WO2015152258A1 - フッ素含有水溶液の処理方法 - Google Patents
フッ素含有水溶液の処理方法 Download PDFInfo
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- WO2015152258A1 WO2015152258A1 PCT/JP2015/060163 JP2015060163W WO2015152258A1 WO 2015152258 A1 WO2015152258 A1 WO 2015152258A1 JP 2015060163 W JP2015060163 W JP 2015060163W WO 2015152258 A1 WO2015152258 A1 WO 2015152258A1
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- C07F7/00—Compounds containing elements of Groups 4 or 14 of the Periodic System
- C07F7/02—Silicon compounds
- C07F7/08—Compounds having one or more C—Si linkages
- C07F7/12—Organo silicon halides
- C07F7/16—Preparation thereof from silicon and halogenated hydrocarbons direct synthesis
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/68—Treatment of water, waste water, or sewage by addition of specified substances, e.g. trace elements, for ameliorating potable water
- C02F1/683—Treatment of water, waste water, or sewage by addition of specified substances, e.g. trace elements, for ameliorating potable water by addition of complex-forming compounds
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/40—Mixing liquids with liquids; Emulsifying
- B01F23/45—Mixing liquids with liquids; Emulsifying using flow mixing
- B01F23/451—Mixing liquids with liquids; Emulsifying using flow mixing by injecting one liquid into another
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/40—Mixing liquids with liquids; Emulsifying
- B01F23/45—Mixing liquids with liquids; Emulsifying using flow mixing
- B01F23/453—Mixing liquids with liquids; Emulsifying using flow mixing by moving the liquids in countercurrent
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
- B01F25/20—Jet mixers, i.e. mixers using high-speed fluid streams
- B01F25/21—Jet mixers, i.e. mixers using high-speed fluid streams with submerged injectors, e.g. nozzles, for injecting high-pressure jets into a large volume or into mixing chambers
- B01F25/211—Jet mixers, i.e. mixers using high-speed fluid streams with submerged injectors, e.g. nozzles, for injecting high-pressure jets into a large volume or into mixing chambers the injectors being surrounded by guiding tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
- B01F25/50—Circulation mixers, e.g. wherein at least part of the mixture is discharged from and reintroduced into a receptacle
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/34—Treatment of water, waste water, or sewage with mechanical oscillations
- C02F1/36—Treatment of water, waste water, or sewage with mechanical oscillations ultrasonic vibrations
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
- B01F2101/2204—Mixing chemical components in generals in order to improve chemical treatment or reactions, independently from the specific application
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/12—Halogens or halogen-containing compounds
- C02F2101/14—Fluorine or fluorine-containing compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/04—Flow arrangements
- C02F2301/046—Recirculation with an external loop
Definitions
- the present invention relates to a method for treating a fluorine-containing aqueous solution and an apparatus for treating the fluorine-containing aqueous solution.
- Non-Patent Document 1 a method in which calcium fluoride is precipitated by adding calcium to a fluorine-containing aqueous solution and adjusting the pH of the aqueous solution to neutral.
- Non-Patent Document 1 a method in which calcium fluoride is precipitated by adding calcium to a fluorine-containing aqueous solution and adjusting the pH of the aqueous solution to neutral.
- Patent Document 1 describes a method for purifying hydrochloric acid comprising a step of bringing a silicon compound such as trimethylchlorosilane into contact with hydrochloric acid containing hydrogen fluoride and a step of recovering a trialkylfluorosilane compound produced in the contacting step.
- the recovery step comprises a step of hydrolyzing the trialkylfluorosilane compound to convert it to a trialkylsilanol compound, and a step of condensing the trialkylsilanol compound to convert it to a hexaalkyldisiloxane compound.
- the trialkylchlorosilane compound is produced by chlorinating the hexaalkyldisiloxane compound obtained in step 1, and this trialkylchlorosilane compound is reused in the contacting step.
- high concentration hydrochloric acid of 25% by weight or more is required.
- Patent Document 2 discloses a fluorotrialkylsilane in which a fluorine-containing waste liquid is filled with a solid adsorbent supporting hexaalkyldisiloxane, the waste liquid is kept in an acidic state, air is blown into the liquid, and the liquid is scattered from the waste liquid.
- a method for treating a fluorine-containing waste liquid characterized in that is recovered in an alkaline liquid. This method requires as much as 3 hours to remove fluorine from the fluorine-containing waste liquid.
- this method requires handling of a solid adsorbent and a fluorotrialkylsilane that scatters with air, making the process complicated and costly. Can be.
- the reaction for obtaining trialkylfluorosilane by reacting hydrochloric acid containing hydrogen fluoride with trialkylchlorosilane in the contacting step is represented by the following formula (i).
- R 1 , R 2 and R 3 are the same or different and each represents an alkyl group having 1 to 4 carbon atoms. This reaction removes fluorine ions from hydrochloric acid.
- the trialkylfluorosilane produced by the reaction of the above formula (i) is recovered, and the trialkylfluorosilane is regenerated into a trialkylchlorosilane by the reactions represented by the following formulas (ii) to (iv).
- the recovered trialkylfluorosilane is hydrolyzed by a reaction represented by the following formula (ii) under neutral or basic conditions.
- a hexaalkyldisiloxane is obtained by condensing a trialkylsilanol obtained by hydrolysis by a reaction represented by the following formula (iii).
- Trimethylchlorosilane is obtained by chlorinating the obtained hexaalkyldisiloxane by a reaction represented by the following formula (iv).
- the trialkylchlorosilane regenerated in this way can be reused in the contact step described above.
- Trialkylchlorosilanes such as trimethylchlorosilane (hereinafter also referred to as TMCS) used in the method described in Patent Document 1 are known to be unstable substances that are easily hydrolyzed. For this reason, the method described in Patent Document 1 has a problem that it is difficult to handle trialkylchlorosilane.
- TMCS trimethylchlorosilane
- an additional treatment such as performing a reaction in a non-aqueous system or removing generated water with a dehydrating agent is performed. Cost.
- the present inventors have replaced the general formula R a R b R c SiOSiR d R e R f (wherein R a , R b , R c , R d , R e and R f instead of trialkylchlorosilane such as TMCS ).
- R a , R b , R c , R d , R e and R f instead of trialkylchlorosilane such as TMCS .
- Purification of the fluorine-containing aqueous solution using the disiloxane compound can be performed by reactions represented by the following formulas (I), (II) and (III-1) to (III-3).
- the reaction represented by the formula (I) the fluorine ion in the aqueous solution reacts with the disiloxane compound, and the monofluoro represented by the general formulas R a R b R c SiF and R d R e R f SiF
- a silane compound is produced. Since the monofluorosilane compound produced by this reaction is insoluble in water, it can be easily separated from the aqueous solution. As a result, a purified aqueous solution having a reduced fluorine concentration than before the reaction is obtained.
- the produced monofluorosilane compound is hydrolyzed by a reaction represented by the following formula (II) under basic conditions to produce a silanol compound.
- the produced silanol compound is dehydrated and condensed by the reactions represented by the following formulas (III-1) to (III-3) to produce a disiloxane compound.
- the disiloxane compound regenerated in this way can be reused in the reaction of formula (I).
- the regenerated disiloxane compound may be the same type as the original disiloxane compound, or may be a different type, or a mixture of a plurality of types of disiloxane compounds.
- the disiloxane compound is insoluble in water, it does not mix with the fluorine-containing aqueous solution and phase-separates. For this reason, the reaction between the fluorine ion in the fluorine-containing aqueous solution represented by the formula (I) and the disiloxane compound proceeds only at the interface between the organic phase containing the disiloxane compound and the aqueous phase containing the fluorine-containing aqueous solution. obtain. Furthermore, since the disiloxane compound is a stable compound, the reaction rate of the formula (I) is slower than the reaction of the formula (i) between trialkylchlorosilane and fluorine ions, and the reaction takes a long time. Therefore, it is difficult to efficiently treat a large amount of fluorine-containing waste liquid generated in the fluorine compound production process using the disiloxane compound.
- An object of the present invention is to provide an efficient treatment method for a fluorine-containing aqueous solution, which allows the reaction between fluorine ions in the fluorine-containing aqueous solution and a disiloxane compound to proceed in a short time.
- the inventors of the present invention greatly increased the chance of contact between fluorine ions and disiloxane compounds by vertically mixing the fluorine-containing aqueous solution and the disiloxane compound, and the fluorine ions and disiloxane compound in the fluorine-containing aqueous solution And the present invention has been completed.
- the fluorine-containing aqueous solution and the disiloxane compound are mixed to react the fluorine ions in the fluorine-containing aqueous solution with the disiloxane compound, whereby the first reaction containing the monofluorosilane compound is performed.
- a first reaction tank for obtaining a liquid comprising a conduit for discharging the liquid taken out from the first reaction tank into the first reaction tank, and having a first nozzle
- An apparatus for treating a fluorine-containing aqueous solution is provided that includes a first reaction vessel with a member attached to the tip of a conduit.
- the fluorine-containing aqueous solution and the disiloxane compound are mixed to react the fluorine ions in the fluorine-containing aqueous solution with the disiloxane compound, thereby containing the first monofluorosilane compound.
- An apparatus for treating a fluorine-containing aqueous solution includes a first tubular reactor, wherein:
- a first countercurrent reactor A fluorine-containing aqueous solution is supplied to the upper part of the first countercurrent reaction tower, a disiloxane compound is supplied to the lower part of the first countercurrent reaction tower, A purified aqueous solution in which an organic phase containing a disiloxane compound and a monofluorosilane compound is obtained at the top of the first counter-current reaction tower, and the fluorine concentration is lower than that of the fluorine-containing aqueous solution at the bottom of the first counter-current reaction tower
- An apparatus for treating a fluorine-containing aqueous solution including a first countercurrent reaction tower, wherein:
- an efficient method and apparatus for treating a fluorine-containing aqueous solution capable of allowing the reaction between the fluorine ion in the fluorine-containing aqueous solution and the disiloxane compound to proceed in a short time.
- FIG. 3 is a flowchart of a method according to an embodiment of the present invention. It is a schematic diagram of the apparatus which concerns on one Embodiment of this invention. It is a schematic diagram of the discharge member in one embodiment of the present invention. It is a schematic diagram which shows an example of arrangement
- FIG. 1 is a flowchart of a method for treating a fluorine-containing aqueous solution according to an embodiment of the present invention.
- the method of the present invention includes a reaction step.
- the method of the present invention may further include a first separation step, a regeneration step, and a second separation step.
- the reaction step is a step of obtaining a first reaction liquid containing a monofluorosilane compound by reacting fluorine ions in the fluorine-containing aqueous solution with a disiloxane compound.
- the fluorine-containing aqueous solution that can be treated by the method of the present invention is not particularly limited, and fluorine ions (F ⁇ ) and fluorine-containing such as SiF 6 2 ⁇ , BF 4 ⁇ , PF 6 ⁇ and SO 3 F ⁇
- Various aqueous solutions containing one or more ions such as aqueous solutions containing one or more of HF, H 2 SiF 6 , HBF 4 , HPF 6 and HSO 3 F can be treated.
- a fluorine-containing aqueous solution having a fluorine concentration of about 100 to 50,000 ppm can be treated to reduce the fluorine concentration in the aqueous solution to about 1 to 100 ppm.
- fluorine concentration means the fluorine ion and fluorine weight concentration in the target liquid.
- a fluorine concentration of 1000 ppm means that 1 g of fluorine ion and fluorine is present in 1 kg of the fluorine-containing aqueous solution. It means the concentration.
- the disiloxane compound usable in the present invention has a general formula R a R b R c SiOSiR d R e R f (wherein R a , R b , R c , R d , R e and R f are independent of each other). Selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a phenyl group, and hydrogen.
- disiloxane H 3 SiOSiH 3
- hexamethyldisiloxane ((H 3 C) 3 SiOSi (CH 3 ) 3
- HMDS hexaethyldisiloxane
- 1,1,3,3-tetramethyldisiloxane ((H 3 C) 2 HSiOSi (CH 3 ) 2 H)
- pentamethyldisiloxane ((H 3 C) 3 SiOSi (CH 3 ) 2 H) or the like
- a disiloxane compound may be used individually by 1 type, or may mix and use 2 or more types.
