Patent GB-1001505-A (GB)
Title: A process for the oxidation of substituted or unsubstituted hydrocarbons
IPC: B01J27/057
Filed: 1962-10-15
Abstract: A process for the oxidation of olefines to diolefines comprises passing them in the vapour phase with oxygen over a hexavalent tellurium catalyst at a high temperature.  The oxygen may be " pure, " diluted with argon, or air.  The tellurium is combined with oxygen, e.g. TeO3, H6TeO6 and preferably further, with Cr, Mo or W, e. hexamolybdotellurates and hexatungstatellurates. A siliceous diluent/support may be provided, and promoters, e.g. As, Se, S, or TeIV added.  The temperatures used are between 325 DEG  and 550 DEG C., the pressures between atmospheric and 500 p.s.i.g., and the contact times between 0.1 and 250 seconds.  The mol. ratio of olefin to oxygen may be 1 : 0.15 to 1 : 15. Example VII describes the oxidation of butene to butadiene over a hexamolybotellurate catalyst. A mixture of butene-1, air and steam is used, having a mol. ratio of 1 : 1 : 6 of butene: oxygen : water, at 491 DEG  C., 4.5 p.s.i.g. and 0.6 sec. contact time.  Specification 909,907 is referred to.ALSO:A process for the oxidation of aldehydes and hydrocarbons comprises passing them in the vapour phase in the presence or absence of an amine at an elevated temperature with molecular oxygen, over a hexavalent tellurium catalyst.  The oxygen may be "pure," air, or diluted with argon.  The tellurium is combined with oxygen, e.g. TeO3, H6TeO6, and further preferably with Cr, Mo or W, the preferred atomic ratio of the latter to tellurium being 6: 1, e.g. hexamolybdotellurate (TeO3.6MoO3), hexatungstatellurate (TeO3.6WO3) and copper hexamolybdotellurate (CuO.TeO3.6MoO3).  A siliceous, preferably silica, support may be provided, comprising 1-80% of the total catalyst weight.  Promoters, e.g. As, S, TeIV, Se may be added, as such, or as oxides or other compounds.  The temperatures used are between 325 DEG  and 550 DEG  C., the pressures between atmospheric and 500 p.s.i.g., and the contact time is between 0.1 and 250, preferably 0.1-5, seconds.  The process is more particularly described wherein the hydrocarbon is an olefin, the mol. ratio of olefin to oxygen being between 1 : 0.15 and 1 : 15, and water vapour may be introduced in a ratio to olefin of between 1 : 1 and 15 : 1. Reaction products may be separated by conventional methods and/or recycled or passed through further oxidation stages, e.g. to form acrylic acid.  Examples I-VI describe the oxidation of propylene to acrolein by air or oxygen-argon mixture, with water vapour, under the influence of hexamolybdotellurate, copper hexamolybdotellurate or hexatungstatellurate catalysts on silica (Ludox), and compare the results with those from copper mirror, bismuth molybdate and tetravalent tellurium catalysts. Further examples describe the oxidation of butene to butadiene and methybutene to methacrolein over hexamolybdotellurate catalysts.  Besides the oxidation of olefins to aldehydes, the process is suitable for the oxidation of olefins, acetylenes or aldehydes to carboxylic acids, of acetylene to acetaldehyde, of olefines and aldehydes in the presence of amines to nitriles, and of benzene to maleic anhydride or fumaric acid. Specification 909,907 is referred to.ALSO:A catalyst for the vapour phase oxidation of aldehydes and hydrocarbons by oxygen (see Divisions C2 and C5) comprises hexavalent tellurium in combination with oxygen, e.g. TeO3, H6TeO6, and preferably further, with Cr, Mo or W, e.g. hexamolybdotellurate (TeO3,6MoO3), hexatungstatellurate (TeO3,6WO3) and copper hexamolybdotellurate (CuO,TeO3,6MoO3).  A diluent/support may be provided, which may be aluminous or siliceous (preferably siliceous, especially silica) e.g. alumina, bauxite, porocel, alundum, aloxite, or carborundum, silicon, silicon carbide, ceramic materials, clays, fire brick, or charcoals and active carbons.  These may comprise 1-80% of the total catalyst weight. Promoters, e.g. As, S, Se, or TeIV may be added, as oxides or other compounds, or free.  Supports of metal may be employed, of e.g. copper, iron, nickel, cobalt, aluminium or brass spelter, in the form of spheres, chunks or shavings, or the catalyst may be sintered with the metal.  The catalyst may be prepared using any suitable source and method, e.g. by physical mixture of TeO3 and support, with or without an oxy-compound of Cr, Mo or W (e.g. tungsten or molybdenum oxides, or cobalt or nickel molybdate, or phosphomolybdate), or by calcining salts of telluric acid or molybdotellurates (e.g. <FORM:1001505/B1-B2/1> ).  Specification 909,907 is referred to.