Patent GB-767751-A (GB)
Title: Production of hydrogen peroxide and ethylene oxide from ethane
IPC: C01B15/024
Filed: 1954-07-19
Abstract: Ethylene oxide and hydrogen peroxide are prepared by a process comprising feeding a mixture of ethane and recycle gas containing substantial quantities of ethane and ethylene into a catalyst-free reaction zone heated to a temperature in the range 450 DEG  to 550 DEG  C. along with such a quantity of oxygen that the mixture contains less oxygen by volume than ethane and less than 15 per cent by volume of oxygen; maintaining the mixture at a pressure above atmospheric up to 100 p.s.i.g. and passing it through the reaction zone for a period up to 2 seconds, the time and temperature being sufficient to effect consumption of less than 65 per cent of the oxygen entering the reaction zone; maintaining the interior surfaces of the reaction zone substantially free of hydrocarbon decomposition products by periodically cleaning the surfaces; and recycling at least a portion of the unoxygenated hydrocarbons and unconsumed oxygen to the reaction zone.  The inner surfaces of the reaction zone are made of materials which have no catalytic effect upon the reaction, e.g. a borosilicate glass or fused boric acid.  The reactor surfaces may be cleaned by periodically treating with hot nitric acid.  The gases leaving the reactor are cooled to condense the hydrogen peroxide formed and are then preferably passed in countercurrent to a low temperature absorption liquid, such as buffered cold water, so as to scrub out condensable oxygenated products from the exit gases.  In the examples ethane and oxygen are mixed with recycle gas containing ethylene and ethane and the mixture is passed through a heated unpacked reactor at a pressure slightly in excess of atmospheric to give a mixture from which, on cooling, hydrogen peroxide with some acetaldehyde and formaldehyde are condensed; the residual gases are treated with a phosphate buffer solution which removes ethylene oxide with some aldehydes, and part of the uncondensable gases are recycled.ALSO:Hydrogen peroxide and ethylene oxide are prepared by a process comprising feeding a mixture of ethane and recycle gas containing substantial quantities of ethane and ethylene into a catalyst-free reaction zone heated to 450-550 DEG C. along with such a quantity of oxygen that the mixture contains less oxygen by volume than ethane and less than 15 per cent by volume of oxygen; maintaining the mixture at a pressure above atmospheric up to 100 psig, and passing it through the reaction zone for a period up to 2 seconds, the time and temperature being sufficient to effect consumption of less than 65 per cent of the oxygen entering the reaction zone; maintaining the interior surfaces of the reaction zone substantially free of hydrocarbon decomposition products by periodically cleaning the surfaces; and recycling at least a portion of the unoxygenated hydrocarbons and unconsumed oxygen to the reaction zone.  The inner surfaces of the reaction zone are made of materials which have no catalytic effect upon the reaction, e.g. a borosilicate glass or fused boric acid.  The reactor surfaces may be cleaned by periodically treating with hot nitric acid.  The gases leaving the reactor are cooled to condense hydrogen peroxide.  The non-condensible gases are separated from the rest and a proportion is returned to the reactor.  In the examples ethane and oxygen are mixed with recycle gas containing ethylene and ethane and the mixture is passed through a heated unpacked reactor at a pressure slightly above atmospheric to give a mixture from which on cooling, hydrogen peroxide with some formaldehyde and acetaldehyde are condensed; the residual gases are treated with a phosphate buffer solution which removes ethylene oxide with some aldehydes; and part of the uncondensable gases remaining are recycled.