摘要:
Catalytic procedure in gas phase for the preparation of a symmetrical or asymmetrical organic carbonate having the general formula (I): ##STR1## wherein R and R', the same or different, represent a C.sub.1 -C.sub.4 alkyl radical, linear or branched, which includes reacting at least one alcohol having the general formula (II):R--OH or R'--OHwith carbon monoxide and oxygen in the presence of a catalyst composed of oxides, salts or complexes of cobalt.
摘要:
The invention relates to a new process which allows the preparation of TS-1 zeolites in a pure phase and with a crystallinity higher than 95%, operating at reduced reaction volumes, and obtaining high productivities and extremely high crystallization yields. The particular crystalline form of the TS-1 zeolite thus prepared, is also described.
摘要:
A process is described for the preparation of phenol by the hydrodeoxygenation of polyhydroxylated benzene derivatives or by the selective hydroxylation of benzene under depletive conditions, characterized in that the above-mentioned reactions are carried out in the presence of a catalyst based on multi component metal oxides comprising at least one metal selected from the groups VB, VIB, VIII, IB, IIB, IVA, VA.
摘要:
The invention relates to an enhanced process for the recycling of expanded polystyrene. Said process essentially comprises the reduction in volume of expanded polystyrene by means of dissolution in a solvent, separation of the insoluble components, selective precipitation of the polystyrene with an anti-solvent, separation, drying and extrusion of the precipitated polystyrene, recovery by distillation and recycling of the solvent. The process is characterized in that the anti-solvent is a butanol selected form n-butanol, iso-butanol or sec-butanol and the solvent is dimethyl carbonate, alone or in a mixture containing up to 25% by weight of butanol.
摘要:
Process for preparing alkylated aromatic compounds which comprises reacting an aromatic compound with a ketone and hydrogen in the presence of a catalytic composition comprising a solid acid material and copper. A preferred aspect is to use a catalytic composition also containing one or more elements selected from elements of groups IIIA, IVA, IIIB, IVB, VB, VIB, VIIB, group VIII limited to Fe, Ru and Os, and of the series of lanthanides. A particularly preferred aspect is to use a catalytic composition containing one or more elements selected from elements of groups IIIA and VIB.
摘要:
The invention relates to the use of a mixture, comprising one or more alkyl esters of fatty acids and one or more esters of fatty acids of glycerol carbonate, as a fuel or solvent.
摘要:
The present invention relates to a new zeolite having a beta-type crystalline structure, characterized by a distribution of the Lewis acid sites and Brønsted acid sites corresponding to a molar ratio [Lewis sites] [Brønsted sites] equal to or higher than 1.5. This new zeolite is useful in preparation processes of alkylated aromatic hydrocarbons through the alkylation and/or transalkylation of aromatic compounds. The preparation method of the new zeolite is also object of the present invention.
摘要:
The invention relates to a process for the production of linear alkanes, containing less than 6′ carbon atoms, from a mix comprising one or more hydrocarbons containing at least 6 carbon atoms. The process uses a catalytic composition comprising particular combinations of a Y-type zeolite, at least one element selected from Zn, Mo, Cu, Ga, In, W, Ta, Zr, Ti, metals of Group VIII and optionally one or more lanthanides.
摘要:
Unexpected corrosion of downstream sections of a dialkyl carbonate manufacturing apparatus has been traced to alkyl chloroformate impurities, which slowly decompose to yield hydrochloric acid. An improved process and apparatus for dialkyl carbonate synthesis reduce corrosion by physically removing or chemically decomposing the alkyl chloroformate impurities within the corrosion-resistant upstream sections of the apparatus. The alkyl chloroformate may be decomposed by passing it through a passageway at a temperature of about 30 C to about 130° C. for a time of about 0.5 hour to about 10 hours. The passageway may include one or more holding vessels or a tubular section that promotes plug flow.
摘要:
A description follows of vulcanizable compositions of nitrile rubbers containing a plasticizer, a vulcanizing agent and normal additives, wherein the plasticizer is an organic carbonate selected from those which can be defined with the formula (I): ##STR1## or with the formula (II): ##STR2## wherein R, R.sup.1, R.sup.2, X and n are as defined in the description.