TWI243800B - Method for integrating waste sulfuric acid regeneration and alkylation process - Google Patents

Abstract

This invention is related to one kind of method for integrating the waste sulfuric acid regeneration and the alkylation process which includes the use of the waste sulfuric acid mixture produced from hydrogen peroxide and the alkylation process. Utilize the Fe2+ contained in the waste sulfuric acid to enhance the oxidizing power of hydrogen peroxide, which oxidizes the organic substances contained in the waste sulfuric acid to carbon dioxide and water, and then introduce NO2/SO3 gas to carry on the absorption procedure, by which sulfuric acid and nitric acid can be produced simultaneously and the concentration of the waste sulfuric acid can be relatively increased to the concentration suitable for alkylation reaction. And the regenerated sulfuric acid can flow into the alkylation process again to obtain the alkylation oil with high octane value.

Description

1243800

V. Description of the invention u) The technical field to which the invention belongs is a method for integrating waste sulfuric acid regeneration and alkylation process, in particular to improve the efficiency of alkylation process by effectively controlling the concentration of sulfuric acid. The octane number of Tienheng chemical oil can be obtained by the same% as the nitric acid by-product and reduce the regeneration of waste sulfuric acid. Prior art

In the petrochemical refining industry, the alkylation sintering obtained from the alkylation oil and the c3_5 olefin are calcined; the obtained calcination two: the branched sintered sintered calcined value of 92_97 is used, and it has both low volatility and: Fine hydrocarbons and aromatic hydrocarbons are excellent compositions of gasoline. The content of hydrocarbons may be limited. Therefore, the role of the incineration process in the future refining should be important. The proportion of alkylation due to gasoline will gradually increase to the current commercial species. The production of 50% alkylated oil using the hydrofluoric acid method < gas is heavy, so it is foggy and surrounds the surface problem. Therefore, the system is based on hydrofluoric acid. However, in the case of sulfuric acid boiling, sulfuric acid will be easily derivatized with a large amount of waste acid by performing the alkane method with sulfuric acid.

—Yi Kuang, you have been using the hydrofluoric acid method and the sulfuric acid method for more than 50 years, and have occupied about so far. But * because the hydrofluoric acid has a low boiling point (i 9 · 4 begging) and compared to:% if there is hydrofluoric acid When the acid escapes, the factory that will not easily dissipate with the water surface for a long time and will generate significant industrial safety for the firing reaction needs to establish a complete point (29t) higher than hydrofluoric acid, so if it occurs on the ground, Will form a mist, easier to handle = should be another option for the alkylation process. However, sulfur II caused subsequent processing problems. ’丨 L For the method of regenerating waste sulfuric acid, I would like to describe in detail

1243800 V. Description of the invention (2) Below ~ ~ ~ (1) SARP method · By the reaction of propylene and sulfuric acid to form ☆ alkane to extract and recover, which can reduce the process: phosphonium salt, the temperature of isobutyl is about 50 ° F, but The disadvantage of this method is still residual ::: Shaw consumption, operation and waste sulfuric acid to be treated. Acid-soluble oil of thoron concentration (2) Crystallization recovery method: by the temperature of liquid isobutyl hydrazone solution, the sulfuric acid molecules can be dissolved and separated by containing too much dagger, and the derived dilute sulfuric acid solution is beneficial = The body precipitates, and the easy body reacts to increase the sulfuric acid concentration. Introduction of sulfur trioxide gas (3) Vacuum stripping method: The nitric acid mixture contained in the waste sulfuric acid is subjected to an oxidation reaction to form compounds and substances, and is separated by a vacuum distillation unit. The compound in the knife is free of organic compounds or liquid dioxide to break organic matter ::: The operating rate can reach more than 85%, but the operation method is more stringent. The use of external voltage or current for organic matter directly generates carbon dioxide and Water, water molecules continue to electricity and oxygen 'by adjusting the electrolysis time and operating different concentrations of sulfuric acid. a (6), 2ϊ: Mixing hydrogen sulfide and waste sulfuric acid for high oxygen over 1 000 ° c: starvation;;: sulfur: = cooling, drying and other processes, using sulfuric acid for absorption :: give; turn into trioxide Sulfur 'uses the low concentration two ...' sequence to increase the sulfuric acid concentration. The regeneration of waste sulfuric acid in the commercial alkylation process is incineration. Page 6 1243800 V. Description of the invention (3)

