Abstract: Process for producing olefins from natural gas, the natural gas (2) is mainly fractionated (1) into methane (3) and higher hydrocarbons (4), the latter being then mainly fractionated (17, 20) into propane (9) and ethane (7). The methane (3), admixed with oxygen (6), passes through an oxidation reactor (5), receives the ethane (7) and the obtained mixture passes through a pyrolysis reactor (8). The effluent coming out of reactor (8) receives the propane (9) and the obtained mixture passes through a pyrolysis reactor (10). A hydrocarbon flow comprising olefins (12), more particularly ethylene and propene, is recovered.

Abstract: Process for producing olefins from natural gas. The natural gas is fractionated (1). The methane (3) mixed with oxygen (6) crosses the oxidizing reactor (5), receives the C.sub.2 + hydrocarbons (7) and the mixture crosses the pyrolysis reactor (8). A hydrocarbons flow containing olefins (10) is collected.

Abstract: The invention concerns a process for the oxidative conversion of methane or natural gas to higher hydrocarbons, particularly ethylene and ethane, characterized in that a methane-oxygen mixture is passed over a contact mass consisting of at least one compound pertaining to the family of rare-earth metal carbonates. It concerns particularly the use of rare-earth oxycarbonates, more particularly lanthanum oxycarbonate La.sub.2 O.sub.2 (CO.sub.3), as contact mass.

Abstract: The invention concerns peroxide complexes of metals complying with the general formula LnMXpY, wherein M is a metal selected from groups VIII, IB and VIIB, particularly cobalt, X is an anionic group, for example carboxylate, R is an alkyl, cycloalkyl or arylalkyl group, n=1 or 2, p=0 or 1 and n+p=2.L is a tridentated ligand from the group of 1,3 bis (2-pyridylimino) isoindolines.These complexes are obtained by reaction of a hydroperoxide ROOH with a complex of formula LnMXp. They can be used in oxidizing hydrocarbons to a mixture of alcohols and ketones, either as reactants or as catalysts.They are particularly useful to prepare tert-butanol by oxidation of isobutane in liquid phase, by means of an oxygen-containing gas such as air.

Abstract: Peroxidic complexes of vanadium, niobium or tantalum, wherein the metal is linked to an oxygen molecule carrying two negative charges, are used either as reactants for the oxidation of olefinic substrates or hydrocarbons, or as hydrocarbons oxidation catalysts, particularly for converting olefinic compounds to epoxides or aliphatic or aromatic hydrocarbons to the corresponding alcohols or phenols.