Limonene extractant in tire pyrolysis oil and preparation method and application thereof

Abstract

The application discloses a limonene extraction agent in tire pyrolysis oil, wherein 30-60wt% p-aminoacetanilide and 40-70wt% quinoline are contained in the extraction agent; the extraction agent changes the interaction force between substances by itself group, and then changes the relative volatility between key components, so that the limonene product can reach more than 95% of industrial grade purity, and the yield of the limonene product also reaches more than 85%.

Description

Technical Field

[0001] This invention relates to the fields of petrochemical and fine chemical technology, and in particular to a limonene extractant for tire pyrolysis oil, its preparation method, and its application. Background Technology

[0002] Limonene, also known as limonene, has the chemical formula C60. 10 H 16 With a boiling point of approximately 176℃, limonene is a cycloalkane aliphatic compound. It has wide applications in solvent washing, organic synthesis, fragrances, pharmaceuticals, pesticide preparation, and other fields. Especially in industrial cleaning, limonene can be used as a cleaner for mechanical parts, wheels, and glass.

[0003] Currently, the sources of high-purity, high-value-added limonene are relatively limited. Industrial-grade limonene is mainly extracted from natural plants with relatively high limonene content (such as the peels of lemons and citrus fruits) using physical extraction methods. Because this natural limonene is produced in small quantities and has high added value, it is mostly used in pharmaceuticals and fragrances. However, the demand for limonene in the industrial cleaning sector is enormous. Using natural limonene products would be wasteful and costly; the best approach is to use industrial extraction or chemical synthesis methods.

[0004] Tire pyrolysis oil is the main product of tire pyrolysis, with a product yield of up to 45%. Chromatographic analysis revealed that the pyrolysis oil contains limonene, with a content of 3-6%. Moreover, the large output of tire pyrolysis oil can solve the problem of limited limonene sources and applications.

[0005] CN110938450A discloses a method for preparing pyrolysis oil by pressurizing and pyrolyzing waste tires, and further separating the pyrolysis oil to obtain 50% limonene. The method for obtaining limonene from tire pyrolysis oil in this patent is "fractional distillation", but the concentration of limonene obtained by this method does not meet the requirements of industrial limonene products.

[0006] Pakdel et al. obtained a limonene fraction of 92% by distillation and column chromatography, but this method is inefficient and has a large loss, and is not suitable for widespread application (PAKDEL H, PANTEA DM, ROY C. Production of dl-limonene by vacuum pyrolysis of used tires[J]. Journal of Analytical and Applied Pyrolysis, 2001, 57(1):91-107.).

[0007] Stanciulescu et al. converted limonene into limonene ethers of similar higher value through etherification, thereby widening the boiling point difference between the target substance and impurities, and then achieving separation through distillation. However, the selectivity of limonene ethers in the etherification reaction was only 25%, and the separation effect of distillation was unknown (STANCIULESCU M, IKURA M. Limonene ethers from tire pyrolysis oil. Part 1: Batch experiments[J]. Journal of Analytical and Applied Pyrolysis, 2006, 75(2): 217-225.;STANCIULESCU M, IKURA M. Limonene ethers from tire pyrolysis oil. Part 2: Continuous flow experiments[J]. Journal of Analytical and Applied Pyrolysis, 2007, 78(1): 76-84.).

[0008] Therefore, there is an urgent need to develop a suitable method for extracting high concentrations of limonene from tire pyrolysis oil. Summary of the Invention

[0009] The inventors discovered in their distillation experiments to extract limonene that, in the distillation range of tire pyrolysis oil, which has a boiling point close to limonene's 176°C, other organic compounds with similar boiling points to limonene are also present, such as para-cymene (boiling point approximately 177°C), thiobenzene (boiling point approximately 176°C), and indene (boiling point approximately 177°C). These compounds have similar boiling points, similar polarities, and similar relative volatility, making it difficult to effectively separate them using conventional distillation methods, thus failing to obtain industrial-grade limonene products with a content ≥95%.

[0010] To solve the above problems, the inventors tried to separate and extract limonene using extractive distillation.

