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CN-122011359-A - Method and device for refining polyether polyols

CN122011359ACN 122011359 ACN122011359 ACN 122011359ACN-122011359-A

Abstract

The invention relates to the field of refined polyether polyol, and discloses a method and a device for refining polyether polyol. The method comprises the steps of sequentially neutralizing, filtering and removing ions from crude polyether polyol. The device comprises a mixing unit, a filtering unit and an ion removing unit, wherein the mixing unit is used for mixing crude polyether polyol with a neutralizing agent, the filtering unit is used for filtering materials passing through the mixing unit, and the ion removing unit is used for removing metal ions from the materials passing through the filtering unit. The method and the device for refining the polyether polyol have the characteristics of low production cost, high production efficiency, capability of remarkably reducing the content of volatile organic compounds in the polyether polyol, greatly reducing the loss of polyether, and low content of volatile organic compounds, low odor and low alkali metal residue.

Inventors

  • GAO PAN
  • LI XIAOHONG
  • WANG HONGTAO
  • YU ZHINAN

Assignees

  • 中国石油化工股份有限公司
  • 中石化（上海）石油化工研究院有限公司

Dates

Publication Date
20260512
Application Date
20241111

Claims (10)

  1. 1. A process for refining polyether polyols, the process comprising: and (3) neutralizing, filtering and ion removing the crude polyether polyol in sequence.
  2. 2. The method of claim 1, wherein, Ion removing treatment is carried out on the filtered material by adopting ion removing fibers, wherein the material of the ion removing fibers comprises anionic groups, and the mass ratio of the anionic groups is preferably 0.1-2%; preferably, the method comprises the steps of, The ion removing fiber comprises at least one ion removing fiber layer, preferably at least three ion removing fiber layers which are closely connected along the material flow direction and used for capturing a metal ion disperse phase, a growth layer used for further expanding the growth of the metal ion disperse phase and a release layer used for rapidly discharging the metal ions passing through the growth layer; More preferably, the process is carried out, The fiber porosity of the capturing layer is 0.35-0.75, and/or The fiber porosity of the growth layer is 0.65-0.95, and/or The fiber porosity of the release layer is 0.25-0.45.
  3. 3. The method of claim 2, wherein, The total thickness of the ion-removed fibers is 0.01-15 cm, preferably 4-10 cm; Preferably, the ratio of the thickness of the capturing layer, the thickness of the growing layer and the thickness of the release layer in the ion-removing fiber is (0-1): 1 (0-1); And/or Passing the material through the ion-removing fiber at an included angle of 0-45 degrees, preferably 5-15 degrees, to the horizontal direction; And/or The operating conditions of the ion removal treatment include: the temperature is 70-150 ℃, preferably 85-135 ℃, and/or the pressure is 0.1-1 mpa.
  4. 4. A method according to any one of claim 1 to 3, wherein, The method also comprises the steps of carrying out distribution treatment on the materials before ion removal treatment; Preferably, the distribution treatment comprises passing the material before ion removal treatment through a distribution plate with an aperture ratio of 20-80%, preferably a distribution plate with an aperture ratio of 45-75%, more preferably a distribution hole with a pore diameter of 0.5-5 cm; And/or The method also comprises the step of carrying out reinforced separation treatment on the materials subjected to ion removal treatment; Preferably, the reinforced separation treatment is to pass through a reinforced separation plate with the surface subjected to hydrophilic modification, and preferably the surface water contact angle of the reinforced separation plate is controlled to be 0-60 degrees, and more preferably controlled to be 0-10 degrees.
  5. 5. The method according to any one of claims 1 to 4, wherein, The content of polyether polyol in the crude polyether polyol is 0.98-0.995 kg/kg, and/or the content of metal ions is 1000-3000 mg/kg; And/or The filtering is to pass the material through a filtering filter element with the screening precision of 0.1-100 um, preferably 0.5-10 um; And/or The neutralization is to add the crude polyether polyol into a neutralizing agent for mixing; Preferably, the neutralizing agent comprises one or more of phosphoric acid solution, sulfuric acid solution, and adipic acid solution.
  6. 6. The method of claim 5, wherein, The mass content ratio of solute to water in the neutralization reagent is (0.15-6): 1, preferably (1-3): 1, and/or The mass content ratio of water to crude polyether polyol in the neutralized mixed solution is (0.01-0.3): 1, preferably (0.05-0.15): 1, and/or The operating conditions of the neutralization process include: at a temperature of 70 to 150 ℃, preferably 85 to 135 ℃, and/or The pressure is 0.1-1 MPa of gauge pressure.
  7. 7. The method according to any one of claims 1-6, wherein, The method also comprises the step of carrying out brine separation on the brine product after ion removal treatment; preferably, the brine is separated into multiple effect evaporation of the material; And/or The content of metal ions in the refined polyether polyol is less than or equal to 5mg/kg, formaldehyde is less than 1ppm, acetaldehyde is less than 1ppm, and acrolein is less than 1ppm; preferably, the loss of polyether after refining is less than or equal to 0.005kg/kg.
  8. 8. An apparatus for refining polyether polyol for use in the process of any of claims 1 to 7, comprising, in sequence: A mixing unit for mixing the crude polyether polyol with a neutralizing agent; A filtering unit for filtering the material passing through the mixing unit; And the ion removing unit is used for removing metal ions from the material passing through the filtering unit.
  9. 9. The apparatus of claim 8, wherein, The mixing unit comprises a mixing kettle, and/or The filter unit comprises a filter, wherein the filter adopts a filter element with the screening precision of 0.1-100 mu m, preferably a filter element with the screening precision of 0.5-10 mu m, and/or The ion removing unit comprises an ion remover, and a distribution plate, an ion removing fiber layer and a reinforced separation plate are sequentially arranged in the ion remover along the flow direction of the material.
  10. 10. The apparatus of claim 9, wherein, The mixing kettle is connected with the filter through a prefilter buffer tank, and/or The material passes along the transverse axis of the ion remover, the included angle between the transverse axis of the ion remover and the horizontal direction is fixed at 0-45 degrees, preferably 5-15 degrees, and the ion remover is obliquely and upwards fixed, and/or The device also comprises a multi-effect evaporator connected with a brine outlet of the ion remover, and preferably the ion remover is connected with the multi-effect evaporator through an evaporation buffer tank; preferably, the evaporation buffer tank is connected to the crude polyether polyol storage tank at an abnormal level.

