Titanium Silicate Research Articles

Oxidation of Furfural and Furan Derivatives to Maleic Acid in the Presence of a Simple Catalyst System Based on Acetic Acid and TS-1 and Hydrogen Peroxide.

Titanium silicate molecular sieve (TS-1) and acetic acid efficiently catalyze the oxidation of furan and furan derivatives to the corresponding maleic acid (MA) in very good yields using hydrogen peroxide as an oxidizing agent. The effect of various solvents, the effect of temperature, reaction time, concentration of hydrogen peroxide, and quantities of the catalyst on the MA yield was studied. With the best conditions, MA is the sole product obtained after a fast and simple purification by filtration and evaporation. Compared to the previously reported methods, this work is a good compromise between the different reaction parameters and offers a good alternative to the production of biosourced MA.

From structure topology to chemical composition. XXVII. Revision of the crystal chemistry of the perraultite-type minerals of the seidozerite supergroup: Jinshajiangite, surkhobite, and bobshannonite

ABSTRACTThe crystal structures of the three perraultite-type minerals (bafertisite group, seidozerite supergroup)—jinshajiangite from Norra Kärr, Sweden, ideally NaBaFe2+4Ti2(Si2O7)2O2(OH)2F, Z = 4; surkhobite (holotype) from the Darai-Pioz massif, Tajikistan, ideally NaBaMn4Ti2(Si2O7)2O2(OH)2F, Z = 4; and bobshannonite (holotype) from Mont Saint-Hilaire, Canada, ideally Na2KBa(Mn7Na)Nb4(Si2O7)4O4(OH)4O2, Z = 2—were refined in space group C to R1 = 2.73, 2.85, and 2.02% on the basis of 2746, 2657, and 4963 unique reflections [Fo > 4σFo], respectively. Refinement was done using data from twinned crystals (jinshajiangite: three twin components; surkhobite and bobshannonite: two twin components). The parameters of a C-centered triclinic unit cell are as follows: jinshajiangite: a = 10.720(5), b = 13.823(7), c = 11.044(6) Å, α = 108.222(6), β = 99.28(1), γ = 89.989(6)°, V = 1532.0(2.2) Å3; surkhobite: a = 10.728(6), b = 13.845(8), c = 11.072(6) Å, α = 108.185(6), β = 99.219(5), γ = 90.001(8)°, V = 1540.0(2.5) Å3; and bobshannonite: a = 10.831(7), b = 13.903(9), c = 11.149(8) Å, α = 108.145(6), β = 99.215(9), γ = 90.007(7)°, V = 1572.6(3.2) Å3. New electron microprobe data are reported for the holotype surkhobite and new IR data for jinshajiangite. In the perraultite-type structure (structure type B1BG, B – basic, BG – bafertisite group), there is one type of TS (Titanium-Silicate) block and one type of I (Intermediate) block; they alternate along c. The TS block consists of HOH sheets (H-heteropolyhedral, O-octahedral). In the O sheet, the ideal composition of the five [6]MO sites is Fe2+4apfu (jinshajiangite), Mn4apfu (surkhobite), and (Mn7Na) (bobshannonite). There is no order of Fe2+ and Mn in the O sheet. In the H sheet, the ideal composition of the two [6]MH sites is Ti2apfu (jinshajiangite, surkhobite) and Nb4apfu (bobshannonite). The four [4]Si sites are occupied solely by Si. The MH octahedra and Si2O7 groups constitute the H sheet. The TS blocks link via common vertices of MH octahedra. The I block contains AP(1,2) and BP(1,2) cation sites. In the I block of jinshajiangite and surkhobite, the AP(1) site is occupied by Ba and the AP(2) site by K > Ba; the ideal composition of the two AP(1,2) sites is Ba apfu. In the I block of bobshannonite, Ba and K are ordered at the AP(1) and AP(2) sites, Ba:K ∼ 1:1 , ideally BaK apfu. The two BP(1,2) sites are each occupied by Na > Ca, ideally Na apfu (jinshajiangite, surkhobite) and solely by Na, ideally Na2apfu (bobshannonite). There is no order of Na and Ca at the BP(1,2) sites in jinshajiangite and surkhobite [currently defined as a Ca-ordered analogue of perraultite, ideally NaBaMn4Ti2(Si2O7)2O2(OH)2F, Z = 4]. The ideal formulae of surkhobite, KBa3Ca2Na2Mn16Ti8(Si2O7)8O8(OH)4(F,O,OH)8 (current IMA formula) and of bobshannonite, Na2KBa(Mn,Na)8(Nb,Ti)4(Si2O7)4O4(OH)4(O,F)2 (current IMA formula) have been revised as follows: NaBaMn4Ti2(Si2O7)2O2(OH)2F, Z = 4 (surkhobite) and Na2KBa(Mn7Na)Nb4(Si2O7)4O4(OH)4O2, Z = 2 (bobshannonite). The revised ideal formula of surkhobite is identical to the ideal formula of perraultite and hence surkhobite should be discredited.

