como nucleofilo en el carbono del benzaldehído, realizando una reacción de condensación de Claisen-Schmidt (tipo de condensación aldolica cruzada). Particulares ○ Efectuar una condensación aldólica cruzada. ○ Obtener un producto de uso comercial. Diferencia entre una condensación aldólica cruzada y. Específicos Efectuar una condensación aldólica cruzada. Determinar el rendimiento de la reacción realizada y el punto fusión del producto obtenido.
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Method for producing highly pure trimethylolpropane. The present invention relates to a method of producing trimethylolpropane which is useful as a raw material for polyester resins, alkyd resins, polyurethane resins, polycarbonate resins, plasticizers, lubricating oils, condsnsacion, basis for cosmetics, reactive monomers, etc. Trimethylolpropane hereinafter referred to as “TMP” has been produced by a known two-stage process see for example, DE-A comprising an aldol condensation between n-butyl aldehyde hereinafter referred hereinafter as “NBAL” and formaldehyde in the presence of a basic catalyst and a subsequent crosslinking reaction between the aldol condensation product and formaldehyde in a basic catalyst Cannizzaro.
For example, the two-phase process using sodium hydroxide is expressed by the following reaction scheme.
The liquid reaction mixture from the two-stage process contains a formic acid salt formed during the crossed Cannizzaro reaction. In the method known in the art, the liquid reaction mixture is distilled after removing most of the formic acid salt by a solvent extraction or a hot filtration after condensing and TMP distillate resulting crude is rectified to condensacuon thereby a final TMP with a high purity.
Condensação de Claisen
The Japanese Patent Publication No. Recientemente, el TMP ha empezado a ser ampliamente utilizado y particularmente condensaacion el uso como materia prima para resinas curables con ultravioleta, presentando el TMP una pureza superior a la que antes se ha llegado a requerir. Recently, TMP has come to be widely used and particularly in the use as raw material for ultraviolet curable resins, TMP presenting a higher purity to previously reached require.
However, since TMP after the solvent extraction, the hot filtration, etc. The method proposed in Japanese Patent Publication No. A method of further purification is described in DD-A Therefore, an object of the present invention to provide an industrially advantageous method for producing a highly pure TMP from a crude TMP obtained by a reaction between NBAL and formaldehyde in the presence of a basic catalyst in a two-phase condensation aldol and a subsequent crossed Cannizzaro reaction.
As a result of extensive studies in the production method of TMP to eliminate the above problems, the inventors have found that a highly pure TMP is obtained from a crude TMP by previously removing a component condensaciln high boiling point and an inorganic salt such as sodium formate, the crude TMP, heat-treating the treated TMP condensaciion acidic conditions, and purifying the heat-treated TMP by distillation, etc.
The present invention has been accomplished based on this finding. The present invention relates to a method of purifying a crude TMP obtained by an aldol condensation and a subsequent crossed Cannizzaro reaction of NBAL of formaldehyde in the presence of a basic catalyst. Formaldehyde used in the present invention as starting material can be used as an aqueous solution or solid as aldoliica. The molar ratio of formaldehyde to be used in the method with NBAL is 3.
These basic catalysts may be used alone or in combination of two or more. Para un procedimiento industrial, se prefieren las sales de sodio o potasio. For an industrial process, the sodium or potassium salts are preferred. The basic catalyst is used in an amount of 1. To minimize the occurrence of byproducts and increase selectivity of the objective TMP, preferred set the amount of the basic catalyst according to the reaction conditions. The first stage aldol condensation and the second stage crossed Cannizzaro reaction are usually conducted successively in the same reaction vessel, without differentiating from the operational point of view one another.
The aldol condensation and the subsequent crossed Cannizzaro reaction may be carried out in the presence of water in an amount of 2 to 20 times by weight of NBAL.
File:Cuatro productos reacción aldólica – Wikimedia Commons
The reaction was complete after 0. The product mixture from the reaction of NBAL and formaldehyde is separated, if necessary after removing formaldehyde unreacted by condensation in crude Alrolica and the formic acid salt, obtained as a byproduct during the crossed Cannizzaro reaction by a solvent extraction or hot filtration after condensing.
The solvent for the extraction may include ketones such as methyl ethyl ketone and methyl isobutyl ketone, aldehydes such as NBAL, also serving as material of alcohols such as isobutyl alcohol and isopropyl alcohol, cruzwda esters such as butyl acetate starting, and are typically condsnsacion in a total amount of 0.
The solvent may be used alone or in combination of two or more. In the present invention, before the subsequent heat treatment, a component of high boiling point and an inorganic salt, including the salt of residual formic acid obtained as a byproduct during the crossed Cannizzaro reaction, the TMP crude thus separated was previously removed.
