Adsorption and purification device for cationic etherifying agent

Abstract

The utility model relates to the technical field of cationic etherifying agent production, in particular to an adsorption and purification device for a cationic etherifying agent, which comprises at least two resin adsorption towers, and the resin adsorption towers are connected end to end through a circulating pipeline to form a closed loop; the top of each resin adsorption tower is respectively communicated with a low-pressure steam main pipe, a compressed air main pipe and a cationic etherifying agent pure product discharging pipe, and the bottom of each resin adsorption tower is respectively communicated with a cationic etherifying agent feeding main pipe and a cationic etherifying agent crude product discharging pipe; a control valve is arranged on the circulating pipeline between every two adjacent resin adsorption towers; and the cationic etherifying agent crude product discharging pipe is communicated with the cationic etherifying agent feeding main pipe. According to the utility model, the multistage purification of the cationic etherifying agent is realized by utilizing the resin adsorption towers which are connected in series.

Description

Technical Field

[0001] The utility model relates to the technical field of cationic etherifying agent production, in particular to an adsorption and purification device for cationic etherifying agents. Background Art

[0002] 3-Chloro-2-hydroxypropyltrimethylammonium chloride is a cationic etherifying agent containing quaternary ammonium ions. It is primarily used to modify substrates such as starch, cellulose, guar gum, and polyacrylamide, and to prepare a variety of functional chemicals. These modified functional chemicals are widely used in the papermaking industry, daily chemicals, textiles, petroleum, water treatment, and other fields. In the textile field, 3-Chloro-2-hydroxypropyltrimethylammonium chloride is commonly used to cationic-modify fabric fibers to improve the dye uptake and fixation rate of anionic dyes, reducing or even eliminating the use of inorganic salts in the printing and dyeing process. 3-Chloro-2-hydroxypropyltrimethylammonium chloride is also used to cationic-modify starch to prepare warp yarn sizing agents.

[0003] There are two main methods for synthesizing 3-chloro-2-hydroxypropyltrimethylammonium chloride: Method 1 uses trimethylamine hydrochloride and epichlorohydrin as starting materials to synthesize 3-chloro-2-hydroxypropyltrimethylammonium chloride through a one-step reaction; Method 2 uses trimethylamine and hydrogen chloride as starting materials in a first step to synthesize trimethylamine hydrochloride, and then uses the synthesized trimethylamine hydrochloride and epichlorohydrin as reactants in a second step to synthesize 3-chloro-2-hydroxypropyltrimethylammonium chloride. Compared with Method 2, Method 1 offers the advantages of milder reaction conditions and greater reaction controllability, making it widely used in the industrial synthesis of 3-chloro-2-hydroxypropyltrimethylammonium chloride. During the synthesis of 3-chloro-2-hydroxypropyltrimethylammonium chloride using Method 1, epichlorohydrin undergoes a ring-opening addition reaction with free HCl to produce 1,3-dichloro-2-propanol as a byproduct. When 3-chloro-2-hydroxypropyltrimethylammonium chloride is used to cationic starch, 1,3-dichloro-2-propanol will undergo a cross-linking reaction with the starch, seriously affecting the application performance of the cationic starch. Utility Model Content

[0004] Aiming at the technical problem that the content of the by-product 1,3-dichloro-2-propanol is relatively high in 3-chloro-2-hydroxypropyltrimethylammonium chloride synthesized by a one-step method in the prior art, the utility model provides an adsorption purification device for a cationic etherifying agent. The device comprises at least two resin adsorption towers, which are connected end to end to form a closed loop. The multi-stage purification of the cationic etherifying agent is achieved by using the series-connected resin adsorption towers.

[0005] The technical solution of this utility model is as follows:

[0006] A cationic etherifying agent adsorption and purification device includes at least two resin adsorption towers, each of which is connected end-to-end via a circulation pipeline to form a closed loop; the top of each resin adsorption tower is respectively connected to a low-pressure steam main, a compressed air main, and a cationic etherifying agent pure product discharge pipe, and the bottom of each resin adsorption tower is respectively connected to a cationic etherifying agent feed main and a cationic etherifying agent crude product discharge pipe;

[0007] A control valve is installed on the circulation pipeline between two adjacent resin adsorption towers, connecting the cationic etherifying agent crude product discharge pipe to the cationic etherifying agent feed main pipe. Different resin adsorption towers can be filled with resins of the same or different polarities. When different resin adsorption towers are filled with resins of different polarities, the control valve can be adjusted to control the cationic etherifying agent liquid to flow along the polarity gradient between the resin adsorption towers.