Composition Material for Radiation Protection Based on Modified Disperse Titanium Hydride and Silicate Connecting

This paper presents an analysis of known radiation protection materials. The prospects of using materials based on titanium hydride are shown. The possibility of obtaining finely ground titanium hydride with a high content of atomic hydrogen in its structure has been established. The features of the physicochemical interaction of dispersed titanium hydride and heavy flint, after hydrolysis in the alkaline environment of the organosilicon modifier – tetraethoxysilane, are revealed. The possibility of obtaining a thermostable low-activated composite material based on dispersed titanium hydride for complex protection against neutron and gamma radiation has been established. The structure of the obtained composite was investigated.

Mineralogical Characterization of Heavy Mineral Concentrates from Senegalese Great Cost by Using Qemscan and SEM

The heavy mineral sands of Senegal are exploited to extract titanium oxides and zircon. Mining is carried out first by means of a floating dredge and concentration plant which produces a heavy mineral concentrate (HMC) containing on average 78% titanium oxides, 11% zircon and a set of silicate and alumino-silicate minerals. This heavy mineral concentrate is then treated by gravity, magnetic and electrostatic separation to produce titanium oxide concentrates (ilmenite, leucoxene, rutile) and three varieties of zircon concentrates (Premium zircon, standard zircon and medium grade zircon standard). In this study, we describe the various mineral concentrates in terms of mineralogical assemblages, and textural variability within grains, using Qemscan and Scanning Electron Microscopy. The titanium oxide concentrates are differentiated by their TiO2 content and vary from ilmenite to rutile. The zircon concentrates are characterized by the presence of impurities in the zircons, which consist in numerous inclusions of titanium oxides and silicate minerals. The mineralogical characteristics determined by scanning electron microscopy and by Qemscan showed great variability within the grains themselves. Heavy minerals contain many mineral inclusions and show strong chemical zoning.

Feasibility of Biological Elimination of COD, Ammonia-Nitrogen and Total Nitrogen from HTS Molecular Sieves Wastewater Using SBR Processes

The wastewater from hollow titanium silicate (HTS) zeolite consists essentially of high concentrations of COD and salt, and low ammonia-nitrogen concentrations (or high, sometimes). These chemical pollutants are produced in very large quantities during oil refining and are very difficult to manage on site. In addition, they can be very harmful to the environment when released without any treatment. The aim of this study is to evaluate, on the one hand, the feasibility of removing the COD from HTS wastewater using a sequencing batch reactor (SBR) and, on the other hand, to test the combined effect of nitrification and denitrification under different conditions of treatment on the elimination of Total Nitrogen (TN) from HTS wastewater containing a high concentration of ammonia-nitrogen. SBR intermittent domestication tests of sludge have been successfully carried out with wastewater from a municipal treatment plant with a COD removal rate of 87%. Subsequently, HTS wastewater containing high concentrations of COD was treated by this SBR system. After three months of operation, the efficiency of COD elimination fluctuated between 47% and 67%. Therefore this result could serve as a precursor to a possible second COD bioprocessing. The results obtained during nitrification of the same HTS molecular sieves wastewater with low C/N ratio gave, under an operating temperature below 10°C (winter conditions), less than 16% of total nitrogen (TN) removal. When the temperature was increased to 40°C, the TN removal efficiency remained worse. These observations make it possible to affirm that the change in temperature solely had no effect on oxidation of TN. Thereafter, two SBR devices were used for the denitrification process: one containing HTS wastewater, activated sludge and glucose as carbon source, and the other only HTS wastewater and activated sludge. In both cases, the elimination of TN still low even with an increase in the amount of glucose. These situations show that the TN removal was not only depended on type of carbon source. Based on the results of nitrification and denitrification tests, it may turn out that the activated sludge microorganisms’ activities were affected by the HTS molecular sieves wastewater high concentration as well as the salinity (about 3%) of this kind of wastewater.

