The method of decomposition gidroperekisi cumene acid catalyst to phenol and acetone
(57) Abstract:Essence: phenol and acetone are produced by the acid decomposition product of cumene oxidation - technical gidroperekisi hornless in the reactor back-mixing with a vortex motion of the products of the reaction. Used in this catalytic system in the form of 0.3 - 0.5 wt.% solution of sulfuric acid in acetone and the degree of decomposition of gidroperekisi cumene regulated depending on the temperature difference at the ends of the "device control decomposition". Increases the selectivity of the reaction. At the last stage of the process decomposition of residual dimethyl-phenylcarbinol and peroxide of Dicumyl lead with speed reduction of the pH by entering into the water system in the amount of 0.5 - 6% (based on the reaction mass decomposition gidroperekisi. 5 C.p. f-crystals, 2 tab., 1 Il. The invention relates to the production of phenol and acetone "Kukolnik method, in particular to the improvement of the process of decomposition gidroperekisi hydroperoxide (CHP) acid catalyst to phenol and acetone.Decomposition GPK - exothermic reaction with an exothermic effect 486 kcal/kg [Kruglov B. D., Golovenko B. I. Joint production of phenol and acetone. M: Goskomizdat, 1963] and usually x2">In such reactors the original CCP continuously introduced (usually immediately before the reactor) in the reaction mass decomposition (PMP), continuously circulating in a system consisting of a reactor (can be as hollow and reactor-heat exchanger, heat exchanger, circulation pump and connecting piping. In this circulation system (usually in the suction pipe of the circulation pump) is continuously introduced an acid catalyst (as well as additives that affect the selectivity of the decomposition process) in an amount to provide the desired rate of decomposition of the CCP.Heat exothermic decomposition reaction of the CCP is perceived reaction mass decomposition and is discharged from the system through the heat exchanger. The required temperature of the process is supported by the ratio of the number of input GPK and circulating PMP and the feed rate of the refrigerant in the heat exchanger.Ready for further processing PMP continuously removed from the system (usually after a reactor or heat exchanger) in an amount equal to the amount of the components (GCA, acid catalyst, additives).One of the most important characteristics of such non-isothermal react PMP in the system decomposition). Depending on the design elements of the system and of the type used in heat exchanger refrigerant volumetric feed rate of the original CCP typically ranges from 2 hours and below that corresponds to the residence time of the reaction products in the system 30 minutesStay PMP in the system decomposition has a significant impact on the selectivity of the acid decomposition of the technical code of civil procedure, which is present as an impurity reactive product - dimethylphenylcarbinol (DMPC). In PMP in addition to the target of phenol and acetone appears alpha methylsterol (AMC), peroxide, di -, has been studied (MPC), cumylphenol (KF), the dimer of alpha-methylstyrene (DAS), which are formed and react according to reaction (see tab. 1).In taken from the reactor system back-mixing of the RAP target products are phenol, acetone and AMS, and the other side DMFC, KF, DAS and MAC and submitted as part of technical GPK-acetophenone (ACP) - are the basic components of phenolic resins - low waste production.Thus cumylphenol and MPC reduce commodity phenol.When the process of decomposition of technical gidroperekisi under mild conditions (low temperature, low concentration kisli reaction of 2,4 and 5, but the amount of phenolic resin is not reduced, since the lower output of the KF and DAS abundantly compensated by the increased number of MPC, which in cubes rectification columns for the separation of PMP on commodity products by known methods, thermally decomposes with the formation of resins and polyphenols.
