A system and method for recovering isononol residue

Abstract

This invention discloses an isononol residue recovery system, which recovers the useful components from the residue produced by the isononol unit, turning waste into treasure, reducing the amount of residue in the isononol unit, reducing its raw material consumption, and improving the economic efficiency of the isononol unit.

Description

Technical Field

[0001] This invention relates to the field of isononol preparation technology, and in particular to an isononol residue recovery system and recovery method. Background Technology

[0002] Isononol (INA) is primarily used in the production of high molecular weight phthalate plasticizers such as diisononyl phthalate (DINP). With increasing market acceptance of the safety of DINP, its demand is rapidly growing as an environmentally friendly alternative to low molecular weight phthalate plasticizers such as dioctyl phthalate (DOP), and it is widely used in industries such as automotive, cable, flooring, and construction.

[0003] Currently, my country has limited varieties of plasticizer alcohols, including only n-butanol, isobutanol, and octanol. Other plasticizer alcohols such as isononol, isodecanol, and 2-propylheptanol are produced in small quantities. Europe has completely banned the use of DOP, DBP, and BBP plasticizers in children's plastic toys, and the United States has also permanently banned the production and sale of children's products containing more than 0.1% DOP, DBP, and BBP by mass. Although the fate of DOP is still uncertain, the trend of DOP being replaced by other, better-performing plasticizers is irreversible. It is foreseeable that the future development prospects of DINP are optimistic. As the world's largest toy exporter, China has a promising DINP market and should accelerate the pace of plasticizer product structure adjustment.

[0004] Isononol is a raw material for the production of DINP. Currently, the preparation of isononol involves two main steps: the first step is the hydroformylation of octene to produce isononal, and the second step is the hydrogenation reduction of isononal to obtain isononol. After removing light and heavy components, the isononol product is obtained, with the residual liquid from this process accounting for approximately 5-15% of the isononol. This residual isononol contains more than 50% isononol and isononal, with the remainder mostly being a mixture of dimers and trimers of isononal. If the isononal and isononol can be recovered, the raw material consumption for isononol can be significantly reduced, improving the economic efficiency of the isononol plant.

[0005] Patent CN201911353572.7 discloses a method and system for co-producing isononol and C8 alkylene, but it does not consider the recovery and treatment of isononol residue. Patent CN201911220649.3 discloses a method for preparing isononol from mixed octene, which also does not consider the recovery and treatment of isononol residue. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing an isononol residue recovery system and method.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The first aspect of the present invention provides an isononol residue recovery system, comprising an isononol residue feed buffer tank, a hydrogenation feed pump, a hydrogenation feed preheater, a hydrogenation reactor, a gas-liquid separator, and a deweighting tower connected in sequence by pipelines; the bottom of the deweighting tower is connected to a deweighting tower reboiler, and the top of the deweighting tower is connected in sequence by pipelines to a condenser, a light component reflux tank, and a light component reflux pump.

[0009] A second aspect of the present invention provides a method for recovering isononol residue, employing the aforementioned isononol residue recovery system, comprising the following steps:

[0010] The isononol residue from the isononol unit enters the isononol residue feed buffer tank. After being pressurized by a pump, the isononol residue is sent to the hydrogenation feed preheater. After being preheated to the hydrogenation temperature, it enters the hydrogenation reactor along with hydrogen. The isononal in the isononol residue reacts with hydrogen to produce isononol. The resulting hydrogenation reaction liquid is sent to a gas-liquid separator. The top of the gas-liquid separator discharges vent gas, and the bottom material enters the de-heavy component tower. The light component at the top of the de-heavy component tower is condensed by the condenser and enters the light component reflux tank. Part of the liquid phase at the bottom of the light component reflux tank is sent back to the de-heavy component tower, and part is sent to the inlet of the hydrogenation reactor of the isononol main unit. The heavy component at the bottom of the de-heavy component tower is sent to the outside.

[0011] Furthermore, the isononol residue comes from the light and heavy removal tower of the isononol main unit.

[0012] Furthermore, the catalyst used in the hydrogenation reactor is a nickel-based, copper-based, or palladium-based supported hydrogenation catalyst.

[0013] Furthermore, the support for the supported hydrogenation catalyst is one or a combination of silicon oxide, aluminum oxide, and zirconium oxide.

[0014] Furthermore, the hydrogenation reactor is a trickle bed reactor.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] The residual liquid recovery system of the present invention is designed to recover useful components from the residual liquid produced by the isononol unit, turning waste into treasure, reducing the amount of residual liquid in the isononol unit, reducing its raw material consumption, and improving the economic efficiency of the isononol unit. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the isononol residual liquid recovery system of the present invention;

[0018] The reference numerals in the attached figures are:

[0019] 1-Isononol residual liquid feed buffer tank, 2-Hydrogenation feed pump, 3-Hydrogenation feed preheater, 4-Hydrogenation reactor, 5-De-heavy column, 6-Condenser, 7-Light component reflux tank, 8-Light component reflux pump, 9-De-heavy column reboiler. Detailed Implementation

[0020] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings to enable a better understanding of the invention. However, the following embodiments do not limit the scope of the invention.

[0021] refer to Figure 1 This invention discloses an isononol residue recovery system, comprising an isononol residue feed buffer tank 1, a hydrogenation feed pump 2, a hydrogenation feed preheater 3, a hydrogenation reactor 4, a gas-liquid separator 10, and a de-heavy component tower 5 connected in sequence by pipelines; a de-heavy component tower reboiler 9 is connected to the bottom of the de-heavy component tower 5, and a condenser 6, a light component reflux tank 7, and a light component reflux pump 8 are connected in sequence by pipelines to the top of the de-heavy component tower 5.