Deactivation is carried out by adding the acid to the crude TMP in an amount 0. After removing the component and high boiling inorganic salt of crude TMP, the resultant TMP distillate is subjected to a heat treatment under acidic conditions. Such an crzada may include mineral acids such as phosphoric acid and sulfuric acid and organic acids such as p-toluenesulfonic acid and methanesulfonic acid.
TMP obtained by the reaction between NBAL and formaldehyde in the presence of basic catalyst in the two-stage process of the aldol condensation and the subsequent crossed Cannizzaro reaction contains the impurities hardly removable by distillation. The impurities are free formaldehyde, condensation products of TMP and formaldehyde, methanol contained in formalin starting, methanol formed during condesnacion crossed Cannizzaro reaction, condensation products of methanol, TMP and formaldehyde, etc.
In addition, formaldehyde remaining in TMP product is not the completely eliminated by aldolicx usual distillation.
The final product quality is adversely affected by the remaining formaldehyde even in a small amount. To completely remove the impurities such as formaldehyde, MDF, etc.
Thus, a highly pure TMP has not been obtained with conventional distillation methods.
It is known that the condensation products mentioned above are thermally alvolica under acidic conditions publication of Japanese Patent No. However, when TMP contains the formic acid salt and the component of high boiling condensation products are decomposed hard by heat treatment in the presence of acid even in an amount equivalent to the amount condebsacion formic acid saltleaving obtained this a highly pure TMP mode. Although the condensation products are decomposed by the heat treatment condenacion excess amount of acid, a colored component from high boiling point, which is difficult to remove TMP by distillation component is formed.
In the present invention, as described above, after first removing the inorganic salt such as sodium formate, and the component of high boiling the crude TMP, the treated TMP is subjected to heat treatment under acidic conditions.
With such heat treatment, the component hardly removable from TMP by distillation is thermally decomposed or chemically combines to form an easily removable component of TMP by distillation.
Particularly, MDF, which is quite difficult to remove by normal distillation becomes easily removable components by the treatment of the invention, thus enabling to obtain a highly pure TMP. In addition, a highly pure TMP is obtained, since the remaining formaldehyde condenses with TMP is to form easily removable Aldolca during one heat treatment under acidic conditions. In the present invention, as the load of distillation column is reduced, the distillation apparatus improved from the economic viewpoint with respect to the structure and operatively allowing it to produce a highly pure TMP advantageously in industrial scale.
The present invention is further explained by reference to the following examples which should not be construed as limiting the scope of the present invention. In the following examples and comparative examples, the content of the remaining formaldehyde in the final TMP product was determined by acetylacetone method, and the color cast APHA color pattern obtained according to JIS K document 6.
After removing the unreacted formaldehyde, the reaction mixture was extracted with methyl ethyl ketone to obtain g of crude TMP containing 1.
The gas chromatographic analysis showed that the purity of TMP obtained was The content of the remaining formaldehyde in the final TMP was 1 ppm.
Ejemplo comparativo 1 Comparative Example 1. Without adding phosphoric acid and without subjecting to heat treatment, g of the distillate mainly comprising TMP by distillation at under a reduced pressure of Pa 1 Torr using a column with Sulzer-packed 10 theoretical stages purified.
The purity of TMP obtained was The content of the remaining formaldehyde in the final TMP was 30 ppm. Ejemplo comparativo aldilica Comparative Example 2.
Then, after further adding The content of the remaining formaldehyde in the final TMP was 3 ppm. Sin embargo, de manera perjudicial el color fundido del TMP final fue tan elevado como However, the cast detrimentally final TMP color was as high as Ejemplo comparativo 3 Comparative Example 3.
Ejemplo comparativo 4 Comparative Example 4. The content of the remaining formaldehyde in the final TMP was 5 ppm.
TMP obtained by purification of crude TMP by the method of the present invention has such a high purity as In the present invention, it is not necessary to use expensive cation exchange resins, etc.
Por tanto, se produce a escala industrial de manera ventajosa un TMP sumamente puro utilizable como materia prima para resinas curables con ultravioleta. Therefore it occurs industrially advantageously a highly pure TMP usable as a raw material for ultraviolet curable resins. Method for producing a trimethylolpropane TMP highly pure comprising the steps of: Method for producing a highly pure trimethylolpropane according to claim 1, wherein component removing high boiling point and the inorganic salt is carried out after deactivating sodium formate present in the crude trimethylolpropane, wherein the deactivation is carried out by means of adding an acid to crude TMP in an amount 0.
A process for the decomposition of polyhydric alcohols in the synthesis of high-boiling by-products formed. A process for obtaining trimethylolpropane-enriched product streams from the secondary streams of trimethylolpropane.
Process for separating alcohols from mixtures of alcohols, water and other compounds. Purification of propylene oxide using an aqueous acetone extractive distillatin agent.