The nitriding of titanium silicate-1 and its effect on gas-phase epoxidation of propylene

The nitrogen-containing titanium silicate-1 (N-TS-1) was synthesized to improve the catalytic performance of Au/N-TS-1 in gas-phase epoxidation of propylene. The nitrogen content has an important influence on the activity of the catalyst and can be controlled by adjusting the nitriding temperature and the nitriding time. The propylene oxide (PO) formation rate was promoted from 78.7 gPO/h/kgCat of Au/TS-1 to 138.7 gPO/h/kgCat of Au/N-TS-1 (nitrided at the optimal condition). It was found that the ligand effect of terminal-NH2 caused by nitrogen enrichment increased the Au capture efficiency and the gold loading. And the reduction in the acid amount on the surface of the molecular sieve caused by nitridation reduced the adsorption of PO on the surface of the support.

Facile Preparation of Bilayer Titanium Silicate (TS-1) Zeolite Membranes by Periodical Secondary Growth

A facile periodical secondary growth method, based on conventional secondary growth, is proposed to prepare bilayer TS-1 membranes. The novel periodical secondary growth consists of two or several periods, which involve three steps: the temperature is programmed to a desired crystallization temperature as the first stage, followed by holding for a certain duration, and finally cooling to room temperature. This periodical crystallization model enables a bilayer TS-1 membrane to be produced, while the conventional secondary growth method produces a monolayer TS-1 membrane. The bilayer TS-1 membrane exhibits a superior defect-free structure and hydrophobic properties, as illustrated by SEM, gas permeance, pore size distribution analysis, and water contact angle measurement. It displays an earlier desalination separation factor compared to the monolayer TS-1 membrane. This work demonstrates that the periodical secondary growth is an advanced approach for preparing a bilayer zeolite membrane with excellent properties.

Novel Biomass‐Derived Adsorbents Grafted Sodium Titanium Silicate with High Adsorption Capacity for Rb+ and Cs+ in the Brine

AbstractTwo biomass‐derived adsorbents (BCA@STS, CBCA@STS) modified with sodium titanium silicate (STS) were synthesized through a hydrothermal deposition method and tested to adsorb Rb+ and Cs+ from aqueous solution and brine. The BET characterization results showed that the adsorbents had mesoporous structures and excellent adsorption capacity for Rb+ and Cs+ with the maximum adsorption amounts as high as 2.07 mmol g−1 and 1.47 mmol g−1, respectively. XRD and XPS analyses of the adsorbents before and after adsorption revealed that the high adsorption capacity is attributed to the Na+ located in the adsorbents and ion exchange between Na+ and Rb+ or Cs+ is the key mechanism. The chemical composition of functional substance is the mixture of (HNa)O⋅SiO2⋅2TiO2⋅2H2O and Na2Ti3O7. The adsorption amounts increase with increasing of pH, and decrease with the increase of NaCl concentration due to the competitive adsorption between H+/Na+ and Rb+/Cs+. The adsorption kinetics of both these two adsorbents were well fitted to the pseudo‐second order kinetic model indicating that the chemisorption was dominant throughout the adsorption process. Apart from the excellent adsorption properties of Rb+ and Cs+ from aqueous solution, both BCA@STS and CBCA@STS can be used for the adsorption of Rb+ and Cs+ from the brine, and the maximum adsorption rate is up to almost 100%, showing promising application for extracting of Rb+ and Cs+.

Preparation of ETS-10 Microporous Phase Pellets with Color Change Properties.

The main scope of the present work is to synthesize pH-responsive Engelhard titanium silicate (ETS)-10 phase crystalline pellets through the smart modification of a synthetic process which was previously applied to the preparation of other phases. The original preparative method, which envisages the use of the same initial synthesis as a binder for the preparation of pellets, was modified by adding an appropriate pH indicator to a number of systems subject to this investigation. It should be noted that the modified process was never before used to give access to pH-responsive ETS-10 phase pellets, and it is disclosed here for the first time. The study started from the definition of the best experimental conditions, which were optimized by analyzing the effects of temperature and system composition. The addition of the pH indicator did not alter the physicochemical characteristics and reactivity of the system. The pH-responsive ETS-10 phase crystalline pellets were characterized by an adequate mechanical strength and by a high capability to change color. The latter aspect can be particularly useful when this material is used in catalytic processes whose performance is strictly dependent on the pH value. The amount of gel used, as well as the working temperature, were the main critical parameters to be controlled during the preparation of pH-responsive ETS-10 phase crystalline pellets. The pellets were fully characterized by X-ray diffraction in order to investigate and identify the possible phases, and by using a hardness tester to measure the compressive strength. Finally, toning tests were performed.

