Incorporation Of Ti Research Articles

Mutual Effect of Oxide Peg Growth and Reactive Element Distribution in Ti-doped CoNiCrAlY Alloys

CoNiCrAl alloys are widely employed as a high temperature resistant material in thermal barrier coating (TBC) systems. In such materials, the adherence between the thermally grown oxide (TGO) Al2O3 scale and the alloy is strengthened by oxide pegs formed by dispersed oxide addition or the oxidation of doped reactive elements. In this study the addition of Ti as the reactive element to a CoNiCrAlY alloy has been addressed. We investigated the mutual effects between Ti and the oxide pegs in alloy samples that had been subjected to a cyclic oxidation process. The alloy with a higher Ti content exhibited a uniformly fine β-phase and fewer voids at the scale/alloy interface, the scale growth rate was lower for Ti-containing alloys. In addition, the formation and growth of oxide pegs led to an irregular distribution of Ti in the scale and at the scale/alloy interface, which resulted in local variations in the features of the scale, with fewer voids and a thinner scale at the sites that are far from the oxide pegs. Meanwhile, the incorporation of Ti to the Y-rich oxide led to an increase in the bonding strength between the peg core and the Al2O3 sheath.

Influence of Ti Incorporation to Bimetallic Mesoporous Carbon in the Production of 2,5-Dimethylfuran from Biomass Derivatives

Monometallic and bimetallic supported catalysts were developed to produce 2,5-dimethylfuran (DMF) trough hydrogenolysis of 5-(hydroxymethyl)furfural (HMF). Detailed physicochemical characterization was done to understand structure–activity correlation. Through a series of experiments and comparatives tests, the synergistic effect among Pt, Ir, and Ti incorporated in the support was investigated. Results revealed that using the titanium contained ordered mesoporous carbon, synthesized by a novel technique, high selectivity to DMF was achieved. In the case of the best catalyst PtIr-TiC, the good activity and excellent selectivity to the desired product DMF (98% yield) was related to the high hydrogenating capacity of the bimetallic sites, the acid support characteristics and the high metal nanoparticles dispersion achieved on the mesoporous titanium modified carbon support.Graphic Abstract

Electronic, elastic, and topological behavior of MgH2, MgTiH4, and TiH2 under pressure

This paper studies the elastic, structural, electronic, and topological behaviors of α-MgH2, β-MgH2, MgTiH4, and TiH2 under pressure by resorting to DFT-GGA’s first principle via FPLAPW-WIEN2K, ElaStic1.0, and Critic2 software. Pressure effects are studied from strain vectors generating a linear volume variation with strain. Important structural changes by the effect of pressure are evidenced. The highest strength at hydrostatic deformation was reached by TiH2; and the lowest, by α-MgH2. The elastic constants and moduli for each hydride studied showed agreement with the results reported in the literature. The TiH2 cubic lattice is shown to be structurally unstable. Hydrides showed more stability than pure crystals. The tetragonal structure of MgH2 was confirmed as more stable than its respective cubic structure; and the cubic structure of TiH2, even more so than that of the Mg hydrides, independently of their crystalline structure. Hydrides with a cubic structure showed a ductile condition, whereas those with a tetragonal structure showed a fragile one. α-MgH2 revealed an insulating character. Other hydrides studied showed a conductive character. The topology of charge density and potential energy density establishes a marked difference between the topological classes and the number of critical points (CPs) for both cubic (β-MgH2, TiH2) and tetragonal structures (α-MgH2, MgTiH4), the multiplicity of these being markedly superior in the former. The bonding character in general is covalent in the CP nucleus and both closed-layered and hydrogen-bonded in the other CPs, except in the Ti-H CP bond of the compressed structures, which bears an ionic character, unlike that of expanded structures. The incorporation of Ti to MgH2 weakens the Mg-H bond, which in turn favors the kinetics of dehydrogenation in MgTiH4.

