and reusable Brönsted ionic liquid catalyst for the synthesis of ethyl-4-aryl/heteryl-hexahydro-trimehtyl-5- oxoquinoline-3-carboxylates by the one-pot condensation of dimedone, aryl/heteryl aldehydes, ethyl acetoacetate, and ammonium acetate under solvent-free conditions. This method has the advantages of high yield, clean reaction, simple methodology, and short reaction time. The ionic liquid can be recycled five times without significant loss of the catalytic activity.

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Effect of sulfur poisoning on Co3O4/CeO2 composite oxide catalyst for soot combustion Xiaoyan Shi, Yunbo Yu, Li Xue, Hong He 2014, 35 (9):  1504-1510.  DOI: 10.1016/S1872-2067(14)60088-7 Abstract ( 261 )   [Full Text(HTML)] () PDF (677KB) ( 695 )   CeO2, Co3O4, and a series of Co3O4/CeO2 composite oxides prepared by co-precipitation were exposed to SO2 under an oxidizing environment at 400 ℃. These fresh and SO2-poisoned samples were characterized by in situ diffuse reflectance infrared Fourier transform spectroscopy, X-ray diffraction, temperature-programmed desorption, and X-ray photoelectron spectroscopy. Sulfates were formed on the oxides, with more sulfates on CeO2 than on Co3O4. On the Co3O4/CeO2 composite oxides, both cobalt sulphate and ceria sulfate were formed. Fresh and sulfated samples were tested for soot combustion in a NO/O2 gas flow. The Co3O4/CeO2 composite oxides showed better SO2 tolerance and higher activity than CeO2 but were more easily poisoned by SO2 than Co3O4.

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Ti3+ and carbon co-doped TiO2 with improved visible light photocatalytic activity Yunchang Liu, Mingyang Xing, Jinlong Zhang 2014, 35 (9):  1511-1519.  DOI: 10.1016/S1872-2067(14)60093-0 Abstract ( 325 )   [Full Text(HTML)] () PDF (952KB) ( 944 )   Using ethanol as the carbon source, a series of Ti3+ and carbon co-doped TiO2 samples were successfully synthesized by an innovative and simple vacuum activation method in a one-step process. The Ti3+ self-doped TiO2 featured a high visible light photocatalytic activity that improved considerably following subsequent carbon doping modification of the catalyst surface. The samples were characterized by X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, electron spin resonance, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The Ti3+ and C co-doped TiO2 catalyst showed a high methyl orange photo-degradation efficiency under visible light irradiation. The doping levels induced by Ti3+ and oxygen vacancies were responsible for the improved visible light response of TiO2. Simultaneously, the surface coverage of graphite on the catalyst could improve the absorption of visible light and migration efficiency of photo-induced electrons. The synergistic effects of Ti3+ self-doping and graphite coverage led to the improved visible light photocatalytic activity of Ti3+ and C co-doped TiO2.

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Effects of Nd, Ce, and La modification on catalytic performance of Ni/SBA-15 catalyst in CO2 reforming of CH4 Huimin Liu, Yuming Li, Hao Wu, Weiwei Yang, Dehua He 2014, 35 (9):  1520-1528.  DOI: 10.1016/S1872-2067(14)60095-4 Abstract ( 312 )   [Full Text(HTML)] () PDF (732KB) ( 731 )   Rare-earth metal (Nd, Ce, and La) oxides modified Ni/SBA-15 catalysts were prepared by a β-cyclodextrin-modified impregnation method. The physicochemical properties of the catalysts were characterized using X-ray diffraction, N2 adsorption-desorption, temperature-programmed reduction, and thermogravimetric analysis. The catalytic performance of the catalysts was evaluated in the CO2 reforming of CH4 to syngas. The characterization results showed that Nd, Ce, and La modification had little effect on the textural structures and crystalline phases of the obtained catalysts but influenced the reduction of NiO species. Addition of Nd favored interactions between Ni and SiO2, possibly as a result of the formation of Ni-Nd-O species. The results for the CO2 reforming of CH4 revealed that the addition of suitable amounts of Nd (5-10 wt%) improved the catalytic activity and stability. A small amount of carbon was deposited over the used Nd-modified catalysts. The properties of Ni/SBA-15 catalysts modified with La and Ce were similar to those of the Nd-modified catalysts.