- hexamethyldisiloxane is relatively inexpensive and easily available, and is easy to handle because its safety, stability and boiling point are comparable to water. It is preferable to use it.
- the reaction between the fluorine ion and the disiloxane compound is represented by the following formula (I).
- the disiloxane compound is hexamethyldisiloxane (HMDS) (that is, when R a to R f are all methyl groups)
- the monofluorosilane compound produced by the reaction of formula (I) is trimethylfluorosilane (hereinafter referred to as “trimethylfluorosilane”). Also referred to as TMFS).
- the disiloxane compound Since the disiloxane compound is insoluble in water, it is immiscible with the fluorine-containing aqueous solution and phase-separated into an organic phase (light liquid) containing the disiloxane compound and an aqueous phase (heavy liquid) containing the fluorine-containing aqueous solution. Therefore, the reaction between the fluorine ion in the fluorine-containing aqueous solution and the disiloxane compound can proceed only at the interface between the organic phase and the aqueous phase. Furthermore, since the disiloxane compound is a stable compound, the reaction rate of the formula (I) is relatively slow and the reaction takes a long time.
- the present inventors can promote the reaction between the fluorine ions and the disiloxane compound, and can efficiently advance the reaction within a short time. I found out that I can do it. This is because vertical mixing causes the movement of fluorine ions and disiloxane compounds in the fluorine-containing aqueous solution in a direction perpendicular to the aqueous phase-organic phase interface, and as a result, fluorine-containing This is considered to be due to the fact that the contact opportunity between the aqueous solution fluorine ion and the disiloxane compound is greatly increased.
- mixing in the vertical direction means that the substance to be mixed moves in the vertical direction to such an extent that the aqueous phase and the organic phase are not phase-separated and a uniform mixed state is achieved.
- the direction of movement of the substance to be mixed may include a component other than the component in the vertical direction.
- various methods such as applying an external force and utilizing gravity can be employed. Specific examples include a mixing method using a nozzle, a mixing method using ultrasonic irradiation, and a counter-current contact method described below, but the method is not limited to these methods.
- the reaction step can be performed in the first reaction vessel 300 shown in FIG.
- the liquid taken out from the first reaction tank 300 is extracted from the first discharge member 100 including the first nozzle 1 in the liquid in the first reaction tank 300 in the vertical direction. This is performed by discharging the ink.
- the liquid can be taken out from the first reaction tank 300 through the conduit 6.
- the pump 61 may be used.
- “discharging in the vertical direction” means that the discharge direction of the liquid is such that the water phase and the organic phase are not phase-separated and a uniform mixed state is achieved. It means to bring about movement.
- the liquid discharge direction may include a component other than the component in the vertical direction.
- the liquid discharge direction is determined by the mounting angle of the discharge member.
- the attachment angle is preferably set to 0 ° to 60 °, more preferably 0 ° to 30 ° with respect to the vertical direction (vertically upward or vertically downward).
- the mounting angle is more preferably 0 ° (that is, vertically upward or vertically downward) with respect to the vertical direction.
- the attachment angle of the discharge member is 0 ° with respect to the vertical direction, the mixing in the vertical direction can be more effectively achieved.
- the “nozzle” means a member that is attached to the end of a conduit or the like and forms a jet (jet flow) by reducing the outlet of the fluid.
- the nozzle has a discharge port (orifice) at the tip.
- the nozzle is sometimes called a jet nozzle, an eductor, an ejector or the like.
- the configuration of the nozzle that can be used in the present embodiment is not particularly limited as long as the nozzle has an inner diameter and pressure resistance suitable for mixing in the vertical direction. The inner diameter and discharge pressure of the discharge port will be described later.
- FIG. 3A schematically shows discharge of the liquid from the discharge member 100.
- the liquid taken out from the first reaction tank 300 is discharged in the vertical direction into the liquid in the first reaction tank 300 from the tip 13 of the first nozzle 1 in the first discharge member 100.
- the discharge flow 3 discharged in the vertical direction from the tip 13 of the nozzle 1 forms a jet-like water flow (jet water flow).
- Jet water flow Such a jet-like discharge flow 3 can increase the flow rate ejected in the vertical direction by entraining (inhaling) the liquid present on the side.
- the discharge flow 3 whose flow rate is increased by the suction flow 31 from the side causes the vertical movement of the liquid in the reaction tank 300, and as a result, the liquid in the reaction tank 300 is mixed in the vertical direction. Can do.
- the liquid taken out from the lower part of the first reaction tank 300 is mixed with the first nozzle 1 in the upper part of the liquid in the first reaction tank 300. It is preferable that the discharge is performed by discharging vertically from the discharge member 100. In this way, the liquid is taken out from the lower part of the first reaction tank 300, and the taken-out liquid is discharged vertically downward in the upper part of the liquid in the first reaction tank 300, thereby mixing in the vertical direction. It can be further promoted.
- the specific gravity of the disiloxane compound is smaller than that of water, it tends to exist in a relatively large amount above the first reaction tank 300.
- the discharge flow 3 is carried out to the circumference
- Disiloxane compounds which can be present in large quantities can be sucked in as a suction stream 31 from the side.
- a vertically downward jet flow with the suction flow 31 that can contain a large amount of the disiloxane compound is provided, and the vertical movement of the disiloxane compound is promoted.
- the first discharge member 100 be installed in an upper portion of the liquid in the first reaction tank.
- the liquid taken out from the upper part of the first reaction tank 300 is allowed to flow through the first nozzle 1 in the lower part of the liquid in the first reaction tank 300. It can also be performed by discharging vertically from the first discharge member 100 provided. Thus, the liquid is taken out from the upper part of the first reaction tank 300, and the taken-out liquid is discharged vertically upward in the lower part of the liquid in the first reaction tank 300, thereby mixing in the vertical direction. Can be promoted. Further, since the specific gravity of the disiloxane compound is smaller than that of water, water-soluble fluorine ions tend to be present in a relatively large portion in the lower part of the liquid in the first reaction tank 300.
- the discharge flow is water-soluble fluorine ions.
- the suction flow from the side containing a relatively large amount can be sucked.
- a vertically upward jet flow with a suction flow having a relatively large fluorine ion content is provided, thereby promoting the vertical movement of the fluorine ions.
- the first discharge member 100 may be installed in a lower part of the liquid in the first reaction tank.
- the flow 31 can be represented by a 180 ° rotation of FIG.
- the first The discharge member 100 is arranged so that the tip 13 of the first nozzle 1 is located in the organic component.
- the liquid in the first reaction tank 300 is considered to phase-separate into an upper organic phase and a lower aqueous phase.
- such virtual phase separation is performed by the liquid in the first reaction tank 300 on the entire volume (51) of the aqueous component contained in the liquid in the first reaction tank 300.
- the first discharge member is preferably arranged so that the tip 13 of the first nozzle 1 is located in the organic component 41 when such a model is assumed. Since disiloxane compounds have a specific gravity smaller than that of water, they tend to be present in a relatively large amount in the region occupied by this virtual organic component 41. Accordingly, when the first discharge member 100 is arranged so that the tip 13 of the first nozzle 1 is positioned in the virtual organic component 41, the discharge is discharged vertically downward from the tip 13 of the nozzle 1.
- the flow (indicated by reference numeral 3 in FIG.
- the vertical mixing in the reaction step is performed so that the liquid taken out from the lower part of the aqueous component 51 is placed so that the tip 13 of the first nozzle 1 is located in the organic component 41. It is preferable that the discharge is performed by discharging vertically from the arranged first discharge member 100.
- the taken-out liquid contains a relatively large amount of an aqueous component having a specific gravity higher than that of the organic component. Water-soluble fluorine ions are mainly present in the aqueous component.
- the first nozzle 1 is provided in the lower part of the liquid in the first reaction tank 300 for the vertical mixing in the reaction step, the liquid taken out from the upper part of the first reaction tank 300.
- the first discharge member 100 has an aqueous tip 13 of the first nozzle 1 as shown in FIG. You may arrange
- Water-soluble fluorine ions tend to be present in a relatively large amount in the region occupied by the virtual aqueous component 51.
- the discharge flow discharged vertically from the tip 13 of the nozzle 1 is The suction flow from the side having a relatively large fluorine ion content can be sucked.
- a vertically upward jet flow with a suction flow having a relatively large fluorine ion content is provided, thereby promoting the vertical movement of the fluorine ions. In this way, effective mixing in the vertical direction can be achieved.
- the liquid taken out from the upper portion of the organic component 41 is removed from the first discharge member 100. It is preferable to discharge vertically upward.
- the taken-out liquid contains a relatively large amount of the organic component.
- a discharge flow containing a relatively large amount of the organic component is discharged vertically from the tip 13 of the first nozzle 1 located in the virtual aqueous component 51, whereby the disiloxane compound in the organic component In the vertical direction can be more effectively performed.
- the fluorine-containing aqueous solution and the disiloxane compound charged into the first reaction tank 300 are the organic phase containing the upper disiloxane compound and the lower water before the start of mixing.
- Phase separate into phases.
- the virtual organic component 41 described above corresponds to the organic phase before the start of mixing
- the virtual aqueous component 51 corresponds to the aqueous phase before the start of mixing.
- the organic phase containing the disiloxane compound can be moved in the vertical direction. This facilitates vertical mixing more effectively.
- the vertical movement of fluorine ions in the aqueous phase is promoted, and the vertical direction Mixing can be performed more effectively.
- the first nozzle 1 is provided in the lower part of the liquid in the first reaction tank 300 for the vertical mixing in the reaction step, the liquid taken out from the upper part of the first reaction tank 300.
- the first nozzle 1 is positioned so that the tip 13 of the first nozzle 1 is positioned in the aqueous phase before the start of mixing.
- the ejection member 100 may be disposed, and the extraction position of the liquid ejected from the first ejection member 100 may be set above the organic phase before the start of mixing. Also with such a configuration, the liquid in the first reaction tank 300 can be effectively mixed in the vertical direction.
- the first discharge member 100 further includes a first diffuser 2 attached to the tip 13 of the first nozzle 1.
- FIG. 3B schematically shows an example of the first discharge member 100 including the first nozzle 1 and the first diffuser 2.
- the first diffuser 2 has one or more openings 21 on the side of the tip 13 of the first nozzle 1.
- the inner diameter at the tip 23 of the diffuser 2 is usually larger than the inner diameter at the end 22 on the opening side of the diffuser 2.
- the diffuser 2 When the diffuser 2 includes the opening 21, the liquid existing around the discharge member 100 can be efficiently sucked from the opening 21 as a suction flow 31 over a wide range. As a result, the flow rate of the jet flow 32 from the tip 23 of the diffuser 2 increases, and the liquid in the first reaction tank 300 can be mixed more effectively in the vertical direction.
- the flow rate of the suction flow 31 from the side of the discharge flow 3 is preferably 3 to 5 times that of the discharge flow 3. Thereby, the flow volume of the jet flow 32 from the front-end
- FIG. 4 shows an example of the arrangement of the first discharge member 100.
- the liquid in the first reaction tank 300 is phase-separated into an upper organic phase and a lower aqueous phase. To do.
- the total volume of the organic component 41 contained in the liquid in the first reaction tank is positioned on the whole volume of the aqueous component 51 contained in the liquid in the first reaction tank.
- the jet stream 32 to which the suction flow 31 that can contain a large amount of the disiloxane compound is jetted vertically downward from the tip 23 of the first diffuser 2 toward the aqueous component 51, thereby causing the vertical direction of the disiloxane compound. Is further promoted, and vertical mixing can be performed more effectively.
- the first discharge member 100 including the first nozzle 1 and the first diffuser 2 has the tip 13 of the first nozzle 1 in the aqueous component 51. Preferably it is located.
- FIG. 5 shows an example of the arrangement of the first discharge member 100.
- a relatively large amount of water-soluble fluorine ions tends to exist. Therefore, when the tip 13 of the first nozzle 1 is positioned in the virtual aqueous component 51, the suction flow 31 from the side where the fluorine ion content is relatively large is caused to flow into the opening of the first diffuser 2. 21 can inhale.
- the jet flow 32 to which the suction flow 31 having a relatively large fluorine ion content is added is jetted vertically upward from the tip 23 of the first diffuser 2 toward the organic component 41, whereby the vertical flow of the fluorine ions.
- Directional movement is further promoted, and vertical mixing can be performed more effectively.
