F+:Highly flammable;
74-85-1Relevant articles and documents
Stable and selective electrochemical reduction of carbon dioxide to ethylene on copper mesocrystals
Chen, Chung Shou,Handoko, Albertus D.,Wan, Jane Hui,Ma, Liang,Ren, Dan,Yeo, Boon Siang
, p. 161 - 168 (2015)
Stable and selective electrochemical reduction of carbon dioxide to ethylene was achieved using copper mesocrystal catalysts in 0.1 M KHCO3. The Cu mesocrystal catalysts were facilely derived by the in situ reduction of a thin CuCl film during the first 200 seconds of the CO2 electroreduction process. At -0.99 V vs. RHE, the Faradaic efficiency of ethylene formation using these Cu mesocrystals was ～18× larger than that of methane and forms up to 81% of the total carbonaceous products. Control CO2 reduction experiments show that this selectivity towards C2H4 formation could not be replicated by using regular copper nanoparticles formed by pulse electrodeposition. High resolution transmission electron microscopy reveals the presence of both (100)Cu facets and atomic steps in the Cu mesocrystals which we assign as active sites in catalyzing the reduction of CO2 to C2H4. CO adsorption measurements suggest that the remarkable C2H4 selectivity could be attributed to the greater propensity of CO adsorption on Cu mesocrystals than on other types of Cu surfaces. The Cu mesocrystals remained active and selective towards C2H4 formation for longer than six hours. This is an important and industrially relevant feature missing from many reported Cu-based CO2 reduction catalysts.
Beadle et al.
, p. 265,266-269 (1972)
Ring Size and Strain as a Control of Reaction Selectivity: Ethylene Sulfide on Mo(110)
Roberts, Jeffrey T.,Friend, C. M.
, p. 7899 - 7900 (1987)
-
Reaction of the ethyl radical with oxygen at millitorr pressures at 243-368 K and a study of the Cl + HO2, ethyl + HO2, and HO2 + HO2 reactions
Dobis, Otto,Benson, Sidney W.
, p. 8798 - 8809 (1993)
Ethyl radicals formed in the reaction of C2H6 + Cl are allowed to react with molecular oxygen in a very low pressure reactor (VLPR) experimental flow system over the temperature range of 243-368 K. Mass spectrometric analysis of reactants and products made possible the determination of rate constants (cm3/(molecule·-s)) of all major reaction steps. Mass balances for C, H, and Cl are good to ±4% on average. The elementary steps are the following: C2H5 + O2 → HO2 + C2H4, k6 = (1.42 ± 0.38) × 10-17 exp[(5064 ± 154)/RT], measured independently from recording C2H5 consumption or C2H4 formation rates; 2HO2 → H2O2, k7 = (4.50 ± 0.56) × 10-13 exp[(1064 ± 77)/RT]; C2H5 + HO2 → H2O2 + C2H4, k8a = (2.98 ± 0.11) × 10-12; Cl + HO2 → HCl + O2, k9 = (4.45 ± 0.06) × 10-11. Activation energies are given in cal/mol. Reactions 8a and 9 show no change in the temperature range of measurements, while reactions 6 and 7 both have negative temperature dependence. The radical oxidation reaction 6 is suggested to occur via excited ethylperoxy and 2-hydroperoxyethyl radical formations as consecutive reversible steps.
Rice,Herzfeld
, p. 284 (1934)
Cross-metathesis vs. silylative coupling of vinyl alkyl ethers with vinylsilanes catalyzed by a ruthenium-carbene complex (Grubbs catalyst)
Marciniec,Kujawa,Pietraszuk
, p. 671 - 675 (2000)
Grubbs complex, (PCy3)2Cl2Ru=CHPh (I) is a very effective catalyst of the cross-disproportionation of vinyl-trisubstituted silanes H2C=CHSiR3 [where R3 = Me3, PhMe2, (OEt)3] with vinyl alkyl ethers H2C=CHOR' [where R' = ethyl, propyl, butyl, t-butyl, t-pentyl, 2-(ethyl)hexyl, cyclohexyl, trimethylsilyl] to yield a mixture of (E + Z) 1-silyl-2-alkoxyethenes. The reaction occurs quantitatively under milder conditions (60 °C) than the analogous one catalyzed by Ru-H and/or Ru-Si complexes reported previously (80 °C). The stoichiometric reaction of (I) and (PCy3)2Cl2Ru=CH2 (III) with vinyl ethyl ether leads to the formation of (PCy3)2Cl2Ru=CH(OEt) (II), inactive in the stoichiometric reaction with vinylsilanes but very active in the catalytic process. Experiments with the use of deuterated vinylsilanes indicate the non-metallacarbene mechanism of the reaction and provide evidence for the initiation of Ru-H bond formation via the hydrovinylation with vinylsilanes.
