| 摘要 |
The method for obtaining trimethylolpropane from n-butane and formaldehyde in water solution, at the presence of strong-alkali-reaction anion exchangers as catalysts applied as a stationary layer, characterized in that the mixture is so prepared by dissolving n-butane in the post-synthesis mixture (from the previous synthesis) that the n-butane concentration is equal to 3-4% per weight, and then technical formalin is added to the solution, whereas formalin does not include more than 2% methanol per weight, and the amount of formalin is such that the n-butane/formaldehyde ratio per weight is 1:3.5-1:5, and preferably 1:4.0-1:4.5, and then the solution is stirred and left for stratification, and then the undissolved contamination is removed, and the purified synthesis mixture is applied on a catalyst bed in such amount that the catalyst load is 0.4-0.6 moles of n-butane per dm<3> of catalyst, and the flow is equal to the 1.5-2 hours of substitute contact time, and after dosing the material mixture, the catalyst is rinsed with the distillate from the concentration process of trimethylolpropane that contains 0.5-1.5% per weight of formaldehyde, whereas during the synthesis and the rinsing of the catalyst bed, reflux is received all the time and the first part thereof that does not contain reagents is directed as the finished product, and the other part being received before the rinsing finish, is split in two streams, whereas one stream of 60-61% is returned for preparing the synthesis mixture, and the other stream is directed to the trimethylolpropane separation station.
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