The method only requires the waste rock to be treated to be free of dangerous acids, only R / Chenduma 88 ~ 90wt%, and used for dumplings; 5 Yongzhi sulfuric acid concentration needs to be 90-98wt%, @ μ ^ heart regeneration, ... The use of the sulfuric acid # car: low: Chen degrees of waste sulfuric acid for the incineration of the use of Linuo S 夂, but the value of alkylated oil. 〖Shuanghanyaozhong / Wu used the incineration method to make Ma Shiliu Brew_ $ a.,. M #The system used for regeneration is quite expensive. Α Therefore, commercial clothing must reach 100 to 150 tons / Japan's economy scale, which limits the scale of alkane chemical plant construction. Based on the inconvenience of waste sulfuric acid treatment and alkylation process at the current stage and the inventor's extensive research on the petroleum refinery's firing process, such as γ, γ, γ, γ, and γ, the present invention has been completed. Objects of the Invention Objects of the Invention It is to provide a method for the integration of waste sulfuric acid regeneration and alkylation process, and to improve the efficiency of the alkylation process by effectively controlling the acid concentration. The value of the burned oil is improved. The method of the present invention is due to the integration of the waste sulfuric acid regeneration method. It can supplement the sulfuric acid lost by alkane and obtain nitric acid products. It not only solves the problem of environmentally friendly waste sulphuric acid, but also reduces the cost of waste sulphuric acid regeneration. Detailed description of the invention The invention relates to a method for integrating waste sulphuric acid regeneration and alkylation process, including the use of The hydrogen oxide is mixed with the waste sulfuric acid produced in the alkylation process. The Fe2 + contained in the waste sulfuric acid is used to enhance the oxidizing power of the hydrogen peroxide. The organic matter contained in the waste sulfuric acid is oxidized to carbon dioxide and water, and then introduced into No. 2 / S. 〇3 gas, carry out the absorption process, can produce sulfuric acid and nitric acid at the same time and relatively increase the concentration of waste sulfuric acid to a concentration suitable for alkylation reaction, after regeneration Sulfuric acid reflux again

Page 7 1243800 V. Description of the invention

In the alkylation process, a high octane alkylated oil is obtained. In the Maoming method, the overconcentration for oxidizing the organic matter in the waste sulfuric acid may be 3 to 70% by weight, preferably 6 to 50% by weight. The oxidation reaction is performed at a low temperature of ^ 10 atm and a temperature of 0-120 ° C. 1. In the method of the present invention, NO? And SO3 used in the absorption program can be directly used NO? And SO3 gas, or M% and Η respectively. N 02 and S 03 obtained by gas oxidation. The gas concentrations of N 02 and S 03 can be 3-30 mole%, respectively. The concentration of hydrogen oxide solution and the use of No. 2 / S03 gas can determine the degree of regeneration of sulfur dioxide. Therefore, the concentration of sulfuric acid can be controlled by controlling the concentration of the hydrogen peroxide solution and the use of No. S03 gas. It is between 90-98% by weight suitable for the alkylation reaction, and an alkylated oil with a higher octane number can be obtained. In the method of the present invention, the conditions of the alkylation process are known to the petrochemical refining industry, but generally in the 90- 98 wt% concentration, more preferably 9 3 to 95 wt% concentration of sulfuric acid, is performed at a pressure of 50-70 psig and an operating temperature of 5-10. In the method of the present invention, Ch olefin means 3 to 5 carbons. Atomic straight or branched dilute hydrocarbons.

According to the method for regenerating waste sulfuric acid and integrating the alkylation process according to the present invention, it is possible to increase the concentration of the waste sulfuric acid and make up for the sulfuric acid lost in the alkaline washing process during the alkali washing process by passing in the absorption process of SO3. The mother must add new sulfuric acid 'can still achieve an efficient alkylation reaction. According to the method for regenerating waste sulfuric acid and integrating the alkylation process according to the present invention, not only the problem of waste sulfuric acid in the alkylation process can be solved, but also nitric acid can be by-produced and the efficiency of the alkylation process can be improved. Examples