Effects of Ti and Al incorporation on the performance of FSM-16 supported nickel catalyst in dry reforming of methane

Effects of Ti and Al incorporation on the performance of FSM-16 supported nickel catalyst in dry reforming of methane

Incorporation of Ti in epitaxial Fe2TiO4 thin films

The titanomagnetites (Fe2−x Ti x O4, x ⩽ 1) are a family of reducible spinel-structure oxides of interest for their favorable magnetic, catalytic, and electrical transport properties. To understand the stability of the system during low temperature deposition, epitaxial thin films of Fe2TiO4 were deposited by molecular beam epitaxy (MBE) on MgO(001) at 250–375 °C. The homogeneous incorporation of Ti, Fe valence state, and film morphology were all found to be strongly dependent on the oxidation conditions at the low substrate temperatures employed. More oxidizing conditions led to phase separation into epitaxial, faceted Fe3O4 and rutile TiO2. Less oxidizing conditions resulted in polycrystalline films that exhibited Ti segregation to the film surface, as well as mixed Fe valence (Fe3+, Fe2+, Fe0). A narrow window of intermediate oxygen partial pressure during deposition yielded nearly homogeneous Ti incorporation and a large fraction of Fe2+. However, these films were poorly crystallized, and no occupation of tetrahedral sites in the spinel lattice by Fe2+ was detected by x-ray magnetic circular dichroism at the Fe L-edge. After vacuum annealing, a small fraction of Fe2+ was found to occupy tetrahedral sites. Comparison of these results with previous work suggests that the low temperature deposition conditions imposed by use of MgO substrates limits the incorporation of Ti into the spinel lattice. This work suggests a path towards obtaining stoichiometric, well-crystallized Fe2TiO4 by MBE by utilizing high substrate temperature and low oxygen partial pressure during deposition on thermally stable substrates.

Synthesis of Low Cost Titanium Silicalite-1 Zeolite for Highly Efficient Propylene Epoxidation.

Developing an effective and low-cost system to synthesize titanium silicalite-1 (TS-1) zeolite is desirable for a range of industrial applications. To date, the poor catalytic activity of the synthesized zeolite due to the low amount of framework titanium and large crystal size is the main obstacle limiting the widespread application of this material. Moreover, a large amount of wastewater is often produced by the existing synthesis process. Herein, a green and sustainable route for synthesizing small-crystal TS-1 with a high fraction of framework Ti was demonstrated via a seed-assisted method using a tetrapropylammonium bromide (TPABr)-ethanolamine hydrothermal system. The influence of the synthesis conditions on the physicochemical properties and catalytic activities of TS-1 was investigated. With the assistance of nanosized S-1 seeds, the incorporation of Ti into the framework of TS-1 was promoted, and the crystallization rate was effectively accelerated. After alkaline etching, the obtained hierarchical TS-1 had higher catalytic activity towards propylene epoxidation with an extremely high turnover frequency of 1,650 h−1. Furthermore, the mother liquid during the hydrothermal reaction could be reused for the next synthesis procedure. Consequently, utilization ratios of both ethanolamine and TPABr exceeding 95% were achieved by recycling the mother liquid. This low-cost approach for reducing wastewater could be easily scaled up to provide a promising synthesis method for the industrial production of TS-1 and other topological zeolites.

Complementary Effect of Ti and Ni Incorporation in Improving the Electrochemical Performance of a Layered Sodium Manganese Oxide Cathode for Sodium-Ion Batteries

Complementary Effect of Ti and Ni Incorporation in Improving the Electrochemical Performance of a Layered Sodium Manganese Oxide Cathode for Sodium-Ion Batteries

Growth of Ba–O ultrathin films on Pt(1 1 1) followed by Ti incorporation to prepare oxide crystalline approximants and quasicrystals

In this study, three different precursor Ba–O films on Pt(111) are characterized and the oxide crystalline approximant (OCA) and oxide quasicrystal (OQC) films are prepared by annealing after Ti deposition on the films. The prepared Ba–O ultra-thin films are BaO(100)–(√2×√2)R3°:Pt(111), Ba–O:Pt(111)–(2 × 2) and Ba–O:Pt(111)–(√13×√13)R13.9°, as determined using scanning tunneling microscopy, low-energy electron diffraction, and X-ray photoelectron spectroscopy. The phase transformation from an OCA film to an OQC film likely follows the mechanism where Ti is reduced and its surface atomic density decreased, while Ba is oxidized. The schematic structural models of the OCA film as Ba4Ti4O10 and the OQC film as Ba12Ti5O12, where the Ba atoms form a cluster tiling, are proposed.