[0011] Extractive distillation involves adding another high-boiling-point component, the extractant, to an azeotrope. The extractant does not form an azeotrope with either of the components and alters their relative volatility, thus achieving separation of the system. The extractive distillation process is simple: after adding the third component, distillation is performed, and the lighter components are distilled off at the top of the column. After the lighter components have been distilled off, the extractant and heavier components remain in the bottom of the column. Because the extractant and heavier components do not form an azeotrope and have a significant difference in boiling points, they are easily separated using conventional distillation methods, and the extractant can be recycled.

[0012] The key to extractive distillation is to select or screen a suitable extractant to ensure that the entire extractive distillation process has low energy consumption, a simple process, and good product quality.

[0013] Therefore, the present invention provides a limonene extractant for tire pyrolysis oil, characterized in that the extractant comprises 30-60 wt% p-aminoacetanilide and 40-70 wt% quinoline.

[0014] Furthermore, the extractant comprises 40-50 wt% p-aminoacetanilide and 50-60 wt% quinoline.

[0015] Furthermore, the extractant comprises 40 wt% p-aminoacetanilide and 60 wt% quinoline.

[0016] After atmospheric or vacuum distillation, the main components of tire pyrolysis oil are umbelliferous hydrocarbons, limonene, and trimethylbenzene. After adding the extractant of this invention, the self-groups in the extractant change the interaction forces between umbelliferous hydrocarbons, limonene, and trimethylbenzene, thereby changing the relative volatility of the three components and separating the three organic compounds with similar boiling points.

[0017] This invention provides a method for preparing a limonene extractant, which involves mixing p-aminoacetanilide with quinoline to obtain a limonene extractant for tire pyrolysis oil.

[0018] Furthermore, the preparation route of the p-aminoacetanilide is as follows:

[0019]

[0020] That is, acetaminophen is used as a raw material and reacted with phosphorus oxychloride to obtain a chlorinated intermediate product. The chlorinated intermediate product is then mixed with an ammonia solution to obtain an ammonolytic compound (p-aminoacetanilide).

[0021] The present invention also provides a method for extracting limonene from tire pyrolysis oil, the method comprising: extracting limonene from tire pyrolysis oil using the above-mentioned extractant.

[0022] Furthermore, the ratio of extractant to tire pyrolysis oil is 4 to 10:1.

[0023] Furthermore, the ratio of extractant to tire pyrolysis oil is 4–6:1.

[0024] Furthermore, the ratio of extractant to tire pyrolysis oil is 6:1.

[0025] In this invention, limonene is enriched before the extraction of tire pyrolysis oil.

[0026] Furthermore, the enrichment process is vacuum distillation.

[0027] Furthermore, after the enrichment treatment, the limonene content is 50-70%; even further, the limonene content is 60%.

[0028] In some specific embodiments of the present invention, light components are removed prior to enrichment treatment; said light components include dienes.

[0029] In some specific embodiments of the present invention, the extraction method of limonene from tire pyrolysis oil includes the following steps:

[0030] (1) Perform atmospheric distillation on tire pyrolysis oil;

[0031] (2) The tire pyrolysis oil obtained in step (1) is subjected to vacuum distillation. The vacuum distillation uses a vacuum plate column and a side-stream column. The limonene-enriched component is collected from the bottom of the side-stream column.

[0032] (3) The limonene enriched component from the bottom of the side stream column and the extractant enter the extractive distillation column. The extractive distillation column is a plate column. The mass ratio of the extractant to the limonene enriched component is (4-10):1. Industrial-grade limonene is collected from the top of the extractive distillation column, and the bottom of the column is the extractant-rich liquid.

[0033] (4) The extractant rich solution is regenerated in the regeneration tower, which is a plate tower.

[0034] In this invention, atmospheric distillation uses a plate column to evaporate light components rich in dienes, preventing high-temperature coking of the pyrolysis oil in subsequent processing.

