Abstract: A process for preparing methacrylic acid which comprises carrying out the catalytic vapor phase oxidation of methacrolein with a member selected from the group consisting of air and a molecular oxygen-containing gas in the presence of a novel catalytic oxide composition of the general formulaY.sub.a X.sub.b P.sub.c Mo.sub.d V.sub.e O.sub.fwherein Y is at least one metallic element selected from the group consisting of copper, cobalt, zirconium, bismuth, antimony and arsenic. X is at least one alkali metal element selected from the group consisting of sodium, potassium, rubidium and cesium, and a, b, c, d, e and f represent the atomic ratios of the several elements; and when d is 12, a is 0-10 and b is 0-10, c is 0.1-10, e is 0.1-10, and f is a value that is determined by the valences and atomic ratios of the several elements, with the proviso that the sum of a plus b is greater than zero.

Abstract: A process for preparing methacrylic acid which comprises carrying out the catalytic vapor phase oxidation of methacrolein with a member selected from the group consisting of air and a molecular oxygen-containing gas in the presence of a novel catalytic oxide composition of the general formulaY.sub.a X.sub.b P.sub.c Mo.sub.d V.sub.e O.sub.fWherein Y is at least one metallic element selected from the group consisting of copper, cobalt, zirconium, bismuth, antimony and arsenic, X is at least one alkali metal element selected from the group consisting of sodium, potassium, rubidium and cesium, and a, b, c, d, e and f represent the atomic ratios of the several elements; and when d is 12, a is 0-10 and b is 0-10, c is 0.1-10, e is 0.1-10, and f is a value that is determined by the valences and atomic ratios of the several elements, with the proviso that the sum of a plus b is greater than zero.

Abstract: Copper phthalocyanine of a novel crystal form which by measurement using CuK.alpha. radiation of .lambda. = 1.5418 A.U. shows an X-ray diffraction pattern having peaks at Bragg's angles 2.theta. equal to about 8.6.degree., 17.2.degree., 18.3.degree., 23.2.degree., 25.3.degree., 26.5.degree., and 28.8.degree..

Abstract: A catalyst composition for preparing acrylic acid from acrolein, comprising a catalytic oxide on an inert porous carrier, said catalytic oxide having the composition of the formulaMo.sub.a V.sub.b Z.sub.c W.sub.d Cu.sub.eWherein Z is at least one alkaline earth metal atom selected from the group consisting of beryllium, magnesium, calcium, barium and strontium; a, b, c, d, and e are the numbers of the respective metal atoms; when a is 12, b is 2 to 14, c is 0.1 to 6, d is 0 to 12, and e is 0 to 6, with the proviso that d plus e is not 0,And a process for preparing acrylic acid by the catalytic vapor-phase oxidation of acrolein with a gas containing molecular oxygen in the presence of such catalyst.

Abstract: A process for producing unsaturated carboxylic acids, which comprises oxidizing unsaturated aldehydes in the vapor phase in the presence of a catalyst comprising a catalytic oxide supported on an inert carrier, such catalytic oxide containing metal elements in the atomic ratio Mo:V:Cu:Cr:W of 12:2-14:1-6:0-4:0-12 with the proviso that Cr + W is not 0.