[0008] Furthermore, the top of each resin adsorption tower is connected to the low-pressure steam main pipe through a low-pressure steam branch pipe, and the low-pressure steam main pipe can pass low-pressure steam from the top of each resin adsorption tower into each resin adsorption tower to desorb the resin, thereby realizing resin regeneration; the top of each resin adsorption tower is connected to the compressed air main pipe through a compressed air branch pipe, and when the compressed air in the compressed air main pipe enters the interior of the resin adsorption tower from the top of the adsorption-saturated resin adsorption tower, the cationic etherifying agent liquid that does not participate in the adsorption separation in the resin adsorption tower can be removed from the top of the resin adsorption tower. The bottom is discharged into the cationic etherifying agent feed main pipe, thereby realizing the top material emptying of the resin adsorption tower; when the compressed air in the compressed air main pipe enters the interior of the empty resin adsorption tower from the top of the resin adsorption tower, the resin in the resin adsorption tower can be cooled; the top of each resin adsorption tower is connected to the cationic etherifying agent pure product discharge pipe through a pure product discharge branch pipe, and the cationic etherifying agent feed liquid enters the resin adsorption tower from the bottom of the resin adsorption tower for adsorption purification, and is then discharged from the top of the resin adsorption tower and enters the cationic etherifying agent pure product discharge pipe through the pure product discharge branch pipe.

[0009] Furthermore, each low-pressure steam branch pipe is provided with a low-pressure steam valve, and the low-pressure steam valves on each low-pressure steam branch pipe are independent of each other; each compressed air branch pipe is provided with a compressed air valve, and the compressed air valves on each compressed air branch pipe are independent of each other; each pure product discharge branch pipe is provided with a pure product discharge valve, and the discharge valves on each pure product discharge branch pipe are independent of each other.

[0010] Furthermore, the bottom of each resin adsorption tower is connected to the cationic etherifying agent feed main pipe through a feed branch pipe; the bottom of each resin adsorption tower is connected to the cationic etherifying agent crude product discharge pipe through a crude product discharge branch pipe.

[0011] Furthermore, each feed branch pipe is provided with a feed valve, and the feed valves on each feed branch pipe are independent of each other; each crude product discharge branch pipe is provided with a discharge valve, and the discharge valves on each crude product discharge branch pipe are independent of each other.

[0012] Furthermore, a drain valve and an exhaust valve are provided at the bottom of each resin adsorption tower, and the drain valve is connected to the desorption liquid collection tank through a pipeline. The exhaust valve is used to adjust the air pressure in the resin adsorption tower to maintain the air pressure balance in the resin adsorption tower.

[0013] Furthermore, a condensing device is provided on the pipeline between the drain valve and the desorption liquid collecting tank, and is used to cool the desorption liquid discharged from the resin adsorption tower.

[0014] Furthermore, each resin adsorption tower is provided with a pressure drop measuring device for detecting the internal pressure drop of the resin adsorption tower, and judging whether the resin in the resin adsorption tower has reached adsorption saturation according to the internal pressure drop.

[0015] The beneficial effects of the present invention are:

[0016] The utility model provides an adsorption and purification device for a cationic etherifying agent, which connects at least two resin adsorption towers end to end to form a closed loop, and can perform step-by-step adsorption purification on a cationic etherifying agent feed liquid, which is beneficial to improving the purity of the cationic etherifying agent feed liquid; a control valve is provided on a circulation pipeline between two adjacent resin adsorption towers, and the flow direction of the cationic etherifying agent feed liquid between the resin adsorption towers is regulated by the control valve to ensure that the cationic etherifying agent feed liquid flows unidirectionally between the resin adsorption towers; the top of each resin adsorption tower is respectively connected to a low-pressure steam main pipe, and the low-pressure steam can be used to desorb the adsorption saturated resin adsorption tower; the top of each resin adsorption tower is respectively connected to a compressed air main pipe, and the compressed air can be used to empty the resin adsorption tower or cool the resin; The tops of the resin adsorption towers are respectively connected to the cationic etherifying agent pure product discharge pipes, so that cationic etherifying agent pure products of different purities can be collected from any one or more resin adsorption towers; the low-pressure steam in the low-pressure steam main pipe and the compressed air in the compressed air main pipe can directly enter any one or more resin adsorption towers, or can circulate among the multiple resin adsorption towers along a closed loop; the bottoms of the resin adsorption towers are respectively connected to the cationic etherifying agent feed main pipes, so that cationic etherifying agent liquid can be injected into any one or more resin adsorption towers as needed; the bottoms of the resin adsorption towers are respectively connected to the cationic etherifying agent crude product discharge pipes, so that cationic etherifying agent liquid of different purified grades discharged from the tops of the resin adsorption towers can be collected as needed.

