The method of separation of para-tert-butylphenol from the reaction mixture and the device for its implementation
(57) Abstract:The invention relates to a method of allocation of ALKYLPHENOLS, in particular, para-tert-butylphenol (PTBP) from the reaction mixtures. The method consists in the fact that the vacuum distillation of the reaction mixture alkylation of phenol with isobutylene are in two columns with the Department of phenol and ortho-tert-butylphenol in both columns in the form of distillate and selection of target PTBF in liquid form from the cube of the second column. In addition, commodity PTBF additionally emit in the vapor phase at the level of the plates 1-8 of the second column and from shlemovoy line reboiler of the second column on the additional piping, which is connected to the additional capacitor. The latter is connected by a drain line condensate PTBF with additional collection. An additional capacitor is installed on the pressure altitude in relation to the additional collector and provided with a gas equalizing line connecting the condenser with the case of the second column at the level of the plates 20-39. The technical result is the simultaneous generation in one process cycle of two different products with different contents PTBF, as well as increasing the purity of commodity PTBF from vysokokapit to how the selection of ALKYLPHENOLS, in particular, para-tert-butylphenol from the reaction mixtures.In organic synthesis is widely known how the selection of ALKYLPHENOLS, in particular, para-tert - butylphenol from the reaction mixtures, providing para - tert-butylphenol with a purity of 95-99%. For example, a known method of extraction of ALKYLPHENOLS from the acidic reaction mixture containing phenol, para-tert-butylphenol (PTBP), ortho-tert-butylphenol (ATBF) and 2,4-di-tert-butylphenol (2,4 DTBP) by a three-stage vacuum distillation to produce in the first column of distillate-phenol, the output of the system, and the cubic product containing PTBF, OTBF and 2.4 DTBF, which share in the second column on the distillate containing OTBF and phenol, the output of the system, and CBM product containing PTBF, OTBF and 2.4 DTBF, which share in the third column on CBM product containing OTBF and 2.4 DTMF output from the system on the decomposition, and the distillate-PTBF (U.S. patent N 3422157, N. class. 260-624, publ. 14.01.69 year). Purity para-tert-butylphenol obtained in this way, reaches up to 95-99%.The disadvantage of this method is the low yield of the target products due to their significant decomposition in the allocation process. In addition, the presence of three rectifica the selection of a mixture of alkyl phenols, containing phenol, PTBF, OTBF and 2.4 DTBP by multi-stage flash distillation, in which the initial mixture is subjected to a single evaporation with subsequent separation of the mixture obtained in the first rectification column on the distillate containing phenol, OTBF and MTBF output from the system, and CBM product containing PTBF and 2.4 DTBF, which share in the second column on the distillate-PTBF and CBM product-2,4 DTBP (ed. St. USSR N 979319, ál. 07 With 39/06, C 07 C 37/34, publ. 07.12.82,, bull. N 45).The disadvantages of this method are the high energy consumption of the process associated with the need for evaporation PTBF inevitable hit PTBF in vacuum creating equipment with its subsequent crystallisation directly from the vapour phase, leading to clogging of the equipment, availability of unusable products that require further processing or destruction. In addition, the known methods are focused on processing alkylphenolic mixtures with high content of heavy impurities, including catalyst dust and acids derived from the alkylation reactor. Thanks to the introduction of new catalysts with high activity, selectivity and durability at the present time, the composition of reaction who I am. Therefore, obtaining para-tert-butylphenol is carried out using a simplified scheme of the separation of the reaction mass.Closest to the proposed group of inventions (prototype) that implements a simplified scheme of allocation PTBF, is a method for the production of para-tertiary butylphenol, described in the "technical regulations for the production of para-tertiary butylphenol" Closed joint stock company "Novokuibyshevsk petrochemical company, 2000, Obtaining PTBF is conducted using two distillation columns under vacuum. Both columns are equipped with condensers and boilers. In the first column is separated in the form of distillate parts of phenol, OTBF and negligible amounts PTBF. In the second column occur final distillation of phenol and ATBF and allocation of commodity PTBF in the form of a bottom liquid in the collection. This method is less energy intensive compared to the above, in addition, the number of unusable waste is also reduced. Purity allocated para-tert-butylphenol is 95-99%.However, the disadvantage of this method is that in addition to the main substances in the bottom liquid are present not only phenol and ATBF in neznacit: 2,4 DBF and substances