Extraction catalyst from aqueous

InTox A process for destroying toxic wastes in aqueous solution by oxidation with oxygen at high temperatures and pressures in a pipe reactor. No catalyst is required. The reactions take place at approximately 300°C and 120 atm. Developed by InTox Corporation, UK, based on a process for extracting aluminum from bauxite developed by Lurgi in the 1960s. See also Zimpro. 

Merox [Mercaptan oxidation] A process for removing mercaptans from petroleum fractions by extracting them into aqueous sodium hydroxide and then catalytically oxidizing them to disulfides using air. The catalyst is an organometallic compound, either a vanadium phthalocyanine supported on charcoal, or a sulfonated cobalt phthalocyanine. Developed by UOP in 1958 and widely licensed by 1994, more than 1,500 units had been built, worldwide. Unzelman, G. H. and Wolf, C. J., in Petroleum Processing Handbook, Bland, W. F. and Davidson, R. L., Eds., McGraw-Hill, New York, 1967, 3-128. 

It is possible to extract the nanocolloids from aqueous solution into an organic phase or to support them onto inorganic supports by what is called the precursor method (described in Section 3.5) to generate heterogeneous catalysts. Such catalysts find application in chemical catalysis, e.g., in selective hydrogenation of fatty acids. 

Other patents illustrate the use of a solvent extraction process to separate the alcohol products from the catalyst (130, 131). When a catalyst solution containing alcohol products is mixed with water and a water-immiscible solvent, the alcohol products are extracted into the aqueous phase and the rhodium species enter the water-immiscible solvent. The effectiveness of the extraction and the stability of the rhodium catalyst can be greatly increased by carrying out the process under CO pressure (131). 

In the classical oxo process the catalyst cohalt carbonyl is formed in situ by introducing divalent cobalt into the reactor. High temperature is required for this catalyst formation that gives a mixture of aldehydes and alcohols containing only 60-70% of linear product. A new BASF process using cobalt carbonyl hydride shows improved selectivity and efficient catalyst recovery. The catalyst is prepared by passing an aqueous solution of cobalt salt over a promoter and extracting the catalyst from the water phase with olefin. 

Step 2 Extraction of the Catalyst from the Aqueous Solution. It is not feasible technically to charge the aqueous solution of cobalt carbonyl hydride directly into the hydroformylation reactor because two phases may form, especially with the long chain olefins. The most direct and most efficient way to eliminate water while permitting full use of the carbonyl catalyst is to extract it from the water phase with the olefin intended for hydroformylation. The extraction is carried out between... 

The extraction may be carried out in a countercurrent or concurrent extraction column. If there is sufficient mixing of the two phases, a very short contact time even for long chain olefins is adequate to ensure complete transfer of the catalyst from the aqueous phase into the olefin. 

Most reactions in two-phase systems occur in a liquid phase following the transfer of a reactant across an interface these are commonly known as extractive reactions. If the transfer is facilitated by a catalyst, it is known as phase-transfer catalysis [2]. Unusually, reactions may actually occur at an interface (interfacial reactions) examples include solvolysis and nucleophilic substitution reactions of aliphatic acid chlorides [3 ] and the extraction of cupric ion from aqueous solution using oxime ligands insoluble in water [4], see Section 5.2.1.3(ii). 

This conversion, similar to that of butenes to butadiene (see Section 6.1.1.1), is carried out by Shell in the presence of steam, on an Fe203/Cr203/K2C03 catalyst, at about 600"C The effluent is cooled by oil which absorbs the polymers formed The gas is then compressed before separation, which comprises extractive distillation with aqueous aceto> nitrile, followed by rectification of the isoprene. Shell daims the ability to treat butenes and isoamylenes simultaneously to produce butadiene and isoprene. Some idea of the composition of the effluents from sulfuric add extraction and dehydrogenation is given by Table 6.6. 

Liquid extraction is utilized by a wide variety of industries. Applications include the recovery of aromatics, decaffeination of coffee, recovery of homogeneous catalysts, manufacture of penicillin, recovery of uranium and plutonium, lubricating oil extraction, phenol removal from aqueous wastewater, and extraction of acids from aqueous streams. New applications or refinements of solvent extraction processes continue to be developed. 

Universal Oil Products supplies a solid form of PPA on kieselguhr ( No. 2 Polymerization catalyst ). In a study of the action of PPA on cis rans,trans-, 9-cyclododecatriene, Wellman et al. found the UOP solid catalyst more convenient than the sirup. The solid catalyst can be removed by filtration, and extraction of the product from aqueous PPA is avoided. The reaction alfords a mixture containing acenaphthene and decahydroacenaphthene. 

Well ordered mesoporous silicate films were prepared in supercritical carbon dioxide.[218] In the synthesis in aqueous or alcoholic solution, film morphology of preorganized surfactants on substrate cannot be fully prescribed before silica-framework formation, because structure evolution is coincident with precursor condensation. The rapid and efficient preparation of mesostructured metal oxides by the in situ condensation of metal oxides within preformed nonionic surfactants can be done in supercritical CCU- The synthesis procedure is as follows. A copolymer template is prepared by spin-coating from a solution containing a suitable acid catalyst. Upon drying and annealing to induce microphase separation and enhance order, the acid partitions into the hydrophilic domain of the template. The template is then exposed to a solution of metal alkoxide in humidified supercritical C02. The precursor diffuses into the template and condenses selectively within the acidic hydrophilic domain of the copolymer to form the incipient metal oxide network. The templates did not go into the C02 phase because their solubility is very low. The alcohol by-product of alkoxide condensation is extracted rapidly from the film into the C02 phase, which promotes rapid and extensive network condensation. Because the template and the metal oxide network form in discrete steps, it is possible to pattern the template via lithography or to orient the copolymer domains before the formation of the metal oxide network. 

Hydrogenation reaction a reaction in which hydrogen is added, with a catalyst present, to a carbon-carbon multiple bond. (22.2) Hydrohaiic acid an aqueous solution of a hydrogen halide. (20.7) Hydrometaiiui y a process for extracting metals from ores by use of aqueous chemical solutions. Two steps are involved selective leaching and selective precipitation. (21.8)... 

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