- the vertical mixing in the reaction process is promoted as the linear velocity of the discharge flow at the tip 13 of the first nozzle 1 increases.
- the linear velocity of the discharge flow can be controlled by the inner diameter of the tip 13 of the first nozzle 1 and the flow rate (or discharge pressure) of the discharge flow.
- the linear velocity of the discharge flow at the tip 13 of the first nozzle 1 is preferably 500 to 2000 m / min. When the linear velocity of the discharge flow is 500 m / min or more, vertical mixing can be performed more effectively. When the linear velocity of the discharge flow is 2000 m / min or less, mixing can be performed at a discharge pressure that does not require special pressure resistance specifications for the nozzle, and the equipment cost can be reduced.
- the first nozzle 1 may be used alone, and a plurality of first nozzles 1 may be installed in the first reaction tank 300. By using the plurality of first nozzles 1, it is possible to achieve a high linear velocity as a whole while reducing the linear velocity per nozzle.
- the inner diameter and discharge pressure at the tip (discharge port) of the nozzle can be set as appropriate so that the above-described linear velocity is achieved.
- the inner diameter at the tip of the nozzle is preferably 1.5 mm to 20 mm. When the inner diameter is 1.5 mm or more, mixing in the vertical direction can be effectively achieved. When the inner diameter is 20 mm or less, mixing can be performed at a discharge pressure that does not require special pressure resistance specifications for the nozzle, and the equipment cost can be reduced.
- the discharge pressure is preferably 0.05 to 0.8 MPa. When the discharge pressure is 0.05 MPa or more, mixing in the vertical direction can be effectively achieved. When the discharge pressure is 0.8 MPa or less, it is not necessary to apply a special pressure resistance specification to the nozzle, and the equipment cost can be suppressed.
- reaction process is carried out in a continuous manner, but the reaction process in the present invention can be carried out either in a batch manner or a continuous manner.
- the first tubular reactor 9 is provided in the ultrasonic generator 91.
- the ultrasonic generator 91 includes a vibrator 92 disposed below the first tubular reactor along the flow direction in the first tubular reactor.
- the ultrasonic generator 91 is filled with a medium such as pure water.
- the disiloxane compound (7) and the fluorine-containing aqueous solution (8) are continuously supplied to the tubular reactor 9 provided in the ultrasonic generator 91 via the conduit 6 and the pump 61.
- the ultrasonic wave emitted from the vibrator 92 is irradiated to the fluorine-containing aqueous solution and the disiloxane compound flowing in the first tubular reactor 9 through the medium.
- the ultrasonic waves are irradiated perpendicular to the direction of flow in the first tubular reactor.
- At least a part of the fluorine-containing aqueous solution and the disiloxane compound in the first tubular reactor 9 are caused by vibrations generated by ultrasonic waves and shock waves (shock waves caused by cavitation) generated by bursting bubbles generated by the ultrasonic waves. It becomes a fine droplet. Such droplets move in the first tubular reactor 9 by the action of ultrasonic vibration or convection, thereby causing vertical mixing.
- the vibrator 92 is preferably arranged so as not to come into contact with the liquid in the first tubular reactor 9.
- the vibrator 92 vibrates depending on the composition of the liquid.
- the child 92 may be consumed.
- the vibrator 92 is arranged so as to come into contact with the liquid in the first tubular reactor 9
- the ultrasonic wave oscillated from the vibrator 92 is reflected on the tube wall of the first tubular reactor 9. This causes resonance.
- the consumption of the vibrator 92 is also promoted by this resonance effect.
- the frequency of the ultrasonic wave irradiated by the vibrator 92 is preferably set to 20 kHz to 1 MHz. When the frequency is 20 kHz or more, mixing by ultrasonic irradiation can be performed more effectively. When the frequency is 1 MHz or less, the attenuation of the ultrasonic wave is small, and the reach distance of the ultrasonic wave can be made sufficiently long.
- Such a mixing method using the tubular reactor 9 and the ultrasonic generator 91 also has an advantage that the mixing and reaction of the fluorine-containing aqueous solution and the disiloxane compound can be performed in a single pass.
- mixing by ultrasonic irradiation is not limited to the embodiment shown in FIG. In the embodiment shown in FIG. 6, the reaction step is carried out continuously, but mixing by ultrasonic irradiation can also be carried out batchwise.
- the vertical mixing in the reaction step can be performed by a countercurrent contact method.
- the mixing by the counter-current contact method is a first counter-current reaction tower, in which a fluorine-containing aqueous solution is supplied to the upper part of the first counter-current reaction tower, and the disiloxane compound is converted into the first counter-current reaction tower.
- An organic phase containing a disiloxane compound and a monofluorosilane compound is obtained at the top of the first counter-current reaction tower, and is supplied to the bottom of the first counter-current reaction tower, rather than a fluorine-containing aqueous solution at the bottom of the first counter-current reaction tower.
- the mixing by the countercurrent contact method is performed in the first countercurrent reactor 10 filled with the packing material.
- the filler that can be used in the present embodiment is not particularly limited, and fillers such as Raschig rings and demisters can be appropriately used.
- the fluorine-containing aqueous solution 8 is supplied to the upper part of the first countercurrent reaction tower 10 via the conduit 6 and the pump 61.
- the disiloxane compound 7 is supplied to the lower part of the first countercurrent reaction tower 10 via the conduit 6 and the pump 61.
- the supply amount and residence time of the fluorine-containing aqueous solution 8 and the disiloxane compound 7 can be appropriately set according to the apparatus used. Since the specific gravity of the disiloxane compound is smaller than that of water, the fluorine-containing aqueous solution supplied in the upper part of the reaction tower 10 moves downward in the reaction tower 10 by the action of gravity, while being supplied in the lower part of the reaction tower 10. The disiloxane compound moves upward in the reaction column 10. By such vertical movement of both the disiloxane compound and the fluorine-containing aqueous solution, the chance of contact between the fluorine ion in the fluorine-containing aqueous solution and the disiloxane compound is increased, and the reaction can be effectively advanced.
- the first counterflow is provided with an agitator that vibrates up and down instead of the first countercurrent reaction tower 10 filled with the above-mentioned packing.
- a flow reactor In this embodiment, the fluorine-containing aqueous solution is supplied to the upper part of the reaction tower, and the disiloxane compound is supplied to the lower part of the reaction tower.
- the stirrer may be, for example, a large number of perforated plates attached in the reaction tower. When the perforated plate vibrates up and down, the liquid in the reaction tower is vibrated up and down.
- Directional mixing can be achieved.
- a 1st countercurrent type reaction tower which equips the inside with the stirrer which vibrates up and down
- a reciprocating type extraction tower, a continuous liquid-liquid extraction apparatus etc. can be used, for example.
- the reaction step in the present invention has the advantage that no additional operation for adjusting the pH of the liquid to be treated is required.
- the reaction represented by the above formula (I) is activated by protons, the progress of the reaction can be promoted under acidic conditions. Therefore, the fluorine-containing aqueous solution is preferably an acidic aqueous solution.
- the fluorine-containing aqueous solution that can be treated by the treatment method of the present invention is not particularly limited as described above, and the method of the present invention can be applied to the treatment of various aqueous solutions containing fluorine.
- the fluorine-containing aqueous solution may be, for example, fluorine-containing hydrochloric acid, fluorine-containing sulfuric acid, and a mixture thereof.
- the method of the present invention is surprisingly capable of selectively removing fluorine ions by selectively reacting fluorine ions with a disiloxane compound even in an aqueous solution containing a large amount of chlorine ions such as fluorine-containing hydrochloric acid. Bring effect.
- the method of the present invention can treat an aqueous solution without changing the acid concentration before and after the reaction step when treating an acidic fluorine-containing aqueous solution such as fluorine-containing hydrochloric acid.
- an acidic fluorine-containing aqueous solution such as fluorine-containing hydrochloric acid.
- the acid concentration (hydrogen chloride concentration) in hydrochloric acid does not substantially change before and after the reaction step.
- the reaction step in the present invention can be carried out at any value of the acid concentration, and has an advantage that an additional operation for adjusting the acid concentration is not required.
- the acid concentration of the fluorine-containing aqueous solution is 0.1% by weight or more because the reaction represented by the formula (I) can be further promoted.
- the acid concentration of the fluorine-containing aqueous solution is more preferably 10 to 40% by weight.
- H + is considered to have a catalytic effect. Therefore, the effect is expected to increase as the amount of H + present increases, that is, as the acid concentration increases.
- the reaction represented by the formula (I) can be further promoted.
- the acid concentration exceeds 40% by weight, the catalytic effect of H + becomes almost constant without depending on the acid concentration. Therefore, when the acid concentration is 40% by weight or less, it is possible to reduce the amount of acid necessary for adjusting the acid concentration while achieving a sufficient catalytic effect.
- the reaction step in the present invention can be carried out at room temperature, and has the advantage of not requiring costly temperature adjustment. However, it is preferable to perform the reaction step at a temperature of 50 ° C. or higher because the reaction represented by the above formula (I) can be further promoted. It is also possible to further advance the reaction of formula (I) by carrying out the reaction step under pressurized conditions.
- the disiloxane compound is a reactant for reacting with fluorine ions in the fluorine-containing aqueous solution to produce a monofluorosilane compound, and for extracting the produced monofluorosilane compound from the aqueous phase. It is also a solvent.
- the disiloxane compound as the reactant may be used in an amount of at least 0.5 molar equivalents relative to the fluorine ions in the fluorine-containing aqueous solution.
- the molar ratio of the disiloxane compound used in the reaction step to the fluorine ions in the fluorine-containing aqueous solution is preferably 0.5 to 20.
- the molar ratio is 0.5 or more, a disiloxane compound having a stoichiometric amount or more with respect to fluorine ions present in the fluorine-containing aqueous solution is present, and the reaction of the formula (I) can proceed. it can.
- the treatment amount of the fluorine-containing aqueous solution in the reaction step can be set to a practically sufficient amount, and high treatment efficiency can be achieved.
- the method of the present invention optionally includes a first separation step.
- the first separation step is a step of separating the first reaction liquid obtained in the reaction step into an organic phase and an aqueous phase. Since the monofluorosilane compound and unreacted disiloxane compound produced in the reaction step are insoluble in water, the organic phase contains the disiloxane compound and the monofluorosilane compound, and the aqueous phase contains the disiloxane compound and the monofluorosilane compound. Is substantially not included.
- the aqueous phase can be obtained as a purified aqueous solution having a fluorine concentration lower than that of the fluorine-containing aqueous solution.
- separation process is unnecessary.
- the first separation step is performed in the first separation tank 400 shown in FIG.
- a 1st separation process can be implemented by a continuous type as shown in FIG. 2, it can also be implemented by a batch type.
- the first reaction tank 300 can be used as the first separation tank 400. That is, the first separation step can be performed by performing the reaction step in the first reaction vessel 300, and then stopping the mixing and allowing the liquid in the first reaction vessel 300 to stand for phase separation. it can.
- the upper organic phase 4 contains a disiloxane compound and a monofluorosilane compound.
- the lower aqueous phase 5 is substantially free of disiloxane compounds and monofluorosilane compounds. In the present specification, “substantially free” of one compound means that the content of the compound is 300 ppm or less.
- the aqueous phase 5 is obtained as a purified aqueous solution having a fluorine concentration lower than that of the fluorine-containing aqueous solution.
- the fluorine concentration in the purified aqueous solution can be reduced to 1000 ppm or less, preferably 500 ppm or less, more preferably 100 ppm or less.
- the reaction step in the method of the present invention can selectively remove fluorine ions by selectively reacting fluorine ions with a disiloxane compound even in an aqueous solution containing a large amount of chlorine ions.
- a purified aqueous solution such as purified hydrochloric acid can be obtained in the first separation step without changing the acid concentration before and after the reaction step.
- purified hydrochloric acid having an acid concentration substantially the same as the acid concentration (hydrogen chloride concentration) of the fluorine-containing hydrochloric acid before the reaction step can be obtained in the first separation step. it can.
- the method of the present invention optionally further comprises a regeneration step and a second separation step.
- the regeneration step is a step of regenerating the monofluorosilane compound produced by the reaction between the fluorine ion in the fluorine-containing aqueous solution and the disiloxane compound into a disiloxane compound by reacting with a base.
