Process for manufacturing formaldehyde from gas containing hydrogen and carbon monoxide

摘要

In the production of formaldehyde by passing a purified mixture of carbon monoxide and hydrogen over nickel, iron, cobalt, copper, platinum or palladium or their oxides under normal pressure and at a temperature of 130-200 DEG C., the catalyst is regenerated by passing a current of nitrogen or oxide of nitrogen periodically over it, the duration of flow of the reaction gas and regenerating gas being respectively 90 seconds (plus or minus 10 seconds) and 30 seconds (plus or minus 5 seconds). The Specification as open to inspection under Sect. 91 (3) (a) describes also the use of other activating gases such as chlorine, bromine or iodine vapour and "sulphuretted and arsenicated gases," and states that other aldehydes, e.g. benzaldehyde, may be produced. In addition, it describes the polymerization of the resulting aldehyde, particularly formaldehyde, into alcohols and carbohydrates, e.g. sugars, starch and dextrin, by exposure to coloured light rays. The polymerization may be effected in the presence of such substances as alkaline-earth oxides which fix the products, e.g. as calcium saccharate. An example is given, according to which formaldehyde vapour is passed into milk of lime in a cylindrical glass receptacle which is surrounded by a sheet-metal cylinder, the inner wall of which may be coloured reddish orange. Electric lamps, whose bulbs are coloured reddish orange, are suspended in the annular space. Alternatively, the bulbs are colourless whilst the glass receptacle is tinted reddish orange. The formaldehyde is thereby converted into calcium saccharate, from which the sucrose is liberated by means of a current of carbon dioxide. This subject-matter does not appear in the Specification as accepted.ALSO:Formaldehyde is produced by passing a purified mixture of carbon monoxide and hydrogen over nickel, iron, cobalt, copper, platinum, or palladium or their oxides under normal pressure and at a temperature of 130-200 DEG C. The catalyst is regenerated by passing a current of nitrogen or oxide of nitrogen periodically over it, the duration of flow of the reaction gas and regenerating gas being respectively 90 seconds (plus or minus 10 seconds) and 30 seconds (plus or minus 5 seconds). An example is given of the conversion of water gas, purified by treatment with an alkaline solution, into formaldehyde by passage over nickel spirals covered with reduced nickel, with periodic reactivation of the catalyst by means of nitrogen. The Specification as open to inspection under Sect. 91 (3) (a) describes also the use of other activating gases such as chlorine, bromine or iodine vapour, and "sulphuretted and arsenicated gases," and states that other aldehydes, e.g. benzaldehyde, may be produced. In addition, it describes the polymerization of the resulting aldehyde, particularly formaldehyde, into alcohols and carbohydrates, e.g. sugars, starch, and dextrin, by exposure to coloured light rays. The polymerization may be effected in the presence of such substances as alkaline earth oxides which fix the products, e.g. as calcium saccharate. An example is given, according to which formaldehyde vapour is passed into milk of lime in a cylindrical glass receptacle which is surrounded by a sheet metal cylinder, the inner wall of which may be coloured reddish-orange. Electric lamps, whose bulbs are coloured reddish-orange, are suspended in the annular space. Alternatively, the bulbs are colourless whilst the glass receptacle is tinted reddish-orange. The formaldehyde is thereby converted into calcium saccharate, from which the sucrose is liberated by means of a current of carbon dioxide. This subject-matter does not appear in the Specification as accepted.ALSO:The Specification as open to inspection under Sect. 91 (3) (a) states that aldehydes, particularly formaldehyde, are polymerized to starch and dextrin by exposure to coloured light rays. An apparatus is described comprising a cylindrical glass receptacle into which the aldehyde is passed, a sheet metal cylinder surrounding the glass receptacle and electric lamps, whose bulbs are coloured reddish orange, suspended in the annular space. Alternatively, the bulbs are colourless whilst the glass receptacle is tinted reddish orange. The interior of the metal cylinder may be tinted the same colour. This subject-matter does not appear in the Specification as accepted.