[0017] The utility model not only realizes the graded adsorption purification of the cationic etherifying agent liquid, but also realizes the multi-stage utilization of low-pressure steam and compressed air, thereby reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 Schematic diagram of the connection relationship of the adsorption purification device for the cationic etherifying agent in Example 1.

[0020] In the figure, 1- low-pressure steam main pipe, 2- compressed air main pipe, 3- first resin adsorption tower, 4- cationic etherifying agent feed main pipe, 5- cationic etherifying agent crude product discharge pipe, 6- cationic etherifying agent pure product discharge pipe, 7- connecting pipe, 8- first drain valve, 9- first exhaust valve, 10- second drain valve, 11- second exhaust valve, 12- third drain valve, 13- third exhaust valve, 14- desorption liquid collection tank. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the following will be combined with the drawings of the embodiments of the present invention to clearly and completely describe the technical solutions of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0022] Example 1

[0023] A cationic etherifying agent adsorption and purification device includes a first resin adsorption tower 3, a second resin adsorption tower, and a third resin adsorption tower. The first resin adsorption tower 3, the second resin adsorption tower, and the third resin adsorption tower are each equipped with a pressure drop detector. The first resin adsorption tower 3, the second resin adsorption tower, and the third resin adsorption tower are each filled with macroporous resins of the same polarity. A first multi-tube butt joint is installed at the top of the first resin adsorption tower 3, a second multi-tube butt joint is installed at the top of the second resin adsorption tower, and a third multi-tube butt joint is installed at the top of the third resin adsorption tower. The first multi-tube butt joint installed on the first resin adsorption tower 3 is connected to the bottom feed inlet of the second resin adsorption tower via a first circulation pipeline. The second multi-tube butt joint installed on the second resin adsorption tower is connected to the bottom feed inlet of the third resin adsorption tower via a second circulation pipeline. The third multi-tube butt joint installed on the third resin adsorption tower is connected to the bottom feed inlet of the first resin adsorption tower 3 via a connecting pipe 7. The first circulation pipeline, the second circulation pipeline, and the connecting pipe 7 are respectively equipped with a first control valve, a second control valve, and a third control valve.

[0024] The first, second, and third multi-tube butt joints are connected to the low-pressure steam main pipe 1 through the first, second, and third low-pressure steam branches, respectively. The first, second, and third low-pressure steam branches are each equipped with a first, second, and third low-pressure steam valve, respectively, which are independent of each other. The first, second, and third multi-tube butt joints are connected to the compressed air main pipe 2 through the first, second, and third compressed air branches, respectively. The first, second, and third multi-tube butt joints are each equipped with a first, second, and third compressed air valve, respectively, which are independent of each other. The first multi-tube butt joint, the second multi-tube butt joint and the third multi-tube butt joint are respectively connected to the cationic etherifying agent pure product discharge pipe 6 through the first pure product discharge branch pipe, the second pure product discharge branch pipe and the third pure product discharge branch pipe. The cationic etherifying agent pure product discharge pipe 6 is connected to the cationic etherifying agent pure product collection tank. The first pure product discharge branch pipe, the second pure product discharge branch pipe and the third pure product discharge branch pipe are respectively provided with a first pure product discharge valve, a second pure product discharge valve and a third pure product discharge valve which are independent of each other.

