GB953216A - Improvements in and relating to the method of purifying gas - Google Patents

Abstract

A method of purifying an industrial gas by wholly or partially removing at least one of the gas constituents, e.g. acetylene or organic sulphuretted compounds, which are capable of being transformed by either oxygen or hydrogen, comprises injecting water in liquid or vapour form into the gas so that the water content thereof is between 20 and 500 grams/cubic metre, passing the gas and water into contact with a hydrogenating catalyst, and, if desired, an oxidizing catalyst while keeping the temperature of the gas below 300 DEG C., and removing the products of the transformed constituent. The amount of water injected is controlled to ensure that the action of the catalysts is restricted to the desired constituent. Two specific examples are given. In the first, coke oven gas, preheated to 100 DEG C., is passed at 10,000 cu. metres/hour over a hydrogenating catalyst and an oxidizing catalyst in series, after water has been injected into it at 500 to 800 Kg./hour. The catalysts are maintained respectively at 100 DEG to 120 DEG C. (or 130 DEG to 150 DEG C.) and 150 DEG to 180 DEG C. The process may be carried out at atmospheric pressure or at the prevailing gas pressure. In the second example, a gas comprising 27% CO, 3% CH4, 5% N2, and 64% H2 (by volume) and traces of C2H2, heated to 100 DEG to 120 DEG C. is led at 15,000 cu. metres/hour through the catalysts in series after receiving steam at the rate of 300 gms./hour. The C2H2 is transformed to C2H6. The hydrogenating catalyst is preferably a Pt, Pd, Ni or Cr base catalyst, produced, for example, as described in Specification 901,699, and the oxidizing catalyst is preferably a Cu, Mn, Zn, Ag, Co, Fe or Cr base catalyst, produced, for example, as described in Specification 928,766.ALSO:A method of purifying an industrial gas by wholly or partially removing at least one of the gas constituents, e.g. acetylene or organic sulphuretted compounds, which are capable of being transformed by either oxygen or hydrogen, comprises injecting water in liquid or vapour form into the gas so that the water content thereof is between 20 and 500 grams/cubic metre, passing the gas and water into contact with a hydrogenating catalyst, and, if desired, an oxidizing catalyst while keeping the temperature of the gas below 300 DEG C., and removing the products of the transformed constituent. The amount of water injected is controlled to ensure that the action of the catalysts is restricted to the desired constituent. Two specific examples are given. In the first, coke oven gas, preheated to 100 DEG C., is passed at 10,000 cu. metres/hour over a hydrogenating catalyst, and an oxidizing catalyst in series, after water has been injected into it at 500 to 800 kg./hour. The catalysts are maintained respectively at 100 DEG to 120 DEG C. (or 130 DEG to 150 DEG C.) and 150 DEG to 180 DEG C. The process may be carried out at atmospheric pressure or at the prevailing gas pressure. In the second example, a gas comprising 27% CO, 3% CH4, 5% N2, and 64% H2 (by volume), and traces of C2H2 heated to 100 DEG to 120 DEG C. is led at 15,000 cu. metres/hour through the catalysts in series after receiving steam at the rate of 300 gms./hour. The C2H2 is transformed to C2H6. The hydrogenating catalyst is preferably a Pt, Pd, Ni or Cr base catalyst, produced, for example, as described in Specification 901,699, and the oxidizing catalyst is preferably a Cu, Mn, Zn, Ag, CO, Fe or Cr base catalyst, produced, for example, as described in Specification 928,766.