Copper-ammonium scrubbing

Copper—Liquor Scrubbing. Cuprous ammonium salts of organic acids form complexes with carbon monoxide. 

In some instances, it is preferable to use copper scrubbing to remove the last traces of carbon monoxide in the ammonia synthesis gas. This process usually is carried out at pressures in the range of 1000 to 1500 psi, which are intermediate pressures of the high pressure ammonia synthesis feed compressors. The copper liquor is circulated countercurrent to the synthesis gas, picking up the carbon monoxide as a copper ammonium carbonate-carbon monoxide complex and producing a relatively carbon monoxide-free gas. Methane and argon, however, are not removed they pass on with the hydrogen to the ammonia synthesis units. 

Cuprasol Also called EIC. A process for removing hydrogen sulfide and ammonia from geothermal steam by scrubbing with an aqueous solution of copper sulfate. The resulting copper sulfide slurry is oxidized with air, and the copper sulfate re-used. The sulfur is recovered as ammonium sulfate. Developed by the EIC Corporation, MA, and demonstrated by the Pacific Gas Electric Company at Geysers, CA, in 1979. 

D. The air discharged in the cylinder B is freed from oxygen by the copper and ammonia. The ammonia is removed from the nitrogen by scrubbing the gas from the exit tube with dil. sulphuric acid. W. L. Badger modified the apparatus using also a soln. of ammonia sat. with ammonium chloride. 

The COSORB solvent has a number of advantages over the aqueous solution of cuprous ammonium salts used in the early copper scrubbing process. It operates at low pressure, is unaffected by carbon dioxide and... 

Scrubbing. In this step the dry geothermal steam is contacted with a sulfuric acid solution of copper sulfate. Hydrogen sulfide and ammonia are absorbed to form a precipitate of copper sulfide and a solution of ammonium sulfate and sulfuric acid. Other impurities in the raw steam are also removed by the scrubbing operation. 

Liquid-Solids Separation. A slip stream of the circulating scrubbing liquid is sent to a decanter where it is separated into a concentrated slurry of copper-sulfide solids and a diluted purge stream of clear, acidic copper and ammonium sulfate solution. 

The salt process employs scrubbing of the gas with cuprous ammonium salt solution. Carbon monoxide forms a complex with the solution at high pressure and low temperature in the absorption column. The absorbed pure carbon monoxide is released from the solution at low pressure and high temperature. In the Cosorb process, cuprous tetrachloroaluminate (CuAlCl ) in a toluene medium is used as the absorbing liquid instead of the copper salt solution. A low corrosion rate and low energy consumption are the advantages of the Cosorb process over the previous one. 

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