Catalyst systems are provided, along with corresponding methods, for single stage conversion of synthesis gas to fuel boiling range products with increased selectivity for either naphtha production (C.sub.5-C.sub.9) or distillate production (C.sub.10-C.sub.20). The increased selectivity for naphtha production or distillate production is provided in conjunction with a reduced selectivity for higher boiling range components (C.sub.21+).

Provided is a method for highly efficiently producing highly pure single-walled carbon nanotubes. This method for producing carbon nanotubes by fluidized CVD includes: a step for heating a material (A) to 1200° C. or higher, in which the total mass of Al.sub.2O.sub.3 and SiO.sub.2 constitutes at least 90% of the total mass of the material (A) and the mass ratio of Al.sub.2O.sub.3/SiO.sub.2 is in the range of 1.0-2.3; and a step for bringing a gas, which is present in the environment in which the material (A) is being heated to 1200° C. or higher, into contact with a feed gas to generate carbon nanotubes.

Provided is a method for highly efficiently producing highly pure single-walled carbon nanotubes. This method for producing carbon nanotubes by fluidized CVD includes: a step for heating a material (A) to 1200° C. or higher, in which the total mass of Al.sub.2O.sub.3 and SiO.sub.2 constitutes at least 90% of the total mass of the material (A) and the mass ratio of Al.sub.2O.sub.3/SiO.sub.2 is in the range of 1.0-2.3; and a step for bringing a gas, which is present in the environment in which the material (A) is being heated to 1200° C. or higher, into contact with a feed gas to generate carbon nanotubes.

A supported non-oxidative alkane dehydrogenation catalyst and a method for making and using the same is disclosed. The supported non-oxidative alkane dehydrogenation catalyst can include a vanadium oxide, a rare earth metal oxide, an alkali metal oxide, and a support containing silica and alumina.

A supported non-oxidative alkane dehydrogenation catalyst and a method for making and using the same is disclosed. The supported non-oxidative alkane dehydrogenation catalyst can include a vanadium oxide, a rare earth metal oxide, an alkali metal oxide, and a support containing silica and alumina.

A composite, zone-coated, dual-use ammonia (AMOX) and nitric oxide oxidation catalyst (12) comprises: a substrate (5) having a total length L and a longitudinal axis and having a substrate surface extending axially between a first substrate end (I) and a second substrate end (O); two or more catalyst washcoat zones (1; 2) comprised of a first catalyst washcoat layer (9) comprising a refractory metal oxide support material and one or more platinum group metal components supported thereon and a second catalyst washcoat layer (11) different from the first catalyst washcoat layer (9) and comprising a refractory metal oxide support material and one or more platinum group metal components supported thereon, which two or more catalyst washcoat zones (1; 2) being arranged axially in series on and along the substrate surface, wherein a first catalyst washcoat zone (1) having a length L.sub.1, wherein L.sub.1<L, is defined at one end by the first substrate end (I) and at a second end (13) by a first end (15) of a second catalyst washcoat zone (2) having a length L.sub.2, wherein L.sub.2<L, wherein the first catalyst washcoat zone (1) comprises a first refractory metal oxide support material and one or more platinum group metal components supported thereon; and the second catalyst washcoat zone comprises a second refractory metal oxide support material and one or more platinum group metal components supported thereon; and a washcoat overlayer (G) extending axially from the first substrate end for up to 200% of the axial length of the underlying first catalyst washcoat layer, which washcoat overlayer comprising a particulate metal oxide loading of >48.8 g/l (>0.8 g/in.sup.3), wherein the particulate metal oxide is an aluminosilicate zeolite including at least one of copper, iron and manganese, wherein a total platinum group metal loading in the first catalyst washcoat zone (1) defined in grams of platinum group metal per litre of substrate volume (g/l) is different from the total platinum group metal loading in the second catalyst washcoat zone (2).

