TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The product gas component is methane (CH4) and the gas mixture is comprised of natural gas. Greater than about 90 mol.% of the CH4 in the gas mixture is recovered in the product gas stream. The microporous adsorbent is comprised of an 8-ring zeolite. The 8-ring zeolite has a Si to Al molar ratio of 1:1 to 1000:1. The 8-ring zeolite is selected from deca-dodecasil-3R (DDR), Sigma-1 or ZSM-58. The 8-ring zeolite is in the form of zeolite crystals which are uniform in size. The first target gas component is carbon dioxide (CO2) or nitrogen (N2) and the second target gas component is hydrogen sulfide (H2S). The first microporous adsorbent material is comprised of an 8-ring zeolite and the second microporous adsorbent material is comprised of a stannosilicate. The blocking agent is selected from polymers, microporous materials, solid hydrocarbons, or liquids. The blocking agent is a liquid selected from amines, aromatics such as 1,3,5 trimethylbenzene, branched saturated hydrocarbons, or liquid hydrocarbons having carbon numbers of 5 to 60. The gas mixture is comprised of an liquefied natural gas (LNG) boil-off gas or an LNG flash gas. The first microporous adsorbent material has a greater selectivity than the second microporous adsorbent material for a first target gas component over the product gas component of the gas mixture. The first microporous adsorbent material has a greater selectivity than the second microporous adsorbent material for the first target gas component of the gas mixture over the product gas component of the gas mixture, and the second microporous adsorbent material has a greater selectivity than the first microporous adsorbent material for a second target gas component over the product gas component of the gas mixture. Less than about 15 vol.% of the open pore volume of the adsorbent contactor comprises pore sizes greater than about 20 angstroms. Preferred Apparatus: The microporous adsorbent is comprised of a stannosilicate. The adsorbent contactor is comprised of a first adsorption zone comprising a first microporous adsorbent material which is in fluid contact with a second adsorption zone comprising a second microporous adsorbent material, where the composition of the first microporous adsorbent material is different from the composition of a second microporous adsorbent material. The adsorbent contactor is comprised of parallel flow channels and the surfaces of the parallel flow channels contain particles of a thermal mass material having a higher capacity of heat adsorbtion than the microporous adsorbent material. The adsorbent contactor contains both mesopores and macropores and where at least some of the mesopores and macropores are occupied with a blocking agent of an effective size so that it is small enough to fit into a mesopore but too large to fit into a micropore. The electric generator is shaft coupled to the turboexpander. The compressor is shaft coupled to the turboexpander. At least a portion of the electrical energy produced by the electric generator is used to power a compressor. The compressor is used to compress at least a portion of the waste gas stream to a pressure of at least 1000 psi. EXAMPLE - No suitable example given.