TH89672A - Process for the manufacture of dialkyl carbonates And diol in industry - Google Patents

Abstract

DC60 The objective of this invention has been to provide a specific process capable of making dialkyl carbonates and diol to be produced at an industrial scale of at least 2 t / h and not less than 1.3 t / h. Hours respectively with high specificity And yielding consistently high Over a long period of time through reactive distillation systems using cyclic carbonates and aliphatic monohydric alcohols in the base as the substrate, through which the substrate is continuously fed. Continuing to the multi-stage distillation spear, in which the distillation spear contains catalysts And carrying out reaction and distillation simultaneously in that tower Although there is a lot to offer regarding the process. For the production of dialkyl carbonates And diol through reactive distillation methods, but they exist on a small scale. And low operating time at the laboratory level, and has not disclosed anything with specific processes or equipment that can make mass production with scale. The industry level. According to this invention Has provided a continuous multi-stage distillation tower with Specific structure And the manufacturing process using a continuous multi-step distillation spear, according to that, dialkyl carbonate And diols can be produced on an industrial scale of not less than 2 t / h and not less than 1.3 t / h respectively, each of which has a specificity of not less than 95%, which is suitable not less than 97%. The more appropriate is not less than 99% with a constant period of not less than 1000 hours, which is suitable not less than 3000 hours, the more appropriate is not less than 5000 hours. The purpose of this invention is to provide a process. Only alkyl carbonates and diols that will be produced at an industrial scale of at least 2 t / h and not less than 1.3 t / h can be made, respectively, with high specificity. And yielding consistently high Over a long period of time through reactive distillation systems using cyclic carbonates and aliphatic monohydric alkaloids in the base as the substrate, the substrate feeding Then continue to enter Continuing to the multi-stage distillation spear, in which the distillation spear contains catalysts And carrying out reaction and distillation simultaneously in that tower Although there is a lot to offer regarding the process. For the production of dialkyl carbonates And diol through reactive distillation methods, but they exist on a small scale. And low operating time at the laboratory level, and has not disclosed anything with specific processes or equipment that can make mass production with scale. The industry level. According to this invention Has provided a continuous multi-stage distillation tower with Specific structure And the manufacturing process using a continuous multi-step distillation spear, according to that, dialkyl carbonate And diols can be produced on an industrial scale of not less than 2 t / h and not less than 1.3 t / h respectively, each with a specificity of not less than 95%, which is suitable not less than 97%. Which is more suitable is not less than 99% with a constant period of not less than 1000 hours, which is suitable not less than 3000 hours, the more suitable is not less than 5000 hours.

Claims (20)

------26/11/2018------(OCR) Page 4 of 4 pages(6) The ratio of the inner diameter D (cm) of the distillation column to the inner diameter d2 (cm) of the liquid outlet corresponds to formula (6);5 < D/d2 ^ 30 (6)13. A continuous multistage distillation column according to claim 12, where d1 and d2 correspond to formula (7); 1 < d 1/d2 < 5 (7)14. A continuous multistage distillation column according to claim 12 or 13, where L, D, L/D, T, D/d1, and D/d2 for the said continuous multistage distillation column correspond to, respectively; 2300 ^ L ^ 6000, 200< D < 1000, 5 — L/D ^ 30, 30 — T — 100, 4 ^ D/d 1 ^ 15, and 7 < D/d2 ^ 2515. A continuous multistage distillation column according to one of the claims 12 through 14, where L, A, L/D, T, D/d 1, and D/d2 for such continuous multistage distillation column correspond to, respectively; 2500 ^ L< 5000,210 < D < 800,7 — L/D ^20,40 — T — 90,5^ D/d 1^13, and 9< D/d2 <2016. A continuous multistage distillation column according to one of the claims 12 through 15, where such continuous multistage distillation column is a distillation column with trays. and/or contained in stages as mentioned above. 