- the monofluorosilane compound contained in the organic phase is obtained by mixing the organic phase obtained in the first separation step (reaction step when the reaction step is performed by a countercurrent contact method) and a basic aqueous solution. Is reacted with a base contained in a basic aqueous solution to obtain a second reaction solution containing a disiloxane compound and a fluoride salt.
- the reaction in the regeneration step is represented by the following formulas (II) and (III-1) to (III-3).
- the monofluorosilane compound produced by the reaction of formula (I) in the reaction step is TMFS.
- TMFS is regenerated into HMDS via trimethylsilanol in the regeneration step.
- the reactions of formulas (II) and (III-1) to (III-3) are compared with the reactions of formula (I) in the reaction step And can proceed easily. Therefore, the mixing in the regeneration step does not have to be performed in the vertical direction, and any mixing method such as mixing using a mixer such as a static mixer can be appropriately employed.
- the reactions of the formulas (II) and (III-1) to (III-3) can be further performed by vertically mixing the organic phase obtained in the first separation step and the basic aqueous solution. Since it can be further promoted, it is preferable to perform vertical mixing.
- the vertical mixing of the organic phase and the basic aqueous solution in the regeneration step is preferably performed in the same manner as the vertical mixing in the reaction step described above.
- the regeneration step can be performed in the second reaction vessel 500 shown in FIG.
- the second reaction vessel 500 includes a conduit 6 and a pump 61.
- the liquid taken out from the second reaction tank 500 is mixed with the liquid in the second reaction tank 500 from the second discharge member 101 provided with the second nozzle 111 in the vertical direction. It is preferable to carry out by discharging. Thereby, the progress of the reactions represented by the formulas (II) and (III-1) to (III-3) can be promoted.
- the liquid taken out from the lower part of the second reaction tank 500 is mixed with the second nozzle 111 provided in the upper part of the liquid in the second reaction tank 500. It is preferable that the discharge is performed by discharging the discharge member 101 vertically downward. By performing the mixing in this way, the vertical mixing of the liquid in the second reaction tank 500 can be further promoted.
- the vertical mixing in the regeneration step can be performed by removing the liquid taken out from the upper part of the second reaction tank 500 from the second nozzle 111 in the lower part of the liquid in the second reaction tank 500. It may be performed by discharging vertically from the second discharge member 101 provided. Even with such a configuration, the liquid in the second reaction tank 500 can be effectively mixed in the vertical direction.
- the second The discharge member 101 is arranged so that the tip of the second nozzle 111 is located in the organic component.
- the liquid in the second reaction tank 500 is considered to phase-separate into an upper organic phase and a lower aqueous phase.
- Such virtual phase separation is similar to the virtual model in the reaction step shown in FIG. 4, and the entire volume of the aqueous component contained in the liquid in the second reaction tank 500 (corresponding to 51 in FIG. 4).
- the total volume of the organic components contained in the liquid in the second reaction tank 500 (corresponding to 41 in FIG. 4) is located on the top.
- the discharge flow discharged vertically downward from the tip of the second nozzle 111 is around it.
- Monofluorosilane compounds in organic components that may be present in large numbers can be sucked in as a suction flow from the side.
- a vertical jet flow with a suction flow that can contain a large amount of the monofluorosilane compound is provided, thereby promoting the vertical movement of the monofluorosilane compound. In this way, effective mixing in the vertical direction can be achieved.
- the vertical mixing in the regeneration process may be performed by discharging the liquid extracted from the lower part of the aqueous component from the second discharge member 101 in the vertical downward direction. preferable. By performing the mixing in such a configuration, the vertical movement of the aqueous component is promoted, and the vertical mixing of the liquid in the second reaction tank 500 can be performed more effectively.
- the second discharge member 101 may further include a second diffuser 211 attached to the tip of the second nozzle 111.
- the second diffuser 211 has one or more openings on the side of the tip of the second nozzle 111.
- the second nozzle 111 and the second diffuser 211 those similar to the first nozzle 1 and the diffuser 2 of the above-described one can be used.
- the vertical mixing in the regeneration process is promoted as the linear velocity of the discharge flow at the tip of the second nozzle 111 increases, similarly to the vertical mixing in the reaction process.
- the linear velocity of the discharge flow at the tip of the second nozzle 111 is preferably 500 to 2000 m / min. When the linear velocity of the discharge flow is 500 m / min or more, vertical mixing can be performed more effectively. When the linear velocity of the discharge flow is 2000 m / min or less, mixing can be performed at a discharge pressure that does not require special pressure resistance specifications for the nozzle, and the equipment cost can be reduced.
- the vertical mixing in the regeneration step is performed by applying ultrasonic waves to the organic phase and the basic aqueous solution obtained in the first separation step (reaction step when the reaction step is performed by a countercurrent contact method). You may carry out by irradiating. Mixing by irradiation with ultrasonic waves in the regeneration step can be performed by the same method as mixing by irradiation with ultrasonic waves in the above-described reaction step.
- the regeneration step may be performed in a second tubular reactor having the same configuration as the first tubular reactor 9 shown in FIG. In the second tubular reactor, ultrasonic waves are radiated by a vibrator arranged below the second tubular reactor along the flow direction in the second tubular reactor.
- the vertical mixing in the regeneration step can be performed by a countercurrent contact method.
- the mixing by the counter-current contact method is the second counter-current reaction tower, and the organic phase obtained in the first counter-current reaction tower or the first separation tank is the lower part of the second counter-current reaction tower.
- the basic aqueous solution is fed to the top of the second countercurrent reactor, and contains an organic compound containing a disiloxane compound and substantially free of fluoride salts at the top of the second countercurrent reactor.
- the mixing by the countercurrent contact method in the regeneration step is a second countercurrent having the same configuration as that of the first countercurrent reaction column filled with packing, which can be used in the countercurrent contact method in the above-described reaction step. It may be carried out in a reaction tower.
- the organic phase obtained in the reaction step or the first separation step is supplied to the lower portion of the second countercurrent reaction column via a conduit and a pump.
- the basic aqueous solution is supplied to the upper part of the second counter-current reaction tower via a conduit and a pump.
- the organic phase Since the organic phase has a lower specific gravity than water, the basic aqueous solution supplied at the top of the reaction tower moves downward in the reaction tower by the action of gravity, while the organic phase supplied at the bottom of the reaction tower is Move upward in the reaction tower.
- the opportunity for contact between the monofluorosilane compound in the organic phase and the basic aqueous solution increases, and the regeneration reaction can proceed effectively.
- an organic phase containing a disiloxane compound and substantially free of fluoride salts can be obtained at the top of the second countercurrent reaction tower, while the reaction tower An aqueous phase containing a fluoride salt and substantially free of disiloxane compounds can be obtained at the bottom.
- the organic layer thus obtained can be reused in the reaction step.
- the second countercurrent flow is provided with an agitator that vibrates up and down instead of the second countercurrent reaction column filled with the above-mentioned packing.
- a reaction tower As a 2nd countercurrent type reaction tower which equips the inside with the stirrer which vibrates up and down, the thing similar to the 1st countercurrent type reaction tower which equips the inside with the stirrer which can be vibrated up and down which can be used at a reaction process should be used. Can do.
- the fluorine-containing aqueous solution is supplied to the upper part of the reaction tower, and the disiloxane compound is supplied to the lower part of the reaction tower.
- the amount of the base contained in the basic aqueous solution used in the regeneration step is at least relative to the amount of the monofluorosilane compound contained in the organic phase obtained in the first separation step. What is necessary is just 1 molar equivalent.
- the molar ratio of the base contained in the basic aqueous solution used in the regeneration step to the monofluorosilane compound contained in the organic phase obtained in the first separation step is preferably 1.3 or more, more preferably 1.5 or more. It is. When the molar ratio is 1.3 or more, the progress of the reactions of the formulas (II) and (III-1) to (III-3) can be promoted. When the molar ratio is 1.5 or more, the reaction rate between the monofluorosilane compound and the base can be close to 100%.
- the pH of the basic aqueous solution is preferably 8 or more, more preferably 13-14.
- the pH of the basic aqueous solution is within the above range, the progress of the reactions of formulas (II) and (III-1) to (III-3) can be promoted.
- the basic aqueous solution include a lithium hydroxide aqueous solution, a potassium hydroxide aqueous solution, a sodium hydroxide aqueous solution, a calcium hydroxide aqueous solution, a magnesium hydroxide aqueous solution, and a mixture thereof.
- the monofluorosilane compound reacts with the OH ⁇ ion in the basic aqueous solution to regenerate the disiloxane compound.
- the dissociated fluorine ions generate alkali metal ions and / or alkaline earth metal ions and metal salts (for example, LiF, KF, NaF, CaF 2 , MgF 2, etc.) contained in the basic aqueous solution.
- metal salts for example, LiF, KF, NaF, CaF 2 , MgF 2, etc.
- the solubility of the metal salt (NaF) produced in the regeneration step is relatively high among the above-mentioned metal salts, so that the insoluble metal salt in the regeneration step and the second separation step Precipitation can be prevented.
- running cost can be suppressed by using sodium hydroxide aqueous solution. Therefore, it is preferable to use an aqueous sodium hydroxide solution as the basic aqueous solution.
- the regeneration process is carried out in a continuous manner, but the regeneration process in the present invention can also be carried out in a batch manner.
- the regeneration process may be carried out continuously using the configuration shown in FIG. 6 as described above.
- mixing by ultrasonic irradiation can also be performed in a batch manner.
- the second reaction liquid obtained in the regeneration step is substantially divided into an organic phase containing a disiloxane compound and substantially free of a fluoride salt, and containing a fluoride salt and substantially containing a disiloxane compound. It is the process for carrying out phase separation to the water phase which is not contained in. In addition, when mixing in a regeneration process is performed by a countercurrent contact method, a 2nd separation process is unnecessary.
- the second separation step is performed in the second separation tank 600 shown in FIG.
- the second separation step can be carried out continuously as shown in FIG. 2, but can also be carried out batchwise.
- the second reaction tank 500 can be used as the second separation tank 600. That is, the regeneration process is performed in the second reaction tank 500, and then the second separation process is performed by stopping mixing and allowing the liquid in the second reaction tank 500 to stand and phase-separate. it can.
- the upper organic phase 4 contains a disiloxane compound and is substantially free of fluoride salts.
- the lower aqueous phase 5 contains a fluoride salt and is substantially free of disiloxane compounds.
- the fluoride salt is NaF.
- the aqueous phase 5 is recovered as a fluoride salt-containing liquid.
- the organic phase 4 obtained in the second separation step can be reused in the reaction step as a disiloxane compound.
- the organic phase 4 obtained in the second separation tank 600 can be reused in the first reaction tank 300 as a disiloxane compound.
- the disiloxane compound can be regenerated and reused, so that the processing cost can be reduced.
- reaction step Since the reaction step, the first separation step, the regeneration step and the second separation step in the method of the present invention are not accompanied by a substantial increase in temperature and pressure, normal temperature and normal pressure without controlling the temperature and pressure. Can be implemented.
- Tests 1 to 5 [Example 1. Dependence of time required for reaction process on mixing method] In Tests 1 to 5 below, the time required for the reaction process of the present application was examined using various mixing methods. Tests 1 to 5 were all performed at room temperature.
- Test 1 was conducted using a reaction tank with a capacity of 1 L.
- the reaction vessel includes a conduit and a pump for taking out the liquid in the reaction vessel and returning it to the reaction vessel.
- Hydrogen concentration 13 wt% chloride, fluorine concentration fluorine-containing hydrochloric acid (density 1.07 g / cm 3) of 2100 ppm 0.75 L (0.80 kg) and hexamethyldisiloxane (HMDS, density 0.764g / cm 3) 0.10L (0.076 kg) was placed in a reaction vessel and separated into two phases.
- the tip of the conduit was placed in the organic phase containing the upper HMDS.
- the inner diameter of the tip of the conduit was 4.37 mm.
- the liquid taken out from below the reaction tank was returned to the reaction tank through a conduit and a pump, thereby mixing the liquid in the reaction tank.
- the flow rate of the liquid discharged from the conduit was set to 20 L / min.
- the liquid in the reaction vessel was in a uniformly mixed state without phase separation. During mixing, the liquid in the reaction vessel was sampled over time. When the sampled liquid was allowed to stand, phase separation occurred quickly. The fluorine concentration in the lower aqueous phase was measured with a fluorine ion meter.
