| 摘要 |
A method for producing an unsaturated carboxylic acid comprises: (a) contacting, in a reaction zone, an alkane with a catalyst containing a mixed metal oxide, under conditions which produce a product gas comprising the unsaturated carboxylic acid, unreacted alkane and a product alkene; (b) recovering unreacted alkane and product alkene from the product gas; and (c) recycling the recovered unreacted alkane and product alkene to the reaction zone; wherein the mixed metal oxide consists of a material having the formula AaMmNnXxOo wherein A is at least one element selected from the group consisting of molybdenum and tungsten, wherein M is at least one element selected from the group consisting of vanadium, cerium and chromium, wherein N is at least one element selected from the group consisting of tellurium, bismuth and selenium, wherein X is at least one element selected from the group consisting of niobium, tantalum, titanium, aluminum, zirconium, chromium, manganese, iron, ruthenium, c obalt, rhodium, nickel, platinum, bismuth, boron, indium, arsenic, germanium, tin, lithium, sodium, potassium, rubidium, cesium, francium, beryllium, magnesium, calcium, strontium, barium, hafnium, lead, phosphorus, promethium, europium, gadolinium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, gold, silver, palladium, gallium, zinc, praseodymium, rhenium, iridium, neodymium, yttrium, samarium and terbium, wherein 0.25 < a < 0.98, 0.003 < m < 0.5, 0.003 < n < 0.5, 0.003 < x < 0.5 and o is dependent on the oxidation state of the other elements. An analogous method for the preparation of unsaturated nitriles is also disclosed. |