1243800 V. Description of the invention (5) The present invention will be described in more detail with reference to the preferred embodiments and the illustrations. The first figure is a flowchart of the method for integrating the waste sulfuric acid regeneration and alkylation process of the present invention. First, an isobutane / c3_5 alkene alkylation reaction is performed in a calcination reactor (react OR) 10 in the presence of sulfuric acid at a temperature of 5-10 ° C and a pressure of 50-70 psig, wherein the sulfuric acid concentration is 93 -9 5wt%. The sulfuric acid and hydrocarbons produced by the alkylation reaction are separated in an acid retention tank (acidse 111 er) 60, where the sulfuric acid is refluxed from the acid retention tank 6 0 to the reactor i 0, and part of the sulfuric acid is returned from the acid retention tank 6 0 Oxidation reactor entering the waste sulfuric acid regeneration program 12 ° Hydrogen peroxide solution is introduced into the oxidation reactor 12 through the pipeline and mixed with sulfuric acid contained therein, and the organic matter contained in the sulfuric acid is oxidized to carbon dioxide and water. Carbon dioxide escapes in a gaseous form, at which time the sulfuric acid concentration is about 92-94 wt%. The concentration of the hydrogen peroxide solution is about 30% by weight, and the oxidation reaction is preferably performed at a temperature of 0 to 120 ° C and a pressure lower than 10 atm. The reaction time depends on the reaction conditions. It is about 0.5 hours in this example, and the organic matter removal rate can reach 90% or more. The sulfuric acid after the oxidation reaction enters the absorber 14 through the pipeline, and the N02 / S03 gas is introduced to perform the absorption process. After the absorption process, the sulfuric acid concentration increased by about 4% by weight. Simultaneously generate nitric acid; use a distillation tower 16 to separate nitric acid and regenerated sulfuric acid; the regenerated sulfuric acid then enters an acid wash 20 via a pipeline to extract the esters contained in the hydrocarbon, including alkanoic acid Ester (Alkyl sulfate) and dialkyl sulfate (Dialkyl sulfate), etc., recover some of the organic phase

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V. Description of the invention (6) Sulfate; the regenerated sulfuric acid meets with the sulfuric acid previously refluxed to the calcination reactor i 0 via a pipeline and enters the alkylation reactor 1 0 together. The process of separating nitric acid and regenerating sulfuric acid in the di sti 1 lation tower 16 mainly uses the boiling point of nitric acid being 86 and the sulfuric acid budding point being 290 ° C. The distillation is used in general applications. Separation operation in the tower 'This type of crane tower is also commonly used in the waste acid recovery process of the nitrobenzene nitrification process. In addition, the separated nitric acid solution can be used in the process of toluene nitration.

Using the method proposed by the present invention, the waste sulfuric acid produced by the calcination reaction is regenerated, so that the removal rate of organic matter can reach more than 90%, and then the oxidation reaction and the controlled introduction of N02 / S03 gas are absorbed in the absorption tower 14 for absorption. After the regeneration process such as the program, the sulfuric acid concentration can be increased by about 4% by weight to reach a concentration between 90-98% by weight suitable for the alkylation reaction, and preferably a concentration of 93-95% by weight. Can obtain higher octane number of alkylated oil. The hydrocarbon separated from the acid retention tank 60 enters the depressurization tank (f 1 ash drum) 62, and the c3 and C4 + hydrocarbons are separated. The C3 hydrocarbons are passed through a refrigerator 66 and a caustic After separation of wash 64 and depropanizer 68, propane can be obtained. The product at the bottom of the propane-removing column 68 is refluxed to the decompression tank 62; the C4 + hydrocarbons are removed from the residual sulfate and sulfuric acid in the hydrocarbons through the pickling tank 20 and the inspection tank 30, and then deisobutane is removed by A deisobutanizer 40 separates isobutane, and then passes through a debutanizer 50 to separate alkylated oil and butane. Example one

From the acid retention tank 60 to the reflux

Page 10 1243800

Reactor 1 ο, part of the sulfuric acid enters the waste sulfuric acid oxidation reactor 12 (oxidation reactor) 12 from the acid retention tank 60, at this time, the concentration of the waste sulfuric acid in the oxidation reactor 12 is 88% of the village, after: introduction Oxidation reactor 12 The organic matters in the sulfuric acid are carbon dioxide and carbon dioxide. The carbon dioxide escapes in gaseous form. At this time, the sulfuric acid concentration is diluted by about M%, and its volume expansion is 1.23 times. 〇3 The absorption process was performed on absorption 14 and the sulfuric acid concentration was increased to 94.5wt%. The volume expansion of sulfuric acid was 1.59 times. Therefore, after the waste sulfuric acid was regenerated, its volume was 1 · 9 6 At the same time, by-products of distillate 16 are separated by distillation of osmium nitric acid. Taguchi ’s example of the use of the above-mentioned regenerated sulfuric acid includes the following: the original volume of sulfuric acid in the sulfuric acid enters the pickling tank 20 to extract the sulfuric acid (A 1 ky 1 su 1 fate) and disulfuric acid produced by the calcination reaction. Dialkyl sulfate; 10% of the original waste acid volume of sulfuric acid enters the alkaline washing tank 64 to provide the free acid required for neutralization of the C3 stream acid-base; sulfuric acid of 60% of the original volume of waste acid Enter alkaline washing tank 30 to provide free acid (Freeacid), remaining Alkyl sulfate and sulfuric acid di; required for c4 + stream acidity test; Dialkyl sulfate (alkylation reaction above) The amount of free acid, Alkyl sulfate and Dialkyl sulfate contained in the alkylation product produced is based on the impurities contained in the feed of the alkylation process, such as Water content, oxides and diolefins, etc., during reaction

