TS-1 Particles Research Articles

Tosoh reports Speciality Group results for fiscal 2021

Three titanosilicate zeolites were used as fillers for Mixed Matrix Membranes: (i) ETS-10, (ii) TS-1 having Si/Ti=100 and (iii) TS-1 using Si/Ti=25. Zeolite samples were characterized by X-Ray Diffraction, Scanning Electron Microscopy, Atomic Emission Spectroscopy, X-Ray Photoelectron Spectroscopy, and CO2 and CH4 adsorption isotherms. TS-1 particles showed a narrow size distribution ranging from 200 nm to 400 nm. In the case of ETS-10, the size distribution was broader ranging from 400 nm to 800 nm. Mixed Matrix Membranes were prepared using Matrimid® polyimide as continuous phase and filler loadings of 10, 20, and 30 wt%. Membranes were characterized by Thermogravimetric Analysis, Differential Scanning Calorimetry, and Scanning Electron Microscopy. The performances was measured at 8 bars of transmembrane pressure for CO2/CH4 mixed gases system at 50/50 vol/vol. concentration.Membranes using TS-1 (Si/Ti=25) as filler showed a maximum increase of 89.1% of CO2 permeability and 23.9% increase in separation factor. In the case of TS-1 (Si/Ti=100) only permeability increased significantly, with a maximum increase of 90.1%. Regarding the ETS-10 membranes, both permeability and separation factor increased slightly with respect to the reference polymeric membrane (22.5% in CO2 permeability and 7.8% in the separation factor). In conclusion, TS-1 (Si/Ti=25) is the most suitable filler for the use in Mixed Matrix Membranes for gas separation applications among the titanosilicate studied in this work.

Steam-Assisted in Situ Prepared TS-1 with Hierarchical Pores and Tunable Acid Sites Grown on Carbon Nanotubes Decorated Nickel Foam

The TS-1 particles grown on carbon nanotubes decorated nickel foam (denoted as MTS-1S) are successfully synthesized by a steam-assisted crystallization method that does not waste the gels and is mo...

In Situ Synthesis of TS-1 on Carbon Nanotube Decorated Nickel Foam with Ultrafine Nanoparticles and High Content of Skeleton Titanium

In this Article, TS-1 was successfully synthesized on carbon nanotubes decorated nickel foam via in situ strategy forming the monolithic TS-1 (MTS-1). To the best of our knowledge, situ synthesis of the MTS-1 has not been reported. Carbon nanotubes decorated nickel foam has many aggregated pores (confined pores formed in aggregated structure) and a large surface area, and TS-1 particles could be dispersed on the surface of CNT@NF. MTS-1 had the characteristics of ultrafine nanoparticle and high content of skeleton titanium. High absorptive property and electrostatic interaction between CNT@NF and gels could accelerate the crystallization rate. The TS-1 particles were solidly immobilized on the CNT@NF, and the conversion rate was almost constant even after multiple reactions. The catalyst is easy to separate from liquid products after reaction, which offers an economical application prospect.

Easily recoverable micron-sized silica-walled TS-1 colloidosomes: Preparation and application as liquid-phase alkene epoxidation catalysts

Ultrafine hierarchical TS-1 zeolite (<300nm) generally expresses eminent catalytic activity for liquid-phase alkene epoxidation, but encounters serious separation difficulties. Micron-sized silica-walled TS-1 colloidosomes, which were synthesized via an interfacial sol-gel method, can effectively resolve fine TS-1 zeolite separation problems. The interfacial sol-gel process involves construction of a stable W/O Pickering emulsion stabilized by fine TS-1 particles and alkali-catalyzed hydrolysis of silica precursor methyl-trimethoxysilane at the oil-water interface. The successful preparation of TS-1 colloidosome was verified by Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS). The prepared TS-1 colloidosome dimension is tailorable according to water-to-oil volume ratio (Rw/o) and ratio of TS-1 wt to oil volume (Rs/o). On the same time, X-ray diffraction patterns and UV–vis spectra disclosed that the interfacial sol-gel process had no effect on the MFI structure of hierarchical TS-1 particles. The catalytic results showed that the prepared TS-1 colloidosome was a very active and stable catalyst for liquid-phase alkene epoxidation reactions.