which products adverse reactions; oligomerization of isobutene, as well as thermal and catalytic degradation of shared components of the mixture in areas of high temperatures in distillation the boilers. The presence of more high-boiling compared to PTBF impurities affects the fundamental qualitative characteristics of commodity PTBF, such as the concentration of the basic substance, the crystallization temperature, chromaticity. The presence of these impurities is often a barrier for use PTBF obtained by this method, in the pharmaceutical industry, in the production of various polymers and plasticizers.The objective of the invention is to increase the degree of purification commodity para-tert-butylphenol from high-boiling impurities without the use of methods associated with the selection PTBF as the top product (distillate) distillation columns, as well as providing simultaneous receipt of the second column of the two types of para-tert-butylphenol: PTBF with a purity of 96.5-97% intended for production butylphenol-formaldehyde resins, and PTBF with a purity of 99%, intended for use in the pharmaceutical industry.The task of resmae alkylation of phenol with isobutylene and a device for implementing this method.The proposed method of allocation of para-tert-butylphenol from the reaction mixture alkylation of phenol with isobutylene consisting of phenol, PTBF,OTBF, 2,4 DBF and heavy impurities, includes a vacuum distillation in two columns with the Department of phenol and ATBF in both columns in the form of distillate and selection of target PTBF in liquid form from the cube of the second column, as well as additional selections PTBF in the vapor phase at the level of the plates 1-8 of the second column and from shlemovoy line reboiler of the second column, and the steam flows condense in the secondary condenser.A device for implementing this method includes two vacuum distillation column equipped with kovovymi boilers, while the second column is supplied by a pipeline output commodity para-tert-butylphenol from the cube columns, connected with the collection, in addition, the second column is further provided with a lateral pipelines selection vapors PTBF level plates 1-8 corps columns and sampling vapor PTBF of shlemovoy line reboiler of the second column, these pipelines connected to the additional capacitor, the latter is connected by a drain line condensate PTBF with additional collection, and Doobie gas equalizing line, connecting an additional capacitor with the case of the second column at the level of the plates 20-39.The invention is illustrated in the diagram of the proposed device.The drawing shows two distillation columns 1 and 2, provided with capacitors 3 and 4 and boilers 5 and 6. Column 2 is further provided with a capacitor 7, pipe 8 lateral sampling of vapor phase PTBF, pipeline 9 selection gratuitous phase PTBF of shlemovoy line 10 of the boiler 6, gas equalizing line 11 connecting the capacitor 7 with the body of the column 2 at the level of the plates 20-39. Commodity PTBF is directed through the pipe 14 to the collector 12 through line 15 condensate drain PTBF in additional proceedings 13. CBM product from the column 1 is column 2 to line 16.The proposed method of allocation of para-tert-butylphenol is implemented with the help of the device is as follows. Separation of the reaction mixture alkylation of phenol with isobutylene consisting of phenol, para-tert-butylphenol, ortho-tert-butylphenol, 2,4-di-tert - butylphenol and heavy impurities is carried out by distillation in two sequential vacuum columns 1 and 2. Alkylate is fed into the column 1, which is casaglia impurities. Heating of the column 1 is performed by the heater 5. A pair of phenol from the top of the column 1 goes to the condenser 3. CBM product of the column 1 by a pump (not shown) is supplied by pipeline 16 in column 2 for selecting columns in the cube PTBF containing heavy impurities by a final distillation of phenol and OTBF. Heating of the column is produced by the boiler 6. A pair of phenol from the top of column 2 enter the condenser 4. VAT product of column 2 representing PTBF with a purity of 96.5-97%, in line 14 by pump (not shown) is supplied to the collector 12. This para-tert-butylphenol meets the requirements of raw materials for the production butylphenol-formaldehyde resins, but does not meet the requirements of PTBF the pharmaceutical industry and the production of various polymers and plasticizers due to the presence of high-boiling heavy impurities. To increase the purity of the commodity para-tert-butylphenol from high-boiling impurities, primarily from 2.4 DBF, non-ferrous and heavy resin through a pipeline 8 output part of para-tert-butylphenol in its vapor phase from the intermediate section distant part of column 2 in the area 1-8 plates with subsequent condensation of the vapor in the condenser 7. However pneumatologia effect selection vapors PTBF from the intermediate section of the column through the pipeline 8 is combined with the selection of vapor PTBF by pipeline from 9 shlemovoy line 