Performance of PATC-PDMDAAC Composite Coagulants in Low-Temperature and Low-Turbidity Water Treatment.

A novel composite was synthesized by using flocculant polyaluminum titanium silicate chloride (PATC) and poly(diallyldimethylammonium chloride) (PDMDAAC) monomers to treat low-temperature and low-turbidity water. The structure and physicochemical properties of PATC-PDMDAAC were analyzed by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis/differential scanning calorimetry (TG/DSC), X-ray diffraction spectroscopy (XRD), and scanning electron microscopy–energy dispersion spectrum (SEM-EDS). The compound flocculant produced new functional groups exhibiting great thermal stability, and the complex chemical reaction between the two monomers generated new substances with reticular structures. Coagulation performance results showed that the PATC-PDMDAAC had an organic and inorganic ratio of 0.15 and exhibited excellent removal efficiency at pH 9.0, dosage of 1.80 mg/L, sedimentation time of 40 min, and a stirring speed of 110 r/min. The optimal treatment efficiency reduced the turbidity to 0.56 NTU (Nephelometric Turbidity Unit). The removal rates of TOC (Total Organic Carbon) and UV254 (Ultraviolet 254) were 62.18% (from 7.23 mg/L to 2.734 mg/L) and 99.99% (from 10 mg/L to 0.001 mg/L). The 3D fluorescence, zeta potential and kinetic analysis in the flocculation process indicated that coagulant electroneutralization and adsorption bridge in a slightly alkaline environment played a dominant role, and a sufficient and effective collision occurred between the coagulant and particulate matter under the optimal dosage. Lastly, PATC-PDMDAAC has more advantage than conventional flocculants in the treatment of low-temperature and low-turbidity water in the Xiangjiang River.

Potentiality of uranium extraction from acidic leach liquor by polyacrylamide-acrylic acid titanium silicate composite adsorbent

ABSTRACTUranium has an important role in nuclear reactors and nuclear power supply. In this study, the recovery of uranium from sulphate leach liquor was investigated using synthesised poly (acrylamide-acrylic acid)-titanium silicate (P-(AM-AA)-TS) composite as an adsorbent. The polymer composite was prepared by gamma radiation polymerisation of acrylic acid (AA monomer), polyacrylamide (PAM, template), bisacrylamide (BAA, crosslinker) and titanium silicate as an adsorbent for uranium recovery. The (P-(AM-AA)-TS) was studied for recovery of uranium from sulphate leach liquor. Different reaction parameters affecting the uranium sorption were investigated, namely pH, contact time, temperature, uranium concentration and a dose of the adsorbent to sulphate leach liquor. Adsorption per cent of uranium reached 98.6% from leach liquor of pH 2.5; initial uranium concentration is 700 mg/L at room temperature using 0.1 g P-(AM-AA)-TS adsorbent for 120 min. The theoretical studies showed that the batch isotherm fits with the Langmuir model. The adsorption capacity of the adsorbent reached 64.1 mg/g based on the Langmuir model.

Ultrafast-laser vitrification of laser-written crystalline tracks in oxide glasses

We report a method of femtosecond laser-induced vitrification of crystalline tracks laser-written in glasses with different crystallization ability including lanthanum borogermanage, barium titanium silicate and lithium niobium silicate glasses. We have found that crystalline tracks consisting of nonlinear optical LaBGeO5 and BaTi2Si2O8 phases corresponding to glass-forming compositions could be readily amorphized by the femtosecond beam, whereas the laser-induced vitrification of a track consisting of LiNbO3 crystalline phase possessing a non-glass-forming composition is more complicated but also possible. The suggested technique provides reversibility of femtosecond laser-induced space-selective crystallization of glasses and thus extends the functionality of the direct laser writing of crystal-in-glass architectures that is important for the fabrication of novel integrated optical components and devices.