[0035] The beneficial effects of this invention are:

[0036] The limonene extractant provided by this invention is mainly composed of ammonolytic compounds synthesized from acetaminophen and their quinoline mixtures. It extracts and separates limonene, p-cymene, and tertoluene in tire pyrolysis oil with similar volatility and boiling point. The extractant changes the interaction forces between substances by altering its own functional groups, thereby changing the relative volatility between key components. This allows the limonene product to achieve an industrial-grade purity of over 95%, and the yield of the limonene product also reaches over 85%. Attached Figure Description

[0037] Figure 1 Spectrum A of tire pyrolysis oil;

[0038] Figure 2 Spectrum B of tire pyrolysis oil;

[0039] Figure 3 Spectrum C of tire pyrolysis oil;

[0040] Figure 4Spectrum D of tire pyrolysis oil;

[0041] Figure 5 Spectrum analysis of limonene fraction after vacuum enrichment of tire pyrolysis oil ( Figures 1-5 In Chinese: 1-Benzene; 2-Toluene; 3-Ethylbenzene; 4-o-xylene; 5-Styrene; 6-m-xylene; 7-3-Ethyltoluene; 8-4-Ethyltoluene; 9-1,3,5-Trimethylbenzene; 10-1,2,4-Trimethylbenzene; 11-1,2,3-Trimethylbenzene; 12-p-Cymene; 13-Limonene; 14-P-Cymene enriched under reduced pressure; 15-Limonene enriched under reduced pressure; 16-Trimethylbenzene enriched under reduced pressure). Detailed Implementation

[0042] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Example 1: Preparation of limonene extractant

[0044] A method for preparing limonene extractant from tire pyrolysis oil includes the following steps:

[0045] (1) Using acetaminophen as a raw material, it reacts with phosphorus oxychloride to obtain p-chloroacetanilide;

[0046] (2) p-Chloroacetanilide is mixed with an ammonia solution to obtain an ammonolytic compound (p-aminoacetanilide);

[0047] (3) The ammonolytic compound (aminoacetanilide) is mixed with quinoline and stirred thoroughly to obtain the desired tire pyrolysis oil limonene extractant product.

[0048] Example 2

[0049] Limonene extractant was prepared using the method described in Example 1. In the limonene extractant, ammonolytic compounds accounted for 40% by mass, and quinoline accounted for 60% by mass. The tire pyrolysis oil used contained approximately 6 wt% limonene, with an initial boiling point of 70°C and a final boiling point of 390°C.

[0050] Limonene extractant is extracted through the following steps:

[0051] (1) The pyrolysis oil is distilled under atmospheric pressure. The atmospheric distillation is carried out using a plate column with 20 plates.

[0052] (2) The pyrolysis oil after atmospheric distillation is subjected to vacuum distillation using a vacuum plate column with 55 trays. A side-stream feed line is set at the 15th tray, and a side-stream column is set downstream of the feed line. The side-stream column has 5 trays. The limonene-enriched fraction is collected from the bottom of the side-stream column. The limonene content in the enriched fraction is approximately 60%, with the remainder being p-cymenes and tertoluene, etc. Figure 5 As shown, the limonene-enriched components after decompression enrichment mainly contain p-cymene, limonene, and trimethylbenzene, with limonene having the highest content.

[0053] (3) The limonene enriched component from the bottom of the side-stream distillation column, along with the extractant, enters an extractive distillation column. The extractive distillation column is a plate column with 60 plates, and the mass ratio of extractant to limonene enriched component is 6:1. Industrial-grade limonene product with a purity of 96% is collected from the top of the extractive distillation column. The bottom of the column contains a rich extractant solution, mainly consisting of extractant, p-cymene, and tertoluene.

[0054] (4) The rich extractant solution is regenerated in the regeneration tower to realize the recycling of the extractant; the regeneration tower is a plate tower with 15 plates, thus realizing the recycling of the extractant.

[0055] In this embodiment, the recovery rate of the extractant was 99.6%, the extraction rate of limonene in tire pyrolysis oil was 89.5%, and the energy consumption per unit of limonene product was converted to standard oil at 450 kg standard oil / t limonene.

