Abstract: Disclosed is a process for the production of maleic anhydride, which comprises: reacting a hydrocarbon with an oxygen-containing gas in the presence of a catalyst; recovering maleic anhydride from the reaction gas; recovering unreacted hydrocarbon from the remaining gas; and returning the hydrocarbon thus recovered to the reactor for re-use, wherein said reaction is effected under the conditions such that the hydrocarbon concentration X (vol %) and oxygen concentration Y (vol) in all the gases to be fed into the reactor, the hydrocarbon conversion Z (t) in the reactor and the oxygen concentration W (vol %) in all the effluent gases from the reactor satisfy the following relationships: Y≧20, X+Y≦70, 1≦Y/X≦5, and 20(Y−10)/X≦Z≦25Y/X or 2≦W≦10.

Abstract: Disclosed is a process for the production of maleic anhydride, which comprises: reacting a hydrocarbon with an oxygen-containing gas in the presence of a catalyst; recovering maleic anhydride from the reaction gas; recovering unreacted hydrocarbon from the remaining gas; and returning the hydrocarbon thus recovered to the reactor for re-use, wherein said reaction is effected under the conditions such that the hydrocarbon concentration X (vol %) and oxygen concentration Y (vol) in all the gases to be fed into the reactor, the hydrocarbon conversion Z (t) in the reactor and the oxygen concentration W (vol %) in all the effluent gases from the reactor satisfy the following relationships:

Abstract: Disclosed is a process for the production of maleic anhydride, which comprises: reacting a hydrocarbon with an oxygen-containing gas in the presence of a catalyst; recovering maleic anhydride from the reaction gas; recovering unreacted hydrocarbon from the remaining gas; and returning the hydrocarbon thus recovered to the reactor for re-use, wherein said reaction is effected under the conditions such that the hydrocarbon concentration X (vol %) and oxygen concentration Y (vol %) in all the gases to be fed into the reactor, the hydrocarbon conversion Z (%) in the reactor and the oxygen concentration W (vol %) in all the effluent gases from the reactor satisfy the following relationships: Y≧20, X+Y≦70, 1≦Y/X≦5, and 20(Y−10)/X≦Z≦25Y/X or 2≦W≦10.

Abstract: A process for producing maleic anhydride is described, which comprises (i) reacting a hydrocarbon with oxygen in a vapor phase in the presence of a catalyst to yield a reaction mixture gas containing maleic anhydride, (ii) bringing the reaction mixture gas into contact with an organic solvent to collect the maleic anhydride in the organic solvent, (iii) separating at least part of the maleic anhydride from the organic solvent, (iv) washing with an aqueous alkali solution at least part of the organic solvent from which maleic anhydride has been separated, and (v) reusing the resultant washed organic solvent and the residual organic solvent for contact with the reaction mixture gas.