The output of valuable AMC is 30-40% of capacity. When the process of decomposition in harsh environments (high temperature, high concentration of acid catalyst, the lack of moderators and diluents) mainly occur reactions 1, 2, 4, 5, which leads to the same high yields of phenolic resin and low yield of AMS.Known [Levstein Century A. Decomposition of gidroperekisi of cumene in the reactor reduced volume. - Refining and petrochemicals, N 4, 1971] position, indicating that the decomposition of the CCP acid catalyst, carried out during his stay in the system decomposition is not more than 3 min (volumetric feed rate of the original GPK - 20 h-1), increases the selectivity of the process to implement practically not possible, as is usually achieved volumetric rate lower required due to the high ekzotermicheskie process.For the first time about the possibility of stephenathome selectivity remained low.Modern methods of acid decomposition of the CCP for phenol and acetone solve the problem of increasing the selectivity of the process (reduce output low phenolic resin and increase the output of the securities act) by a stepwise transformation of the CCP in the products of its decomposition, but with regard to the formation and decomposition of the MPC (the United Kingdom patent 2100730, class C 07 C 37/08; U.S. patent 5254751, 4310712, CL 568-798; U.S. patent 4207264, 3187052, CL 568-385; U.S. patent 2748172, 3367352, CL 568-768).At the same time in the reactor of the inverse mixing decompose the CCP under mild conditions, achieving flow in the main reactions 1 and 3, while reactions 2, 4, and 5 are to a small extent, and the output from the reactor system reverse mixing PMP subjected to short-term (this is possible because the reaction of 2 and 6 is not exothermic) heat followed by cooling to terminate the reaction at the maximum output of the AMC. During a short heating PMP mainly reactions proceed 2 and 6, and reactions 4 and 5 have time to go to a small extent.The output of valuable AMC in this way, the process of decomposition increases significantly, and education components of the phenolic resin is reduced.The invention is directed to the improvement of the certain object on the totality of symptoms and the achieved technical effect (prototype) is using the Decomposition product of cumene oxidation (patent UK 2100730, class. C 07 C 37/08), in which the product of the oxidation of cumene containing CPC and DMFC is decomposed by an acid catalyst in the first stage at low temperatures, decreasing the concentration of the CCP to 0.5-5% and turning a large part DMFC in EQS. In the second stage, the concentration of CPC drops below 0.4 percent. In the third stage, the MPC is decomposed at a higher temperature for a short period of time at AMS, phenol and acetone, and the remaining DMFC also turns into AMS. The concentration of MPC at the third stage is controlled and the reaction is terminated by cooling, when 0.5 to 5% MPC remains nerazlozhimoi for maximising output AMS.The disadvantages of this method are.1. High risk process in the first stage (especially industrial version) because of the presence in the system recycle stream to the reactor reverse mixing 0.5 to 5% non-CCP. While mixing with the newly CPC receives an additional 0.5 - 5% of the CCP with the cooled stream circulating PMPs.Each percent of CPC decomposition as part of PMP causes it to heat on 9oC (it is easy to calculate, if the specific teploemkosti PMP 0.55 kcal/kgoC and an exothermic effect of the decomposition of the CCP equal 486 kcal/kg, centrali acid catalyst, the quantity and quality of input GPK, changing the amount of added water, the process temperature changes) can cause autocatalytic decomposition of all present in the reactor system back-mixing of the CCP (as input again, and returned with a chilled PMP) that will lead to a sharp rise in temperature in the system (at 45oC in the case of selection of the reactor system reverse mixing RAP with a residual content of GPC, equal to 5%).Possible output system of mode, a sharp increase in temperature could lead to increased pressure in the system (boiling PMP) with the emergency consequences (known precedents).In industrial installations to ensure the safety of the process carefully control the content of the CCP, PMP, coming chilled in the reactor back-mixing, preventing its values above 0.3 wt.