摘要:
A catalyst for the treatment of exhaust gases from an internal combustion engine comprises a support including a porous layer which latter includes at least one inorganic refractory oxide and an active phase containing at least cerium, iron and platinum, characterized in that said porous layer comprises at least the following percentages by weight0.3% to 4.4% of cerium;0.1% to 3.5% of iron; and0.0003% to 0.04% of platinum; andthe complement to 100% being constituted by at least one inorganic refractory oxide.The catalyst can be used in the treatment of exhaust gases from compression ignition engines, in particular from commercial vehicles with an unladen weight of 3.5 metric tons or more.
摘要:
A production process for supported catalysts is described comprising: (a) preparing a coating suspension containing at least one refractory inorganic oxide and at least some of the elements intended to constitute catalytically active phase (A); (b) filling at least part of the open porosity of a support with this suspension; (c) drying the filled support by centrifuging; (d) a thermal treatment of the support to obtain a support coated by a wash coat; (e) optionally impregnating the coated support with a solution containing the rest of, or elements of, catalytically active phase (A); and (f) thermally activating the catalyst. This preparation process is of particular interest in the production of catalysts for treating exhaust gases of internal combustion engines, where the wash coat deposited on a support comprises in particular a refractory inorganic oxide, iron oxide and cerium oxide and, by way of a catalytically active element, at least one noble metal such as platinum, rhodium or palladium.
摘要:
The invention involves the production of a catalyst that contains (1) at least one refractory inorganic oxide support, (2) at least one iron oxide, and (3) at least one cerium oxide, (4) at least one metal A, for example, from Groups VIB, VIIB, VIII, and IB of the Periodic System and, optionally (5) at least one compound of metal B, for example, from Groups IA, IIA, the rare-earths group, and Group IVB of the Periodic System, deposited in the form of a porous layer ("washcoat") on a ceramic or metal substrate:(a) atomizing an aqueous suspension of at least one powder of the refractory inorganic oxide, cerium salt, iron salt, and optionally salt of the metal B; and/or A(b) resuspending the resultant powder and adding any remainder or all of the compound of metal B, as well as, optionally at least one bonding agent and, optionally at least one mineral acid or organic acid;(c) coating a ceramic or metal substrate is coated with the suspension obtained in step (b);(d) calcining the resultant coated substrate;(e) impregnating the resultant coated and calcined substrate with any remainder or all of the precursor of metal A; and(f) thermally activating said coated, calcined, and impregnated substrate coming from step (e).
摘要:
The invention relates to a process for conversion of hydrocarbons in the presence of at least one catalyst with controlled acidity, characterized in that the level of activity of said catalyst in isomerization of the cyclohexane is less than 0.10 and/or in that the ratio of toluene hydrogenation activity to the cyclohexane isomerization activity is greater than 10.
摘要:
A non-aqueous liquid composition with an ionic character resulting from the contacting of at least one alkylaluminum dihalide with at least one quaternary ammonium halide and/or at least one quaternary phosphonium halide, said composition being liquid below 80.degree. C., for example, between -70.degree. and +40.degree. C., is useful as a solvent of catalysts for the dimerization, codimerization and oligomerization of olefins.
摘要:
The invention relates to a process for conversion of hydrocarbons in the presence of at least one catalyst with controlled acidity, characterized in that the level of activity of said catalyst in isomerization of the cyclohexane is less than 0.10 and/or in that the ratio of toluene hydrogenation activity to the cyclohexane isomerization activity is greater than 10.
摘要:
Process for hydrotreating a heavy hydrocarbon fraction using a system of switchable fixed bed guard zones each containing at least two catalyst beds and in which whenever the catalyst bed that is brought initially into contact with the feed is deactivated and/or clogged during the steps in which the feed passes successively through all the guard zones, the point of introduction of the feed is shifted downstream. The present invention also relates to an installation for implementing this process.
摘要:
A filtration device placed upstream of a catalytic bed of a reactor functioning in downflow or upflow mode consists of a plurality of baskets containing filtration particles with a principal dimension (dp), said baskets being supported by a base plate fixed to the walls of the reactor, termed the filtration plate, the assembly of baskets covering at least the central portion of the section of the reactor, and forming a filtration bed with height Hp. Application of said filtration device to processes for hydrotreatment, selective hydrogenation or conversion of residues or hydrocarbon cuts with a boiling point higher than 120° C., preferably higher than 250° C.