Dimethylphenol decolorizing system
By designing a dicresol decolorization system and using a combination of dicresol buffer tank and decolorizer, the problem of low quality of dicresol products in crude phenol refined is solved, high-quality decolorization effect is achieved, and the market value of the product is enhanced.
Patent Information
- Application Number
- CN202520175820.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-27
- Publication Date
- 2025-03-04
- Estimated Expiration
- 2035-01-27
AI Technical Summary
During the purification process of crude phenol isolated from coal tar, ordinary dicresol contains a large amount of impurities, resulting in low product quality, turbid color, and low market added value.
A dicresol decolorization system was designed. The product quality of dicresol produced in the dicresol tower was improved by temporarily storing the dicresol buffer tank after adding decolorizing agent.
The decolorization effect of dicresol is achieved, making the product color look colorless to brown-red transparent liquid, and the holding time is no less than 72 hours, which improves product revenue and competitiveness.
Smart Images
Figure CN222550877U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of crude phenol refining, in particular to a xylenol decolorization system. Background Art
[0002] Decolorizer is a commonly used chemical reagent, and its main function is to remove the color of dyes, pigments or other organic compounds. The decolorization principle of decolorizer can be divided into many types such as redox reaction, reduction decomposition reaction, acid-base neutralization reaction, etc. Among them, redox reaction is the most common one. Decolorizer can reduce or oxidize the chromophore in the dye or pigment through redox reaction, so that its molecular structure changes and loses color. For example, sodium sulfite is a commonly used reduction decolorizer, which can reduce the double bond in the dye or the ketone group on the benzene ring to an alcohol group, thereby turning it into a colorless compound. In addition, acid-base neutralization reaction is also a common decolorization principle. Some organic dyes or pigments are acidic or alkaline. When the acidic or alkaline substances in the decolorizer are neutralized with them, the molecular structure changes, causing them to lose color. For example, sodium hydroxide can neutralize the acid group in the acid dye and turn it into a colorless compound.
[0003] In the refining process of crude phenol separated from coal tar, the ordinary xylenol produced contains a large amount of impurities and is turbid brown-red in color. The product quality is low and the market added value is low. The decolorized xylenol product can not only meet the requirements of xylenol GB / T2600-2009, but also increase product profits and enhance product competitiveness. Utility Model Content
[0004] The utility model aims to provide a xylenol decolorization system.
[0005] The utility model is implemented by the following technical solutions:
[0006] A xylenol decolorization system comprises a crude xylenol tank, wherein the discharge port of the crude xylenol tank is connected to the liquid inlet of a xylenol reboiler, the discharge port of the xylenol reboiler is connected to the liquid inlet of a preheater, the discharge port of the preheater is connected to the liquid inlet of a xylenol tower, the bottom reflux outlet of the xylenol tower is connected to the reflux port of the xylenol reboiler, the exhaust port of the xylenol reboiler is connected to the air inlet of the xylenol tower, and the top of the xylenol tower is connected to the exhaust port of the xylenol reboiler. The gas outlet is connected to the air inlet of the cooler, the drain port of the cooler is connected to the liquid inlet of the xylenol reflux tank, the drain port of the xylenol reflux tank is connected to the liquid inlet of the xylenol buffer tank, the drain port of the xylenol buffer tank is connected to the liquid inlet of the xylenol reboiler; the liquid inlet of the xylenol reboiler is also connected to a metering pump, and the metering pump is connected to a decolorant storage tank; the drain port of the xylenol reflux tank is also connected to the liquid inlet of the decolorizing xylenol storage tank.
[0007] Preferably, the liquid discharge port of the xylenol reflux tank is also connected to the reflux port of the xylenol tower.
[0008] The utility model has the advantages that the xylenol produced by the xylenol tower is temporarily stored in a xylenol buffer tank, a decolorizing agent is added and then decolorized, so that the product quality of the xylenol is improved, and decolorized xylenol is obtained. The product color is a colorless to brown-red transparent liquid, and the retention time is not less than 72 hours, thereby improving product revenue and enhancing product competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 It is a structural schematic diagram of the utility model.