Porter
, p. 827 (1957)
Calorimetric Study of Vanadium Pentoxide Catalysts Used in the Reaction of Ethane Oxidative Dehydrogenation
Le Bars, J.,Vedrine, J. C.,Auroux, A.,Pommier, B.,Pajonk, G. M.
, p. 2217 - 2221 (1992)
Vanadium pentoxide catalysts have been studied in the partial oxidation reaction of ethane in the 723-843 K temperature range.The relationship between the acid-base properties and the catalytic behavior was investigated.The number and character of acidic sites of V2O5 catalysts were determined by studying the adsorption of a basic molecule using microcalorimetry.The reducibility level and the evolution of the surface state, as well as the heat evolved, were studied by using a pulse method with pure ethane only.The reaction of ethane oxidative dehydrogenation was studied by a continuous flow method and the activation energies for the formation of C2H4 and CO were calculated.The selectivity of the catalyst was interpreted in connection with the acid-base properties.The strong sites were observed to decrease rapidly with time on stream, although the catalysts were still active.Temperature-programmed reduction of V2O5 using a TG-DSC coupling was also investigated with hydrogen, ethylene, or ethane as reducers.The different heats of reduction are given.It was observed that C2H4 is a much more efficient reducing agent than H2 and C2H6.Following each reduction, reoxidation studies by oxygen were performed in the same equipment showing clearly different steps in the reoxidation process.
Rate Constant and Product Branching for the Vinyl Radical Self Reaction at T = 298 K
Thorn, R. P.,Payne, W. A.,Stief, L. J.,Tardy, D. C.
, p. 13594 - 13602 (1996)
The rate constant and product branching for the self reaction of C2H3 has been measured using the discharge-flow kinetic technique coupled to mass spectrometric detection at T = 298 K and 1 Torr nominal pressure (He).C2H3 is produced by the reaction of F with C2H4, which also forms C2H3F + H.In addition to the C2H3 self reaction, C2H3 also decays by reaction with H and by wall loss processes.The result obtained by parameter fitting the C2H3 decay curves was k(C2H3 + C2H3) = (1.41 +/- 0.60)E-10 cm3 molecule-1 s-1, where k is defined by d/dt = 2k2.Results from the product studies showed that the recombination product 1,3-butadiene was not observed at 1 Torr and that the ratio product formed/0 was 0.65 +/- 0.14 for the combined C2H3 + C2H3 and C2H3 + H reactions.Both observations are consistent with C2H2 + C2H4 being the exclusive C2H3 + C2H3 products, since the maximum yield of C2H2 from the combined C2H3 + C2H3 and C2H3 + H reactions is 0.59.The experimental observations that k1 is independent of pressure and that no 1,3-butadiene (product of C2H3 combination) is observed at 1 Torr pressure requires a mechanism in which the chemically activated 1,3-butadiene undergoes a unimolecular reaction.It is postulated that the 1,3-butadiene first isomerizes to cyclobutene, which then unimolecularly decomposes to C2H2 and C2H4.Although the former reaction is well documented, the latter reaction has not been previously reported.RRKM calculations predict a pressure dependence similar to what is experimentally observed.
Boron-doped CuO nanobundles for electroreduction of carbon dioxide to ethylene
Wan, Qiang,Zhang, Jianling,Zhang, Bingxing,Tan, Dongxing,Yao, Lei,Zheng, Lirong,Zhang, Fanyu,Liu, Lifei,Cheng, Xiuyan,Han, Buxing
, p. 2750 - 2754 (2020)
Novel boron-doped CuO nanobundles are designed for CO2 reduction to the single multi-carbon product of ethylene, and their faradaic efficiency can reach 58.4% with a current density of 18.2 mA cm-2. This active, selective and simply prepared electrocatalyst provides a promising electrocatalyst candidate for CO2 reduction to ethylene.
