An improved process can be used for the production of methacrylates, in particular methacrylic acid and/or methyl methacrylate (MMA). Specific embodiments of this process can be used for the safe and efficient production of these products from C-4-based raw materials, in particular those based on isobutylene or tort-butanol as raw materials. With this novel process, it is possible to operate such processes for a longer period of time without any safety or cleaning related shutdowns. This makes it possible to carry out such processes as simple, economic, and environmentally friendly as possible.

An improved process can be used for the production of methacrylates, in particular methacrylic acid and/or methyl methacrylate (MMA). Specific embodiments of this process can be used for the safe and efficient production of these products from C-4-based raw materials, in particular those based on isobutylene or tort-butanol as raw materials. With this novel process, it is possible to operate such processes for a longer period of time without any safety or cleaning related shutdowns. This makes it possible to carry out such processes as simple, economic, and environmentally friendly as possible.

An object of the present invention is to provide a catalyst ensuring that when a gas-phase catalytic oxidation reaction of a material substance is conducted using a catalyst to produce a target substance, the pressure loss and coking are suppressed and the target substance can be produced in high yield. The present invention is related to a ring-shaped catalyst having a straight body part and a hollow body part, which is used when a gas-phase catalytic oxidation reaction of a material substance is conducted to produce a target substance, wherein a length of the straight body part is shorter than a length of the hollow body part and at least at one end part, a region from an end part of the straight body part to an end part of the hollow body part is concavely curved.

An object of the present invention is to provide a catalyst ensuring that when a gas-phase catalytic oxidation reaction of a material substance is conducted using a catalyst to produce a target substance, the pressure loss and coking are suppressed and the target substance can be produced in high yield. The present invention is related to a ring-shaped catalyst having a straight body part and a hollow body part, which is used when a gas-phase catalytic oxidation reaction of a material substance is conducted to produce a target substance, wherein a length of the straight body part is shorter than a length of the hollow body part and at least at one end part, a region from an end part of the straight body part to an end part of the hollow body part is concavely curved.

An object of the present invention is to provide a catalyst ensuring that when a gas-phase catalytic oxidation reaction of a material substance is conducted using a catalyst to produce a target substance, the pressure loss and coking are suppressed and the target substance can be produced in high yield. The present invention is related to a ring-shaped catalyst having a straight body part and a hollow body part, which is used when a gas-phase catalytic oxidation reaction of a material substance is conducted to produce a target substance, wherein a length of the straight body part is shorter than a length of the hollow body part and at least at one end part, a region from an end part of the straight body part to an end part of the hollow body part is concavely curved.

An improved process can be used for the production of methacrylates, in particular methacrylic acid and/or methyl methacrylate (MMA). Specific embodiments of this process can be used for the safe and efficient production of these products from C-4-based raw materials, in particular those based on isobutylene or tert-butanol as raw materials. With this novel process, it is possible to operate such processes for a longer period of time without any safety or cleaning related shutdowns. This makes it possible to carry out such processes as simple, economic, and environmentally friendly as possible.

An improved process can be used for the production of methacrylates, in particular methacrylic acid and/or methyl methacrylate (MMA). Specific embodiments of this process can be used for the safe and efficient production of these products from C-4-based raw materials, in particular those based on isobutylene or tert-butanol as raw materials. With this novel process, it is possible to operate such processes for a longer period of time without any safety or cleaning related shutdowns. This makes it possible to carry out such processes as simple, economic, and environmentally friendly as possible.

A catalytic composition useful for the conversion of an olefin selected from the group consisting of propylene, isobutylene or mixtures thereof, to acrylonitrile, methacrylonitrile, and mixtures thereof. The catalytic composition comprises a complex of metal oxides comprising rubidium, bismuth, cerium, molybdenum, iron and other promoters, with a desirable composition.

A catalytic composition useful for the conversion of an olefin selected from the group consisting of propylene, isobutylene or mixtures thereof, to acrylonitrile, methacrylonitrile, and mixtures thereof. The catalytic composition comprises a complex of metal oxides comprising rubidium, bismuth, cerium, molybdenum, iron and other promoters, with a desirable composition.

A catalytic composition useful for the conversion of an olefin selected from the group consisting of propylene, isobutylene or mixtures thereof, to acrylonitrile, methacrylonitrile, and mixtures thereof. The catalytic composition comprises a complex of metal oxides comprising rubidium, bismuth, cerium, molybdenum, iron and other promoters, with a desirable composition.