- Test 2 was performed using a reaction tank with a capacity of 5 L.
- the reaction vessel includes a conduit and a pump for taking out the liquid in the reaction vessel and returning it to the reaction vessel.
- the inner diameter of the tip of the conduit was 4.37 mm.
- Flow rate of liquid discharged from a conduit using 3.75 L (4.01 kg) of fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 13% by weight and a fluorine concentration of 2518 ppm and hexamethyldisiloxane (HMDS) 0.51 L (0.39 kg) Test 2 was performed in the same procedure as Test 1 except that was set to 1.43 L / min. During mixing, the liquid in the reaction vessel was uniformly mixed without phase separation.
- Test 3 was performed using a reaction tank having a capacity of 13 L.
- the reaction vessel includes a conduit and a pump for taking out the liquid in the reaction vessel and returning it to the reaction vessel.
- a discharge member was attached to the end of the conduit.
- the discharge member has a nozzle and a diffuser attached to the tip of the nozzle, and the diffuser has a plurality of openings on the side of the tip of the nozzle.
- the inner diameter of the nozzle tip was 1.5 mm.
- the liquid in the reaction vessel was sampled over time. When the sampled liquid was allowed to stand, the phases were quickly separated. The fluorine concentration in the lower aqueous phase was measured with a fluorine ion meter. Further, the HCl concentration in the aqueous phase at the end of mixing was measured by a titration method.
- Test 4 was performed using the same reaction tank as used in Test 3.
- the reaction vessel includes a conduit and a pump for taking out the liquid in the reaction vessel and returning it to the reaction vessel.
- a discharge member was attached to the end of the conduit.
- the discharge member has a nozzle and a diffuser attached to the tip of the nozzle, and the diffuser has a plurality of openings on the side of the tip of the nozzle.
- the inner diameter of the nozzle tip was 1.5 mm.
- Test 4 Liquid discharged from the tip of the nozzle using 9.7 L (10.3 kg) of fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 13 wt% and a fluorine concentration of 1829 ppm and hexamethyldisiloxane (HMDS) 1.51 L (1.15 kg) Test 4 was performed in the same procedure as Test 3 except that the flow rate of was set to 1.4 L / min. The liquid in the reaction vessel was in a uniformly mixed state without phase separation.
- HMDS hexamethyldisiloxane
- Table 1 shows the results of calculating the linear velocity of the discharge flow at the tip of the conduit for Tests 1 and 2, and the results of calculating the linear velocity of the discharge flow at the tip of the nozzle of the discharge member for Tests 3 and 4. From Table 1, it can be seen that as the linear velocity increases, the decrease rate of the fluorine concentration increases. This is considered to be due to the fact that the higher the linear velocity, the more effectively the mixing in the vertical direction is performed, and the progress of the reaction of the above formula (I) is promoted.
- the result of Test 5 is shown in FIG.
- the fluorine concentration after 20 minutes from the start of mixing was 1739 ppm
- the fluorine concentration after 90 minutes was 613 ppm
- a fluorine concentration of 100 ppm or less could not be achieved.
- Example 2. Ultrasonic mixing In the following tests 6 to 8, the reaction process was performed using the ultrasonic generator 91 including the tubular reactor 9 and the vibrator 92 shown in FIG.
- the tubular reactor 9 had an inner diameter of 1/8 inch (0.32 cm) and a total length of 20 m.
- the tubular reactor 9 was provided in the ultrasonic generator 91 and filled with pure water as a medium.
- the temperature in the tubular reactor 9 was set to 35 ° C.
- the output of the ultrasonic generator 91 was set to 400 W, and the frequency of the vibrator 92 was set to 38 kHz.
- Test 6 100.91 g of fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 14% by weight and a fluorine concentration of 2136 ppm and 16.98 g of HMDS were continuously supplied to the tubular reactor 9 using the pump 61.
- the residence time (that is, the ultrasonic wave irradiation time) was set to 13.6 minutes.
- the fluorine concentration in the lower aqueous phase was measured with a fluorine ion meter.
- Test 7 was performed in the same procedure as Test 6, except that the amount of fluorine-containing hydrochloric acid used was 292.38 g, the amount of HMDS used was 18.00 g, and the residence time was 5.45 minutes.
- Test 8 was performed in the same procedure as Test 6 except that the amount of fluorine-containing hydrochloric acid used was 384.15 g, the amount of HMDS used was 97.85 g, and the residence time was 1.63 minutes.
- the results of tests 6 to 8 are shown in Table 2 and FIG.
- the vertical axis represents the fluorine concentration in the aqueous phase
- the horizontal axis represents the residence time (that is, the irradiation time).
- the fluorine concentration in the aqueous phase at a residence time of 1.63 minutes was 16.9 ppm, and a fluorine concentration of 100 ppm or less could be achieved at a residence time of 1.63 minutes or more.
- Test 9 was performed in the same procedure as Test 5 except that the temperature during mixing was set to 50 ° C. During mixing, the liquid in the reaction vessel remained phase separated.
- Test 10 was performed in the same procedure as Test 5 except that the temperature during mixing was set to 80 ° C. During mixing, the liquid in the reaction vessel remained phase separated.
- FIG. 9 indicates that the higher the temperature in the reaction step, the shorter the time required for the reaction.
- the reaction temperature was 80 ° C. (Test 10)
- a fluorine concentration of 100 ppm or less was achieved in the aqueous phase 20 minutes after the start of mixing.
- the reaction temperature was room temperature (Test 5)
- Test 5 room temperature
- Test 11 was conducted in the same procedure as in Test 5 except that fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 0% by weight and a fluorine concentration of 1976 ppm was used.
- Test 12 was performed in the same procedure as Test 5 except that fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 20.3% by weight and a fluorine concentration of 2100 ppm was used.
- Test 13 was conducted in the same procedure as in Test 5 except that fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 24.6% by weight and a fluorine concentration of 2000 ppm was used.
- Test 14 was conducted in the same procedure as Test 5 except that fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 28.7% by weight and a fluorine concentration of 1800 ppm was used.
- the results of tests 5 and 11-14 are shown in FIG.
- the vertical axis represents the fluorine removal rate after 5 minutes from the start of mixing
- the horizontal axis represents the hydrogen chloride concentration in the fluorine-containing hydrochloric acid.
- Example 5 The reaction step was performed in the same procedure as in Test 3. Mixing was stopped 10 minutes after the start of mixing. The fluorine concentration in the aqueous phase when mixing was stopped was 14 ppm. The liquid in the reaction vessel was separated into two phases immediately after mixing was stopped. The liquid in the reaction vessel was allowed to stand, and the upper organic phase and the lower aqueous phase were sampled over time. The HMDS concentration and tetramethylfluorosilane (TMFS) concentration in the sampled aqueous phase were measured by gas chromatography, and the hydrogen chloride concentration in the sampled organic phase was measured by ion chromatography. 120 minutes after mixing was stopped, the organic and aqueous phases were collected separately.
- TMFS tetramethylfluorosilane
- “standing time” means the time from the time when mixing is stopped.
- the TMFS concentration in the aqueous phase is 10 ppm or less when mixing is stopped, and it can be seen that the fluorine compound in the aqueous phase was removed by the reaction step.
- the concentration of hydrogen chloride in the organic phase decreased to 20 ppm or less within 30 minutes.
- the HMDS concentration in the aqueous phase decreased to 300 ppm or less within 30 minutes. From the above results, it was found that the first separation process can be completed in about 30 minutes after mixing is stopped.
- TMFS concentration in the organic phase recovered in Test 15 was measured by gas chromatography and found to be 6.2% by weight.
- This organic phase 1.764 L (1.348 kg) containing TMFS and HMDS and 2.794 L (2.934 kg) of a 5 wt% aqueous sodium hydroxide (NaOH) solution as a basic aqueous solution were placed in a 5 L reactor. I put it in.
- the reaction tank includes a conduit and a pump for taking out the liquid in the reaction tank and returning it to the reaction tank, and a discharge member including a nozzle and a diffuser is attached to the tip of the conduit.
- the inner diameter of the nozzle tip was 1.5 mm.
- the discharge member was installed so that the opening of the diffuser was positioned in the upper organic phase.
- the liquid taken out from below the reaction tank was returned to the reaction tank through a conduit and a pump, thereby mixing the liquid in the reaction tank.
- the flow rate of the liquid discharged from the tip of the nozzle was set to 1.4 L / min.
- the linear velocity of the discharge flow at the tip of the second nozzle 111 was 792 m / min.
- the liquid in the reaction vessel was in a uniformly mixed state without phase separation. During mixing, the liquid in the reaction vessel was sampled over time. When the sampled liquid was allowed to stand, the phases were quickly separated.
- the TMFS concentration in the upper organic phase was measured by gas chromatography. The results are shown in Table 4 and FIG. After 6 minutes from the start of mixing, the TMFS concentration in the organic phase was not detected (less than 0.1 ppm). From this, it can be seen that TMFS was almost regenerated to HMDS within 6 minutes from the start of mixing.
- Test 18 was performed in the same procedure as Test 17 except that the amount of the HMDS solution was 30.01 g and the amount of the aqueous NaOH solution was 4.61 g. The molar ratio of NaOH to TMFS contained in the HMDS solution was 0.5. After completion of the test, the pH of the aqueous phase and the TMFS concentration in the organic phase were measured.
- Test 19 was performed in the same procedure as Test 17 except that the amount of the HMDS solution was 29.98 g and the amount of the aqueous NaOH solution was 9.21 g. The molar ratio of NaOH to TMFS contained in the HMDS solution was 1.0. After completion of the test, the pH of the aqueous phase and the TMFS concentration in the organic phase were measured.
- Test 20 was performed in the same procedure as Test 17, except that the amount of the HMDS solution was 30.00 g and the amount of the aqueous NaOH solution was 11.98 g. The molar ratio of NaOH to TMFS contained in the HMDS solution was 1.3. After completion of the test, the pH of the aqueous phase and the TMFS concentration in the organic phase were measured.
- Test 21 was performed in the same procedure as Test 17 except that the amount of the HMDS solution was 19.96 g and the amount of the aqueous NaOH solution was 9.34 g. The molar ratio of NaOH to TMFS contained in the HMDS solution was 1.5. After completion of the test, the pH of the aqueous phase and the TMFS concentration in the organic phase were measured.
- Test 22 was performed in the same procedure as Test 17, except that the amount of the HMDS solution was 20.01 g and the amount of the aqueous NaOH solution was 11.21 g. The molar ratio of NaOH to TMFS contained in the HMDS solution was 1.8. After completion of the test, the pH of the aqueous phase and the TMFS concentration in the organic phase were measured.
- HMDS regeneration rate ⁇ (weight of TMFS present in HMDS solution before mixing) ⁇ (weight of TMFS remaining in organic phase after mixing) ⁇ / (present in HMDS solution before mixing) TMFS weight) x 100 From Table 5 and FIG. 15, it can be seen that when the molar ratio of NaOH to TMFS was 1.3 or more, a HMDS regeneration rate of 99% or more was achieved at a mixing time of 15 minutes.
- Example 8. Reproduction process using static mixer In the following tests 23 to 27, the regeneration process was performed using a static mixer. Tests 23 to 27 were all performed using a static mixer having an inner diameter of 9.52 mm and an overall length of 180 mm at room temperature.
- Test 23 an organic phase containing TMFS and HMDS and a 5 wt% NaOH aqueous solution were continuously supplied to a static mixer.
- the supply flow rate of the organic phase was 1.179 L / min
- the supply flow rate of the NaOH aqueous solution was 0.166 L / min
- the flow rate of the liquid (total of the organic phase and the NaOH aqueous solution) at the inlet of the static mixer was 0.315 m / s. .
- the liquid was sampled over time at the exit of the static mixer. When the sampled liquid was allowed to stand, the phases were quickly separated.
- the TMFS concentration in the upper organic phase was measured by gas chromatography.
- Test 24 Other than setting the supply flow rate of the organic phase to 0.236 L / min, the supply flow rate of the NaOH aqueous solution to 0.196 L / min, and the flow rate of the liquid (total of the organic phase and the NaOH aqueous solution) at the static mixer inlet to 0.101 m / s The test 24 was conducted in the same procedure as the test 23.