Ag-Ni bimetallic SiBEA zeolite as an efficient catalyst of hydrodechlorination of 1,2-dichloroethane towards ethylene
?r?bowata,Zielińska,Baran,S?owik,Dzwigaj
, p. 154 - 160 (2015)
Dealuminated form of BEA zeolite with Si/Al ratio of 1500 was used for the synthesis of Ag2.0SiBEA, Ni2.0SiBEA and Ag2.0Ni2.0SiBEA by two-step postsynthesis method. The calcination of zeolite samples led to the formation of well dispersed isolated mononuclear Ag(I) and Agnδ + clusters and a pseudo-tetrahedral Ni(II), incorporated in BEA framework as evidenced by DR UV-vis investigations. The treatment of samples in flowing 10% H2/Ar stream gave small (average 3.1 nm) and well dispersed metal nanoparticles. Reduced catalysts were investigated in 1,2-dichloroethane hydrodechlorination at atmospheric pressure, at low reaction temperature (523 K) with ～ 100% of selectivity to ethylene, desired product of the reaction.
Methyl vinyl glycolate as a diverse platform molecule
S?lvh?j, Amanda,Taarning, Esben,Madsen, Robert
, p. 5448 - 5455 (2016)
Methyl vinyl glycolate (methyl 2-hydroxybut-3-enoate, MVG) is available by zeolite catalyzed degradation of mono- and disaccharides and has the potential to become a renewable platform molecule for commercially relevant catalytic transformations. This is further illustrated here by the development of four reactions to afford industrially promising structures. Catalytic homo metathesis of MVG using Grubbs-type catalysts affords the crystalline dimer dimethyl (E)-2,5-dihydroxyhex-3-enedioate in excellent yield and with meso stereochemical configuration. Cross metathesis reactions between MVG and various long-chain terminal olefins give unsaturated α-hydroxy fatty acid methyl esters in good yields. [3,3]-Sigmatropic rearrangements of MVG also proceed in good yields to give unsaturated adipic acid derivatives. Finally, rearrangement of the allylic acetate of MVG proceeds in acceptable yield to afford methyl 4-acetoxycrotonate.
From vanadia nanoclusters to ultrathin films on TiO2(110): Evolution of the yield and selectivity in the ethanol oxidation reaction
Artiglia, Luca,Agnoli, Stefano,Savio, Letizia,Pal, Jagriti,Celasco, Edvige,Rocca, Mario,Bondino, Federica,Magnano, Elena,Castellarin-Cudia, Carla,Netzer, Falko P.,Granozzi, Gaetano
, p. 3715 - 3723 (2014)
Oxide-on-oxide systems are becoming increasingly important in nanocatalysis and surface engineering, because of the creation of hybridized interfaces holding high reactivity and selectivity toward oxidation reactions. Here we report on the results of a multitechnique surface science study conducted on an oxide/oxide model system. By depositing increasing amounts of vanadium oxide (VOx) on a titanium dioxide-rutile(110) substrate, we were able to follow the morphology and oxidation state of the overlayer. Three growth modes were detected: nanoclusters at low coverage (0.3 and 0.5 monolayer), one-dimensional strands aligned along the substrate [001] direction at monolayer coverage, and three-dimensional nanoislands at higher coverage (2.0 and 5.0 monolayers). All these structures share the same oxidation state (V2O3). We studied the reactivity and selectivity of these model catalysts toward partial oxidation of ethanol, finding that both of them depend on the VOx thickness. Nanoclusters can yield acetaldehyde through low-temperature oxidative dehydrogenation but show a scarce selectivity in the investigated temperature range. The monolayer coverage is the most reactive toward ethanol dehydration to ethylene, showing also good selectivity. Similar results are found at high coverage, although the overall reactivity of the systems toward alcohol oxidation decreases.
Ring opening reaction dynamics in the reaction of hydrogen atoms with ethylene oxide
Shin, S. K.,Jarek, R. L.,Boehmer, E.,Wittig, C.
, p. 6615 - 6624 (1994)
Ethylene oxide, C2H4O, is a three-membered ring with a single oxygen atom bridging the two carbons.Reactions of H and D atoms with ethylene oxide have been studied in the gas phase to provide insight into the dynamics of three-membered ring opening.H atoms were produced by photolyzing HI in the wavelength range 240-266 nm.The channel leading to OH+C2H4 was monitored via laser-induced fluorescence (LIF) of the OH A 2Σ 2Π system.The D atom reaction yields OD with no hydrogen scrambling.With an available energy of 23 000 cm-1, the average OH D rotational energy is ca. 350 cm-1 for OH(ν=0) and OD(ν=0) and ca. 250 cm-1 for OD(ν=1).OH(ν=1) was not observed, while the OD(ν=1) population was about one-tenth that of OD(ν=0).There was no apparent bias in populations between Λ doublets in each of the spin-orbit states for both OH and OD.Doppler broadening of OH(ν=0) rotational lines was measured to evaluate the average center-of-mass (c.m.) translational energy, which was found to be ca. 2300 cm-1.On average, the ring opening process deposits ca. 10percent of the available energy into c.m. translation, ca. 2percent into OH rotation, and ca. 88percent into ethylene internal energy.Comparison with CH2CH2OH unimolecular dissociation dynamics and theoretical transition state calculations leads to a likely mechanism in which hydrogen abstracts oxygen via sequential C-O bond fission without involving a long-lived CH2CH2OH intermediate.
