The present disclosure relates to a process for stabilizing an antimony ammoxidation catalyst in an ammoxidation process. The process may comprise providing an antimony ammoxidation catalyst to a reactor; reacting propylene with ammonia and oxygen in the fluidized bed reactor in the presence of the antimony ammoxidation catalyst to form a crude acrylonitrile product; and adding an effective amount of an antimony-containing compound to the antimony ammoxidation catalyst to maintain catalyst conversion and selectivity; wherein the antimony-containing compound has a melting point less than 375° C. The present disclosure also relates to catalyst compositions and additional processes using the antimony ammoxidation catalyst stabilized by an antimony-containing compound.

A method for producing an oxide catalyst according to the present invention is a method for producing an oxide catalyst containing Mo, V, Sb, and Nb, the method including: a raw material preparation step of obtaining an aqueous mixed liquid containing Mo, V, Sb, and Nb; an aging step of subjecting the aqueous mixed liquid to aging at more than 30° C.; a drying step of drying the aqueous mixed liquid, thereby obtaining a dried powder; and a calcination step of calcining the dried powder, thereby obtaining the oxide catalyst, wherein, in the raw material preparation step and/or the aging step, precipitation of Nb is facilitated by performing at least one operation selected from the group consisting of the following (I) to (III): (I) in the raw material preparation step, the aqueous mixed liquid is prepared by mixing a Nb raw material liquid containing Nb with a MoVSb raw material liquid containing Mo, V, and Sb, wherein ammonia is added to at least one of the MoVSb raw material liquid, the Nb raw material liquid, and the aqueous mixed liquid such that a molar ratio in terms of NH.sub.3/Nb in the aqueous mixed liquid is adjusted to be 0.7 or more, and in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 50° C.; (II) in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 65° C.; and (III) in the raw material preparation step, the aqueous mixed liquid is prepared by mixing a Nb raw material liquid containing Nb with a MoVSb raw material liquid containing Mo, V, and Sb, wherein a molar ratio in terms of H.sub.2O.sub.2/Nb in the Nb raw material liquid is adjusted to less than 0.2, and in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 50° C.

A method for producing an oxide catalyst according to the present invention is a method for producing an oxide catalyst containing Mo, V, Sb, and Nb, the method including: a raw material preparation step of obtaining an aqueous mixed liquid containing Mo, V, Sb, and Nb; an aging step of subjecting the aqueous mixed liquid to aging at more than 30° C.; a drying step of drying the aqueous mixed liquid, thereby obtaining a dried powder; and a calcination step of calcining the dried powder, thereby obtaining the oxide catalyst, wherein, in the raw material preparation step and/or the aging step, precipitation of Nb is facilitated by performing at least one operation selected from the group consisting of the following (I) to (III): (I) in the raw material preparation step, the aqueous mixed liquid is prepared by mixing a Nb raw material liquid containing Nb with a MoVSb raw material liquid containing Mo, V, and Sb, wherein ammonia is added to at least one of the MoVSb raw material liquid, the Nb raw material liquid, and the aqueous mixed liquid such that a molar ratio in terms of NH.sub.3/Nb in the aqueous mixed liquid is adjusted to be 0.7 or more, and in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 50° C.; (II) in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 65° C.; and (III) in the raw material preparation step, the aqueous mixed liquid is prepared by mixing a Nb raw material liquid containing Nb with a MoVSb raw material liquid containing Mo, V, and Sb, wherein a molar ratio in terms of H.sub.2O.sub.2/Nb in the Nb raw material liquid is adjusted to less than 0.2, and in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 50° C.

A method for producing an oxide catalyst according to the present invention is a method for producing an oxide catalyst containing Mo, V, Sb, and Nb, the method including: a raw material preparation step of obtaining an aqueous mixed liquid containing Mo, V, Sb, and Nb; an aging step of subjecting the aqueous mixed liquid to aging at more than 30° C.; a drying step of drying the aqueous mixed liquid, thereby obtaining a dried powder; and a calcination step of calcining the dried powder, thereby obtaining the oxide catalyst, wherein, in the raw material preparation step and/or the aging step, precipitation of Nb is facilitated by performing at least one operation selected from the group consisting of the following (I) to (III): (I) in the raw material preparation step, the aqueous mixed liquid is prepared by mixing a Nb raw material liquid containing Nb with a MoVSb raw material liquid containing Mo, V, and Sb, wherein ammonia is added to at least one of the MoVSb raw material liquid, the Nb raw material liquid, and the aqueous mixed liquid such that a molar ratio in terms of NH.sub.3/Nb in the aqueous mixed liquid is adjusted to be 0.7 or more, and in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 50° C.; (II) in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 65° C.; and (III) in the raw material preparation step, the aqueous mixed liquid is prepared by mixing a Nb raw material liquid containing Nb with a MoVSb raw material liquid containing Mo, V, and Sb, wherein a molar ratio in terms of H.sub.2O.sub.2/Nb in the Nb raw material liquid is adjusted to less than 0.2, and in the aging step, a temperature of the aqueous mixed liquid is adjusted to more than 50° C.

The present disclosure relates to fluid bed processes that utilize silica particles as a fluidization aid. The process comprises reacting one or more reactants in a reactor comprising a fluid bed to form a product. The fluid bed comprises a catalyst composition comprising a catalyst and an inert additive composition comprising silica particles from 0.5 wt % to 30 wt %, based on the total weight of the catalyst composition. The silica particles are discrete, inert particles that are mixed with the catalyst in the fluid bed.

The present disclosure relates to fluid bed processes that utilize silica particles as a fluidization aid. The process comprises reacting one or more reactants in a reactor comprising a fluid bed to form a product. The fluid bed comprises a catalyst composition comprising a catalyst and an inert additive composition comprising silica particles from 0.5 wt % to 30 wt %, based on the total weight of the catalyst composition. The silica particles are discrete, inert particles that are mixed with the catalyst in the fluid bed.

The present disclosure relates to fluid bed processes that utilize silica particles as a fluidization aid. The process comprises reacting one or more reactants in a reactor comprising a fluid bed to form a product. The fluid bed comprises a catalyst composition comprising a catalyst and an inert additive composition comprising silica particles from 0.5 wt % to 30 wt %, based on the total weight of the catalyst composition. The silica particles are discrete, inert particles that are mixed with the catalyst in the fluid bed.

A process is provided for control of an ammoxidation reactor. More specifically, the process includes controlling an amount of oxygen added to the reactor, steam temperature and linear velocity to minimize reactor temperature deviations.

A process is provided for control of an ammoxidation reactor. More specifically, the process includes controlling an amount of oxygen added to the reactor, steam temperature and linear velocity to minimize reactor temperature deviations.

A process is provided for control of an ammoxidation reactor. More specifically, the process includes controlling an amount of oxygen added to the reactor, steam temperature and linear velocity to minimize reactor temperature deviations.