% (lower limit of detection of the CCP used the Express method).The phenomenon, when the chilled recycle stream PMP quick analysis discover the CCP (i.e. more than 0.3 wt.%), is called "incomplete decomposition" and when it is found the system decomposition stops supply in the source code of civil procedure. Again, the system starts to work only p is nnow work site reactor back-mixing in a hazardous environment "incomplete decomposition", moreover, virtually uncontrolled.2. To achieve the necessary moderation process known method (Academy of Sciences of the USSR. The chemistry of peroxides. M.: Publishing house of the USSR Academy of Sciences, 1963) provides an input to the system of the reactor opposite the mixing of additional (excess resulting from reactions 2 and 3) water, defining it in the range 0.4-4.5 wt.%.However, excessive water in the reactor system reverse mixing inhibits not only the reaction of dehydration DMFC (reaction 2), but the reaction is MAC, and this is undesirable, because to get the most out of valuable AMC at the last stage of the way is better it is through the reaction of 6, since it is known that the rate of formation of the components of the phenolic resin (DAS, KF) with the participation of the AMC, the resulting decomposition MPC (reaction 6), significantly less than the rate of those same reactions involving AMS obtained by dehydration DMFC (reaction 2). When this excess water makes the reaction of 2 and at the final stage of the process (the known method provides even supply additional quantities of catalyst at this stage).H. At the final stage known method of carrying out reactions 2 and 6 kratkovremenna (pH, the temperature around the apparatus structural flow, which does not allow to achieve the maximum possible output AMS due to braking reaction 2, increasing from the beginning to the end of the structural unit of flow) concentration of AMS, which is also, as the increase in the concentration of water inhibits this reaction.The disadvantages mentioned above, inherent and otherwise taken into account as similar, some differences which consist in the application of acetone for additional moderation process and the acetone is introduced into the reactor system reverse mixing until the molar ratio of acetone and phenol (1,1-1,5): 1. In taken into account a method for monitoring process used a device called a "mini-reactor", through which passes a part taken from the reactor system back-mixing of the RAP and due to the heat decomposition of residual CPC temperature PMP on the way out of this "mini-reactor" is higher than at the entrance. Moreover, this decomposition takes place in the same conditions as the samples of this PMP from the reactor system back-mixing. This device but gives some information about the number of CCP in the exhaust from the reactor system back-mixing of the RAP, but extremely dangerous in case of decrease is), because this decrease in the rate of decomposition decreases the temperature difference at the ends of the "mini-reactor" and will be perceived as a decrease in the concentration of CPC in selected PMP and staff will take measures to further reduce the degradation rate of the CCP in the system of the reactor back-mixing, instead of taking measures to improve this speed.In addition, it should be noted that in the known methods provide a significant amount of inert cumene in the original CCP (preferably 10-18%), and cumene, increasing (as a diluent) selectivity of the decomposition process of the CCP at the division PMP trademark products by known methods, will require their provision of additional energy.The aim of the invention is to achieve security of the decomposition process and its control in the first stage, as well as increasing the selectivity of this process at all stages.The declared objective is achieved by the fact that :
1. acid catalyst (in this case, sulfuric acid) is introduced into the circulation system of the reactor back-mixing in the form of a 0.3-0.5% solution in acetone;