17. Continuous multistage distillation column according to claim number 16, where such continuous multistage distillation column is a tray type distillation column with trays as mentioned above. 18. Continuous multistage distillation column according to claim number 16 or 17, where such trays are sieve trays with sieve sections and falling sections. 19. Continuous multistage distillation column according to claim number 18, where the sieve trays have 100 to 1000 holes/square meter in the sieve section. 20. Continuous multistage distillation column according to claim number 18 or 19, where the cross-sectional area of the sieve trays ranges from 0.5 to 5 square centimeters. 1. The process for the industrial production of dialkyl carbonates and diols in which dialkyl carbonates and diols are continuously produced via a reactive distillation system using cyclic carbonates and aliphatic monohydric alcohols as feedstocks, consisting of the following steps: continuous feeding of the feedstocks into a continuous multistage distillation column containing a catalyst; simultaneous reaction and distillation in the said distillation column; continuous extraction of the low-boiling point reaction mixture containing dialkyl carbonates produced from the upper part of the distillation column in gaseous form; and continuous extraction of the high-boiling point reaction mixture containing diols from the lower part of the distillation column in liquid form, where (a) the said continuous multistage distillation column consists of a structure with a cylindrical nozzle of length L (cm) and inner diameter D (cm) and with an inner layer containing The number of stages is n, and it consists of a gas outlet with an inner diameter d1 (cm) at the top of the tower or the upper part of the tower near the top, a liquid outlet with an inner diameter d2 (cm) at the end of the tower or the lower part of the tower near the end, and at least one inlet provided in the upper and/or middle part of the tower below the gas outlet. and at least a second inlet which is provided in the middle and/or lower part of the tower above the liquid outlet, where (1) the length L (cm) corresponds to formula (1); 2100 less than or equal to L less than or equal to 8000 (1); (2) the inner diameter D (cm) of the tower corresponds to formula (2); 180 less than or equal to D less than or equal to 2000 (2); (3) the ratio of the length L (cm) to the inner diameter D (cm) of the tower corresponds to formula (3); 4 less than or equal to L/D less than or equal to D (3); (4) the number of steps n corresponds to formula (4); 10 less than or equal to n less than or equal to 120 (4); (5) the ratio of the inner diameter D (cm) of the tower to the inner diameter d1 (cm) of the gas outlet corresponds to formula (5); 3 less than or equal to D/d1 less than or equal to 20 (5); and (6) the ratio of the inner diameter D (cm) of tower to inner diameter d2 (cm) of liquid outlet corresponds to formula (6); 5 less than or equal to D/d2 less than or equal to 30 (6). 2. The process under Claim 1, where the quantity of dialkyl carbonate produced is not less than 2 tons/hour. 3. The process under claim 1 or 2, where the quantity of dialol produced is not less than 1.3 tons/hour. 4. The process according to any one of the claims 1 through 3 such that d1 and d2 correspond to formula (7); 1 is less than or equal to d1/d2 is less than or equal to 5 (7). 5. The process according to any one of claims 1 through 4, where L, D, L/D, n, D/d1, and D/d2 for a continuous multistage distillation column correspond to the following formulas; 2300 ≤ L ≤ 6000, 200 ≤ D ≤ 1000, 5 ≤ L/D ≤ 30, 30 ≤ n ≤ 100, 4 ≤ D/d1 ≤ 15, and 7 ≤ D/d2 ≤ 25, respectively. 6. The process under any one of claims 1 through 5, where L, D, L/D, n, D/d1, and D/d2 for a continuous multistage distillation column correspond to the following formulas; 2500 ≤ L ≤ 5000, 210 ≤ D ≤ 800, 7 ≤ L/D ≤ 20, 40 ≤ n ≤ 90, 5 ≤ D/d1 ≤ 13, and 9 ≤ D/d2 ≤ 20, respectively. 