Efficient transformation of cyclohexanone to ε-caprolactone in the oxygen-aldehyde system over single-site titanium BEA zeolite

Ti x SiBEA zeolites prepared by a two-step post-synthesis method are applied in the liquid-phase Baeyer-Villiger oxidation of cyclohexanone to ε-caprolactone in the oxygen-aldehyde system. Such method of ε-caprolactone synthesis offers the application of milder reaction conditions with the catalytic system which transforms cyclic ketones into lactones in the presence of molecular oxygen and aldehyde. They are the source of in situ peracid formation. The Ti incorporation into SiBEA involves the formation of Ti(IV) (OSi) 4 as main species and small numbers of Ti(III) (OSi) 3 –O(H)–Si sites having Brønsted and Lewis acid properties. The acidity is a key factor for efficient transformation of cyclohexanone to ε-caprolactone in the BV oxidation depending on the titanium oxidation state and environment. Among all of the studied catalysts, the highest catalytic activity is observed for Ti 2.0 SiBEA zeolite. The active catalyst of the studied BV oxidation reaction is bi-functional, possessing both the acidic and redox properties, catalyzing different reaction stages. • The incorporation of Ti into the SiBEA framework evidenced by FTIR and NMR. • DR UV–vis and XPS showed the presence of framework tetrahedral Ti(IV). • Ti(IV) (OSi) 4 sites appeared as main redox centres. • Ti(III) (OSi) 3 –O(H)–Si sites possessed both Brønsted and Lewis acid properties. • The Ti x SiBEA catalysts applied in BV oxidation reaction have bifunctional character.

Microstructural and crystallographic effects of sol-gel synthesized Ti-doped UO2 sintered under reducing conditions

Titanium (Ti)-doped UO 2 microspheres of three different Ti concentrations (1000, 2000, and 4000 wppm) were synthesized using an internal gelation process. The microspheres were pressed into pellets, and a two-step heat treatment was applied to form monolithic cylindrical pellets with high densities (≥95%TD). Microstructure of these samples consisted of equiaxed grains with >300% increase in average grain size compared to the undoped UO 2 pellets. Secondary Ti-rich chemical phases corresponding to a liquid eutectic formed during sintering were observed at grain boundaries of UO 2 for samples doped with 4000 wppm Ti. These Ti-rich chemical phases were not observed in 1000 or 2000 wppm Ti samples at microscale using electron microscopy investigations. The 0.02–0.04% lower lattice parameter values for the Ti-doped UO 2 samples compared to the undoped UO 2 confirms the incorporation of Ti into the UO 2 lattice.

Active Brazing of Alumina and Copper with Multicomponent Ag-Cu-Sn-Zr-Ti Filler

The study was designed to investigate the synergic effect of Ti and Sn in the active metal brazing of Al2O3 ceramic to copper brazed, using the multicomponent Ag-Cu-Zr filler alloy. Numerous fine and hexagonal-shaped rod-like ternary intermetallic (Zr, Ti)5Sn3 phase (L/D = 5.1 ± 0.8, measured in microns) were found dispersed in the Ag-Cu matrix of Ag-18Cu-6Sn-3Zr-1Ti alloy, along with the ternary CuZrSn intermetallic phases. An approximate 15° reduction in contact angle and 3.1 °C reduction in melting point are observed upon the incorporation of Ti and Sn in Ag-18Cu-3Zr filler. Interestingly, the interface microstructure of Al2O3/Cu joints brazed by using Ag-18Cu-6Sn-3Zr-1Ti filler shows a double reaction layer: a discontinuous Ti-rich layer consisting of (Cu, Al)3(Ti, Zr)3O, TiO, and in-situ Cu-(Ti, Zr) precipitates on the Al2O3 side and continuous Zr-rich layer consisting of ZrO2 on the filler side. The shear strength achieved in Al2O3/Cu joints brazed with Ag-18Cu-6Sn-3Zr-1Ti filler is 31% higher, compared to the joints brazed with Ag-18Cu-6Sn-3Zr filler. Failure analysis reveals a composite fracture mode indicating a strong interface bonding in Al2O3/Ag-18Cu-6Sn-3Zr-1Ti filler/Cu joints. The findings will be helpful towards the development of high entropy brazing fillers in the future.

Improving Ti Incorporation into the BEA Framework by Employing Ethoxylated Chlorotitanate as Ti Precursor: Postsynthesis, Characterization, and Incorporation Mechanism

The liquid–solid postsynthetic method is commonly used in the preparation of metal-containing zeolites, for example, Ti-β (BEA) zeolite. This paper reports a facile and Ti incorporation improved li...

