Abstract: A process for production of acrylic acid by the gas phase catalytic oxidation of acrolein with molecular oxygen in the presence of a catalyst, characterized in that the catalyst is a metal oxide catalyst containing as the metal elements Mo, V, Cu and X in a ratio of 12 : 0.1-16 : 0.1-8 : 0.01-12 as the number of atoms (wherein X represents at least one element selected from the group consisting of Fe, Co, Ni and Mg), whereby acrylic acid can be produced at a greatly lowered reaction temperature in a markedly increased yield with an improved perpass yield.

Abstract: A process for the selective removal of nitrogen oxides from waste gases containing sulfur oxides as well as nitrogen oxides, which comprises contacting the waste gases with a catalyst comprising active metal oxides consisting of vanadium oxide and at least one of molybdenum oxide and tungsten oxide as a catalytically active component and .alpha.-alumina having a specific surface area of 0.3 to 12 m.sup.2 /g and a pore volume of 0.1 cm.sup.3 /g or more as a carrier wherein the atomic ratio of the vanadium, molybdenum, tungsten and aluminum contained in the carrier alumina isV.sub.12-x-y Mo.sub.x W.sub.y Al.sub.zwherein 0.ltoreq.x.ltoreq.8, 0.ltoreq.y.ltoreq.5, 0.3.ltoreq.x + y.ltoreq.8 and 40.ltoreq.z.ltoreq.480, in the presence of ammonia of 0.3 to 4 mol on the basis of 1 mol of nitrogen oxides contained in the waste gases at a temperature of 150.degree. to 700.degree. C.

Abstract: A process for selective removal of nitrogen oxides from waste gases containing 1,500 ppm or less (gas volume) of nitrogen oxides by contacting the waste gases with a metal oxide catalyst containing vanadium oxide and at least one of molybdenum oxide and tungsten oxide with an atomic ratio of the oxide forming elements of:V.sub.12-x-y Mo.sub.x W.sub.yWherein 0.ltoreq.x.ltoreq.8, 0.ltoreq.y.ltoreq.5 and 0.3.ltoreq.x + y.ltoreq.8, at a temperature of 150.degree. to 700.degree. C in the presence of 0.3 to 4 mol of ammonia (on the basis of 1 mol of the nitrogen oxides).

Abstract: In the production of acrylonitrile by a vapor phase reaction of propylene, ammonia and oxygen at an elevated temperature, a process which comprises contacting propylene, ammonia and oxygen with a catalyst composition comprising a catalyst system of the formula: Tl.sub.a P.sub.b Mo.sub.c Fe.sub.d Bi.sub.e X.sub.f O.sub.g wherein X represents one or more of the metals, Ni, Mg and Co, and a, b, c, d, e, f and g represent respectively the relative number of atoms of each component; provided that when c is 12, a is 2 or less, but not 0; b is 0 to 5; d is 0.1 to 5; e is 0.1 to 5; f is 2 to 15; and the value of g depends on the number of the other atoms and is usually from 38.3 to 81.5.

Abstract: A process for the selective removal of nitrogen oxides from waste gases containing nitrogen oxides, which comprises contacting the waste gases with a metal oxide catalyst having the following formula:V.sub.x A.sub.y O.sub.zwherein V is vanadium; A is at least one element selected from the group consisting of copper, zinc, tin, lead, titanium, phosphorus, chromium, iron, cobalt and nickel; x and y are each a numeral of 0.5 to 12; and z is a numeral of 1 to 60, at a temperature of 150.degree. to 800.degree. C in the presence of ammonia.

