NOVELTY - Converting (I) gaseous lower molecular weight alkanes to liquid higher molecular weight hydrocarbons, comprises: (a) converting at least one constituent (having 2-5 carbons) contained in a feed gas to methane, thus forming a methane-enriched gas from the feed gas, where the methane-enriched gas has a methane fraction greater than a methane fraction of the feed gas; (b) reacting the methane-enriched gas and bromine to form alkyl bromide; and (c) reacting the alkyl bromide (412) in the presence of a catalyst to form liquid higher molecular weight hydrocarbons and a residual gas.    USE - The method is useful for converting gaseous lower molecular weight alkanes to liquid higher molecular weight hydrocarbons (claimed) which are used in liquefied petroleum gas (LPG), olefin and motor gasoline fuels.    ADVANTAGE - The method: is simple and less expensive; produces desirable hydrocarbon liquid products; requires less energy for operation and minimizes production of excessive carbon dioxide as an unwanted byproduct; and produces mixed hydrocarbon product, thus significantly increasing the octane value of the gasoline-range fuel constituents.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) converting (II) gaseous lower molecular weight alkanes to liquid higher molecular weight hydrocarbons, comprising separating at least 3 carbon fractions from a feed gas comprising lower molecular weight alkanes to form at least 3 carbon products and an ethane-rich gas having an ethane fraction greater than an ethane fraction of the feed gas, converting at least some of the ethane in the ethane-rich gas to methane, thus forming the methane-enriched gas from the ethane-rich gas, where the methane-enriched gas has a methane fraction greater than a methane fraction of the ethane-rich gas, and steps (b) and (c) as above per se; and    (2) converting (III) gaseous lower molecular weight alkanes to liquid higher molecular weight hydrocarbons, comprising separating at least 2 carbon fractions from the feed gas comprising lower molecular weight alkanes to form an ethane-rich gas and a first methane-enriched gas, where the first methane-enriched gas has a methane fraction greater than a methane fraction of the feed gas and the ethane-rich gas has an ethane fraction greater than an ethane fraction of the feed gas, converting at least some the ethane in the ethane-rich gas to methane, thus forming a second methane-enriched gas having a methane fraction greater than a methane fraction of the ethane-rich gas, reacting the first and second methane-enriched gases and bromine to form alkyl bromide, and step (c) as above per se.    DESCRIPTION OF DRAWING(S) - The figure shows a block flow diagram illustrating conversion of gaseous alkanes to liquid heavier hydrocarbon products.    Alkane bromination stage (410)    Alkyl bromide conversion stage (412)    Hydrogen bromide separation stage (414)    Hydrogen bromide oxidation stage (416)    Liquid product recovery stage (420)