2. Circulating in the reactor back-mixing of the reaction mass decomposition in the discharge line circensian known structural relationships, necessary tightening of the thread), (Plonowski A. N. and other Processes and apparatus of chemical technology. M. : Chemistry, 1968), which provides rotational movement of the PMP over the entire height of the reactor. When this is sent to the decomposition of the initial CCP introduced in pricebuy area of the lower part of the reactor (in the zone of maximum speed post PMP).As it turned out, the introduction to the decomposition of the CCP sulfuric acid in the form of a 0.3-0.5% of its solution in acetone and the application of the described reactor moderated by the decomposition of the CCP to the extent that additional moderators (water, acetone) and diluents (cumene) system decomposition the first stage do not need to enter. In the exhaust from the reactor system reverse mixing PMP concentration of undecomposed CCP does not exceed 0.3 wt.%, the content of the MPC reaches maximum values, and the content of heavy reaction products slightly (to trace). No extra water (in excess of the resulting reaction 2, C) is not difficult for reaction 3, which also increases the selectivity of the process;
3. For continuous automatic control process in the first stage implemented method, based on equitime, for what was all introduced into the reactor system reverse mixing an acid catalyst (in this case, the sulfuric acid solution in acetone) before entering into the system is mixed in a special tube, called a "pipe control decomposition", with a small amount (for example, 1 t/h) chilled PMP recycling coming in the same tube with the discharge of the pump. As a result, the mixture passing through the "tunnel control decomposition, the concentration of sulfuric acid will increase the number of times a multiple load system reactor reverse confusion over the source of the CCP (for example, if the load on the CCP equal to 10 t/h, and in the "pipe" is 1 t/h PMP, the content of acid in the mixture is 10 times higher than in the reactor system back-mixing and present in circulating cold PMP residual CPC warranty is extended with the release of a corresponding amount of heat. Mounted on the ends of the "pipe control decomposition" thermocouple continuously record the temperature difference T . Thus T is proportional to the residual of the CCP, PMP, entering the suction of the circulation pump. For example, if transported by the pipe control decomposition" 1 t/h PMP contains 1 wt.% the residual of the CCP, the difference BR> G = G1+ G2= 1198 kg/h
G1= 1 t/h = 1000 kg/h input PMP
G2= 198 kg/hour - enter the acid solution in acetone
c = 0.55 kcal/kgoC is the heat capacity of the mixture
T = Q/Gc = 4860/11980,55 = 7,4oC
If PMP is 0.3 wt.% CCP, respectively, T is equal to 7,40,3 = 2,2oC.The apparatus detects T , is connected to the automation system process, its control and lock. Volume "pipe control decomposition should provide a residence time therein of a mixture of RAP and the catalyst is not less than 1 min in This way, security, manageability of the process at the first stage and increase selectivity.To improve the selectivity of the decomposition MAC and residual DMFC in part taken from the reactor system back-mixing of the RAP by short-time heating of this PMP then cooled implemented technique, allowing to increase the output of act on this final stage by reducing the content of residual DMFC.In order to reduce the speed of formation of products (DAS and KF) in the structural unit of flow (the phone is ideal displacement) type the extension (in excess of the amount coming from a PMP selected from sisk was, as a result of this stepwise reduction of the pH along the length of the structural unit stream comprising PMP taken after cooling for further processing decreases the concentration of undecomposed residual DMFC with a corresponding increase in the output of the AMC.The speed of decomposition MPC (reaction 6) as it turned out, in the area of machine structural flow with increased water concentration is not reduced.The literature has not been previously described method of decomposition gidroperekisi cumene acid catalyst, in which the security process at the greater of its selectivity and controllability contents nerazlozhimoi CCP, taken from the reactor system reverse mixing PMP would be less than 0.3 wt.% (in the known methods of 0.5 - 5 wt.