Study of different titanosilicate (TS-1 and ETS-10) as fillers for Mixed Matrix Membranes for CO2/CH4 gas separation applications

Three titanosilicate zeolites were used as fillers for Mixed Matrix Membranes: (i) ETS-10, (ii) TS-1 having Si/Ti=100 and (iii) TS-1 using Si/Ti=25. Zeolite samples were characterized by X-Ray Diffraction, Scanning Electron Microscopy, Atomic Emission Spectroscopy, X-Ray Photoelectron Spectroscopy, and CO2 and CH4 adsorption isotherms. TS-1 particles showed a narrow size distribution ranging from 200nm to 400nm. In the case of ETS-10, the size distribution was broader ranging from 400nm to 800nm. Mixed Matrix Membranes were prepared using Matrimid® polyimide as continuous phase and filler loadings of 10, 20, and 30wt%. Membranes were characterized by Thermogravimetric Analysis, Differential Scanning Calorimetry, and Scanning Electron Microscopy. The performances was measured at 8 bars of transmembrane pressure for CO2/CH4 mixed gases system at 50/50vol/vol. concentration.Membranes using TS-1 (Si/Ti=25) as filler showed a maximum increase of 89.1% of CO2 permeability and 23.9% increase in separation factor. In the case of TS-1 (Si/Ti=100) only permeability increased significantly, with a maximum increase of 90.1%. Regarding the ETS-10 membranes, both permeability and separation factor increased slightly with respect to the reference polymeric membrane (22.5% in CO2 permeability and 7.8% in the separation factor). In conclusion, TS-1 (Si/Ti=25) is the most suitable filler for the use in Mixed Matrix Membranes for gas separation applications among the titanosilicate studied in this work.

TS-1 molecular sieves filled polydimethylsiloxane membranes for ethanol/water separation via pervaporation

TS-1 molecular sieves were synthesized and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and UV–Vis spectroscopy. Results showed that the morphology, crystallinity, and purity of TS-1 were closely related to the Ti/Si ratio, crystallization time, crystallization temperature, and calcination time. The TS-1 particles were incorporated into polydimethylsiloxane to form mixed matrix membranes (MMMs), and these MMMs were first used to separate ethanol/water mixtures via pervaporation. The MMMs with 50 wt% TS-1 (Ti/Si ratio of 0.02) loading showed the highest separation factor of 14.1 for 5 wt% ethanol feed concentration at 50°C. POLYM. ENG. SCI., 56:583–589, 2016. © 2016 Society of Plastics Engineers

Synthesis of TS-1 on porous glass beads for catalytic oxidative desulfurization

Abstract Porous glass supported with titanium silicalite (TS-1) particles were successfully prepared and used for oxidative desulfurization (ODS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). Uniform-sized TS-1 particles were homogeneously dispersed on the surface of the porous glass beads. Effects of reaction duration, catalyst content, initial concentration, oxidant amount, and temperature on conversions were investigated. The prepared catalysts showed excellent catalytic performance. The optimal mole ratio of oxidant-to-DBT was 10 or 15. Complete conversion was obtained within 3 min at 343 K using catalyst with Ti content of 0.507 wt.%. Compared with other studies, the space–time yield was increased by one order of magnitude without any addition of solvent or metal nanoparticles. Experimental results and computer simulations revealed that the coordinated state of Ti species has a key role in the catalytic activity. Spent catalyst would be regenerated by heating at high temperature, no decrease was observed in catalytic activity after three cycles.

In situ growth of TS-1 on porous glass beads for ammoximation of cyclohexanone

In this work, porous glass beads supported with TS-1 particles have been successfully prepared through in situ crystallization. TS-1 particles with uniform size and high crystallization are well dispersed on the surface of porous glass beads. As the support, porous glass beads exhibit the advantages of more manageable surface chemistry, better chemical and thermal stability, and larger specific surface area compared to that of conventional TS-1 films on flat or tubular supports. The experimental results show that the surface chemistry has profound influence on the morphology of TS-1 particles. The catalytic performance of the material was characterized with the reaction of ammoximation of cyclohexanone. Complete conversion was reached after 20min in a stirred tank reactor with the selectivity of 100%. Compared with the commercial catalyst, the reaction rate was increased by 54 times. The prepared catalysts were packed in a bed reactor, and the effects of space time, content of catalyst, temperature and pressure were investigated. The conversion of 48.1% was reached by the catalyst with TS-1 loading of 0.183wt.% at 353K and the space time of only 1.57min, and 100% recovery in catalytic activity after 5 cycles was demonstrated.