Abstract: A method for treating ammonia-containing gases for removing ammonia therefrom, which comprises contacting the ammonia-containing gases with a metal oxide catalyst having the following formula:Cr.sub.x A.sub.y O.sub.zwherein Cr is chromium; A is at least one element selected from the group consisting of tin, antimony, vanadium, cobalt, silver, zinc, nickel, titanium, molybdenum, tungsten, sulfur, phosphorus, boron, germanium and zirconium; x is a numeral of 4 to 12; y is a numeral of 0.2 to 8 and z is a numeral of 6.2 to 42, in a vapor phase at a temperature of from 200.degree. to 500.degree. C in the presence of molecular oxygen, and thereby the ammonia is oxidized to harmless nitrogen gas.

Abstract: A catalytic process for the preparation of acrolein by the vapor phase oxidation of propylene which comprises contacting propylene and oxygen with a catalyst composition comprising a catalyst system of the formula:Mo.sub.a Bi.sub.b Fe.sub.c X.sub.d Ni.sub.e Tl.sub.f P.sub.g O.sub.hwherein X is one or more of Mg, Mn and Co and a, b, c, d, e, f, g and h represent, respectively, the number of atoms wherein a is 12, b is 0.1 to 5, c is 0.1 to 5, d is 0 to 12, e is 0.1 to 12, f is 1 or less but not 0, g is 0 to 5 and h depends on the number of the other atoms and is usually from 36 to 89. Acrolein is produced with the use of said catalyst in a high selectivity and an excellent yield per each pass even at a large space velocity.

Abstract: The process involves stripping ammonium nitrogens and organic materials, as gases, which are present in process waste waters to be discharged from plants wherein gases for use in ammonia synthesis are manufactured by reforming hydrocarbons with steam, decomposing the organic materials selectively in the presence of a catalyst at a temperature of about 120.degree. to 400.degree. C., mixing the remaining gases with the flue gases from said plants so as to provide a gaseous mixture having ammonia therein in an amount of about 0.3 to 10 moles per mole of nitrogen oxides present in the flue gases, reacting the gaseous mixture over a catalyst at a temperature of about 150.degree. to 700.degree. C. and oxidizing the unreacted ammonia, if any, in the presence of a catalyst at a temperature of about 150.degree. to 700.degree. C. to render the nocuous substances innocuous.

Abstract: A process for the preparation of acrolein by the vapor phase catalytic oxidation of propylene which comprises contacting propylene and oxygen with a catalyst composition comprising a catalyst system of the formula:Mo.sub.a Bi.sub.b Fe.sub.c Ni.sub.d Tl.sub.e P.sub.f X.sub.g Y.sub.h O.sub.iWherein X is one or more of Mg, Mn and Co, Y is one or more of Cu, Ca, Sr, Zn, Cd, Sn and Pb and a, b, c, d, e, f, g, h and i represent respectively the number of atoms and, when a is 12, b is 0.1 to 5, c is 0.1 to 12, d is 0.1 to 12, e is 1 or less but not 0, f is 0 to 5, g is 0 to 12, h is 0.1 to 12 and i is a number determined by the valence requirements of the other atoms present and from 36.5 to 95.8, provided that b plus c is from 0.2 to 12.5 and d plus g plus h is from 0.2 to 27. The process can provide acrolein in a high selectivity and an excellent single pass yield even at a large space velocity of the propylene feed.

Abstract: A catalytic process for the preparation of acrolein by the vapor phase oxidation of propylene which comprises contacting propylene and oxygen with a catalyst composition comprising a catalyst system of the formula:Mo.sub.a Bi.sub.b Fe.sub.c Ni.sub.d Tl.sub.e P.sub.f X.sub.g Y.sub.h O.sub.i wherein X is one or more of Mg, Mn and Co, Y is one or more of Cu, Ca, Sr, Zn, Cd, Sn and Pb and a, b, c, d, e, f, g, h and i represent respectively the number of atoms, provided that, when a is 12, b is 0.1 to 5, c is 0.1 to 12, d is 0.1 to 12, e is 1 or less but not 0, f is 0 to 5, g is 0 to 12, h is 0.1 to 12 and i is from 36 to 112. By such a process, acrolein is produced in a high selectivity and an excellent yield per each pass even at a large space velocity.