Page 11 1243800 V. Description of the invention (8) The space flow rate of hydrocarbon feed, the ratio of olefin / isobutane, and the degree of reaction mixing, etc., will also affect the amount of lye used, in other words, the formation The consumption of sparse acid in the alkylation process, and the sulfuric acid lost during the inspection and washing process in the alkylation process, can be regenerated and promoted by the controlled introduction of n02 / SO3 gas in the absorption tower in the absorption process of the present invention. The concentration of sulfuric acid makes up for the efficient alkylation reaction without the need to add new sulfuric acid, so as to obtain a high octane alkylated oil. The above examples of the present invention are only used to illustrate the preferred implementation modes of the present invention, rather than to limit the scope of the compounds of the present invention.

To sum up, the present invention not only can simply treat waste sulfuric acid and simultaneously produce nitric acid by integrating waste sulfuric acid regeneration and alkylation processes, but also can reduce the cost of lightening and increase the profit. And it has deep industrial use value.

1243800 Brief description of the diagram The first diagram is the flow chart of the integration method of the waste sulfuric acid regeneration and alkylation process of the present invention. Brief description of drawing number 10 Alkylation reactor 12 Oxidation reactor 14 Absorption column 16 Distillation column 2 0 Pickling tank 3 0 Inspection tank search 40 Deisobutane column 50 Debutane column 60 Acid retention tank 6 2 Decompression tank 6 4 Washing tank 66 Freezer 6 8 Go to propylene burning tower _

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Claims (1)

1243800 Patent application scope —A method of integrating waste sulfuric acid regeneration and alkylation process, a. Using hydrogen peroxide and alkyl to produce waste sulfuric acid produced in 4 ports & female 1, clothing, mixed in an oxidation reactor; flat 1i b, Utilize $ ρ 2 τ ^ 3 pe2 + contained in waste sulfuric acid to enhance the oxidizing power of hydrogen peroxide, and oxidize the organic matter contained in the waste stone to carbon dioxide and water; ^ = receiving tower, 'into the waste after oxidation reaction Sulfuric acid and NO 2 / S 0 3 gas controlled by V and 1 undergo absorption procedures, which can simultaneously generate osmic acid t nitric acid and relatively increase the concentration of waste sulfuric acid to a concentration suitable for the alkylation reaction; d · f into Luohe Tower 'Separate sulfuric acid and nitric acid with different boiling points, and separate the regenerated sulfuric acid into the alkylation process to obtain a high octane alkylated oil through the calcination reaction. 2. If the method of item i of the patent scope, The concentration of hydrogen peroxide used to oxidize organic matter in waste sulfuric acid can be 3-70 wt%. 3 · As stated in the second item of the patent scope>, the concentration of hydrogen peroxide used to oxidize organic matter in waste sulfuric acid can be 6 -50wt%. 4 · If you apply for a patent scope item 丨Method, in which NO 2 and S 0 3 used in the absorption procedure are directly used NO 2 & S 0 3 gas. 5. The method according to item 丨 of the scope of patent application, wherein NO and SO 3 used in the absorption procedure are separately NS 03 obtained by oxidation of Guan 3 and Η ′ gas. 6 • As stated in the method of item 4 or 5 of the patent scope, the concentration of No 2 and § 03 gas can be 3-30 mole%, respectively. 7 The method according to item 丨 of the patent application, wherein the alkylation process is isobutane Page 14 1243800 6. The scope of patent application and the chemical reaction of Ci3 „5 olefins. 8. For the method of the scope of patent application item 7, wherein the alkylation process is in the presence of sulfuric acid at a concentration of 90 to 98% by weight, at 5 The pressure is 0-70 psig and the operating temperature is 5-10 ° C. 9. If the method of the scope of the patent application is No. 8, the sulfuric acid concentration is 93-95wt% 〇1 0. The method wherein the organic matter contained in the waste sulfuric acid is an ester contained in a hydrocarbon. Page 15