[0025] A fourth, fifth, and sixth multi-tube butt joints are respectively provided at the bottom of the first resin adsorption tower 3, the bottom of the second resin adsorption tower, and the bottom of the third resin adsorption tower. The fourth, fifth, and sixth multi-tube butt joints are connected to the cationic etherifying agent feed main 4 via a first, second, and third feed branch pipes, respectively. The first, second, and third feed branches are each equipped with a first, second, and third independent feed valve. The fourth, fifth, and sixth multi-tube butt joints are connected to the crude cationic etherifying agent discharge pipe 5 via the first, second, and third crude product discharge branches, respectively. A valve is provided at each end of the crude cationic etherifying agent discharge pipe 5. The first, second, and third crude product discharge branches are each equipped with a first, second, and third independent discharge valve. The crude cationic etherifying agent discharge pipe 5 is connected to a crude cationic etherifying agent collection tank, which is in turn connected to the main cationic etherifying agent feed pipe 4. A first drain valve 8 and a first exhaust valve 9, a second drain valve 10 and a second exhaust valve 11, and a third drain valve 12 and a third exhaust valve 13 are also provided at the bottom of the first resin adsorption tower 3, the bottom of the second resin adsorption tower, and the bottom of the third resin adsorption tower, respectively. The first drain valve 8, the second drain valve 10, and the third drain valve 12 are all connected to the desorbed liquid collection tank 14 via pipelines. Jacketed condensers are respectively provided on the pipelines between the first drain valve 8, the second drain valve 10, and the third drain valve 12 and the desorbed liquid collection tank 14.

[0026] The first control valve, the second control valve, the third control valve, the first low-pressure steam valve, the second low-pressure steam valve, the third low-pressure steam valve, the first compressed air valve, the second compressed air valve, the third compressed air valve, the first pure product discharge valve, the second pure product discharge valve, the third pure product discharge valve, the first feed valve, the second feed valve, the third feed valve, the first discharge valve, the second discharge valve, the third discharge valve, the first liquid discharge valve and the first exhaust valve, the second liquid discharge valve and the second exhaust valve, the third liquid discharge valve and the third exhaust valve are all electric valves, and the electric valves and the pressure drop detector are electrically connected to the PLC controller (not shown in the figure).

[0027] Working Principle: The first feed valve is opened, and the cationic etherifying agent feed liquid in the cationic etherifying agent feed main enters the first resin adsorption tower through the first feed branch for primary separation and purification. Byproducts are removed, resulting in a purified primary feed liquid. The cationic etherifying agent feed liquid contains 3-chloro-2-hydroxypropyltrimethylammonium chloride, and the main byproduct is 1,3-dichloro-2-propanol. The first control valve is opened, and the purified primary feed liquid is discharged from the top of the first resin adsorption tower. It then enters the second resin adsorption tower through the first circulation line for secondary separation and purification, where byproducts are further removed, resulting in a purified secondary feed liquid. The second control valve is opened, and the purified secondary feed liquid enters the third resin adsorption tower through the second circulation line for tertiary separation and purification. Byproducts are again removed, resulting in a purified tertiary feed liquid, completing the first separation and purification cycle. The third control valve is opened, and the purified tertiary feed liquid flows back to the first resin adsorption tower through the connecting pipe. This process is repeated to complete the next separation and purification cycle until the purified feed liquid meets the purity standard. During the multi-stage separation and purification process of the cationic etherifying agent feed liquid, the first pure product discharge valve, the second pure product discharge valve or the third pure product discharge valve can be opened as needed to discharge the purified feed liquid in the first resin adsorption tower, the second resin adsorption tower or the third resin adsorption tower, and the discharged purified feed liquid is transported to the cationic etherifying agent pure product collection tank through the cationic etherifying agent pure product discharge pipe. When the resin in the first resin adsorption tower, the second resin adsorption tower or the third resin adsorption tower is saturated with adsorption, the corresponding compressed air valve, the corresponding discharge valve and the valve of the cationic etherifying agent discharge pipe close to the cationic etherifying agent crude product collecting tank are first opened, and compressed air enters from the top of the corresponding resin adsorption tower to discharge the cationic etherifying agent crude product liquid remaining in the resin adsorption tower, completing the top material emptying of the resin adsorption tower. The discharged cationic etherifying agent crude product liquid enters the cationic etherifying agent crude product collecting tank through the corresponding discharge branch pipe and the cationic etherifying agent crude product discharge pipe for standby use. The valve of the cationic etherifying agent discharge pipe away from the cationic etherifying agent crude product collecting tank is opened, and the cationic etherifying agent crude product liquid in the cationic etherifying agent crude product collecting tank can be passed into the unsaturated resin adsorption tower for separation and purification. After the resin adsorption tower is emptied, the corresponding low-pressure steam valve is opened. Low-pressure steam enters from the top of the resin adsorption tower to desorb the resin in the resin adsorption tower. Continue to introduce low-pressure steam into the resin adsorption tower and accumulate it to a certain amount. The gas-liquid mixture containing 1,3-dichloro-2-propanol in the resin adsorption tower is discharged from the bottom of the resin adsorption tower. At this time, the corresponding drain valve is opened to transfer the gas-liquid mixture to the desorption liquid collection tank. Before entering the desorption liquid collection tank, the gas-liquid mixture is cooled by a jacketed condenser to form a desorption liquid that enters the desorption liquid collection tank, completing the steam stripping. After the steam stripping is completed, compressed air is introduced into the resin adsorption tank again to cool the resin in the resin adsorption tower and complete the resin regeneration.After the resin is regenerated, the control valve between the resin adsorption tower of the resin regeneration and the resin adsorption tower of the next stage is closed, and the feed valve corresponding to the resin adsorption tower of the next stage is opened to perform a new round of separation and purification on the cationic etherification agent feed liquid. The purified liquid after the three-stage separation and purification is discharged from the top of the resin adsorption tower of the resin regeneration.