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Selective oxidation of alcohols over copper zirconium phosphate Abdol R. Hajipour, Hirbod Karimi 2014, 35 (9):  1529-1533.  DOI: 10.1016/S1872-2067(14)60096-6 Abstract ( 343 )   [Full Text(HTML)] () PDF (727KB) ( 728 )   The catalytic activity of copper zirconium phosphate (ZPCu) in the selective oxidation of alcohols to their corresponding ketones or aldehydes, using H2O2 as an oxidizing agent, was studied. The oxidation reaction was performed without any organic solvent, phase-transfer catalyst, or additive. Steric factors associated with the substrates influenced the reaction. The catalyst was characterized using X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. It was shown that the interlayer distance increased from 0.74 to 0.80 nm and the crystallinity was reduced after Cu2+ intercalation into the layers. This catalyst can be recovered and reused three times without significant loss of activity and selectivity.

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Biotransformation of geniposide in Gardenia jasminoides to genipin by Trichoderma harzianum CGMCC 2979 Yuesheng Dong, Leping Liu, Yongming Bao, Aiyu Hao, Ying Qin, Zujia Wen, Zhilong Xiu 2014, 35 (9):  1534-1546.  DOI: 10.1016/S1872-2067(14)60134-0 Abstract ( 254 )   [Full Text(HTML)] () PDF (924KB) ( 772 )   Trichoderma harzianum (T. harzianum) CGMCC 2979 was used to transform the geniposide in Gardenia jasminoides (G. jasminoides) to genipin, dispensing the use of purified enzyme and the extraction of geniposide from the raw material. At 30 ℃, pH 6.1, and an initial G. jasminoides concentration of 80 g dried fruit per liter of medium, the geniposide-to-genipin conversion rate reached 97.8% after 48 h of fermentation. The genipin was purified from the fermentation broth by a combined method of XAD-16N-resin and silica-gel chromatography, yielding a total recovery of 62.3%. A 74.4-kDa geniposide-β-glucosidase implicated in the transformation of geniposide to genipin was purified from T. harzianum CGMCC 2979. It had optimum activity at 50 ℃ and pH 4.0-5.0. The Km and Vmax of the enzyme for geniposide were 3.6 mmol/L and 775 μmol/h/mg protein, respectively. The simple, direct, and efficient biotransformation of geniposide in G. jasminoide to genipin by T. harzianum CGMCC 2979 that is described in this study could represent an alternative and effective method for producing genipin.

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Immobilized Pd nanoparticles on Tris-modified SiO2：Synthesis, characterization, and catalytic activity in Heck cross-coupling reactions Abdol R. Hajipour, Ghobad Azizi 2014, 35 (9):  1547-1554.  DOI: 10.1016/S1872-2067(14)60109-1 Abstract ( 196 )   [Full Text(HTML)] () PDF (948KB) ( 620 )   The preparation of supported Pd nanoparticles on Tris (tris(hydroxymethyl)aminomethane)- modified SiO2 gel and their catalytic application in Heck coupling are investigated. The catalyst was characterized using a combination of X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy, and scanning electron microscopy/energy-dispersive X-ray spectroscopy. The supported Pd nanoparticles were found to be a highly active and reusable catalyst for the Heck reaction at a low Pd loading (0.02 mol%) because of stabilization by the Tris moieties. Several reaction parameters, including the type and amount of solvent, base, and temperature, were evaluated. The heterogeneity of the catalytic system was investigated using different approaches, and showed that slight Pd leaching into the reaction solution occurred under the reaction conditions. Despite this metal leaching, the catalyst can be reused seven times without significant loss of its activity.

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Covalent immobilization of Candida antarctica lipase B on nanopolystyrene and its application to microwave-assisted esterification Attaullah Bukhari, Ani Idris, Madiha Atta, Teo Chee Loong 2014, 35 (9):  1555-1564.  DOI: 10.1016/S1872-2067(14)60111-X Abstract ( 305 )   [Full Text(HTML)] () PDF (602KB) ( 646 )   Nanopolystyrene was used as a solid support for the covalent immobilization of Candida antarctica lipase B (CalB) using the photoreactive reagent 1-fluoro-2-nitro-4-azido benzene (FNAB) as a coupling reagent. The obtained derivative was then used as a biocatalyst in a microwave assisted esterification experiment. Factors such as contact time, pH, and enzyme concentration were investigated during immobilization. The hydrolytic activity, thermal, and operational stability of immobilized-CalB were determined. The maximum immobilized yield (218 μg/mg support) obtained at pH 6.8 exhibited optimum hydrolytic activity (4.42 × 103 mU p-nitrophenol/min). The thermal stability of CalB improved significantly when it was immobilized at pH 10, however, the immobilized yield was very low (93.6 μg/mg support). The immobilized-CalB prepared at pH 6.8 and pH 10 retained 50% of its initial activity after incubation periods of 14 and 16 h, respectively, at 60 ℃. The operational stability was investigated for the microwave assisted esterification of oleic acid with methanol. Immobilized-CalB retained 50% of its initial activity after 15 batch cycles in the microwave-assisted esterification. The esterification time was notably reduced under microwave irradiation. The combined use of a biocatalyst and microwave heating is thus an alternative total green synthesis process.