Titanium-modified MCM-41 molecular sieves as efficient supports to increase the hydrogenation abilities of NiMoS and CoMoS catalysts

Ti modified MCM-41-supported NiMo and CoMo catalysts and their respective Ti free reference catalysts were prepared, characterized, and tested for the hydrodesulfurization reactions. The samples were synthesized by well-known procedures, such as liquid crystal templating and successive impregnation method for the supports and catalysts, respectively. Ti precursor was directly incorporated into the micellar solution before adding the silica precursor at different molar Si/Ti ratios (x=75 and 50). Fourier transform infrared spectroscopy, solid-state 29Si-nuclear magnetic resonance, small- and wide-angle X-ray diffraction, and nitrogen physisorption were used as characterization techniques. Four sulfided catalysts were also characterized by high-resolution transmission electron microscopy. The catalysts showed important increases in the reaction rates during both thiophene and dibenzothiophene hydrodesulfurization when the support was structurally modified with Ti-atoms. The samples supported on Ti-MCM-41(75) presented a higher activity than those supported on Ti-MCM-41(50), and they were superior to their respective Si-MCM-41-supported NiMoS and CoMoS catalysts, even NiMoTiM75 and CoMoTiM75 catalysts presented better performance compared to the conventional NiMo/Al2O3 and CoMo/Al2O3 catalysts in the DBT hydrodesulfurization. Ti incorporation also enhanced the selectivities to the hydrogenated products, which could be beneficial to destabilize refractory S-containing molecules.

Improved Performance of InGaZnO Thin-Film Transistor With Ti Incorporation Into La2O3 Gate Dielectric

The effects of Ti incorporation in La2O3 gate dielectric on the electrical characteristics of amorphous InGaZnO thin-film transistor are studied. Compared to the control sample with La2O3 gate dielectric, the device performance can be significantly improved with an appropriate Ti dose. Accordingly, the sample with a Ti/(Ti+La) ratio of 6.7% presents a high saturation mobility of 28.1 cm2V−1s−1, small subthreshold slope of 0.17 V/dec, large on/off current ratio of $7.2\times 10$ 7, and acceptable hysteresis. We attribute such an improvement to the passivation of the defect states at/near the La2O3/InGaZnO interface as well as the enhancement of moisture resistance of La2O3 film due to Ti incorporation. However, excessive Ti incorporation leads to device degradation, which is due to more oxygen vacancies generated in gate dielectric.

Effect of alloying elements on thermal stability of nanocrystalline Al alloys

Abstract The effect of incorporating limited-diffusivity elements such as Fe and Ti on thermal stability of the nanocrystalline Al alloy was investigated. Al−10wt.%Fe and Al−10wt.%Fe−5wt.%Ti alloys were fabricated. The initial mixtures of powders were milled for 100 h in vacuum. The bulk samples were fabricated from the milled powders in a high frequency induction heat sintering (HFIHS) system. The milled powders and the bulk sintered samples were characterized by X-ray diffraction (XRD), Vickers microhardness, field emission scanning electron microscopy (FESEM-EDS) and transmission electron microscopy (TEM). The observations indicated that Fe and Ti were completely dispersed in the matrix to form a supersaturated solid solution (SSSS) with Al. Additionally, the inclusion of alloying elements led to an increase in hardness and yield strength of the alloy by 127% and 152%, respectively. The elevated temperature compression tests were carried out to evaluate the thermal stability of the alloys. The Al−10wt.%Fe−5wt.%Ti alloy revealed the optimum thermally stable behavior of the three alloys studied. The incorporation of Fe and Ti improved the thermal stability of the developed alloys through inhibiting the grain growth, hindering dissolution and growth of second phases (such as Al13Fe4 and Al13Ti), and forming a stable solid solution.

