摘要:
A multistage tubular reaction system and method for preparing methylol derivatives of an aldehyde includes a tubular reaction system with a plurality of successive reactor stages comprising a plurality of jacketed reaction tubes provided with a cooling system adapted to control flow of a cooling medium through said jacketed reaction tubes. The cooling medium flow is controlled independently in different stages in response to temperature measurements in the reaction system to regulate temperature. In order to further reduce temperature spikes and byproduct generation, aldehyde is stepwise added to the production stream at a plurality of feed ports proximate to reaction tubes equipped with tube inserts to enhance mixing and heat transfer.
摘要:
The present invention provides a process for improving the color of trimethylolpropane including the steps of preparing a crude aqueous solution of trimethylolpropane (TMP) containing color causing impurities, distilling the solution evaporating excess water from the same, extracting the TMP from the solution, and purifying the extracted TMP, the improvement which comprises the steps of adding an alkaline material to the crude TMP solution after the evaporation step to react with the color causing impurities, cooling the TMP solution and then adding an organic acid thereto to partially neutralize the TMP solution and then proceeding with the extraction and purification steps to form TMP with an improved color.
摘要:
The present invention provides a process for improving the color of trimethylolpropane which comprises the steps of a) supplying a crude, aqueous base solution of trimethylolpropane, containing color causing impurities, and having a pH of less than about 9; b) contacting said base solution with an alkaline material for a period of time sufficient to increase the pH of said base solution to greater than 11 and at a sufficient temperature to allow the color causing impurities to react with said alkaline material; c) cooling the resulting solution from step (b) for a sufficient period of time; d) contacting said base solution of step (c) with an organic acid for a sufficient period of time to lower the pH thereof to less than about 9.5; e) extracting the trimethylolpropane from said base solution of step (d ) with an organic solvent; f) separating the trimethylolpropane from said organic solvent; and g) purifying said trimethylolpropane from step f) to form a trimethylolpropane having a phthalic color of less than 0.20 and an acid wash color of less than 8.
摘要:
A method of reclaiming trimethylolpropane from purification residue includes hydrolyzing a purification residue with an aqueous medium in the presence of (i) an acid and (ii) an oxidizing agent. The method is particularly effective to reclaim trimethylolpropane from monolinear-bis-TMP-formal: monolinear bis-TMP-f ormal (MBLF or TMP-BMLF); Formula II: [C 2 H 5 C(CH 2 OH) 2 CH 2 O] 2 CH 2 (II)
摘要:
The present invention provides a process for improving the color of trimethylolpropane including the steps of preparing a crude aqueous solution of trimethylolpropane (TMP) containing color causing impurities, distilling the solution evaporating excess water from the same, extracting the TMP from the solution, and purifying the extracted TMP, the improvement which comprises the steps of adding an alkaline material to the crude TMP solution after the evaporation step to react with the color causing impurities, cooling the TMP solution and then adding an organic acid thereto to partially neutralize the TMP solution and then proceeding with the extraction and purification steps to form TMP with an improved color.
摘要:
A multistage tubular reaction system and method for preparing methylol derivatives of an aldehyde includes a tubular reaction system with a plurality of successive reactor stages provided with a formaldehyde containing feed stream. The system includes multiple feed ports for the staged addition of C2 or higher condensible aldehyde and/or base to the formaldehyde containing stream at a plurality of successive feed points to provide a production stream, which is progressively provided with additional reactants as the production stream advances through the successive reaction stages. Advantages include better temperature control and reduced byproduct formation.