A composite, zone-coated, dual-use ammonia (AMOX) and nitric oxide oxidation catalyst (12) comprises: a substrate (5) having a total length L and a longitudinal axis and having a substrate surface extending axially between a first substrate end (I) and a second substrate end (O); two or more catalyst washcoat zones (1; 2) comprised of a first catalyst washcoat layer (9) comprising a refractory metal oxide support material and one or more platinum group metal components supported thereon and a second catalyst washcoat layer (11) different from the first catalyst washcoat layer (9) and comprising a refractory metal oxide support material and one or more platinum group metal components supported thereon, which two or more catalyst washcoat zones (1; 2) being arranged axially in series on and along the substrate surface, wherein a first catalyst washcoat zone (1) having a length L.sub.1, wherein L.sub.1<L, is defined at one end by the first substrate end (I) and at a second end (13) by a first end (15) of a second catalyst washcoat zone (2) having a length L.sub.2, wherein L.sub.2<L, wherein the first catalyst washcoat zone (1) comprises a first refractory metal oxide support material and one or more platinum group metal components supported thereon; and the second catalyst washcoat zone comprises a second refractory metal oxide support material and one or more platinum group metal components supported thereon; and a washcoat overlayer (G) extending axially from the first substrate end for up to 200% of the axial length of the underlying first catalyst washcoat layer, which washcoat overlayer comprising a particulate metal oxide loading of >48.8 g/l (>0.8 g/in.sup.3), wherein the particulate metal oxide is an aluminosilicate zeolite including at least one of copper, iron and manganese, wherein a total platinum group metal loading in the first catalyst washcoat zone (1) defined in grams of platinum group metal per litre of substrate volume (g/l) is different from the total platinum group metal loading in the second catalyst washcoat zone (2).

A selective catalytic reduction catalyst for the treatment of an exhaust gas stream of a passive ignition engine, the catalyst comprising a porous wall-flow filter substrate comprising an inlet end, an outlet end, a substrate axial length (w) extending between the inlet end and the outlet end, and a plurality of passages defined by porous internal walls of the porous wall flow filter substrate; wherein the catalyst further comprises a first coating, said first coating extending over x % of the substrate axial length from the inlet end toward the outlet end of the substrate, x being in the range of from 10 to 100, wherein the first coating comprises copper and an 8-membered ring pore zeolitic material; wherein the catalyst further comprises a second coating, the second coating extending over y % of the substrate axial length from the outlet end toward the inlet end of the substrate, y being in the range of from 20 to 90, wherein the second coating comprises copper, and optionally an 8-membered ring pore zeolitic material; wherein the catalyst optionally further comprises a third coating; wherein x+y is at least 90; wherein y % of w from the outlet end toward the inlet end of the substrate define the outlet zone of the coated substrate and (100−y) % of w from the inlet end toward the outlet end of the substrate define the inlet zone of the coated substrate; wherein the ratio of the loading of copper in the inlet zone, Cu(in), calculated as CuO, relative to the loading of copper in the outlet zone, Cu(out), calculated as CuO, Cu(in):Cu(out), is less than 1:1.

A selective catalytic reduction catalyst for the treatment of an exhaust gas stream of a passive ignition engine, the catalyst comprising a porous wall-flow filter substrate comprising an inlet end, an outlet end, a substrate axial length (w) extending between the inlet end and the outlet end, and a plurality of passages defined by porous internal walls of the porous wall flow filter substrate; wherein the catalyst further comprises a first coating, said first coating extending over x % of the substrate axial length from the inlet end toward the outlet end of the substrate, x being in the range of from 10 to 100, wherein the first coating comprises copper and an 8-membered ring pore zeolitic material; wherein the catalyst further comprises a second coating, the second coating extending over y % of the substrate axial length from the outlet end toward the inlet end of the substrate, y being in the range of from 20 to 90, wherein the second coating comprises copper, and optionally an 8-membered ring pore zeolitic material; wherein the catalyst optionally further comprises a third coating; wherein x+y is at least 90; wherein y % of w from the outlet end toward the inlet end of the substrate define the outlet zone of the coated substrate and (100−y) % of w from the inlet end toward the outlet end of the substrate define the inlet zone of the coated substrate; wherein the ratio of the loading of copper in the inlet zone, Cu(in), calculated as CuO, relative to the loading of copper in the outlet zone, Cu(out), calculated as CuO, Cu(in):Cu(out), is less than 1:1.

A process for preparing a powder support containing alumina and silica or their derivatives for a catalyst of a Fischer-Tropsch type reaction, including stage (a) of preparing a first reactant containing an alumina compound or precursor including a reaction for peptization of an alumina compound or precursor in the presence of an acid, to form solid particles in suspension, stage (b) of preparing a second reactant based on silicic acid and/or on a compound or precursor of silicic acid, including a controlled aging treatment of the silicic acid targeted at its polymerization up to a degree of conversion of the silicic acid of at most 70%, stage (c) of mixing the two reactants in a mixer, and the pH of the first reactant is adjusted to a value not exceeding a given maximum pH threshold.