The invention relates to an esterification unit (150) and esterification process for producing crude methyl methacrylate (MMA) from methacrylamide (MAM), which enable particularly to improve the yield, meaning that the organics spent acids are low; and at the same time, providing crude MMA with rather good quality, meaning that MMA concentration in crude MMA is rather high and preferably from 50 wt % to 80 wt %. According to the invention, the esterification unit comprises esterification reactors (1, . . . , 5 (or 6) set up in a serial way so that there is a counter current flow between gaseous phase and liquid phase, the liquid phase flowing from first reactor (1) of the series to last reactor (5 (or 6)), and the gaseous phase flowing from reactor to first reactor (1).

The invention relates to an esterification unit (150) and esterification process for producing crude methyl methacrylate (MMA) from methacrylamide (MAM), which enable particularly to improve the yield, meaning that the organics spent acids are low; and at the same time, providing crude MMA with rather good quality, meaning that MMA concentration in crude MMA is rather high and preferably from 50 wt % to 80 wt %. According to the invention, the esterification unit comprises esterification reactors (1, . . . , 5 (or 6) set up in a serial way so that there is a counter current flow between gaseous phase and liquid phase, the liquid phase flowing from first reactor (1) of the series to last reactor (5 (or 6)), and the gaseous phase flowing from reactor to first reactor (1).

The invention relates to an esterification unit (150) and esterification process for producing crude methyl methacrylate (MMA) from methacrylamide (MAM), which enable particularly to improve the yield, meaning that the organics spent acids are low; and at the same time, providing crude MMA with rather good quality, meaning that MMA concentration in crude MMA is rather high and preferably from 50 wt % to 80 wt %. According to the invention, the esterification unit comprises esterification reactors (1, . . . , 5 (or 6) set up in a serial way so that there is a counter current flow between gaseous phase and liquid phase, the liquid phase flowing from first reactor (1) of the series to last reactor (5 (or 6)), and the gaseous phase flowing from reactor to first reactor (1).

Provided is a method for the alcoholysis of an amide. The method comprises subjecting an amide-containing compound to alcoholysis under alkaline conditions using an epoxy compound as an accelerant of alcoholysis, the method comprising: mixing the amide-containing compound, the epoxy compound, a pH adjuster and a solvent to form an alkaline reaction system, the pH of the alkaline reaction system being 7.5-9.5; reacting the alkaline reaction system at 50 C. 150 C. to subject the amide-containing compound to alcoholysis.

Provided is a method for the alcoholysis of an amide. The method comprises subjecting an amide-containing compound to alcoholysis under alkaline conditions using an epoxy compound as an accelerant of alcoholysis, the method comprising: mixing the amide-containing compound, the epoxy compound, a pH adjuster and a solvent to form an alkaline reaction system, the pH of the alkaline reaction system being 7.5-9.5; reacting the alkaline reaction system at 50 C. 150 C. to subject the amide-containing compound to alcoholysis.

Provided is a method for the alcoholysis of an amide. The method comprises subjecting an amide-containing compound to alcoholysis under alkaline conditions using an epoxy compound as an accelerant of alcoholysis, the method comprising: mixing the amide-containing compound, the epoxy compound, a pH adjuster and a solvent to form an alkaline reaction system, the pH of the alkaline reaction system being 7.5-9.5; reacting the alkaline reaction system at 50 C. 150 C. to subject the amide-containing compound to alcoholysis.

Provided is a method for the alcoholysis of an amide. The method comprises subjecting an amide-containing compound to alcoholysis under alkaline conditions using an epoxy compound as an accelerant of alcoholysis.

Provided is a method for the alcoholysis of an amide. The method comprises subjecting an amide-containing compound to alcoholysis under alkaline conditions using an epoxy compound as an accelerant of alcoholysis.

Provided is a method for the alcoholysis of an amide. The method comprises subjecting an amide-containing compound to alcoholysis under alkaline conditions using an epoxy compound as an accelerant of alcoholysis.

There is described a method of reducing polymer tar build-up in the production of methyl methacrylate and/or methacrylic acid by the acetone cyanohydrin process. In the method a stabiliser is contacted with the amide stage reaction medium. The stabiliser includes a hydrocarbon moiety capable of donating a labile hydrogen atom to a methacrylamide derivative capable of reaction with said labile hydrogen atom under the conditions in the said medium. The method herein is especially useful for the continuous production of methyl methacrylate and/or methacrylic acid.