Abstract: Nitrogen oxides are removed from gas mixtures containing nitrogen oxides and oxygen by adding a reducing agent that is a C.sub.2 to C.sub.6 olefin or an aromatic hydrocarbon such as benzene or toluene, preferably butene-1, and contacting the mixture at 200.degree. to 450.degree. C with a catalyst comprising iridium or a compound thereof supported on a refractory carrier, preferably alumina.

Abstract: Materials consisting essentially of hydrocarbons with at least two straight chain alkyl groups are useful as wax crystal modifiers in petroleum oils, particularly middle distillate fuel oils such as heating oils and diesel fuels. These materials can be prepared by dimerizing .alpha.-olefins, which dimers can be used per se, or can be further derivatized, e.g. polymerized, alkylated on to an aromatic molecule, etc.

Abstract: A catalyst for initiating the spontaneous decomposition of hydrazine and hydrazine nitrate into ammonia, nitrogen and hydrogen comprises ruthenium supported on high-surface area silica, alumina or silica-alumina substrates promoted with oxides of alkalis, alkaline earths, transition elements and rare earths. The catalyst is particularly useful in monopropellant rocket engines and gas generators and is characterized by: high activity when used in either a pulsed or continuous mode, minimal loss in crush strength or surface area after firing and use of non-strategic materials.