Synthesis of Stainless-Steel-Net Supported TS-1 Catalyst and Its Catalytic Performance in Liquid-Phase Epoxidation Reactions

TS-1 particles were loaded on stainless-steel-net (SSN) to form an integrated material (TS-1/SSN) by secondary hydrothermal synthesis. This avoided completely the filtration separation in both catalyst preparation and catalytic applications in liquid-phase reactions. Seeding-assisted secondary crystallization prevented zeolite from detaching from the support during the synthesis process. The TS-1 particles were coated on the SSN support uniformly, and their loading amount was adjustable in the range of 7–25 wt % by repeating the seeding and crystallization processes. UV–visible and IR spectra verified that the titanium species in TS-1/SSN mostly occupied the tetrahedral coordination sites in the zeolite framework. TS-1/SSN was comparably active to conventional TS-1 particles in batchwise epoxidation of 1-hexene with H2O2. The zeolite particles maintained the catalytic activity and did not detach from the SSN after five reuses. Moreover, TS-1/SSN proved to be efficient and reusable in continuous epoxidation of allyl chloride where the separation of products and catalyst occurred easily.

Synthesis of TS-1 Molecular Sieves Using a New Ti Source

The incorporation of Ti in the MFI structure using a cheap and easy to handle source, the hexafluorotitanic acid, was successfully achieved without the formation of contaminant phases. The TS-1 samples with 1%, 2%, and 2.5% Ti present a linear increase in the cell parameters. This indicates that the Ti present in the solid is incorporated into the framework, and this is confirmed by infrared analysis. The TS-1 particles present morphology that is typical of the MFI structure. The UV-vis diffuse reflectance results indicate the existence of tetra- and hexacoordinated framework Ti species. Independent of Ti content, all of the samples present similar activity for the oxidation of cyclohexene using hydrogen peroxide as an oxidant agent. Also, a high selectivity for the formation of the corresponding epoxide is observed.

Adenovirus Protein VI Mediates Membrane Disruption following Capsid Disassembly

In contrast to enveloped viruses, the mechanisms involved in membrane penetration by nonenveloped viruses are not as well understood. In these studies, we determined the relationship between adenovirus (Ad) capsid disassembly and the development of membrane lytic activity. Exposure to low pH or heating induced conformational changes in wild-type Ad but not in temperature-sensitive Ad (ts1) particles that fail to escape the early endosome. Wild-type Ad but not ts1 particles permeabilized model membranes (liposomes) and facilitated the cytosolic delivery of a ribotoxin. Alterations in wild-type Ad capsids were associated with the exposure of a pH-independent membrane lytic factor. Unexpectedly, this factor was identified as protein VI, a 22-kDa cement protein located beneath the peripentonal hexons in the viral capsid. Recombinant protein VI and preprotein VI, but not a deletion mutant lacking an N-terminal amphipathic alpha-helix, possessed membrane lytic activity similar to partially disassembled virions. A new model of Ad entry is proposed based on our present observations of capsid disassembly and membrane penetration.

Synthesis of fibrous titanium silicalite (FTS-1) zeolite

Fibrous titanium silicalite (FTS-1) zeolite has been prepared from titanium silicalite (TS-1) particles that were less than 120 nm in diameter. The formation of FTS-1 was mainly affected by the particle size of the TS-1 zeolite. FTS-1 is formed by both capillary force and dehydroxylation among the TS-1 particles during the drying and evaporation process of the dispersed TS-1 particles in aqueous solution. The average length and the aspect ratio (length/diameter) of FTS-1 are 2.2 and mm 50~70, respectively. The obtained FTS-1 shows a two-dimensionally aligned surface that is affected by the treatment of dispersed TS-1 particles in aqueous solution. 29Si MAS n.m.r. spectra showed that the concentration of the hydroxyl group on the surface of TS-1 particles was decreased after the formation of FTS-1 and was reduced continuously up to 750 °C with calcination. This suggests that the condensation reaction of hydroxyl groups on the surface of TS-1 particles occurs by drying and heat treatment. After calcination at 750 °C, FTS-1 still exhibited characteristics of MFI-type structure with orthorhombic symmetry. It showed distinctive secondary pores due to the aggregation of TS-1 particles. This method of FTS-1 formation may suggest a new method for the preparation of various types of zeolites.

Preparation of Transparent TS-1 Zeolite Film by Using Nanosized TS-1 Particles

We report the first success in the preparation of transparent TS-1 zeolite film on a micro slide glass using nanosized TS-1 zeolite crystals (<100 nm). The nanosized TS-1 zeolite was crystallized at 80 °C and 1 atm. We intentionally controlled the zeolite particle size by using mild synthetic conditions and particle morphology from the sol state and formed micro- and macrocrack-free TS-1 zeolite film. Surface morphology and crystallinity of TS-1 zeolite were measured by using atomic force micrography and X-ray diffraction.