%, attained by the use of a special catalyst system in the form of a 0.3-0.5% solution of sulfuric acid in acetone, hollow reactor reverse mixing with a vortex (rotational) movement in it a PMP and a special device - the "pipe control decomposition", which allows continuous, automatic mode to control and regulate the process at this stage.As previously described the process the final stage of RA is then cooled, in which to improve the selectivity proceeding with the reactions would have been subjected to the process with step by lowering the pH by adding water (or any other moderator) after a certain time after the beginning of this final stage.The mentioned circumstances allow us to state that the claimed object corresponds to the first criterial feature of the invention is a novelty.On the other hand the comparison of the known characteristics of the prototype method (as well as other taken into consideration, methods and characteristics of the proposed technical solution does not allow to predict the observed positive effect of a sharp decline in residual CPC in taken from the reactor system reverse mixing PMP (process safety), and improving the selectivity of the process at all stages.This allows us to conclude that the claimed object is not obvious from the well-known in the industry prior art and, therefore, it has the second criterion characteristic of the invention, an inventive step.Finally, this technical solution through certain structurally-g-d case, the enterprises of organic synthesis), and therefore, it has the third criterion a symptom of the invention and industrial applicability.The proposed method is illustrated by the scheme shown in the drawing, which presents the following components and parts: 1 - reactor with tangential entry PMP, 2 - heat exchanger-refrigerator circulating PMP, 3 - pump, 4 - vessel for preparation of a solution of sulfuric acid in acetone, 5 - pump PMP at the final stage, 6 - heat exchanger-heater, 7 - structural unit of flow, 8 - heat exchanger-refrigerator, 9 - a collection of the final product of the decomposition of the CCP, the 10 "pipe control decomposition".The process of acid decomposition of technical CCP under this scheme is as follows Technical CCP, containing also DMFC, ACF, the residual cumene, some organic acids, is fed continuously to the bottom pricebuy part of the hollow vortex reactor 1, in the lower part of which is tangentially injected stream is cooled to 35 - 45oC circulating PMPs containing 0,005-0,015 wt.% (50 - 150 ppm) acid catalyst. The reactor 1 is a hollow vertical cylindrical apparatus (described constructive condition for winding p is sliczna, under what pressure does the device (in our case, is the device volume 8 m31.2 m diameter and operating at atmospheric pressure).Mix sour PMP entered the CCP, good mixing at the point of introduction into the reactor (diameter input of the CCP in the reactor thread PMP rotates with a frequency of 1200 rpm) and vigorously contacting due to the rotational movement, is the reactor 1 from the bottom up.Heat exothermic decomposition reaction of the CCP is perceived by the mass introduced circulational PMP, resulting in a temperature PMP increases to 50-75oC in the upper part of the reactor.Heated PMP with a small residual content of the CCP from the upper part of the reactor 1 is continuously supplied to the heat exchanger 2 where it is cooled before 35-44oC. Chilled PMP after the heat exchanger 2 is divided into two streams. Part of the PMP, equal to the amount of the components (GCA, the catalyst in the form of 0,3-0,5% solution of sulfuric acid in acetone), the pump 5 is supplied to the subsequent stage of decomposition, and the main part - the circulation PMP is fed to the suction of the circulation pump 3 and then tangentially in the lower part of the reactor 1. Acid catalyst (0,3-0,5% solution of sulfuric acid in acetone) in the share of the suction pipe of the pump 3) circulation, mixing in a special pipe 10 ("pipe control decomposition") from 1 t/h PMP from the discharge side of the pump 3, resulting in acidity in the pipe on the order (the number of times a multiple input system of the CCP, in t/h) higher than in the system decomposition. The volume of this pipe should ensure that the residence time of 1 t/h of a mixture of PMP with the input catalyst is not less than 1 min (in our case it is a pipe with a diameter of 80 mm and a length of 5 m).Residual CPC present in the circulation PMP submitted to the suction of the pump 3 (a is selected from the system by pump 5), this excess of acid catalyst to be dissolved, and the selected heat will heat up the mixture in the pipe, which is recorded as the difference between the temperature of the mixture at the beginning and end of pipe control decomposition".The sulfuric acid solution in acetone (0.3 to 0.5 wt.