Titanium compounds catalysts

The dichloro bis(binaphthyl-Cp) titanium compound (catalyst 1 in Scheme 757) has shown excellent ability to catalyze the asymmetric epoxidation of unfuctionalized alkenes with virtually the same selectivity as previously... 

HDPE resias are produced ia industry with several classes of catalysts, ie, catalysts based on chromium oxides (Phillips), catalysts utilising organochromium compounds, catalysts based on titanium or vanadium compounds (Ziegler), and metallocene catalysts (33—35). A large number of additional catalysts have been developed by utilising transition metals such as scandium, cobalt, nickel, niobium, molybdenum, tungsten, palladium, rhodium, mthenium, lanthanides, and actinides (33—35) none of these, however, are commercially significant. 

Organic Titanium Compounds as A.crylicT.sterA.lcoholjsis Catalysts Titanium Intermediates, Ltd., London, 1967. 

The first production of syndiotactic polystyrene has been credited to research workers at Idemitsu Kosan in 1985 who used cyc/opentadienyl titanium compounds with methyl aluminoxane as catalyst. 

Polybibenzoates are a kind of thermotropic polyesters obtained by polycondensation of 4,4 -biphenyldicar-boxylic acid (p,p -bibenzoic acid) with a diol. These polyesters contain the biphenyl group, which is one of the simplest mesogens. They are synthesized by melt transesterification of the dimethyl or diethyl ester of p,p -bibenzoic acid and the corresponding diol, using a titanium compound as catalyst, according to the following scheme ... 

Ziegler-Natta catalysts-—there are many different formulations—are organometallic transition-metal complexes prepared by treatment of an alkyl-aluminum with a titanium compound. Triethylaluminum and titanium tetrachloride form a typical preparation. 

Tetralin, hydrogenation of, 12 Titanium compounds as catalysts, 188 Titanium dichloride, 192, 193 number of propagation centers, 198-200 Titanium trichloride, 193, 194 Toluene in exhaust gases, 67 Transalkylation, 141, 142 Transalkylidenation, 142 Transition metal compounds as catalysts, 174... 

Quaternary oxalkylated polycondensates can be prepared by esterification of an oxalkylated primary fatty amine with a dicarbonic acid. An organometallic titanium compound is used as a catalyst for condensation [842]. The reaction product is then oxalkylated in the presence of a carbon acid [841], These polycondensates can be used as demulsifiers for crude oil emulsions and as corrosion inhibitors in installations for the production of natural gas and crude oil they can and also be used in processing. 

Epoxidation catalysts, organic titanium compounds as, 25 135 Epoxide determinations, 10 385 Epoxide equivalent mass (EEM), 10 355 Epoxide equivalent weight (EEW), 10 355, 361-363, 385... 

Organic titanium compounds, 25 71-158 See also Titanium compounds in adhesives, 25 122 alkoxides, 25 72-86 as catalysts, 25 122 as coupling agents for polymer composites, 25 129-130... 

Photolytic. An aqueous solution containing p-chloronitrobenzene and a titanium dioxide (catalyst) suspension was irradiated with UV light ilk >290 nm). 2-Chloro-5-nitrophenol was the only compound identified as a minor degradation product. Continued irradiation caused additional degradation yielding carbon dioxide, water, hydrochloric and nitric acids (Hustert et al., 1987). 

Jacoby et al. (1994) studied the photocatalytic reaction of gaseous trichloroethylene in air in contact with UV-irradiated titanium dioxide catalyst. The UV radiation was kept less than the maximum wavelength so that the catalyst could be excited by photons, i.e., X <356 nm. Two reaction pathways were proposed. The first pathway includes the formation of the intermediate dichloroacetyl chloride. This compound has a very short residence time and is quickly converted to the following compounds phosgene, carbon dioxide, carbon monoxide, carbon dioxide, and hydrogen chloride. The second pathway involves the formation of the final products without the formation of the intermediate. 

Titanium tetrachloride is used to prepare titanium dioxide and most other titanium compounds. It also is used in making iridescent glass arificial pearls and smoke screens. The compound is a polymerization catalyst. 

The activity of titanium based catalysts for the oxidation of organic compounds is well known. Wulff et al. in 1971 [1] patented for Shell Oil a process for the selective epoxidation of propylene with hydroperoxides like ethylbenzene hydroperoxide (EBH) or tertiary-butyl hydroperoxide (TBH) with the use of a catalyst made of Ti02 deposited on high surface area Si02. A Shell Oil plant for the production of 130,000 tons/y of propylene oxide at Moerdijk, Holland, is based on this technology. 

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