[0022] This invention also discloses a method for recovering isononol residue, which uses the above-mentioned isononol residue recovery system and includes the following steps:

[0023] The isononol residue from the isononol unit enters the isononol residue feed buffer tank 1. After being pressurized by pump 2, the isononol residue is sent to the hydrogenation feed preheater 3. After being preheated to the hydrogenation temperature, it enters the hydrogenation reactor 4 together with hydrogen. The isononal in the isononol residue reacts with hydrogen to produce isononol. The resulting hydrogenation reaction liquid is sent to the gas-liquid separator 10. The top of the gas-liquid separator 10 discharges vent gas, and the bottom material enters the de-heavy component tower 5. The light component at the top of the de-heavy component tower 5 is condensed by condenser 6 and then enters the light component reflux tank 7. Part of the liquid phase component at the bottom of the light component reflux tank 7 is sent back to the de-heavy component tower 5, and part is sent to the inlet of the hydrogenation reactor of the isononol main unit. The heavy component at the bottom of the de-heavy component tower 5 is sent to the outside.

[0024] In this invention, the aforementioned isononol residue comes from the light and heavy removal tower of the isononol main unit.

[0025] As a preferred embodiment of the present invention, the catalyst used in the hydrogenation reactor 4 is a nickel-based, copper-based or palladium-based supported hydrogenation catalyst, and the support for the supported hydrogenation catalyst is one or a combination of silicon oxide, alumina and zirconium oxide; the hydrogenation reactor 4 is a trickle bed reactor.

[0026] Example 1

[0027] 50 kg of isononol residue (2.37% water, 0.6% octene, 7.56% isononal, 53.13% isononol, 36.29% dinonal) from the isononol removal tower is pressurized to 25 kg by hydrogenation feed pump 2, preheated to 80 degrees Celsius, mixed with 1 kg of hydrogen, and then fed into hydrogenation reaction 4. The hydrogenation reactor is filled with a nickel-based hydrogenation catalyst. In hydrogenation reaction 4, octene is hydrogenated to octane, and isononol is hydrogenated to isononol. The resulting hydrogenated reaction liquid then enters a gas-liquid flash tank 10. The gas-liquid flash tank is subjected to adiabatic flashing at an operating pressure of 4 kg to remove unreacted hydrogen. The material at the bottom of the steam tank enters the deweighting tower 5. The operating pressure at the top of the deweighting tower is 15 kPaA, and the operating temperature at the bottom of the tower is 84 degrees Celsius. A condenser 6, a light component reflux tank 7, and a light component reflux pump 8 are installed at the top of the tower. 31.35 kg of vapor phase at the top of the tower enters the top condenser 6, of which 2.85 kg of condensate is pressurized by the light component reflux pump 8 and then refluxed. 28 kg of useful components (95.6% isononol, 3.34% water, and 0.78% octane) are collected from the light component reflux tank 7. The operating temperature at the bottom of the deweighting tower 5 is 183 degrees Celsius, and 21 kg of heavy components (14.3% isononol and 85.6% dinonanal) are discharged.

[0028] Comparative Example 1

[0029] In current industrial plants, the residual liquid of isononol is discharged directly without recovering the useful components.

[0030] Analysis of the residual liquid from the existing equipment shows that the total content of isononaldehyde and isononol exceeds 50%. Based on a recovery rate of 85% and an isononol unit with a capacity of 100,000 tons / year, with a residual liquid volume of 8,000 tons / year, 3,400 tons of isononol can be recovered annually. Assuming an isononol selling price of 8,000 yuan / ton, the estimated annual revenue is 27.2 million yuan.

[0031] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the content of the present invention specification and drawings should be included within the protection scope of the present invention.

Claims

1. A method for recovering isononyl alcohol raffinate, characterized by, An isononol residue recovery system is adopted, which includes an isononol residue feed buffer tank (1), a hydrogenation feed pump (2), a hydrogenation feed preheater (3), a hydrogenation reactor (4), a gas-liquid separator (10), and a de-heavy column (5) connected in sequence by pipelines; the bottom of the de-heavy column (5) is connected to a de-heavy column reboiler (9), and the top of the de-heavy column (5) is connected in sequence by pipelines to a condenser (6), a light component reflux tank (7), and a light component reflux pump (8); The method includes the following steps: The isononol residue from the isononol unit enters the isononol residue feed buffer tank (1). The isononol residue is pressurized by the hydrogenation feed pump (2) and sent to the hydrogenation feed preheater (3). After being preheated to the hydrogenation temperature, it enters the hydrogenation reactor (4) together with hydrogen. The isononal in the isononol residue reacts with hydrogen to generate isononol. The generated hydrogenation reaction liquid is sent to the gas-liquid separator (10). The gas-liquid separator (10) discharges the purge gas at the top and the bottom material enters the de-heavy tower (5). The light component at the top of the de-heavy tower (5) is condensed by the condenser (6) and enters the light component reflux tank (7). Part of the liquid phase component at the bottom of the light component reflux tank (7) is sent back to the de-heavy tower (5) and the other part is sent to the inlet of the hydrogenation reactor of the isononol unit. The heavy component at the bottom of the de-heavy tower (5) is sent to the outside. The isononol residue comes from the light and heavy removal tower of the isononol unit, and the isononol residue includes isononol, dinonanal, isononanal, water and octene.

2. The isononyl alcohol raffinate recovery process of claim 1, wherein, The catalyst used in the hydrogenation reactor (4) is a supported hydrogenation catalyst containing nickel, copper or palladium.

3. The isononyl alcohol raffinate recovery process of claim 2, wherein, The support for the supported hydrogenation catalyst is one or a combination of silicon oxide, aluminum oxide, and zirconium oxide.

4. The isononyl alcohol raffinate recovery process of claim 1 wherein, The hydrogenation reactor (4) is a trickle bed reactor.

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