[0056] Example 3

[0057] Limonene extractant was prepared using the method described in Example 1. In the limonene extractant, ammonolytic compounds and quinoline comprised 50% by mass. The tire pyrolysis oil used contained approximately 6 wt% limonene, with an initial boiling point of 70°C and a final boiling point of 390°C.

[0058] The extraction method in this embodiment is the same as in Example 2. The purity of the limonene product obtained is 95.2%; the recovery rate of the extractant is 99.1%; the extraction rate of limonene in tire pyrolysis oil is 88.8%; and the energy consumption per unit of limonene product is equivalent to 475 kg of standard oil / t of limonene.

[0059] Example 4

[0060] Limonene extractant was prepared using the method described in Example 1. In the limonene extractant, ammonolytic compounds accounted for 40% by mass, and quinoline accounted for 60% by mass. The tire pyrolysis oil used contained approximately 6 wt% limonene, with an initial boiling point of 70°C and a final boiling point of 390°C.

[0061] The extraction steps in this embodiment are the same as those in Example 2, except for step (3). As follows:

[0062] (1) The pyrolysis oil is distilled under atmospheric pressure. The atmospheric distillation is carried out using a plate column with 20 plates.

[0063] (2) The pyrolysis oil after atmospheric distillation is subjected to vacuum distillation using a vacuum plate column with 55 trays. A side-stream feed line is set at the 15th tray, and a side-stream column is set downstream of the feed line. The side-stream column has 5 trays. The bottom of the side-stream column yields a limonene-enriched fraction, which contains approximately 60% limonene, with the remainder being p-cymene and tertoluene, etc.

[0064] (3) The limonene enriched component from the bottom of the side-stream distillation column, along with the extractant, enters an extractive distillation column. The extractive distillation column is a plate column with 60 plates, and the mass ratio of extractant to limonene enriched component is 4:1. Industrial-grade limonene product with a purity of 92% is collected from the top of the extractive distillation column.

[0065] (4) The rich extractant solution is regenerated in the regeneration tower to realize the recycling of the extractant; the regeneration tower is a plate tower with 15 plates, thus realizing the recycling of the extractant.

[0066] In this embodiment, the recovery rate of the extractant was 99.7%. The extraction rate of limonene from tire pyrolysis oil was 87.6%, and the energy consumption per unit of limonene product was 470 kg of standard oil / t of limonene.

[0067] Example 5

[0068] Limonene extractant was prepared using the method described in Example 1. In the limonene extractant, ammonolytic compounds and quinoline comprised 50% by mass. The tire pyrolysis oil used contained approximately 6 wt% limonene, with an initial boiling point of 70°C and a final boiling point of 390°C.

[0069] In this embodiment, the extraction method is the same as in Example 2, except for step (3), all other steps are the same, as follows:

[0070] (1) The pyrolysis oil is distilled under atmospheric pressure. The atmospheric distillation is carried out using a plate column with 20 plates.

[0071] (2) The pyrolysis oil after atmospheric distillation is subjected to vacuum distillation using a vacuum plate column with 55 trays. A side-stream feed line is set at the 15th tray, and a side-stream column is set downstream of the feed line. The side-stream column has 5 trays. The bottom of the side-stream column yields a limonene-enriched fraction, which contains approximately 60% limonene, with the remainder being p-cymene and tertoluene, etc.

[0072] (3) The limonene enriched component from the bottom of the side-stream distillation column, along with the extractant, enters an extractive distillation column. The extractive distillation column is a plate column with 60 plates, and the mass ratio of extractant to limonene enriched component is 8:1. Industrial-grade limonene product with a purity of 91% is collected from the top of the extractive distillation column.

[0073] (4) The rich extractant solution is regenerated in the regeneration tower to realize the recycling of the extractant; the regeneration tower is a plate tower with 15 plates, thus realizing the recycling of the extractant.

[0074] In this comparative example, the recovery rate of the extractant was 99.4%, the extraction rate of limonene in tire pyrolysis oil was 88.6%, and the energy consumption per unit of limonene product was converted to standard oil at 490 kg standard oil / t limonene.