Removal of 1,4-dioxane by titanium silicalite-1: Separation mechanisms and bioregeneration of sorption sites

1,4-Dioxane is a probable carcinogen and trace contaminant that is difficult to remove from water because of its high solubility and low volatility. Removal of 1,4-dioxane from aqueous solutions by a set of potential adsorbents was investigated using batch experiments that revealed Titanium Silicate-1 (TS-1) as a high-capacity adsorbent (85.17 mg/g) with rapid kinetics (2 min equilibration time). The specific adsorption mechanisms at the molecular level were investigated using multiple approaches including FTIR spectra and molecular dynamics simulation of 1,4-dioxane adsorption on TS-1, which imply that the shape and size of 1,4-dioxane fits tightly into the hydrophobic straight channels of TS-1 with a diameter of 0.56 nm, and thus TS-1 provides strong van der Waals attraction within the channels. Additionally, 1,4-dioxane-water complexation was observed to connect to the frame oxygens of TS-1 via hydrogen bonds inside the channels. The calculated adsorption free energy of 1,4-dioxane was between −24.59 and −27.17 kJ/mol, which was consistent with the value of −24.89 kJ/mol derived from the adsorption isotherms at 298 K. The strong adsorption competition from nonpolar compounds 1,1,1-trichloroethane (TCA) and benzene onto TS-1 further confirmed that the adsorption was attributed to a combined mechanism of host-guest interactions including van der Waals interactions, hydrophobic interactions, and hydrogen bonding. Furthermore, 1,4-dioxane-loaded TS-1 was found to be efficiently regenerated by an enriched bacterial consortium (BD1) with recovery efficiencies for three cycles of 88.2%, 96.47% and nearly 100%, suggesting that TS-1 holds promise as a cost-effective renewable absorbent for eliminating hydrophilic organics from contaminated water supplies.

Titanium Silicates Precipitated on the Rice Husk Biochar as Adsorbents for the Extraction of Cesium and Strontium Radioisotope Ions

The aim of the work was the development of cheap and effective adsorbents based on titanium silicates deposited on the products of thermochemical processing of rice husk to extract cesium and strontium radioisotopes from aqueous media. Synthesis of adsorbents was carried out using the cheapest and widely used titanium water-soluble reagent, titanium sulfate (an intermediate product of white rutile pigment production), as feedstock. After treatment with titanium sulfate and neutralization, hydrothermal treatment was carried out in various ways. The traditional method of processing in an autoclave was used, as well as the blowing at different temperatures by steam. The distribution coefficients and the adsorption capacity for cesium and strontium ions on these sorbents were studied. Along with the chemical composition of adsorbents obtained by those ways, the type and the temperature of hydrothermal treatment also affected the adsorption properties. It was found that the adsorbent obtained by hydrothermal treatment in an autoclave has the highest degree of cesium ions extraction (Kd = 27,500). The highest degree of strontium ions extraction (Kd = 2,095,000) has an adsorbent obtained by hydrothermal treatment with water vapor blowing.

The Direct Synthesis of H2O2 Using TS‐1 Supported Catalysts

AbstractIn this study we show that using AuPd nanoparticles supported on a commercial titanium silicate (TS‐1) prepared using a wet co‐impregnation method it is possible to produce hydrogen peroxide from molecular H2 and O2 via the direct synthesis reaction. The effect of Au: Pd ratio and calcination temperature is evaluated as well as the role of Pt addition to the AuPd supported catalysts. The effect of Pt addition to AuPt nanoparticles is observed to result in a significant improvement in catalytic activity and selectivity to hydrogen peroxide with detailed characterisation indicating this is a result of selectively tuning the ratio of Pd oxidation states.

Research on Gas-Phase Direct Epoxidation of Propylene by Nanosized Gold Catalysts

One-step synthesis of propylene oxide from propylene in gas phase in the presence of hydrogen and oxygen is an environmentally friendly and energy-saving ideal reaction, which has important research value. The gold catalyst prepared by deposition and precipitation method has the advantages of small particle size, high dispersity and good activity. It is used for epoxidation of propylene in gas phase. The selectivity meets the requirements of industrialization. However, how to improve the conversion of propylene is still the focus of research. The effect of doping on the gas phase epoxidation of propylene is obvious. The purpose of this paper is to synthesize titanium silicate molecular sieves with composite structure and corresponding nano-gold catalysts by combining the advantages of high stability, weak surface acidity, large specific surface area, large pore size and pore volume of microporous titanium cinnamon molecular sieves.

Fabrication of Microspheres by Nano-TS-1 Crystals via a Spray-Forming Process: From Screening to Scale-up.