- Test 25 Other than setting the supply flow rate of the organic phase to 0.236 L / min, the supply flow rate of the NaOH aqueous solution to 0.0646 L / min, and the flow rate of the liquid (total of the organic phase and the NaOH aqueous solution) at the inlet of the static mixer to 0.07 m / s
- the test 25 was performed in the same procedure as the test 23.
- Test 26 Other than setting the supply flow rate of the organic phase to 0.236 L / min, the supply flow rate of the NaOH aqueous solution to 0.238 L / min, and the flow rate of the liquid (total of the organic phase and the NaOH aqueous solution) at the static mixer inlet to 0.10 m / s The test 26 was conducted in the same procedure as the test 23.
- Test 27 The flow rate of the organic phase was 1.179 L / min, the NaOH aqueous solution was 0.238 L / min, and the liquid flow rate at the inlet of the static mixer (the total of the organic phase and the NaOH aqueous solution) was 0.33 m / s.
- the test 27 was conducted in the same procedure as the test 23.
- FIG. 16 is a plot of the HMDS regeneration rate at the end of each test versus the flow rate. It can be seen from Table 6 and FIG. 16 that the higher the liquid flow rate at the static mixer inlet, that is, the higher the Reynolds number (Re), the higher the HMDS regeneration rate. In Tests 23 and 27, where the Reynolds number was about 2300 or more, that is, the liquid flow in the static mixer was turbulent, an HMDS regeneration rate of 95% or more could be achieved. This is considered to be due to the fact that the mixing property of the organic phase and the NaOH aqueous solution is increased due to the turbulent flow of the liquid in the static mixer.
- Example 9 Second separation step
- Test 28 The regeneration process was performed in the same procedure as in Test 16. Mixing was stopped 10 minutes after the start of mixing. The TMFS concentration in the organic phase when mixing was stopped was not detected (less than 0.1 ppm). The liquid in the reaction vessel was separated into two phases immediately after mixing was stopped. After stopping mixing, the lower aqueous phase was sampled over time. The HMDS concentration in the sampled aqueous phase was measured by gas chromatography. 120 minutes after mixing was stopped, the organic and aqueous phases were collected separately. The results are shown in Table 7 and FIG. In FIG. 17, “standing time” means the time from the time when mixing is stopped. The HMDS concentration in the aqueous phase dropped to about 300 ppm within 25 minutes. From this result, it was found that the second separation step could be completed in about 25 minutes after mixing was stopped.
- Test 29 1.5 L (1.13 kg) of the organic phase recovered in the test 28, that is, regenerated HMDS, and 9.3 L (9.95 kg) of a fluorine-containing aqueous solution having a hydrogen chloride concentration of 12.8% by weight and a fluorine concentration of 1829 ppm.
- Test 29 was performed in the same procedure as in Test 3, except that it was used.
- the first reaction tank 300 used in the reaction step has a capacity of 5.3 L, and includes a conduit 6 and a pump 61 for taking out the liquid in the reaction tank and returning it to the reaction tank.
- a first discharge member 100 is attached to the tip of the conduit 6.
- the first discharge member 100 includes a first nozzle 1 and a first diffuser 2 attached to the tip of the nozzle 1, and the first diffuser 2 is located on the side of the tip of the first nozzle 1. It has a plurality of openings.
- the inner diameter of the tip of the first nozzle 1 was 1.5 mm.
- First reaction vessel 300 is charged with 3.83 kg (3.58 L) of fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 15.5 wt% and a fluorine concentration of about 1932 ppm, and 0.383 kg (0.50 L) of HMDS, and the reaction process is carried out in a batch manner. went.
- the liquid taken out from below the first reaction tank 300 was returned into the first reaction tank 300 through the conduit 6 and the pump 61, whereby the liquid in the first reaction tank 300 was mixed.
- the flow rate of the liquid discharged from the tip of the first nozzle 1 was set to 2.4 L / min.
- the linear velocity of the discharge flow at the tip of the first nozzle 1 was 1358 m / min.
- the liquid in the first reaction tank 300 was sampled over time. When the sampled liquid was allowed to stand, the phases were quickly separated. The fluorine concentration in the lower aqueous phase was measured with a fluorine ion meter. The fluorine concentrations at 15 minutes and 20 minutes after the start of mixing were 21 ppm and 15 ppm, respectively. From this, when performing a reaction process by a continuous type, it turned out that it is enough if the residence time in the 1st reaction tank 300 is about 15 minutes. After 20 minutes from the start of mixing, the batch-type reaction process was completed. The apparatus was set so that the liquid overflowed from the first reaction tank 300 was supplied to the first separation tank 400, and a continuous reaction process was performed according to the following procedure.
- a fluorine-containing hydrochloric acid having a hydrogen chloride concentration of 15.6% by weight and a fluorine concentration of about 1770 to 1930 ppm and HMDS are continuously supplied to the first reaction tank 300, and the overflowed liquid is supplied to the subsequent first separation tank 400. Supplied to.
- the flow rate of hydrochloric acid was set to about 207 to 264 mL / min, the flow rate of HMDS was set to about 30 to 34 mL / min, and the residence time was set to about 13 to 17 minutes.
- the liquid taken out from below the first reaction tank 300 was returned into the first reaction tank 300 through the conduit 6 and the pump 61, whereby the liquid in the first reaction tank 300 was mixed.
- the flow rate of the liquid discharged from the tip of the first nozzle 1 was set to 2.4 L / min.
- the linear velocity of the discharge flow at the tip of the first nozzle 1 was 1358 m / min.
- the first reaction solution was sampled over time.
- the phases were quickly separated.
- the fluorine concentration in the lower aqueous phase was measured with a fluorine ion meter.
- the fluorine-containing hydrochloric acid was sampled over time at the inlet of the first reaction tank 300, and the fluorine concentration in the fluorine-containing hydrochloric acid was measured.
- FIG. 19 shows that the fluorine concentration in the aqueous phase was maintained at 100 ppm or less at the outlet of the first reaction vessel 300.
- the first reaction liquid obtained in the first reaction tank 300 was continuously supplied to the first separation tank 400 having a capacity of 9.7 L.
- the first reaction liquid supplied to the first separation tank 400 was promptly phase-separated.
- the residence time in the first separation tank 400 was set to 27.0-33.6 minutes.
- the TMFS concentration in the upper organic phase was monitored, the TMFS concentration was 40694 to 66551 ppm.
- the HMDS concentration and the TMFS concentration in the lower aqueous phase were monitored, the HMDS concentration was maintained at 400 ppm or less, and the TMFS concentration was maintained at 10 ppm or less.
- an aqueous phase was obtained as a purified aqueous solution.
- the upper organic phase containing overflowed TMFS and HMDS was fed to a subsequent regeneration step. The results are shown in Table 10.
- the second reaction tank 500 used in the regeneration step has a capacity of 5.4 L, and includes a conduit 6 and a pump 61 for taking out the liquid in the second reaction tank and returning it to the second reaction tank.
- a second discharge member 101 is attached to the distal end of the conduit 6.
- the second ejection member 101 includes a second nozzle 111 and a second diffuser 211 attached to the tip of the second nozzle 111, and the second diffuser 211 is provided at the tip of the second nozzle 111.
- a plurality of openings are provided on the side.
- the inner diameter of the tip of the second nozzle 111 was 1.5 mm.
- the apparatus was set so that the liquid overflowed from the second reaction tank 500 was supplied to the second separation tank 600, and a continuous regeneration process was performed according to the following procedure.
- the organic phase containing TMFS and HMDS recovered in the first separation step and a 5 wt% NaOH aqueous solution were continuously supplied to the second reaction vessel 500.
- the flow rate of the HMDS solution was set to about 84.8 mL / min
- the flow rate of the NaOH aqueous solution was set to 93.13 mL / min
- the residence time was set to 22.93 minutes.
- the liquid taken out from the lower side of the second reaction tank 500 was returned into the second reaction tank 500 through the conduit 6 and the pump 61, whereby the liquid in the reaction tank 500 was mixed.
- the flow rate of the liquid discharged from the tip of the nozzle was set to 1.4 L / min.
- the linear velocity of the discharge flow at the tip of the second nozzle 111 was 792 m / min.
- the second reaction solution was sampled over time at the outlet of the second reaction vessel 500.
- the phases were quickly separated.
- the TMFS concentration in the upper organic phase was measured.
- the organic phase was sampled over time at the inlet of the second reaction vessel 500, and the TMFS concentration in the organic phase was measured.
- Table 11 and FIG. As shown in FIG. 20, at the outlet of the second reaction tank 500, the TMFS concentration in the organic phase was kept undetected (less than 0.1 ppm). From this, it can be seen that TMFS present in the organic phase was regenerated into HMDS in the regeneration step.
- fluorine-containing hydrochloric acid can be continuously treated, and fluorine of 100 ppm or less Concentration could be achieved.
- the method and apparatus for treating a fluorine-containing aqueous solution of the present invention can efficiently treat a large amount of waste liquid generated in a fluorine compound production process at low cost.
