NOVELTY - Making an activated carbon adsorbent having a predetermined pore size distribution and surface area, comprises contacting a char with potassium hydroxide for 1 hour at an activation temperature of 700-900 degrees C and potassium hydroxide:carbon ratio of 2-4.5, where the activated carbon adsorbent has a total pore volume of at least 1 cc/g and Brunauer, Emmett and Teller (BET) surface area of at least 2000 m2/g if the potassium hydroxide:carbon ratio is at least 3.    USE - The process is useful for making an activated carbon adsorbent, which is useful in fuel tanks in vehicles, batteries, electrical capacitors, separation and purification devices, catalysts, gas storage devices, molecular sieve devices, water treatment devices, catalyst supports, ion exchange materials comprising chromatography media, methane storage tanks, hydrogen storage tanks, acetylene storage tanks, and for removing forms of soluble metals from liquids and cleanup of gases.    ADVANTAGE - The process: provides activated carbon adsorbent, which has a total pore volume of at least 1 cc/g and Brunauer, Emmett and Teller (BET) surface area of at least 2000 m2/g, and provides methane adsorption of 130 g of methane for each L of activated carbon adsorbent or 200 g of methane for each kg of activated carbon adsorbent (claimed); provides activated carbon material in particulate and briquetted form, where the briquetted form exhibits enhanced volumetric adsorption characteristics; and provides activated carbon adsorbent with enhanced gravimetric storage capacity.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) a pre-mixed feedstock for the production of the activated carbon adsorbent, comprising potassium hydroxide flakes or solution and char at a potassium hydroxide:carbon of 2-4.5; and    (2) a stored methane composition comprising methane adsorbed to an activated methane adsorbent, where the methane is adsorbed at room temperature and a pressure of 35 bar, where the activated carbon adsorbent has BET surface area of 2000 m2/g and a % volume of pores with 10 Angstrom diameters or less of 70-80% and the amount of methane adsorbed is 130 g of methane for each L of activated carbon adsorbent or a total pore volume of at least 1 cc/g, and a % volume of pores with 10 Angstrom diameters or less of less than 60% and the amount of methane adsorbed is 200 g of methane for each kg of activated carbon adsorbent.