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Silver nanoparticle decorated poly(2-aminodiphenylamine) modified carbon paste electrode as a simple and efficient electrocatalyst for oxidation of formaldehyde Reza Ojani, Saeid Safshekan, Jahan-Bakhsh Raoof 2014, 35 (9):  1565-1570.  DOI: 10.1016/S1872-2067(14)60115-7 Abstract ( 292 )   [Full Text(HTML)] () PDF (557KB) ( 566 )   This work describes the promising activity of silver nanoparticles on the surface of a poly(2-amino diphenylamine) modified carbon paste electrode (CPE) towards formaldehyde oxidation. Electrodeposition of the conducting polymer film on the CPE was carried out using consecutive cyclic voltammetry in an aqueous solution of 2-aminodiphenylamine and HCl. Nitrogen groups in the polymer backbone had a Ag ion accumulating effect, allowing Ag nanoparticles to be electrochemically deposited on the surface of the electrode. The electrochemical and morphological characteristics of the modified electrode were investigated. The electro-oxidation of formaldehyde on the surface of electrode was studied using cyclic voltammetry and chronoamperometry in aqueous solution of 0.1 mol/L NaOH. The electro-oxidation onset potential was found to be around -0.4 V, which is unique in the literature. The effect of different concentrations of formaldehyde on the electrocatalytic activity of the modified electrode was investigated. Finally, the diffusion coefficient of formaldehyde in alkaline media was calculated to be 0.47 × 10-6 cm2/s using chronoamperometry.

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Kinetics and efficiency displayed by supported and suspended TiO2 catalysts applied to the disinfection of Escherichia coli Majdi Kacem, Gael Plantard, Nathalie Wery, Vincent Goetz 2014, 35 (9):  1571-1577.  DOI: 10.1016/S1872-2067(14)60125-X Abstract ( 203 )   [Full Text(HTML)] () PDF (628KB) ( 436 )   TiO2-mediated photocatalysis is widely used in a variety of applications and products in the environmental and energy fields, including photoelectrochemical conversion, self-cleaning surfaces, and especially water purification systems. The dimensionality of the structure of a TiO2 material can affect its properties, functions, and more specifically, its photocatalytic performance. In this work, the photocatalytic inactivation of Gram-negative Escherichia coli using three photocatalysts, differing in their structure and other characteristics, was studied in a batch reactor under UVA light. The aim was to establish the disinfection efficiency of solid TiO2 compared with that of suspended catalysts, widely considered as reference cases for photocatalytic water disinfection. The bacterial inactivation profiles obtained showed that: (1) the photoinactivation was exclusively related to the quantity of photons retained per unit of treated volume, irrespective of the characteristics of the photocatalyst and the emitted light flux densities; (2) across the whole UV light range studied, each of the photocatalytic solids was able to achieve more than 2 log bacterial inactivation with less than 2 h UV irradiation; (3) none of the used catalysts achieved a total bacterial disinfection during the treatment time. For each of the catalysts the quantum yield has been assessed in terms of disinfection efficiency, the 2D material showed almost the same performance as those of suspended catalysts. This catalyst is promising for supported photocatalysis applications.

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Preparation of Bi-doped TiO2 nanoparticles and their visible light photocatalytic performance Haiyan Li, Jinfeng Liu, Junjie Qian, Qiuye Li, Jianjun Yang 2014, 35 (9):  1578-1589.  DOI: 10.1016/S1872-2067(14)60124-8 Abstract ( 468 )   [Full Text(HTML)] () PDF (1154KB) ( 783 )   Bi-doped TiO2 photocatalysts were prepared by a hydrothermal method using nanotube titanic acid as the Ti precursor. The samples were characterized by X-ray diffraction, transmission electron microscopy, ultraviolet-visible diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. Methyl orange (MO) was used as a model contaminant to evaluate the visible light photocatalytic activity of the Bi-doped TiO2 samples. We found that the Bi ions did not incorporate into the TiO2 lattice but instead existed in the form of BiOCl. The obtained BiOCl-composited TiO2 samples exhibited remarkable photocatalytic activity under visible light irradiation for the photodegradation of MO. The sample obtained when the Bi/Ti molar ratio was 1% and the hydrothermal treatment temperature was 130 ℃ (BTO-130-1) showed the highest photocatalytic activity. Moreover, a possible mechanism was proposed and the enhanced photocatalytic activity was discussed. The as-prepared catalyst also showed high photocatalytic activity for the photodegradation of 4- chlorophenol.