[0028] Although the present invention has been described in detail with reference to the accompanying drawings and in conjunction with preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, persons of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and such modifications or substitutions shall fall within the scope of the present invention. Any changes or substitutions that can be easily conceived by persons skilled in the art within the technical scope disclosed in the present invention shall fall within the scope of protection of the present invention.

Claims

1. An adsorption purification device for a cationic etherifying agent, comprising a resin adsorption tower, characterized in that: There are at least two resin adsorption towers, and the resin adsorption towers are connected end to end through a circulation pipeline to form a closed loop; the top of each resin adsorption tower is respectively connected to a low-pressure steam main, a compressed air main, and a cationic etherifying agent pure product discharge pipe, and the bottom of each resin adsorption tower is respectively connected to a cationic etherifying agent feed main and a cationic etherifying agent crude product discharge pipe; A control valve is provided on the circulation pipeline between two adjacent resin adsorption towers; and the cationic etherifying agent crude product discharge pipe is connected with the cationic etherifying agent feed main pipe.

2. The adsorption purification device for a cationic etherifying agent according to claim 1, wherein: The top of each resin adsorption tower is connected to the low-pressure steam main pipe through a low-pressure steam branch pipe, the top of each resin adsorption tower is connected to the compressed air main pipe through a compressed air branch pipe, and the top of each resin adsorption tower is connected to the pure cationic etherifying agent discharge pipe through a pure product discharge branch pipe.

3. The adsorption purification device for a cationic etherifying agent according to claim 2, wherein: Each low-pressure steam branch pipe is provided with a low-pressure steam valve, each compressed air branch pipe is provided with a compressed air valve, and each pure product discharge branch pipe is provided with a pure product discharge valve.

4. The adsorption purification device for a cationic etherifying agent according to claim 1, wherein: The bottom of each resin adsorption tower is connected to the cationic etherifying agent feed main pipe through a feed branch pipe; the bottom of each resin adsorption tower is connected to the cationic etherifying agent crude product discharge pipe through a crude product discharge branch pipe.

5. The adsorption purification device for a cationic etherifying agent according to claim 4, characterized in that: Each feed branch pipe is provided with a feed valve, and each crude product discharge branch pipe is provided with a discharge valve.

6. The adsorption purification device for a cationic etherifying agent according to claim 1, characterized in that: A drain valve and an exhaust valve are respectively provided at the bottom of each resin adsorption tower, and the drain valve is connected to the desorption liquid collection tank through a pipeline.

7. The adsorption purification device for a cationic etherifying agent according to claim 6, characterized in that: A condensing device is provided on the pipeline between the drain valve and the desorption liquid collecting tank.

8. The adsorption purification device for a cationic etherifying agent according to claim 1, characterized in that: Each resin adsorption tower is equipped with a pressure drop measuring device.

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