Abstract
Description
フッ素含有水溶液が第1の向流式反応塔の上部に供給され、ジシロキサン化合物が、第1の向流式反応塔の下部に供給され、
第1の向流式反応塔の頂部においてジシロキサン化合物およびモノフルオロシラン化合物を含む有機相が得られ、第1の向流式反応塔の底部においてフッ素含有水溶液よりもフッ素濃度が低減した精製水溶液が得られる、第1の向流式反応塔を含む、フッ素含有水溶液を処理するための装置が提供される。
反応工程は、フッ素含有水溶液中のフッ素イオンをジシロキサン化合物と反応させて、モノフルオロシラン化合物を含む第1の反応液を得る工程である。本発明の方法により処理することができるフッ素含有水溶液は特に限定されるものではなく、フッ素イオン(F-)ならびにSiF6 2-、BF4 -、PF6 -およびSO3F-等のフッ素含有イオンの1種以上を含有する種々の水溶液、例えばHF、H2SiF6、HBF4、HPF6およびHSO3Fの1種以上を含有する水溶液を処理することができる。本発明の方法により、フッ素濃度が100~50000ppm程度のフッ素含有水溶液を処理して、水溶液中のフッ素濃度を1~100ppm程度に低下させることができる。なお、本明細書において、「フッ素濃度」は、対象とする液体中のフッ素イオンおよびフッ素の重量濃度を意味し、例えば、フッ素濃度1000ppmは、フッ素含有水溶液1kg中にフッ素イオンおよびフッ素が1g存在する濃度を意味する。
ジシロキサン化合物は水に不溶であるので、フッ素含有水溶液とは互いに混和せず、ジシロキサン化合物を含む有機相(軽液)とフッ素含有水溶液を含む水相(重液)とに相分離する。そのため、フッ素含有水溶液中のフッ素イオンとジシロキサン化合物との反応は、有機相と水相との界面においてのみ進行し得る。更に、ジシロキサン化合物は安定な化合物であるため、式(I)の反応速度は比較的遅く、反応に長時間を要する。
本発明の一の実施形態において、反応工程は、図2に示す第1の反応槽300において行うことができる。反応工程における鉛直方向の混合は、第1の反応槽300から取り出された液体を、第1の反応槽300内の液体中において、第1のノズル1を備える第1の吐出部材100から鉛直方向に吐出することにより行われる。第1の反応槽300からの液体の取り出しは、導管6を介して行うことができる。場合によりポンプ61を用いてもよい。本明細書において、「鉛直方向に吐出する」とは、液体の吐出方向が、水相と有機相とが相分離せず均一な混合状態が達成される程度に、混合される物質の鉛直方向の移動をもたらすものであることを意味する。液体の吐出方向は、鉛直方向の成分以外の成分を含んでいてもよい。液体の吐出方向は、吐出部材の取り付け角度によって決定される。取り付け角度は、鉛直方向(鉛直上方向または鉛直下方向)に対して好ましくは0°~60°、より好ましくは0°~30°に設定される。吐出部材の取り付け角度が上述の範囲内であると、鉛直方向の吐出を効果的にもたらすことができ、鉛直方向の混合を効果的に達成することができる。取り付け角度は、より一層好ましくは鉛直方向に対して0°(即ち鉛直上方向または鉛直下方向)である。吐出部材の取り付け角度が鉛直方向に対して0°であると、鉛直方向の混合をより一層効果的に達成することができる。
反応工程における一の時点において、鉛直方向の混合を停止したと仮定した場合、第1の反応槽300内の液体は、上側の有機相と下側の水相とに相分離すると考えられる。このような仮想的な相分離は、図4に示すように、第1の反応槽300内の液体に含まれる水性成分の全体積(51)の上に、第1の反応槽300内の液体に含まれる有機成分の全体積(41)が位置するというモデルで表すことができる。第1の吐出部材は、このようなモデルを仮定した場合に第1のノズル1の先端13が有機成分41中に位置するように配置されることが好ましい。ジシロキサン化合物は、水よりも比重が小さいので、この仮想上の有機成分41が占める領域に比較的多く存在する傾向にある。従って、第1のノズル1の先端13がこの仮想上の有機成分41中に位置するように第1の吐出部材100が配置されると、ノズル1の先端13から鉛直下方向に吐出される吐出流(図3において符号3で示す)は、その周りに多く存在し得るジシロキサン化合物を側方からの吸い込み流31として吸い込むことができる。その結果、ジシロキサン化合物を多く含み得る吸い込み流31の加わった鉛直方向の噴射流がもたらされ、それによりジシロキサン化合物の鉛直方向の移動が促進される。このようにして、鉛直方向の効果的な混合を達成することができる。
本発明のもう一つの実施形態において、反応工程における鉛直方向の混合は、フッ素含有水溶液およびジシロキサン化合物に超音波を照射することにより行われる。超音波の照射による混合の一例を図6に示す。超音波による混合は、図2における第1の反応槽300による反応工程(図において破線で囲まれた部分)の代わりに、図6に示す第1の管型反応器9による反応工程を実施することによって行うことができる。
本発明の更にもう一つの実施形態において、反応工程における鉛直方向の混合は、向流接触法により行うことも可能である。向流接触法による混合は、第1の向流式反応塔であって、フッ素含有水溶液が第1の向流式反応塔の上部に供給され、ジシロキサン化合物が、第1の向流式反応塔の下部に供給され、第1の向流式反応塔の頂部においてジシロキサン化合物およびモノフルオロシラン化合物を含む有機相が得られ、第1の向流式反応塔の底部においてフッ素含有水溶液よりもフッ素濃度が低減した精製水溶液が得られる、第1の向流式反応塔において行うことができる。向流接触法による混合の一例を図7に示す。図7に示す例において、向流接触法による混合は、充填物が充填された第1の向流式反応塔10において行われる。本実施形態において使用可能な充填物は特に限定されるものではなく、ラシヒリング、デミスタ-等の充填物を適宜用いることができる。フッ素含有水溶液8は、導管6およびポンプ61を介して、第1の向流式反応塔10の上部に供給される。一方、ジシロキサン化合物7は、導管6およびポンプ61を介して、第1の向流式反応塔10の下部に供給される。フッ素含有水溶液8およびジシロキサン化合物7の供給量および滞留時間は、使用する装置等に応じて適宜設定することができる。ジシロキサン化合物は水より比重が小さいので、反応塔10の上部において供給されるフッ素含有水溶液は、重力の作用により反応塔10中を下方向に移動し、一方、反応塔10の下部において供給されるジシロキサン化合物は反応塔10中を上方向に移動する。このようなジシロキサン化合物およびフッ素含有水溶液両方の鉛直方向の移動により、フッ素含有水溶液中のフッ素イオンとジシロキサン化合物との接触機会が増大し、反応を効果的に進行させることができる。このようにして、ジシロキサン化合物とフッ素含有水溶液との向流接触を行った結果、反応塔の頂部においてジシロキサン化合物およびモノフルオロシラン化合物を含む有機相を得ることができ、一方、反応塔の底部において、フッ素含有水溶液よりもフッ素濃度が低減した精製水溶液を得ることができる。
本発明の方法は、場合により第1の分離工程を含む。第1の分離工程は、反応工程において得られる第1の反応液を、有機相と水相とに分離する工程である。反応工程において生成するモノフルオロシラン化合物および未反応のジシロキサン化合物は水に不溶であるので、有機相はジシロキサン化合物およびモノフルオロシラン化合物を含み、水相は、ジシロキサン化合物およびモノフルオロシラン化合物を実質的に含まない。第1の分離工程において、水相を、フッ素含有水溶液よりもフッ素濃度が低減した精製水溶液として得ることができる。なお、反応工程における混合を向流接触法によって行う場合、第1の分離工程は不要である。
本発明の方法は、場合により再生工程および第2の分離工程を更に含む。再生工程は、フッ素含有水溶液中のフッ素イオンとジシロキサン化合物との反応により生成するモノフルオロシラン化合物を、塩基と反応させることによりジシロキサン化合物へと再生する工程である。
第2の分離工程は、再生工程で得られる第2の反応液を、ジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相と、フッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相とに相分離させるための工程である。なお、再生工程における混合を向流接触法によって行う場合、第2の分離工程は不要である。
下記の試験1~5において、本願の反応工程に要する時間を、種々の混合方法を用いて調べた。試験1~5はいずれも室温で行った。
試験1は、容量1Lの反応槽を用いて行った。反応槽は、反応槽内の液体を取り出して反応槽内に戻すための導管およびポンプを備える。
試験2は、容量5Lの反応槽を用いて行った。反応槽は、反応槽内の液体を取り出して反応槽内に戻すための導管およびポンプを備える。導管の先端の内径は4.37mmであった。
塩化水素濃度13重量%、フッ素濃度2518ppmのフッ素含有塩酸3.75L(4.01kg)およびヘキサメチルジシロキサン(HMDS)0.51L(0.39kg)を使用し、導管から吐出される液体の流量を1.43L/minに設定した以外は試験1と同様の手順で試験2を行った。混合の間、反応槽内の液体は、相分離することなく均一に混合された状態になった。
試験3は、容量13Lの反応槽を用いて行った。反応槽は、反応槽内の液体を取り出して反応槽内に戻すための導管およびポンプを備える。導管の先端に吐出部材を取り付けた。吐出部材は、ノズルと、ノズルの先端に取り付けられたディフューザーとを有し、ディフューザーは、ノズルの先端の側方において複数の開口部を有する。ノズルの先端の内径は1.5mmであった。
試験4は、試験3で使用した反応槽と同様のものを用いて行った。反応槽は、反応槽内の液体を取り出して反応槽内に戻すための導管およびポンプを備える。導管の先端に吐出部材を取り付けた。吐出部材は、ノズルと、ノズルの先端に取り付けられたディフューザーとを有し、ディフューザーは、ノズルの先端の側方において複数の開口部を有する。ノズルの先端の内径は1.5mmであった。
塩化水素濃度13重量%、フッ素濃度1829ppmのフッ素含有塩酸9.7L(10.3kg)およびヘキサメチルジシロキサン(HMDS)1.51L(1.15kg)を使用し、ノズルの先端から吐出される液体の流量を1.4L/minに設定した以外は試験3と同様の手順で試験4を行った。反応槽内の液体は、相分離することなく均一に混合された状態になった。
塩化水素濃度14重量%、フッ素濃度2158ppmのフッ素含有塩酸0.014L(0.015kg)およびヘキサメチルジシロキサン(HMDS)0.020L(0.015kg)を容量が250mLの反応槽に入れたところ、二相に分離した。反応槽内の液体をスターラーチップで攪拌して混合を行った。スターラーチップの回転数は1000rpmに設定した。攪拌の間、反応槽内の液体は相分離したままであった。攪拌の間、下側の水相を経時的にサンプリングし、水相におけるフッ素濃度をフッ素イオンメーターにより測定した。
下記の試験6~8において、図6に示す管型反応器9および振動子92を備える超音波発生装置91を用いて反応工程を行った。管型反応器9の内径は1/8インチ(0.32cm)、全長は20mとした。この管型反応器9を超音波発生装置91内に設け、媒体として純水を満たした。管型反応器9内の温度は35℃に設定した。超音波発生装置91の出力を400W、振動子92の周波数を38kHzに設定した。
塩化水素濃度14重量%、フッ素濃度2136ppmのフッ素含有塩酸100.91gと、HMDS16.98gとを、ポンプ61を用いて管型反応器9に連続的に供給した。滞留時間(即ち超音波の照射時間)は13.6分に設定した。管型反応器9から取り出した液体を静置したところ、速やかに二相に分離した。下側の水相におけるフッ素濃度をフッ素イオンメーターにより測定した。
フッ素含有塩酸の使用量を292.38g、HMDSの使用量を18.00g、滞留時間を5.45分とした以外は試験6と同様の手順で試験7を行った。
フッ素含有塩酸の使用量を384.15g、HMDSの使用量を97.85g、滞留時間を1.63分とした以外は試験6と同様の手順で試験8を行った。
反応工程における反応に要する時間の温度依存性を調べるために、下記の試験9および10を行った。
混合時の温度を50℃に設定した以外は試験5と同様の手順で試験9を行った。混合の間、反応槽内の液体は相分離したままであった。
混合時の温度を80℃に設定した以外は試験5と同様の手順で試験10を行った。混合の間、反応槽内の液体は相分離したままであった。
反応工程における反応に要する時間の塩化水素濃度依存性を調べるために、下記の試験11~14を行った。
塩化水素濃度0重量%、フッ素濃度1976ppmのフッ素含有塩酸を用いた以外は試験5と同様の手順で試験11を行った。
塩化水素濃度20.3重量%、フッ素濃度2100ppmのフッ素含有塩酸を用いた以外は試験5と同様の手順で試験12を行った。
塩化水素濃度24.6重量%、フッ素濃度2000ppmのフッ素含有塩酸を用いた以外は試験5と同様の手順で試験13を行った。
塩化水素濃度28.7重量%、フッ素濃度1800ppmのフッ素含有塩酸を用いた以外は試験5と同様の手順で試験14を行った。
(フッ素除去率)%={(混合開始前にフッ素含有塩酸中に存在するフッ素イオンおよびフッ素の重量)-(混合後に水相中に残存するフッ素イオンおよびフッ素の重量)}/(混合開始前にフッ素含有塩酸中に存在するフッ素イオンおよびフッ素の重量)×100
図11に示すように、フッ素含有塩酸中の塩化水素濃度が高いほど、フッ素除去率が高くなった。このことより、フッ素含有塩酸中の塩化水素濃度が高いほど、反応工程に要する時間が短縮可能であることがわかる。
(試験15)