%) prepared in a special vessel 4 where it enters into the suction pipe of the circulation pump 3 through the pipe control decomposition" 10.The number you enter in the system acid catalyst is adjusted automatically according to the set temperature difference ( T ) on the pipe control decomposition".Sufficient selectivity and process safety are provided at T 0,3 - 2,1oat T = 0,7-1,6oC.Upon reaching T the extreme values of the alarm and lock.Selected from the circulating system PMP, containing not more than 0.3 wt.% nerazlozhimoi CCP, pump 5 under the pressure of 2-3 atmospheres (gauge) is supplied to the steam heat exchanger-heater 6 (preferably of the "tube-in-tube or multi-pass shell-and-tube to exclude local overheating), where it is heated to 100-130oC and at this temperature in the apparatus structural thread 7 (in our case it is a pipe with a diameter of 0.35 m and a length of 15 m), which she (PMP) is for 3-15 min (depends on temperature and concentration of acid catalyst), during which undergo dehydration reaction of residual DMFC (reaction 2) and the decomposition MPC (reaction 6) to desired values, and reactions 4 and 5 have time to go to a small extent.When the maximum output AMS reaction is terminated by tahaliyani PMP held device 7 to 35-50oC in the heat exchanger-refrigerator 8, then cooled PMP enters the collector 9 and further processing by known methods (neutralization and isolation of commodity components).To improve the selectivity of the decomposition process DMFC is about 1/4 of the total length of the device), in the device 7 is put water in the amount of 0.5 to 6 wt.% (usually 1-2 wt.%) from the mass passing through the apparatus PMP.Below are examples of the decomposition of technical CCP in the system, the corresponding shown in the drawing.Example 1. Technical GIC containing cumene in the number of 0.77 wt.%, the acetophenone of 0.52 wt.%, dimethylphenylcarbinol 5,16 wt.% and Gidropress cumene 93,55 wt. % of 9 t/h is fed continuously into the reactor 1, where in the amount of 280 t/h enters and sour circulation PMP with the concentration of sulfuric acid of 0.01 wt.%, and the temperature of the 35oC.Heated (in the decomposition reaction of the CCP) to 58oC PMP from the reactor 1 through the heat exchanger-refrigerator 2, where it is cooled to 35oC, is fed to the suction of the circulation pump 3 and then again in the reactor 1.Acid catalyst (in the form of 0.45%-aqueous solution of sulfuric acid in acetone) in an amount of 198 kg/h is fed continuously into the suction pipe of the pump 3 through the pipe control decomposition" 10.Through the same pipe 10 with the discharge side of the pump 3 is fed 1 t/h circulating PMPs.The temperature difference ( T ) at the ends of the "pipe control decomposition is 1(oC, which corresponds to the end is from the line of circulation (after the refrigerator 2) and the pump 5 is supplied to the next stage of decomposition.The molar ratio present in PMP acetone to phenol is of 1.062:1.Entering the pump 5 PMP was analyzed for the content of MAC DMFC, ACF, AMC, DAS, and CF.The results are shown in table. 1
Example 2. Technical GIC containing cumene in the amount of 0.99 wt.%, the acetophenone of 0.45 wt.%, dimethylphenylcarbinol 4,74 wt.% and Gidropress cumene 93,82 wt.%, by the same procedure as in example 1, in the amount of 9.4 t/h is introduced into the reactor system back-mixing. The temperature of the refrigerated PMP 35oC, the temperature of the top of the reactor 1 59oC, the amount fed to the reactor PMP 280 t/h, the number you enter in the system 0,38%-aqueous solution of sulfuric acid in acetone 198 kg/h, the content of acid in the circulating PMP 0,008 wt.%. (80 ppm). From the system is taken 9,598 t/h to the next stage.The temperature difference between the pipe 10( T ) 1.5oC, which corresponds to the concentration of the CCP, PMP, equal to 0.21 wt.%. The molar ratio present in PMP acetone to phenol is 1059:1.The result of the analysis shown in the table. 1.Example 3. Technical GIC containing cumene in the amount of 1.0 wt.%, the acetophenone 0.43 wt. % dimethylphenylcarbinol 4.3 wt.% and Gidropress cumene 94,37 wt.