Back to results
US 9,546,148 B2Granted
Process for the production of trioxane from aqueous formaldehyde sources
AssigneeTicona LLC
InventorsMichael Haubs, Jurgen Lingnau, Klaus Kurz
Life of this patent
Estimating the term…
Abstract
The present invention relates to a process for producing cyclic acetal comprising i) preparing a liquid reaction mixture comprising a) a formaldehyde source, b) an aprotic compound and c) a catalyst; wherein the total amount of protic compounds is less than 40 wt.-%, based on the total weight of the reaction mixture; and ii) converting the formaldehyde source into cyclic acetals.
Claims20
A process for producing a cyclic acetal comprising:
- reacting a formaldehyde source in the presence of a cationic catalyst to produce a cyclic acetal, the formaldehyde source comprising a material selected from the group consisting of formaldehyde, paraformaldehyde, and a polyoxymethylene polymer, the cyclic acetal comprising a material selected from the group consisting of trioxane, tetroxane, and mixtures thereof, and wherein the reaction is carried out in a liquid medium comprising a liquid aprotic compound having a boiling point of 120° C. or higher determined at 1 bar, wherein the aprotic compound is selected from the group consisting of organic sulfoxides, organic sulfones, organic sulfonate esters, and mixtures thereof, and wherein the amount of the liquid aprotic compound comprises at least 20 wt % of the liquid medium and wherein the aprotic compound does not chemically react with the formaldehyde source.
A liquid reaction mixture comprising
- a) a formaldehyde source, the formaldehyde source comprising a material selected from the group consisting of formaldehyde, paraformaldehyde, and a polyoxymethylene polymer;
- b) an aprotic compound comprising a sulfur containing organic compound and
- c) a cationic catalyst;
- wherein the total amount of protic compounds is less than 40 wt.-%, based on the total weight of the reaction mixture.
1 more element
A process for producing a cyclic acetal comprising:
- reacting a formaldehyde source in the presence of a cationic catalyst to produce a cyclic acetal, the formaldehyde source comprising a material selected from the group consisting of formaldehyde, paraformaldehyde, and a polyoxymetnyene polymer, and wherein the cyclic acetal comprises a material selected from the group consisting of trioxane, tetroxane, and mixtures thereof, and wherein the reaction is carried out in a liquid medium comprising a liquid aprotic compound having a boiling point of 120° C. or higher determined at 1 bar, wherein to aprotic compound is selected from the group consisting of organic sulfoxides, organic sulfones, organic sulfonate esters, and mixtures thereof, and wherein the amount of the liquid aprotic compound comprises at least 20 wt % of the liquid medium;
- and
- separating the cyclic acetal from the liquid medium by distillation.
A process for producing a cyclic acetal comprising:
- reacting a formaldehyde source in the presence of a cationic catalyst to produce a cyclic acetal, the formaldehyde source comprising a material selected from the group consisting of formaldehyde, paraformaldehyde, and a polyoxymethylene polymer, and wherein the cyclic acetal comprises a material selected from the group consisting of trioxane, tetroxane, and mixtures thereof, and wherein the reaction is carried out in a liquid medium comprising a liquid aprotic compound having a boiling point of 120° C. or higher determined at 1 bar, wherein the aprotic compound is selected from the group consisting of organic sulfoxides, organic sulfones, organic sulfonate esters, and mixtures thereof, and wherein the amount of the liquid aprotic compound comprises at least 20 wt % of the liquid medium, and wherein the catalyst comprises trifluoromethanesulfonic acid, perchloric acid, methanesulfonic acid, toluenesulfonic acid, sulfuric acid, an acid ion-exchange material or mixtures thereof.
Dependencies are inferred from the claim text.