[0010] In the figure: crude xylenol tank 1, xylenol reboiler 2, preheater 3, xylenol tower 4, cooler 5, xylenol reflux tank 6, xylenol buffer tank 7, metering pump 8, decolorant storage tank 9, decolorized xylenol storage tank 10. DETAILED DESCRIPTION
[0011] like Figure 1 As shown, a xylenol decolorization system comprises a crude xylenol tank 1, a discharge port of the crude xylenol tank 1 is connected to a liquid inlet of a xylenol reboiler 2, a discharge port of the xylenol reboiler 2 is connected to a liquid inlet of a preheater 3, a discharge port of the preheater 3 is connected to a liquid inlet of a xylenol tower 4, a bottom reflux outlet of the xylenol tower 4 is connected to a reflux outlet of the xylenol reboiler 2, an exhaust port of the xylenol reboiler 2 is connected to an air inlet of the xylenol tower 4, and a top gas outlet of the xylenol tower 4 is connected to a gas outlet of the xylenol reboiler 2. The outlet is connected to the air inlet of the cooler 5, the drain port of the cooler 5 is connected to the liquid inlet of the xylenol reflux tank 6, the drain port of the xylenol reflux tank 6 is connected to the liquid inlet of the xylenol buffer tank 7, the drain port of the xylenol buffer tank 7 is connected to the liquid inlet of the xylenol reboiler 2; the liquid inlet of the xylenol reboiler 2 is also connected to the metering pump 8, the metering pump 8 is connected to the decolorant storage tank 9; the drain port of the xylenol reflux tank 6 is also connected to the liquid inlet of the decolorized xylenol storage tank 10;
[0012] During the production of xylenol, crude xylenol is first sent to crude xylenol tank 1 for temporary storage, and then sent to xylenol reboiler 2 for heating, and the generated gas is sent to xylenol tower 4 through the air inlet of xylenol tower 4, and the liquid is sent to preheater 3 through pump for further heating and then sent to xylenol tower 4 from the liquid inlet of xylenol tower 4, the bottom liquid in xylenol tower 4 is refluxed to xylenol reboiler 2, and the top gas of xylenol tower 4 enters cooler 5 for liquefaction and is sent to xylenol reflux tank 6, at which time the valve at the inlet of xylenol buffer tank 7 is in an open state, and the xylenol in xylenol reflux tank 6 is sent to xylenol buffer tank 7; after the xylenol buffer tank 7 is full, the xylenol tower 4 is stopped;
[0013] Then, the xylenol in the xylenol buffer tank 7 is sent to the xylenol reboiler 2, and the decolorant is added to the xylenol reboiler 2 by the decolorant storage tank 9 at a mass ratio of 0.5-2.0% by mass through the metering pump 8, and the temperature of the liquid in the xylenol reboiler 2 is raised to 120-140° C. After reacting for 2-4 hours, the system starts to decolorize the product, and the material in the xylenol reboiler 2 is heated by the xylenol reboiler 2, and the above xylenol production process is repeated to obtain decolorized xylenol and send it to the xylenol reflux tank 6, at which time the valve at the inlet of the xylenol buffer tank 7 is in a closed state, and the valve at the inlet of the decolorized xylenol storage tank 10 is in an open state, and the decolorized xylenol is sent to the decolorized xylenol storage tank 10;
[0014] The xylenol produced by the xylenol tower 4 is temporarily stored in the xylenol buffer tank 7, and then a decolorizing agent is added for decolorization, thereby improving the product quality of the xylenol, obtaining decolorized xylenol, the product color of which is a colorless to brownish red transparent liquid, and the retention time is not less than 72 hours, thereby improving the product profit and enhancing the product competitiveness.
[0015] The discharge port of the xylenol reflux tank 6 is also connected to the reflux port of the xylenol tower 4, and the material in the xylenol reflux tank 6 is sent into the xylenol tower 4 through the reflux port of the xylenol tower 4 to maintain the material balance of the xylenol tower 4 and improve the product quality.
[0016] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A xylenol decolorization system, characterized in that: The invention comprises a crude xylenol tank, wherein the discharge port of the crude xylenol tank is connected to the liquid inlet of a xylenol reboiler, the discharge port of the xylenol reboiler is connected to the liquid inlet of a preheater, the discharge port of the preheater is connected to the liquid inlet of a xylenol tower, the bottom reflux outlet of the xylenol tower is connected to the reflux outlet of the xylenol reboiler, the exhaust port of the xylenol reboiler is connected to the air inlet of the xylenol tower, the top gas outlet of the xylenol tower is connected to the cooling air outlet, and the bottom gas outlet of the xylenol tower is connected to the cooling air outlet. The air inlet of the cooler is connected, the drain port of the cooler is connected to the liquid inlet of the xylenol reflux tank, the drain port of the xylenol reflux tank is connected to the liquid inlet of the xylenol buffer tank, and the drain port of the xylenol buffer tank is connected to the liquid inlet of the xylenol reboiler; the liquid inlet of the xylenol reboiler is also connected to a metering pump, and the metering pump is connected to a decolorant storage tank; the drain port of the xylenol reflux tank is also connected to the liquid inlet of the decolorizing xylenol storage tank.
2. A xylenol decolorization system according to claim 1, characterized in that, The liquid discharge port of the xylenol reflux tank is also connected to the reflux port of the xylenol tower.