Description

Method and device for refining polyether polyols Technical Field The invention relates to the field of refining polyether polyol, in particular to a method and a device for refining polyether polyol. Background Polyether polyol is one of main synthetic raw materials of polyurethane, and hydroxyl groups of the polyether polyol react with polyisocyanate to form polyurethane products such as foamed plastics, synthetic rubber, paint, adhesive, synthetic leather, chemical fiber and the like. In addition, polyether polyols may also be used as nonionic surfactants, lubricants, liquid fluids, heat exchange fluids, and the like. Polyether polyol develops rapidly and is widely applied to various fields of national economy. The polyether polyol is generally synthesized by ring-opening polymerization of epoxides such as ethylene oxide, propylene oxide and the like on an initiator containing an active hydrogen compound by using alkali metal, alkaline earth metal or hydroxide thereof as a catalyst. When the polyether polyol reacts with isocyanate to produce polyurethane, if the content of metal ions such as potassium, sodium and the like mixed in the polyether polyol is higher, the reaction is violent, and the polyurethane product is scrapped due to caking. Therefore, the crude polyether polyol needs to be subjected to a refining treatment to remove metal ions such as potassium, sodium, etc. At present, the refining method of polyether polyol mainly comprises a neutralization-filtration method, wherein an acidic neutralization reagent is added into crude polyether polyol to neutralize alkaline metal ions in the crude polyether to generate alkali metal salt, the alkali metal salt is dehydrated in vacuum to crystallize and separate out the alkali metal salt, and finally, solid alkali metal salt is removed through filtration to obtain a refined polyether polyol product. CN 101775132a describes a refining process without adding acid, at 60-120 ℃ using water accounting for 0.1-10% of the total mass of the crude ether polyol and using two adsorbents, performing 2-3 times of adsorption, filtering to obtain low-odor polyether polyol. The used adsorbents are magnesium silicate and diatomite, but the adsorption times are too many, and the cost is relatively high. The refining method has complex flow, needs longer dehydration time to improve the filtering effect of alkali metal salt so as to improve the crystal grain diameter, and is easy to cause the loss of polyether polyol in the filtering process due to the high viscosity of the polyether polyol. Therefore, the existing refining method of polyether polyol has the problems of complex treatment steps, long treatment time, damaged yield and the like. Disclosure of Invention The invention aims to solve the problems of complex treatment steps, long treatment time, damaged yield and the like in the prior art, and provides a method for refining polyether polyol, which has the characteristics of simple treatment steps, low impurity content and low polyether loss rate. In order to achieve the above object, the present invention provides, in one aspect, a method for refining a polyether polyol, the method comprising: and (3) neutralizing, filtering and ion removing the crude polyether polyol in sequence. In a second aspect, the present invention provides an apparatus for refining polyether polyol for use in the process of the present invention, the apparatus comprising: A mixing unit for mixing the crude polyether polyol with a neutralizing agent; A filtering unit for filtering the material passing through the mixing unit; And the ion removing unit is used for removing metal ions from the material passing through the filtering unit. Compared with the prior art, the invention has at least the following beneficial effects: (1) The method and the device for refining the polyether polyol have the characteristics of low production cost, high production efficiency, capability of remarkably reducing the content of volatile organic compounds in the polyether polyol, greatly reducing the loss of polyether, and low content of volatile organic compounds, low odor and low alkali metal residue. (2) The method and the device have simple operation, less time consumption and less investment. Drawings FIG. 1 is a schematic flow diagram of a refined polyether polyol in a preferred embodiment of the present invention. Description of the reference numerals 1. Mixing still 2, filter A, 3, filter B, 4, ion remover A, 5, ion remover B, 6, prefilter buffer tank, 7, evaporation buffer tank, 8, multiple effect evaporator, 9, crude polyether polyol storage tank, 10, filter element, 11, distribution plate, 12, ion removing fiber, 13, reinforced separation plate, 14, liquid level meter, 15, abnormal liquid level, 16, ion remover A polyether polyol outlet, 17, ion remover B polyether polyol outlet, 18, ion remover A brine outlet, 19, ion remover B brine outlet, 20, water outlet, 21, salt outlet. Detailed Description