Aerogel Re/Pd-TiO2/SiO2 and Co/Mo-Al2O3/SiO2 catalysts for hydrodesulphurisation of dibenzothiophene and 4,6-dimethyldibenzothiophene

Re/Pd-TiO2/SiO2 and Co/Mo-Al2O3/SiO2 aerogel catalysts were synthesized using sol-gel method and supercritical drying in excess solvent, and investigated in the hydrodesulphurisation (HDS) of dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT). The influence of supercritical drying on the final catalytic properties of the materials was determined by parallel synthesis of aerogels and xerogels for Re/Pd-TiO2/SiO2 catalysts. The sol-gel method and supercritical drying were found to result in amorphous aerogels with relatively high degree of uniformity, of both supports and active phases. Corresponding xerogels were found to be similar to aerogels in terms of composition and structure, but characterized by lower specific surface areas. Catalytic activity of Co/Mo-Al2O3/SiO2 aerogel catalysts in HDS of DBT and 4,6-DMDBT has shown no major improvement in comparison to conventional Co/Mo catalyst. On the other hand, Re/Pd-TiO2/SiO2 aerogels, obtained with the addition of mesitylene or without it, achieved 70 % and 64 % higher conversion of 4,6-DMDBT than conventional Co/Mo catalyst, respectively. Increased catalytic activity can be attributed to well dispersed Re and Pd active phases across the catalyst structure, good incorporation of Ti within silica matrix, increased mesopore volumes and high specific surface areas.

Rippite, K2(Nb,Ti)2(Si4O12)O(O,F), a New K-Nb-Cyclosilicate from Chuktukon Carbonatite Massif, Chadobets Upland, Krasnoyarsk Territory, Russia

Rippite K2(Nb,Ti)2(Si4O12)(O,F)2, a new K-Nb-cyclosilicate, has been discovered in calciocarbonatites from the Chuktukon massif (Chadobets upland, SW Siberian Platform, Krasnoyarsk Territory, Russia). It was found in a primary mineral assemblage, which also includes calcite, fluorcalciopyrochlore, tainiolite, fluorapatite, fluorite, Nb-rich rutile, olekminskite, K-feldspar, Fe-Mn–dolomite and quartz. Goethite, francolite (Sr-rich carbonate–fluorapatite) and psilomelane (romanèchite ± hollandite) aggregates as well as barite, monazite-(Ce), parisite-(Ce), synchysite-(Ce) and Sr-Ba-Pb-rich keno-/hydropyrochlore are related to a stage of metasomatic (hydrothermal) alteration of carbonatites. The calcite–dolomite coexistence assumes crystallization temperature near 837 °C for the primary carbonatite paragenesis. Rippite is tetragonal: P4bm, a = 8.73885(16), c = 8.1277(2) Å, V = 620.69(2) Å3, Z = 2. It is closely identical in the structure and cell parameters to synthetic K2Nb2(Si4O12)O2 (or KNbSi2O7). Similar to synthetic phase, the mineral has nonlinear properties. Some optical and physical properties for rippite are: colorless; Mohs’ hardness—4–5; cleavage—(001) very perfect, (100) perfect to distinct; density (meas.)—3.17(2) g/cm3; density (calc.)—3.198 g/cm3; optically uniaxial (+); ω = 1.737-1.739; ε = 1.747 (589 nm). The empirical formula of the holotype rippite (mean of 120 analyses) is K2(Nb1.90Ti0.09Zr0.01)[Si4O12](O1.78OH0.12F0.10). Majority of rippite prismatic crystals are weakly zoned and show Ti-poor composition K2(Nb1.93Ti0.05Zr0.02)[Si4O12](O1.93F0.07). Raman and IR spectroscopy, and SIMS data indicate very low H2O content (0.09–0.23 wt %). Some grains may contain an outermost zone, which is enriched in Ti (+Zr) and F, up to K2(Nb1.67Ti0.32Zr0.01)[Si4O12](O1.67F0.33). It strongly suggests the incorporation of (Ti,Zr) and F in the structure of rippite via the isomorphism Nb5+ + O2− → (Ti,Zr)4+ + F1−. The content of a hypothetical end-member K2Ti2[Si4O12]F2 may be up to 17 mol. %. Rippite represents a new structural type among [Si4O12]-cyclosilicates because of specific type of connection of the octahedral chains and [Si4O12]8− rings. In structural and chemical aspects it seems to be in close with the labuntsovite-supergroup minerals, namely with vuoriyarvite-(K), K2(Nb,Ti)2(Si4O12)(O,OH)2∙4H2O.