7. A process pursuant to any one of claims 1 through 6, whereby such a continuous multistage distillation column is a distillation column with such trays and/or packing as described. 8. The process under claim 7, whereby the continuous multistage distillation column is a tray type distillation column with such trays as inner layers. 9. The process under any one of the claims 7 to 8, where the tray is a sieve tray with a sieve section and a falling section. 10. The process pursuant to claim 9, where the sieve has 100 to 1000 holes/m² in the sieve portion of the material. 11. The process pursuant to claim 9 or 10, where the cross-sectional area of the sieve tray is in the range of 0.5 to 5 cm². 12. A continuous multistage distillation column for transesterification operations between cyclic carbonate aliphatic monohydric alcohols and distillation. The continuous multistage distillation column consists of: a cylindrical proboscis with length L (cm) and an internal diameter D (cm); an inner side containing n stages is provided within the proboscis; a gas outlet with an internal diameter d1 (cm) is provided at the top of the column or in the upper part of the column near the top; a liquid outlet with an internal diameter d2 (cm) is provided at the end of the column or in the lower part of the column near the end; at least one first inlet is provided in the upper and/or middle part of the column below the gas outlet; and at least one second inlet is provided in the middle and/or lower part of the column above the liquid outlet. Where (1) the length L (cm) corresponds to formula (1); 2100 is less than or equal to L less than or equal to 8000 (1); (2) the inner diameter D (cm) of the tower corresponds to formula (2); 180 is less than or equal to D less than or equal to 2000 (2); (3) the ratio of the length L (cm) to the inner diameter D (cm) of the tower corresponds to formula (3); 4 is less than or equal to L/D less than or equal to D (3); (4) the number of steps n corresponds to formula (4); 10 is less than or equal to n less than or equal to 120 (4); (5) the ratio of the inner diameter D (cm) of the tower to the inner diameter d1 (cm) of the gas outlet corresponds to formula (5); 3 is less than or equal to D/d1 less than or equal to 20 (5); and (6) the ratio of the inner diameter D (cm) of the tower to the inner diameter d2 (cm). The liquid outlet corresponds to formula (6); 5 is less than or equal to D/d2 is less than or equal to 30 (6). 13. A continuous multistage distillation column according to claim 12, where d1 and d2 correspond to formula (7); 1 is less than or equal to d1/d2 is less than or equal to 5 (7). 14. A continuous multistage distillation column pursuant to claim 12 or 13, where L, D, L/D, n, D/d1, and D/d2 for such continuous multistage distillation column correspond to the following formulas; 2300 ≤ L ≤ 6000, 200 ≤ D ≤ 1000, 5 ≤ L/D ≤ 30, 30 ≤ n ≤ 100, 4 ≤ D/d1 ≤ 15, and 7 ≤ D/d2 ≤ 25, respectively. 15. A continuous multistage distillation column according to one of the claims 12 through 14, where L, D, L/D, n, D/d1, and D/d2 for the continuous multistage distillation column correspond to the following formulas; 2500 ≤ L ≤ 5000, 210 ≤ D ≤ 800, 7 ≤ L/D ≤ 20, 40 ≤ n ≤ 90, 5 ≤ D/d1 ≤ 13, and 9 ≤ D/d2 ≤ 20, respectively. 16. A continuous multistage distillation column as provided for in any of the claims under Articles 12 through 15, where such continuous multistage distillation column is a column with inner trays and/or packing. 17. A continuous multistage distillation column pursuant to claim Article 16, where such continuous multistage distillation column is a tray distillation column with trays as inner layers. 18. A continuous multistage distillation column as provided for in either Clause 16 or 17, where such trays are sieving trays with sieving and falling portions. 19. A continuous multi-stage distillation column pursuant to claim paragraph 18, with sieves having 100 to 1000 holes/m² in the sieve portion of the substance. 20. Continuous multistage distillation column pursuant to claim 18 or 19, where the surface area of the filter pan is between 0.5 and 5 cm².