Process for preparation of methyl methacrylate by esterification during oxidation

摘要

The invention relates to a process for preparation of methacrylic acid, comprising the steps: a) providing a feed composition comprising a main compound selected from isobutylene and tert-butyl alcohol and at least one co-compound selected from the group consisting of methanol, dimethyl ether and formaldehyde; b) subjecting the feed composition provided in step a) with at least a first part of said at least one co-compound to a catalytic reaction zone and obtaining an oxidation phase comprising methyl methacrylate and methacrylic acid. The invention also relates a process for preparation of methyl methacrylate, further comprising the step of: c) esterification of at least a part of the oxidation phase obtained in step b), to an apparatus for preparation of methacrylic acid, to an apparatus for preparation of methyl methacrylate, to a process carried out in the apparatus, to methacrylic acid, to methyl methacrylate, to methacrylate esters, to a process for preparation of a polymer comprising at least one methacrylic acid, methyl methacrylate and/or methacrylate ester monomer unit, to a polymer comprising at least one methacrylic acid, methyl methacrylate and/or methacrylate ester monomer, to a process for preparation of a composition, to a composition, to chemical products, and to the use of at least one of methacrylic acid, methyl methacrylate, methacrylate ester, a polymer and/or a composition in chemical products.

主权项

1. A process comprising:
at least partially oxidizing a feed composition comprising (i) a main compound which is at least isobutylene, and (ii) at least one co-compound selected from the group consisting of methanol, dimethyl ether, ethanol, methyl tert-butyl ether, ethyl tert-butyl ether and formaldehyde, in a catalytic reaction zone to obtain an oxidation phase comprising methacrylic acid as the main product, and optionally, esterifying at least a part of the oxidation phase, wherein said process occurs at least partially in the gas phase, the feed composition is obtained by splitting of methyl tert-butyl ether or of ethyl tert-butyl ether, the oxidation takes place in at least two separate oxidation stages, which comprise a first oxidation to form methacrolein as the main product and a second oxidation to form methacrylic acid as the main product.