METATHESIS OF VINYLTRIALKOXYSILANES
Marciniec, Bogdan,Gulinski, Jacek
, p. C19 - C21 (1984)
Ruthenium(II) and ruthenium(III) complexes have been found to be the first efficient catalysts for the metathesis of organosilicon olefins. trans-1,2-Bis(triethoxysilyl)ethene is prepared via metathesis of vinyltriethoxysilane catalyzed by ruthenium complexes with a yield above 80percent.
Kinetic and process study of ethanol steam reforming over Ni/Mg(Al)O catalysts: The initial steps
Zeng, Guangming,Li, Yongdan,Olsbye, Unni
, p. 312 - 322 (2016)
In this work, a 2 wt.% Ni/Mg(Al)O catalyst was subjected to kinetic studies for the ethanol steam reforming (ESR) reaction at 500 °C, with space-time ranging from 0.03 to 0.50 mg min/ml and with PC2H5OH:PH2O:PInert = 0.0163:0.0500:0.93 (atm) as standard conditions. The results indicate that dehydrogenation and dehydration of ethanol were the predominant reactions. CH3CHO and C2H4 were primary products and formed in parallel on different active sites. H2O and C2H5OH competed for the same active sites on the catalyst surface and the reaction order with respect to H2O was negative. The apparent activation energy for ethanol conversion was 110 kJ/mol. Furthermore, temperature-programmed desorption experiments confirmed the competing adsorption of C2H5OH and H2O. Temperature-programmed deuteration of used catalyst showed that the catalyst contained C2H4, CHx, acetate and carbonate species during ESR reaction.
Control of Surface Barriers in Mass Transfer to Modulate Methanol-to-Olefins Reaction over SAPO-34 Zeolites
Gao, Mingbin,Li, Hua,Liu, Zhongmin,Peng, Shichao,Yang, Miao,Ye, Mao
, p. 21945 - 21948 (2020)
Mass transfer of guest molecules has a significant impact on the applications of nanoporous crystalline materials and particularly shape-selective catalysis over zeolites. Control of mass transfer to alter reaction over zeolites, however, remains an open challenge. Recent studies show that, in addition to intracrystalline diffusion, surface barriers represent another transport mechanism that may dominate the overall mass transport rate in zeolites. We demonstrate that the methanol-to-olefins (MTO) reaction can be modulated by regulating surface permeability in SAPO-34 zeolites with improved chemical liquid deposition and acid etching. Our results explicitly show that the reduction of surface barriers can prolong catalyst lifetime and promote light olefins selectivity, which opens a potential avenue for improving reaction performance by controlling the mass transport of guest molecules in zeolite catalysis.
The Gas-phase Amino-Claisen Rearrangement of Protonated N-Allylaniline
Kingston, Eric E.,Beynon, John H.,Vandezonneville, Alexandra,Flammang, Robert,Maquestiau, Andre
, p. 437 - 442 (1988)
Metastable molecular protonated ions of N-allylaniline dissociate with significant losses of ethene and ammonia in the flight path of a mass spectrometer.The structures of the daughter ions formed on the loss of ethene have been elucidated using collision-induced dissociation and it is postulated that two isomeric structures are formed, one corresponding to molecular protonated ions which have undergone an amino-Claisen rearrangement.The relative proportion of this rearranged species is dependent on the exothermicity of the proton-transfer reaction between the sample molecule and the chemical ionization reagent gas ion.It is proposed that the two isomeric parent species differ in the site of protonation.
Ammoxidation of Ethane to Acetonitrile over Metal-Zeolite Catalysts
Li, Yuejin,Armor, John N.
