A method for preparing C.sub.2 to C.sub.5 paraffins includes introducing a feed stream including hydrogen gas and a carbon-containing gas selected from carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor. Converting the feed stream into a product stream including C.sub.2 to C.sub.5 paraffins in the presence of a hybrid catalyst. The hybrid catalyst includes a microporous catalyst component; and a metal oxide catalyst component selected from (A) a bulk material consisting of gallium oxide, (B) gallium oxide present on a titanium dioxide support material, and (C) a mixture of gallium oxide and at least one promoter present on a support material selected from Group 4 of the IUPAC periodic table of elements.

A method for preparing C.sub.2 to C.sub.5 paraffins includes introducing a feed stream including hydrogen gas and a carbon-containing gas selected from carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor. Converting the feed stream into a product stream including C.sub.2 to C.sub.5 paraffins in the presence of a hybrid catalyst. The hybrid catalyst includes a microporous catalyst component; and a metal oxide catalyst component selected from (A) a bulk material consisting of gallium oxide, (B) gallium oxide present on a titanium dioxide support material, and (C) a mixture of gallium oxide and at least one promoter present on a support material selected from Group 4 of the IUPAC periodic table of elements.

Electric heaters comprising corrosion resistant metals (CRM), and exhaust gas treatment systems incorporating the same, are provided. Exhaust gas treatment systems include selective catalytic reduction devices (SCR) disposed downstream from reductant injectors. Electric heaters can be disposed downstream from reductant injectors, and optionally contiguous with or incorporated with a catalytic composition of the SCR. CRMs resist corrosion to reductant, which includes t ammonia and/or nitrogen-rich substances capable of decomposing into ammonia, such as urea. CRMs include aluminum, chromium, iron, and one or more stabilizers. CRMs can include about 5.0% to about 7.25% aluminum, about 15% to about 25% chromium, up to about 0.30% stabilizers, and a balance comprising iron. Stabilizers can include hafnium, yttrium, and zirconium. Stabilizers can include about 0.001% to about 0.11% yttrium and about 0.001% to about 0.11% Hf.

Electric heaters comprising corrosion resistant metals (CRM), and exhaust gas treatment systems incorporating the same, are provided. Exhaust gas treatment systems include selective catalytic reduction devices (SCR) disposed downstream from reductant injectors. Electric heaters can be disposed downstream from reductant injectors, and optionally contiguous with or incorporated with a catalytic composition of the SCR. CRMs resist corrosion to reductant, which includes t ammonia and/or nitrogen-rich substances capable of decomposing into ammonia, such as urea. CRMs include aluminum, chromium, iron, and one or more stabilizers. CRMs can include about 5.0% to about 7.25% aluminum, about 15% to about 25% chromium, up to about 0.30% stabilizers, and a balance comprising iron. Stabilizers can include hafnium, yttrium, and zirconium. Stabilizers can include about 0.001% to about 0.11% yttrium and about 0.001% to about 0.11% Hf.

Organometallic complexes are described which are useful as pre-polymerization catalysts which may form part of olefin polymerization catalyst systems. The catalyst systems find use in the polymerization of ethylene, optionally with one or more C.sub.3-12 alpha-olefin comonomers. The organometallic complexes are broadly represented by formula I:

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wherein L is a bridging group containing a contiguous chain of atoms connecting P with Cy, wherein the contiguous chain contains 2 or 3 atoms and wherein Cy is a cyclopentadienyl-type ligand. The olefin polymerization catalyst system is effective at polymerizing ethylene with alpha-olefins in a solution phase polymerization process at high temperatures and produces ethylene copolymers with high molecular weight and high degrees of alpha-olefin incorporation. Pre-metallation compounds, metallation processes and synthetic methods to make the organometallic complexes as well as polymerization processes are also described.

A procatalyst for the polymerization of ethylene and optionally one or more alpha-olefins having the structure shown in formula (I) below. Formula (I) is provided. Also provided is a polymerization process using the inventive procatalyst.

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Disclosed are a grain boundary and surface-doped rare earth manganese-zirconium composite compound as well as a preparation method and use thereof. A rare earth manganese oxide with a special structure is formed at grain boundary and surface of a rare earth zirconium-based oxide by a grain boundary doping method so as to increase oxygen defects at the grain boundary and the surface, thereby increasing the amount of active oxygen, improving the catalytic activity of the rare earth manganese-zirconium composite compound, inhibiting high-temperature sintering of the rare earth manganese-zirconium composite compound, and improving the NO catalytic oxidation capability. When the rare earth manganese-zirconium composite compound is applied to a catalyst, the consumption of noble metal can be greatly reduced.

A method for preparing C.sub.2 to C.sub.5 paraffins including introducing a feed stream of hydrogen gas and a carbon-containing gas selected from carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor. Converting the feed stream into a product stream that includes C.sub.2 to C.sub.5 paraffins in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst including a microporous catalyst component; and a metal oxide catalyst component. The metal oxide catalyst component including a metal component present on a metal oxide support material. The metal oxide support material includes at least one oxide of a metal selected from Group 4 of the IUPAC periodic table of elements. The product stream has a C.sub.3/C.sub.2 carbon molar ratio greater than or equal to 4.0.

A method for preparing C.sub.2 to C.sub.5 paraffins including introducing a feed stream of hydrogen gas and a carbon-containing gas selected from carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor. Converting the feed stream into a product stream that includes C.sub.2 to C.sub.5 paraffins in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst including a microporous catalyst component; and a metal oxide catalyst component. The metal oxide catalyst component including a metal component present on a metal oxide support material. The metal oxide support material includes at least one oxide of a metal selected from Group 4 of the IUPAC periodic table of elements. The product stream has a C.sub.3/C.sub.2 carbon molar ratio greater than or equal to 4.0.

In general, disclosed herein are methods for forming hydrogen by use of an ammonia decomposition catalyst system. For instance, a method can include contacting a catalyst system with an ammonia source at a temperature of about 450 C. or lower. The catalyst systems can include a support material and a trimetallic catalyst component carried on the support material and within a reactor. Disclosed catalyst systems can decompose ammonia at relatively low temperatures and can provide an efficient and cost-effective route to utilization of ammonia as a carbon-free hydrogen storage and generation material.