Ion Transport in Chromite Spinels for Multivalent Battery Applications

Multivalent-ion batteries, based on the reversible reactivity of metal cations Mn+ (where n ≥ 2), offer great promise to supersede the current state-of-the-art Li-ion battery and provide a step change in energy storage capability. Oxide materials based on the spinel structure, AB2O4 (where A is the diffusing ion, M2+) have previously demonstrated potential to be high capacity, high voltage cathode materials for such batteries, with a 3D network of M2+ diffusion channels to facilitate ion transport.1–3 In particular, the MgCr2O4 spinel has been of interest due the predicted high electrochemical potential (~3.5 V) of Cr3+/Cr4+ vs. Mg/Mg2+.2 However, reversible Mg2+ intercalation kinetics has often proven to be poor in such systems, with large overpotentials observed on charge and discharge.3,4 The origin of these kinetic barriers is still poorly understood, where it is postulated that poor Mg2+ diffusion through the oxide lattice, sluggish ion transfer between the electrode and electrolyte, or resistive surface layers from electrolyte decomposition products may be responsible.In this presentation, we discuss the application of solid-state impedance spectroscopy to a library of doped spinel compounds, M1−x Cr2−2x Ti2x O4, where M = Mg or Zn, to elucidate the diffusion behavior of Mg2+ and Zn2+ in these systems. We reveal that incorporation of Ti had significant impact on the impedance behavior of the materials. As both M2+ and e− were found to diffuse in these materials, they displayed mixed ionic and electronic conductor (MIEC) behavior.5,6 This presentation includes the development and interpretation of a new physical model to describe the motion of M2+ and e− in the M1−x Cr2−2x Ti2x O4 spinel, which was necessary to accurately describe their diffusive behavior and extract their conductivities. This study therefore represents a breakthrough in the understanding of M2+ motion in these systems, and provides a methodological framework for further studies of other electrode chemistries.

Effect of the titanium incorporation method on the morphology and HDS activity of supported ternary Ni–Mo–W/SBA-16 catalysts

A series of trimetallic Ni–Mo–W catalysts supported on cubic mesoporous silica (SBA-16) modified with Ti were prepared with the aim to study the effect of Ti incorporation method (sol-gel against pore volume post-synthesis impregnation) on the physical and chemical properties of the synthetized materials. The catalytic behavior of the sulfided catalysts was evaluated in the reaction of hydrodesulfurization (HDS) of dibenzothiophene (DBT). The catalyst characterization by variety of techniques demonstrated that one-pot synthesis led to Ti ions incorporation into SBA-16 structure and an increase of acidity whereas the post-synthesis method led to formation of octahedral Ti species decorating support's surface. The catalytic behavior was closely linked with the characteristics of their oxide precursors. The catalysts prepared by sol-gel method demonstrated to be more effective toward S-removal from DBT than the catalyst modified by post-synthesis method. The initial HDS activity of the best NiMoW/S16–Ti catalyst doubled that of NiMoW/SBA-16 and a commercial NiMo/γ-Al2O3 which was linked with its better textural properties, acidity and adequate active phases dispersion. The main effect of the support modification with Ti was the enhancement of selectivity toward HYD route products. The best hydrogenation selectivity was archived by Ti incorporation via post-synthesis method which was linked to the formation of curved Mo(W)S2 layers having a large amount of “brim” HYD sites.

Oxidación de trans-2-hexen-1-ol empleando materiales mesoporosos

En este trabajo se estudió la reacción de oxidación del alcohol trans-2-hexen-1-ol utilizando catalizadores del tipo MCM-41. Para ello, se sintetizaron sólidos mesoporosos modificados con titanio que fueron caracterizados por área específica, DRX, UV-Vis RD, FTIR e ICP. Los sólidos mostraron buen ordenamiento estructural y elevada área específica. En el Ti-MCM-41 no se observaron óxidos metálicos, lo que sugiere una buena dispersión del Ti en la estructura. Los materiales sintetizados fueron evaluados catalíticamente en la reacción de oxidación de trans-2-hexen-1-ol en fase líquida, a 70 °C, utilizando H2O2 como oxidante y acetonitrilo como solvente. Los productos de reacción fueron identificados mediante CG-Masa y cuantificados empleando factores de respuesta. Los resultados mostraron que la incorporación de Ti en la matriz mesoporosa incrementó la conversión del sustrato de 1.69% mol a 4.29% mol. Luego, se evaluó el efecto producido al variar la relación molar sustrato/oxidante empleando Ti-MCM-41. Con una relación igual a 1, se logró una conversión máxima de 8.26% mol, con un rendimiento de 7.64% mol y una selectividad de 85.22% mol al 2-hexenal.