, p. 511 - 518 (1998)
Ammoxidation of ethane to acetonitrile was studied over a variety of metal ion exchanged zeolite catalysts. We discovered that ethane can be efficiently converted to acetonitrile over some Cozeolite catalysts. The type of zeolite is very important. In this regard, ZSM-5, beta, and NU-87 are superior to others. Among various transition metal cations, Co2+ is most active for acetonitrile formation. Kinetic studies on Co-ZSM-5 show that the nitrile formation rate is first order in NH3, 0.5 order in C2H6, and 0.8 order in O2. In the absence of O2, no reaction occurs. A reaction scheme is proposed, whereby C2H4, a reactive intermediate, is thought to add to a strongly adsorbed NH3 forming an adsorbed ethylamine, which is subsequently dehydrogenated to form C2H3N.
A Laser Flash Photolysis, Time-Resolved Fourier Transform Infrared Emission Study of the Reaction Cl + C2H5 -> HCl(υ) + C2H4
Seakins, Paul W.,Woodbridge, Eric L.,Leone, Stephen R.
, p. 5633 - 5642 (1993)
The atom-radical reaction Cl + C2H5 -> HCl(υ) + C2H4 is studied using laser flash photolysis, time-resolved Fourier transform infrared emission spectroscopy and broad band infrared chemiluminescence.The Cl atoms and ethyl radicals are produced from a number of different precursors using one or two lasers.The initial HCl vibrational distribution is determined to be HCl (υ=1/2/3/4=0.39+/-0.04/0.29+/-0.03/0.22+/-0.02/0.10+/-0.02).The vibrational distribution is characteristic of an addition-elimination mechanism and can be reproduced using modified statistical theories of energy partitioning within the (excit.) intermediate.The time evolution of the HCl(υ=4) emission is used to estimate a rate coefficient for this reaction of (3.0+/-1.0)*10-10 cm3 molecule-1 s-1.
Reaction of Dichloroethane and Oxygen on a Rough Silver Surface
Gu, X. J.,Akers, K. L.,Moskovits, M.
, p. 3696 - 3700 (1991)
Electron energy loss spectroscopy (EELS) results indicate that dichloroethane physisorbs at 55 K on rough, coldly deposited silver.By contrast surface-enhanced Raman scattering (SERS) spectroscpoy reveals that a large fraction of the adsorbed dichloroethane decomposes into ethylene and chlorine on the same type of surface at 55 K and above.With postadsorption of oxygen, dichloroethane or its decomposition products oxidize at temperatures equal to or greater than 140 K, forming products that include a species with a carbonyl group that is either bonded directly to chlorine, as in phosgene or oxalyl chloride, or to a metal atom with chlorine nearby.No hydrogen is bonded sufficiently closely to the CO group in the species to cause a deuterium shift.A second oxidation product is also detected containing an OH group.These reactions occur exclusively at the SERS-active sites and are undetected by EELS.We therefore conclude that SERS and EELS probe different surface sites.EELS seems to be the more globally sensitive technique, and SERS appears to be sensitive to fewer but chemically more reactive sites.This may be due either to the fact that these chemically reactive sites are located at "interior" portions of the surface, i.e., in valleys and pits located among surface features where, it has been suggested, the electromagnetic enhancement is unusually large, or to the extra enhancement that sometimes accompanies chemisorption resulting from the increase of the Raman polarizability of the surface complex, or perhaps to both effects.Whatever the reason, it appears that SERS is uniquely sensitive to those sites where the most interesting chemistry occurs on silver.These may also be the catalytically most important sites.
Observation of ethylsilylene product in the infrared multiphoton dissociation of ethylsilane
Francisco, J. S.,Villanueva, J. L.,Reck, G.
, p. 820 - 821 (1991)
-
Hine,Brader
, p. 3964 (1953)
PHOTOINDUCED DECOMPOSITION OF FUSARIC ACID WITH THE LOSS OF ETHYLENE
Klochkov, S. G.,Dubrovskaya, E. S.,Vasin, Yu. A.
, p. 1097 (1992)
-
Infrared-induced reaction on MoO3 using a tunable infrared free electron laser
Moula, Golam,Sato, Shinsuke,Irokawa, Katsumi,Niimi, Hironobu,Suzuki, Shushi,Asakura, Kiyotaka,Kuroda, Haruo
, p. 836 - 842 (2008)
We observed the IR-induced reaction of C2H5OH on MoO3 using a pulsed and tunable infrared free electron laser (IR-FEL). The IR-FEL-induced reaction showed wavelength dependency and requires light stronger than a certain threshold level. The C2H5OH was converted mainly to C2H4 only when the MoO3 was irradiated with focused IR-FEL at 967 and 814 cm-1 corresponding to Mo=O stretching modes, whereas IR light at 1200 cm-1 induced no reaction. The origin of this IR-FEL-induced reaction is discussed.
