Abstract: The invention is concerned with a high-density adsorbent comprising a compacted mass of high surface area carbon particles bound together with a binder and defining a network of substantially unobstructed micropores, the mass of carbon particles having been compacted under a pressure sufficient to cause a reduction of about 50 to about 200% in bulk volume of the mass and a corresponding increase of about 50 to about 200% in density, thereby providing a gas storage capacity increase of about 20 to about 100% over that of the high surface area carbon particles in loose or uncompacted form. The high-density adsorbent according to the invention is particularly useful in adsorption storage systems for low-pressure storage of compressed natural gas.

Abstract: A method and apparatus for measuring physical adsorption of a gas by a solid adsorbent are disclosed. Use is made of a capacitance cell in controlled gas flow communication with a sample cell initially under vacuum and containing the solid adsorbent. The capacitance cell is filled with an adsorptive gas at a predetermined pressure and the dielectric constant of the gas at the predetermined pressure is measured to determine a first density value. The gas from the capacitance cell is then allowed to expand into the sample cell for adsorption by the solid adsorbent, whereby an adsorption takes place pressure falls until eqilibrium is established. The dielectric constant of the gas at equilibrium pressure is measured to determine a second density value, and the amount of gas adsorbed by the solid adsorbent is determined from the first and second density values.

Abstract: A method and an apparatus for the precise determination of the compressibility factor of a gas sample are disclosed. Two grating interferometers are coupled together with one interferometer defining a refractive index interferometer adapted to provide a signal of information related to the refractive index of the gas sample and the other interferometer defining a pressure interferometer adapted to provide another signal of information related to the pressure of the gas sample whereby to permit measurement of the refractive index as a function of pressure. Each interferometer is capable of dividing a linearly polarized monochromatic laser beam into a measuring beam and a reference beam and causing the measuring beam and reference beam to travel along respective optical paths extending in close parallel relationship over predetermined optical path lengths.