% the same schema is SUP>oC, the temperature of the top of the reactor 1 is 58oC, the quantity introduced into the reactor PMP 280 t/h, the number you enter in the system 0,37%-aqueous solution of sulfuric acid in acetone 198 kg/h, the content of acid in the circulating PMP - 0,0082 wt.% (82 ppm), of the system is taken 9,198 tons/HR PMP to the next stage.The temperature difference between the pipe 10 ( T ) 0.8oC, which corresponds to the concentration of the CCP, PMP, is equal to 0.11 wt.%.The molar ratio present in PMP acetone to phenol is 1,061:1.The result of the analysis shown in the table. 1.Example 4. The resulting decomposition of the CCP in example 1, the reaction mixture by the pump 5 under a pressure of 2 MPa is pumped sequentially through the steam heater 6 where it is heated to 106oC, the structural unit of stream 7, water cooler 8 where it is cooled to 40oC and flows into the collector 9.Stay PMP apparatus 7 is 9.4 minutes Through the 2.4 min, after receiving heated to 106oC PMP in the apparatus 7 (PMP goes 1/4 of the total length of the device) in PMP is introduced 90 kg/h of water, resulting in a total water content of the PMP (added water and the water formed as a result of reactions 2 and 3) sestavljalca analysis shown in the table. 2.Example 5. The resulting decomposition of the code of civil procedure to example 2, the reaction mixture by the pump 5 under a pressure of 2 MPa is pumped sequentially through the steam heater 6 where it is heated to 112oC, the structural unit of stream 7, water cooler 8 where it is cooled to 40oC and flows into the collector 9.Stay PMP apparatus 7 is 9 minutes In the same point apparatus 7, as in example 4, is introduced 94 kg/h of water, resulting in a total water content of the PMP is 1.63 wt.%.Unit 9 selected sample and analyzed for the content of impurities.The result of the analysis shown in the table. 2.Example 6. The resulting decomposition of the code of civil procedure to example 3, the reaction mixture by the pump 5 under a pressure of 2 MPa is pumped sequentially through the steam heater 6 where it is heated to 110oC, the structural unit of stream 7, water cooler 8 where it is cooled to 40oC and flows into the collector 9.Stay PMP apparatus 7 is 9.4 minutesIn the same point apparatus 7, as in example 4, is inserted 95 kg/h of water, resulting in a total water content of the PMP is 1.6 wt.%.And the nl. 2.In the reaction products of harmful impurities, such as oxide of mesityl, (OHMS) and two-methylbenzofuran (2 IMF) was observed in only trace amounts.In the reaction products OHMS and MBF observed only in trace amounts.When considering the results of the decomposition of the technical code of civil procedure to the claimed method and compared with the results of the decomposition of the CCP according to the method of the prototype shows that:
1. The inventive method provides a safer and more selective process at stage 1 with residual contents of the CCP in the circulating PMP 0,14; 0.21 and 0.11 wt.%, (rated at not more than 0.3 wt.%) the resulting outputs of the MPC, respectively 66,4; 78.9% and 76.2% of capacity.According to the method of the prototype (5) when the content of the CCP in the circulating PMP, equal to 2.7% (rated at 0.5 to 5 wt.%), the output of MPC from potential was 57-62%.Another known method (6), taken into account does not lead to the results of the selectivity of the process in the first stage, but claims that it is necessary to conduct this process with the remaining contents of the CCP 0.5 to 5 wt.%;
2. The inventive method provides a more selective process during a short exposure time of the reaction products (selected from stage 1 of the process) at an elevated temperature, because viha into account (6), this output is respectively 83 and 82%.It should be noted that in these (5 and 6) how the decomposition is subjected to GPC with a large (12,16 - 12,8%) diluent-cumene, which already contributes to increase the selectivity of the process.Stated in the same way the content of cumene in the original CCP does not exceed 1 wt.%;
3.The inventive method provides a smaller output components comprising the phenolic resin (DMFC + ACF + MAC + DAS + CF).Thus, the output of these components (table. 2) in the calculation of the decomposed SBC in the claimed method was :
(0,12+0,52+0,08+0,35+0,18) : 0,9355 = 1,336
(0,11+0,45+0,1+0,32+0,15) : 0,9382 = 1,194
(0,1+0,43+0,1+0,33+0,16) : 0,9437 = 1,187