C?C Coupling Is Unlikely to Be the Rate-Determining Step in the Formation of C2+ Products in the Copper-Catalyzed Electrochemical Reduction of CO
Chang, Xiaoxia,Li, Jing,Lu, Qi,Xiao, Hai,Xiong, Haocheng,Xu, Bingjun,Xu, Yifei,Zhang, Haochen
supporting information, (2021/12/03)
The identity of the rate-determining step (RDS) in the electrochemical CO reduction reaction (CORR) on Cu catalysts remains unresolved because: 1) the presence of mass transport limitation of CO; and 2) the absence of quantitative correlation between CO partial pressure (pCO) and surface CO coverage. In this work, we determined CO adsorption isotherms on Cu in a broad pH range of 7.2–12.9. Together with electrokinetic data, we demonstrate that the reaction orders of adsorbed CO at pCO 0.6 atm are 1st and 0th, respectively, for multi-carbon (C2+) products on three Cu catalysts. These results indicate that the C?C coupling is unlikely to be the RDS in the formation of C2+ products in the CORR. We propose that the hydrogenation of CO with adsorbed water is the RDS, and the site competition between CO and water leads to the observed transition of the CO reaction order.
Efficient Polyester Hydrogenolytic Deconstruction via Tandem Catalysis
Kratish, Yosi,Marks, Tobin J.
supporting information, (2021/12/22)
Using a mechanism-based solvent-free tandem catalytic approach, commodity polyester plastics such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN) are rapidly and selectively deconstructed by combining the two air- and moisture-stable catalysts, Hf(OTf)4 and Pd/C, under 1 atm H2, affording terephthalic acid (or naphthalene dicarboxylic acid for PEN) and ethane (or butane for PBT) in essentially quantitative yield. This process is effective for both laboratory grade and waste plastics, and comingled polypropylene remains unchanged. Combined experimental and DFT mechanistic analyses indicate that Hf(OTf)4 catalyzes a mildly exergonic retro-hydroalkoxylation reaction in which an alkoxy C?O bond is first cleaved, yielding a carboxylic acid and alkene, and this process is closely coupled to an exergonic olefin hydrogenation step, driving the overall reaction forward.
Impact of composition and structural parameters on the catalytic activity of MFI type titanosilicalites
Bruk, Lev,Chernyshev, Vladimir,Khramov, Evgeny,Kravchenko, Galina,Kustov, Aleksander,Kustov, Leonid,Kuz'Micheva, Galina,Markova, Ekaterina,Pastukhova, Zhanna,Pirutko, Larisa
, p. 3439 - 3451 (2022/03/14)
Titanosilicalite of the MFI type was obtained via a hydrothermal method. Its initial and annealed at 75 °C (TS-1P(75)) and 500 °C (TS-1P(500)) forms were studied by X-ray powder diffraction (PXRD), X-ray absorption spectroscopy (XAS-method), Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), temperature-programmed ammonia desorption (TPD NH3), and pyridine adsorption (Py). The full-profile Rietveld method allowed us to observe the presence of the organic template tetrapropylammonium hydroxide (TPAOH) in the framework voids, as well as to determine the silicate module (Si/Ti = 73.5) and the distribution of Ti4+ ions over the MFI-type structure sites (Ti atoms replace Si ones in two positions: T1 and T6). The coordination numbers of titanium (CNTi = 4.6 for TS-1P and TS-1P(75), CNTi = 3.8 for TS-1P(500)) were established by the XAS-method. The catalytic activity of titanosilicalites was found in the reactions of nitrous oxide decomposition (the maximal decomposition rate is demonstrated for the TS-1P(75) sample), allyl chloride epoxidation to epichlorohydrin (the best combination of all indicators was exhibited for the TS-1P sample) and propane conversion (maximum propane conversion, and butadiene and propylene selectivity were observed in both TS-1P(75) and TS-1P(500) samples). Mechanisms for the catalytic processes are proposed. The relationship between the catalytic properties and the composition (Si/Ti), Ti4+ ion distribution over the MFI-type structure sites, the local environment of titanium ions, and the number of acid sites in the titanosilicalites are discussed.