The spray-forming process of the nano-titanium silicalite (TS-1) zeolite was investigated and optimized in the lab in order to obtain materials with microsphere morphology and superior catalytic activity in cyclohexanone ammoximation on the industrial scale. The effects of spray-forming parameters, such as the state of the TS-1 raw material, load ratio, solid content, binder content, and calcination temperature, on the physicochemical and catalytic properties of TS-1 microspheres were investigated in detail. It was interesting to find that the shape of the spray-forming sample formed by wet powders was more intact than the sample formed by dried powders. Furthermore, the spray-forming process was successfully scaled up to a large spray device (LGZ-1000) according to the similarity principle of load ratio, and the shape of the TS-1 microspheres was as perfect as the spray-forming samples in the lab. The similarity principle of the load ratio for the spray-forming of titanium silicate was established and verified for the first time. The spray-forming TS-1 microspheres produced in the industry were used in cyclohexanone ammoximation, and ketone conversion and oxime selectivity were as high as 99.9 and 99.4%, respectively.

Cooperative Effects between Hydrophilic Pores and Solvents: Catalytic Consequences of Hydrogen Bonding on Alkene Epoxidation in Zeolites.

Hydrophobic voids within titanium silicates have long been considered necessary to achieve high rates and selectivities for alkene epoxidations with H2O2. The catalytic consequences of silanol groups and their stabilization of hydrogen-bonded networks of water (H2O), however, have not been demonstrated in ways that lead to a clear understanding of their importance. We compare turnover rates for 1-octene epoxidation and H2O2 decomposition over a series of Ti-substituted zeolite *BEA (Ti-BEA) that encompasses a wide range of densities of silanol nests ((SiOH)4). The most hydrophilic Ti-BEA gives epoxidation turnover rates that are 100 times larger than those in defect-free Ti-BEA, yet rates of H2O2 decomposition are similar for all (SiOH)4 densities. These differences cause the most hydrophilic Ti-BEA to also give the highest selectivities, which defies conventional wisdom. Spectroscopic, thermodynamic, and kinetic evidence indicate that these catalytic differences are not due to changes in the electronic affinity of the active site, the electronic structure of Ti-OOH intermediates, or the mechanism for epoxidation. Comparisons of apparent activation enthalpies and entropies show that differences in epoxidation rates and selectivities reflect favorable entropy gains produced when epoxidation transition states disrupt hydrogen-bonded H2O clusters anchored to (SiOH)4 near active sites. Transition states for H2O2 decomposition hydrogen bond with H2O in ways similar to Ti-OOH reactive species, such that decomposition becomes insensitive to the presence of (SiOH)4. Collectively, these findings clarify how molecular interactions between reactive species, hydrogen-bonded solvent networks, and polar surfaces can influence rates and selectivities for epoxidation (and other reactions) in zeolite catalysts.

Synthesis of Azoxybenzenes by Selective Oxidation of Anilines on Titanium Silicate Molecular Sieves

Synthesis of Azoxybenzenes by Selective Oxidation of Anilines on Titanium Silicate Molecular Sieves

Synthesis of a high-surface area V2O5/TiO2-SiO2 catalyst and its application in the visible light photocatalytic degradation of methylene blue.

In the present study, we synthesized several high-surface area V2O5/TiO2–SiO2 catalysts (vanado titanium silicate, VTS). The synthesized materials were characterized by PXRD, FE-SEM/EDAX, TEM, FTIR, UV-Vis, XPS, fluorescence and photocatalytic activity studies. The small-angle powder X-ray diffraction pattern shows that the 110 and 200 planes are merged to become a single broad peak. Field-emission scanning electron microscopy shows that the titanosilicate is spherical in shape and V2O5 has a hexagonal rod-shaped morphology. The presence of various metal ions, such as V, Ti, Si and O, was observed by energy dispersive X-ray analysis and X-ray photoelectron spectroscopy. The transmission electron microscopy image shows clear hexagonal mesoporous fringes with V2O5 distribution. The BET surface area analysis shows that the VTS catalysts have higher surface areas than pure V2O5. Fourier transform infrared spectroscopic analysis shows the presence of Ti4+ ions connected to the silanol groups. The bandwidths of pure titanosilicate, V2O5 and their composites were calculated from their diffuse reflectance ultraviolet-visible spectra. The bandwidth was tuned by heterojunctions in the studied catalysts. The photoluminescence spectra of the VTS catalysts show a distinct behaviour as compared to those of the pure components. The photocatalytic activity of methylene blue degradation was determined with pure constituents and catalysts. VTS-1 (TS and VO weight ratio 2 : 1) shows higher conversion than other catalysts, pure titanosilicate and V2O5. This is probably due to the heterojunctions and higher surface area in VTS-1. Kinetic studies reveal that direct sunlight shows higher activity than pure visible light. A plausible physical and chemical mechanism for the photocatalytic activity is proposed.