In the known methods [5, 6] these outputs are:
1,6 : 0,830 = 1,927
1,22 : 0,838 = 1,466
Thus, the objectives of the claimed method, is achieved. 1. The method of stepwise decomposition of gidroperekisi hydroperoxide (CHP) acid catalyst to phenol and acetone, conducted at mild conditions with the circulation of the reaction mass decomposition (PMP), characterized in that the source of the CCP is decomposed in the reactor system reverse blending to a residual content of her in the reaction products is not more than 0.3 wt.% by introducing sitebut depending on the temperature difference at the ends of the device control decomposition, where mixed part of PMP with the entire volume of acid catalyst, the decomposition process is carried out in the reactor with the vortex motion of the products of the reaction, and the stage of decomposition of residual dimethylphenylcarbinol and peroxide of Dicumyl in target products carried out with a stepwise decrease of the pH by entering the water in the apparatus structural flow.2. The method according to p. 1, characterized in that the acid catalyst is a solution of 0.3 - 0.5% sulfuric acid in acetone.3. The method according to p. 1, characterized in that the circulating PMP is introduced into the reactor inverse blending tangentially.4. The method according to p. 1, characterized in that the source of the CCP introduced in pricebuy zone of the reactor.5. The method according to p. 1, characterized in that the input of water in the apparatus structural flow is at a distance of 1/4 from the beginning of the length of the device.6. The method according to p. 1, characterized in that the amount of water introduced into the apparatus structural flow is 0.5 to 6.0% of the number of the reaction mass decomposition.
FIELD: petroleum chemical technology.
SUBSTANCE: invention relates to utilization of phenolic resin and preparing additional amounts of cumene, phenol and α-methylstyrene. For this aim phenolic resin containing less 0.2 wt.-% of salts is subjected for thermocatalytic decomposition in the range of temperatures 420-550oC in the presence of steam on catalyst comprising the following components, wt.-%: aluminum, oxide, 5.0-30.0; iron oxide, 0.4-1.0; magnesium oxide, 0.4-1.0; calcium oxide, 5.2-7.0; sodium oxide, 1.0-3.0; potassium oxide, 1.0-3.0; titanium (IV) oxide, 0.4-1.0; silicon (IV) oxide, 0.4-1.0, the balance, up to 100%. The proposed method provides preparing 61.5 wt.-% of useful products - cumene, phenol and α-methylstyrene for a single run. Invention can be used in the process for combined preparing phenol and acetone by cumene method.
EFFECT: improved preparing method.
2 cl, 3 tbl, 6 ex
FIELD: industrial organic synthesis.
SUBSTANCE: invention relates to production of phenol via acid catalytic decomposition of cumene hydroperoxide followed by isolation of phenol from decomposition products and purification of phenol to remove trace impurities including acetol. Purification of phenol is accomplished through hetero-azeotropic rectification with water. Acetol is isolated as a part of liquid-phase side stream from semiblind plate located within exhausting section of hetero-azeotropic rectification column. Side stream is supplemented by cumene and used to supply stripping column, from which fraction of acetol/cumene azeotropic mixture is taken as distillate and residue is returned under semiblind plate of hetero-azeotropic rectification column to be further exhausted. From the bottom of the latter, crude phenol is withdrawn and passed to final purification from the rest of reactive trace impurities. Acetol/cumene azeotropic mixture is subjected to heat treatment at 310-350°C, which may be performed in mixtures with high-boiling production waste or in mixtures with bottom product of rectification column for thermal degradation of high-boiling synthesis by-products, which bottom product is recycled via tubular furnace. Above-mentioned semiblind plate, from which side stream is tapped, is disposed in column zone, wherein content of water is minimal and below which contact devices are positioned with efficiency at least 7.5 theoretical plates. Side stream with cumene added to it is passed to the vat of stripping column with efficiency at least 15 theoretical plates.
EFFECT: minimized content of acetol in purified phenol and reduced power consumption.
5 cl, 3 dwg, 6 tbl, 4 ex