10 of the boiler 6. For the Department only color and retinoid impurities enough to output vapor PTBF only shlemovoy line of the boiler. Vapours of the product discharged through the pipeline 9, practically do not contain phenol and OTBF.Thus, from the side of the pipe 8 are selected pair with a basic substance content of 99% and a mixture of phenol and OTBF to 1%. From shlemovoy line pipe 9 couples do with the content of the main substance of 99% and a mixture of 2,4 DTBF. The presence of phenol and OTBF leads to decrease the crystallization temperature of the finished product, which is one of the major determinant of quality. A mixture of 2,4 TBF no effect on this indicator. By varying quantities of vapor entering the condenser 7 of the pipes 8 and 9, it is possible to provide reduction in the total flow as volatile impurities (phenol and OTBF) and heavy impurities (2,4 DBF, resins and color) to 1% or less. Communication, which is given steam flow, can be equipped with special devices for capturing gone droplets of liquid containing heavy impurities. While pipelines 8 and 9 can be combined into a single pipeline, lateral pair PTBF in the capacitor 7 and to run separate (vari is store 7, as a driving force for vapor suction, is provided without installing additional vacuum pump through a communication steam space of the condenser 7 by volume distillation column 2 gas equalizing line 11 in one of the sections of the concentration of the column at the level of the plates 20-39. Thus is solved also the problem of protecting the driving crystals vacuum communications. Drainage of the condensed PTBF from the condenser 7 to the collector 13 is performed without installing additional pump due to the fact that the capacitor 7 installed on barometric altitude relative to the collector 13. The selection of steam flow through pipelines 8 and 9 is in the amount of 5-30% of the number of PTBF entering the column. Pairs taken from shlemovoy line 10 of the boiler 6, have a composition close to equilibrium relative to a bottom of the liquid and, accordingly, contain smaller amounts of high-boiling components and a higher concentration of the basic substance (up to 99%), which means the improvement of consumer properties of the product. This stream after condensation is a liquid PTBF flowing in additional proceedings 13. Simultaneously, the waste liquid of column 2 representing PTBF with pure is in selection PTBF in the vapor phase and in the liquid, you can control the composition of these flows so as not to degrade the quality of the cubic product to undesirable values, at the same time given that the different consumption MTBF imply a different level of requirements to its quality.The proposed group of inventions allows you to provide for simultaneous generation in one process cycle of two different products with different contents of para-tert-butylphenol, to increase the degree of purification commodity PTBF from high-boiling impurities without the use of methods associated with its selection as distillate, and provide the opportunity to further reduce the content of undesirable impurities by mixing steam flows in the secondary condenser and the changes in their quantitative ratios. 1. The method of separation of para-tert-butylphenol from the reaction mixture alkylation of phenol with isobutylene consisting of phenol, para-tert-butylphenol, ortho-tert-butylphenol, 2,4-di-tert-butylphenol and heavy impurities, including vacuum distillation in two columns with the Department of phenol and ortho-tert-butylphenol in both columns in the form of distillate and selection of target para-tert-butylphenol in liquid type level plates 1-8 of the second column and from shlemovoy line reboiler of the second column, after these steam flows condense in the secondary condenser.2. A device for implementing the method according to p. 1, comprising two vacuum distillation column equipped with kovovymi boilers, in which the second column is supplied by a pipeline output commodity para-tert-butylphenol from the cube columns connected with a collector, characterized in that the second column is further provided with a lateral pipelines selection vapors para-tert-butylphenol-level plates 1-8 corps columns and sampling vapor para-tert-butylphenol from shlemovoy line reboiler of the second column, these pipelines connected to the additional capacitor, the latter is connected by a drain line condensate para-tert-butylphenol with an additional collection, moreover, an additional capacitor is installed on the pressure altitude in relation to the additional collector and provided with a gas equalizing line connecting the condenser with the case of the second column at the level of the plates 20-39.
< / BR>where R is a tertiary CnH2n+1c n=4-8, 10 and Deut - C10H21
SUBSTANCE: plate comprises base with openings that receive valves made of plates provided with holes. The caps underlie the holes. The height of the caps increases toward the plate opening. The caps point to the direction opposite to that of the plate opening.
EFFECT: enhanced efficiency.