[0075] Example 6

[0076] Limonene extractant was prepared using the method described in Example 1. In the limonene extractant, ammonolytic compounds accounted for 40% by mass, and quinoline accounted for 60% by mass. The tire pyrolysis oil used contained approximately 5 wt% limonene, with an initial boiling point of 120°C and a final boiling point of 550°C. Compared to Examples 2-5, this example used a heavier pyrolysis oil with a lower effective limonene content.

[0077] The extraction steps in this embodiment are the same as in Example 2, and the purity of the obtained limonene product is 96%; the recovery rate of the extractant is 99.1%. The extraction rate of limonene in tire pyrolysis oil is 87.5%, and the energy consumption per unit of limonene product is equivalent to 520 kg of standard oil / t of limonene.

[0078] Comparative Example 1

[0079] Limonene extractant was prepared using the method described in Example 1. In the limonene extractant, ammonolytic compounds accounted for 40% by mass, and quinoline accounted for 60% by mass. The tire pyrolysis oil used contained approximately 6 wt% limonene, with an initial boiling point of 70°C and a final boiling point of 390°C.

[0080] The extraction steps in this embodiment are the same as in Example 2, except that step (2) is omitted and the mass ratio of the extractant to the pyrolysis oil is changed. The steps are as follows:

[0081] (1) The pyrolysis oil is distilled under atmospheric pressure. The atmospheric distillation is carried out using a plate column with 20 plates.

[0082] (2) The pyrolysis oil after atmospheric distillation and the extractant are fed into the extractive distillation column. The extractive distillation column is a plate column with 60 plates. The mass ratio of extractant to pyrolysis oil is 1:1. The purity of limonene at the top of the extractive distillation column is about 70%, which does not meet the requirements of industrial-grade limonene products.

[0083] (3) The rich extractant solution is regenerated in the regeneration tower to realize the recycling of the extractant; the regeneration tower is a plate tower with 15 plates, thus realizing the recycling of the extractant.

[0084] The results obtained from Examples 1 to 6 and Comparative Example 1 are shown in Table 1:

[0085] Table 1

[0086]

[0087]

[0088] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An extractant for limonene in tire pyrolysis oil, characterized in that, The extractant contains 30-60 wt% p-ammonia Acetanilide and 40-70 wt% quinoline.

2. The extractant according to claim 1, characterized in that, The extractant comprises 40-50 wt% p-aminoacetanilide and 50-60 wt% quinoline.

3. The extractant according to claim 1, characterized in that, The extractant comprises 40 wt% p-aminoacetanilide and 60 wt% quinoline.

4. A method for extracting limonene from tire pyrolysis oil, characterized in that, The extraction method includes: extracting limonene from tire pyrolysis oil using the extractant described in any one of claims 1-3.

5. The extraction method according to claim 4, characterized in that, The ratio of the extractant to tire pyrolysis oil is 4~10:

1.

6. The extraction method according to claim 4, wherein the ratio of the extractant to the tire pyrolysis oil is 4 to 6:

1.

7. The extraction method according to claim 4, characterized in that, The ratio of the extractant to tire pyrolysis oil is 6:

1.

8. The extraction method according to claim 4, characterized in that, Limonene was enriched before the extraction of tire pyrolysis oil.

9. The extraction method according to claim 8, characterized in that, The enrichment process is vacuum distillation.

10. The extraction method according to claim 8, characterized in that, After the enrichment treatment, the limonene content is 50-70%.

11. The extraction method according to claim 8, characterized in that, After the enrichment treatment, the limonene content was 60%.

12. The extraction method according to claim 8, characterized in that, Light components are removed before enrichment treatment.

13. The extraction method according to claim 12, characterized in that, The light component includes a diene.

14. A method for preparing the extractant according to any one of claims 1-3, characterized in that, A mixture of p-aminoacetanilide and quinoline was used to obtain an extractant for limonene in tire pyrolysis oil.

15. The preparation method according to claim 14, characterized in that, The preparation route of p-aminoacetanilide is as follows:

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