試験3と同様の手順で反応工程を実施した。混合開始から10分後に混合を停止した。混合停止時における水相中のフッ素濃度は14ppmであった。反応槽内の液体は、混合停止後速やかに二相に分離した。反応槽内の液体を静置し、上側の有機相および下側の水相を経時的にサンプリングした。サンプリングした水相中のHMDS濃度およびテトラメチルフルオロシラン(TMFS)濃度をガスクロマトグラフィーにより測定し、ならびにサンプリングした有機相中の塩化水素濃度をイオンクロマトグラフィーにより測定した。混合を停止してから120分後、有機相および水相を別々に回収した。結果を表3ならびに図12および図13に示す。図12および図13において、「静置時間」は混合を停止した時点からの時間を意味する。水相中のTMFS濃度は混合を停止した時点において10ppm以下であり、反応工程により水相中のフッ素化合物が除去されたことがわかる。有機相中の塩化水素濃度は30分以内に20ppm以下まで低下した。また、水相中のHMDS濃度は30分以内に300ppm以下まで低下した。以上の結果より、混合停止から30分程度で第1の分離工程を完了させることができることがわかった。
(試験16)
試験15において回収した有機相中のTMFS濃度をガスクロマトグラフィーで測定したところ、6.2重量%であった。TMFSおよびHMDSを含むこの有機相1.764L(1.348kg)と、塩基性水溶液としての5重量%水酸化ナトリウム(NaOH)水溶液2.794L(2.934kg)とを、容量5Lの反応槽に入れた。反応槽は、反応槽内の液体を取り出して反応槽内に戻すための導管およびポンプを備えるものであり、導管の先端には、ノズルおよびディフューザーを備える吐出部材が取り付けられている。ノズルの先端の内径は1.5mmであった。有機相中に存在するトリメチルフルオロシランに対する、NaOH水溶液中に存在するNaOHのモル比はNaOH/TMFS=4.0であった。
第1の分離工程において得られる有機相に含まれるTMFSに対する、再生工程において用いられる塩基性水溶液に含まれる塩基のモル比と、HMDS再生率との関係を調べるために、下記の試験17~22を行った。試験17~22はいずれも室温において行った。
TMFS濃度が35328ppmのHMDS溶液29.51gと、5重量%のNaOH水溶液0.93gとをスクリュー管に入れて密封した。HMDS溶液に含まれるTMFSに対するNaOHのモル比は0.1であった。このスクリュー管を、有機相-水相の界面に対して垂直な方向、即ち鉛直方向に200~250rpm程度で15分間混合を行った。混合終了後、スクリュー管を静置したところ、内部の液体は速やかに相分離した。上側の有機相および下側の水相のサンプリングをそれぞれ行った。ガスクロマトグラフィーにより有機相中のTMFS濃度を測定した。pH計により水相のpHを測定した。
HMDS溶液の量を30.01g、NaOH水溶液の量を4.61gとした以外は試験17と同様の手順で試験18を行った。HMDS溶液に含まれるTMFSに対するNaOHのモル比は0.5であった。試験終了後、水相のpHおよび有機相中のTMFS濃度を測定した。
HMDS溶液の量を29.98g、NaOH水溶液の量を9.21gとした以外は試験17と同様の手順で試験19を行った。HMDS溶液に含まれるTMFSに対するNaOHのモル比は1.0であった。試験終了後、水相のpHおよび有機相中のTMFS濃度を測定した。
HMDS溶液の量を30.00g、NaOH水溶液の量を11.98gとした以外は試験17と同様の手順で試験20を行った。HMDS溶液に含まれるTMFSに対するNaOHのモル比は1.3であった。試験終了後、水相のpHおよび有機相中のTMFS濃度を測定した。
HMDS溶液の量を19.96g、NaOH水溶液の量を9.34gとした以外は試験17と同様の手順で試験21を行った。HMDS溶液に含まれるTMFSに対するNaOHのモル比は1.5であった。試験終了後、水相のpHおよび有機相中のTMFS濃度を測定した。
HMDS溶液の量を20.01g、NaOH水溶液の量を11.21gとした以外は試験17と同様の手順で試験22を行った。HMDS溶液に含まれるTMFSに対するNaOHのモル比は1.8であった。試験終了後、水相のpHおよび有機相中のTMFS濃度を測定した。
(HMDS再生率)%={(混合開始前にHMDS溶液中に存在するTMFSの重量)-(混合後に有機相中に残存したTMFSの重量)}/(混合開始前にHMDS溶液中に存在するTMFSの重量)×100
表5および図15より、TMFSに対するNaOHのモル比が1.3以上である場合、混合時間15分において99%以上のHMDS再生率を達成できたことがわかる。
下記の試験23~27において、スタティックミキサーを用いて再生工程を行った。試験23~27はいずれも、室温において内径9.52mm、全長180mmのスタティックミキサーを用いて行った。
試験23において、TMFSおよびHMDSを含む有機相と、5重量%NaOH水溶液とをスタティックミキサーに連続的に供給した。有機相の供給流量は1.179L/min、NaOH水溶液の供給流量は0.166L/min、スタティックミキサーの入口における液体(有機相およびNaOH水溶液の合計)の流速は0.315m/sであった。スタティックミキサーの出口において液体を経時的にサンプリングした。サンプリングした液体を静置すると、速やかに相分離した。上側の有機相中のTMFS濃度をガスクロマトグラフィーにより測定した。
有機相の供給流量を0.236L/min、NaOH水溶液の供給流量を0.196L/min、スタティックミキサーの入口における液体(有機相およびNaOH水溶液の合計)の流速を0.101m/sとした以外は試験23と同様の手順で試験24を行った。
有機相の供給流量を0.236L/min、NaOH水溶液の供給流量を0.0646L/min、スタティックミキサーの入口における液体(有機相およびNaOH水溶液の合計)の流速を0.07m/sとした以外は試験23と同様の手順で試験25を行った。
有機相の供給流量を0.236L/min、NaOH水溶液の供給流量を0.238L/min、スタティックミキサーの入口における液体(有機相およびNaOH水溶液の合計)の流速を0.10m/sとした以外は試験23と同様の手順で試験26を行った。
有機相の供給流量を1.179L/min、NaOH水溶液の供給流量を0.238L/min、スタティックミキサーの入口における液体(有機相およびNaOH水溶液の合計)の流速を0.33m/sとした以外は試験23と同様の手順で試験27を行った。
(試験28)
試験16と同様の手順で再生工程を実施した。混合開始から10分後に混合を停止した。混合停止時における有機相中のTMFS濃度は未検出(0.1ppm未満)であった。反応槽内の液体は、混合停止後速やかに二相に分離した。混合を停止した後、下側の水相を経時的にサンプリングした。サンプリングした水相中のHMDS濃度をガスクロマトグラフィーにより測定した。混合を停止してから120分後、有機相および水相を別々に回収した。結果を表7および図17に示す。図17において、「静置時間」は混合を停止した時点からの時間を意味する。水相中のHMDS濃度は25分以内に約300ppmまで低下した。この結果より、混合停止から25分程度で第2の分離工程を完了させることができることがわかった。
(試験29)
試験28において回収した有機相、即ち再生されたHMDSを1.5L(1.13kg)と、塩化水素濃度12.8重量%、フッ素濃度1829ppmのフッ素含有水溶液9.3L(9.95kg)とを用いた以外は試験3と同様の手順で試験29を行った。
(試験30)
図2に示す装置を用いて、反応工程、第1の分離工程、再生工程、第2の分離工程を行った。各工程は連続式で行った。
(反応工程)
反応工程において使用した第1の反応槽300は、容量5.3Lであり、反応槽内の液体を取り出して反応槽内に戻すための導管6およびポンプ61を備える。導管6の先端には第1の吐出部材100が取り付けられている。第1の吐出部材100は、第1のノズル1と、ノズル1の先端に取り付けられた第1のディフューザー2とを備え、第1のディフューザー2は、第1のノズル1の先端の側方において複数の開口部を有する。第1のノズル1の先端の内径は1.5mmであった。
第1の反応槽300に、塩化水素濃度15.6重量%、フッ素濃度約1770~1930ppmのフッ素含有塩酸と、HMDSとを連続的に供給し、オーバーフローした液体を後続の第1の分離槽400に供給した。塩酸の流量を約207~264mL/min、HMDSの流量を約30~34mL/min、滞留時間を約13~17分に設定した。第1の反応槽300の下方から取り出した液体を、導管6およびポンプ61を介して第1の反応槽300内に戻すことにより、第1の反応槽300内の液体を混合した。第1のノズル1の先端から吐出される液体の流量は2.4L/minに設定した。第1のノズル1の先端における吐出流の線速度は1358m/minであった。第1の反応槽300内の温度および圧力をモニタリングしたところ、温度上昇および圧力上昇は観察されなかった。第1の反応槽300の出口において、第1の反応液を経時的にサンプリングした。サンプリングした液体を静置すると、速やかに相分離した。下側の水相中のフッ素濃度をフッ素イオンメーターにより測定した。また第1の反応槽300の入口においてフッ素含有塩酸を経時的にサンプリングし、フッ素含有塩酸中のフッ素濃度を測定した。結果を表9および図19に示す。なお、表9および図19に記載のデータは、連続式で反応工程を開始した時点を起点(ゼロ分)としている。図19より、第1の反応槽300の出口において、水相中のフッ素濃度が100ppm以下に保持されたことがわかる。
第1の反応槽300において得られた第1の反応液を、容量9.7Lの第1の分離槽400に連続的に供給した。第1の分離槽400に供給された第1の反応液は速やかに相分離した。第1の分離槽400における滞留時間は27.0~33.6分に設定した。上側の有機相中のTMFS濃度のモニタリングを行ったところ、TMFS濃度は40694~66551ppmであった。下側の水相中のHMDS濃度およびTMFS濃度のモニタリングを行った所、HMDS濃度は400ppm以下に保持され、TMFS濃度は10ppm以下に保持された。第1の分離槽の下方部分において、水相を精製水溶液として得た。オーバーフローしたTMFSおよびHMDSを含む上側の有機相を後続の再生工程に供給した。結果を表10に示す。
再生工程において使用した第2の反応槽500は、容量5.4Lであり、第2の反応槽内の液体を取り出して第2の反応槽内に戻すための導管6およびポンプ61を備える。導管6の先端には第2の吐出部材101が取り付けられている。第2の吐出部材101は、第2のノズル111と、第2のノズル111の先端に取り付けられた第2のディフューザー211とを備え、第2のディフューザー211は、第2のノズル111の先端の側方において複数の開口部を有する。第2のノズル111の先端の内径は1.5mmであった。
第1の分離工程において回収されたTMFSおよびHMDSを含む有機相と、5重量%のNaOH水溶液とを第2の反応槽500に連続的に供給した。HMDS溶液の流量を約84.8mL/min、NaOH水溶液の流量を93.13mL/min、滞留時間を22.93分に設定した。第2の反応槽500の下方から取り出した液体を、導管6およびポンプ61を介して第2の反応槽500内に戻すことにより、反応槽500内の液体を混合した。ノズルの先端から吐出される液体の流量は1.4L/minに設定した。第2のノズル111の先端における吐出流の線速度は792m/minであった。第2の反応槽500内の温度および圧力をモニタリングしたところ、温度上昇および圧力上昇は観察されなかった。第2の反応槽500の出口において、第2の反応液を経時的にサンプリングした。サンプリングした液体を静置すると、速やかに相分離した。上側の有機相中のTMFS濃度を測定した。また、第2の反応槽500の入口において有機相を経時的にサンプリングし、有機相中のTMFS濃度を測定した。結果を表11および図20に示す。図20に示すように、第2の反応槽500の出口において、有機相中のTMFS濃度は未検出(0.1ppm未満)に保持された。このことより、再生工程において、有機相中に存在するTMFSがHMDSへと再生されたことがわかる。
第2の反応槽500において得られる第2の反応液を、容量5.1Lの第2の分離槽600に連続的に供給した。第2の分離槽600に供給された第2の反応液は速やかに相分離した。第2の分離溶液における滞留時間は23.88分に設定した。結果を表12および図21に示す。上側の有機相中のTMFS濃度のモニタリングを行ったところ、TMFS濃度は未検出(0.1ppm未満)に保持された。下側の水相中のHMDS濃度およびTMFS濃度のモニタリングを行った所、HMDS濃度は500ppm以下に保持され、TMFS濃度は未検出(0.1ppm未満)に保持された。第2の分離槽の下方部分において、下側の水相をフッ化物塩含有液として得た。オーバーフローした有機相を回収し、再生されたHMDSとして反応工程にフィードバックした。
101 第2の吐出部材
1 第1のノズル
111 第2のノズル
13 第1のノズルの先端
2 第1のディフューザー
211 第2のディフューザー
21 第1のディフューザーの開口部
22 第1のディフューザーの開口部側の端部
23 第1のディフューザーの先端
3 第1のノズルの先端からの吐出流
31 側方からの吸い込み流
32 第1のディフューザーの先端からの噴射流
4 有機相
41 有機成分
5 水相
51 水性成分
6 導管
61 ポンプ
7 ジシロキサン化合物
8 フッ素含有水溶液
9 第1の管型反応器
91 超音波発生装置
92 振動子
10 第1の向流式反応塔
300 第1の反応槽
400 第1の分離槽
500 第2の反応槽
600 第2の分離槽
Claims (41)
- フッ素含有水溶液と、一般式RaRbRcSiOSiRdReRf(式中、Ra、Rb、Rc、Rd、ReおよびRfはそれぞれ独立して炭素数1~20のアルキル基およびフェニル基ならびに水素からなる群から選択される)で表されるジシロキサン化合物とを鉛直方向に混合することによりフッ素含有水溶液中のフッ素イオンをジシロキサン化合物と反応させて、一般式RaRbRcSiFおよびRdReRfSiFで表されるモノフルオロシラン化合物を含む第1の反応液を得る反応工程を含む、フッ素含有水溶液の処理方法。
- 反応工程が第1の反応槽において行われ、反応工程における鉛直方向の混合が、第1の反応槽から取り出された液体を、第1の反応槽内の液体中において、第1のノズルを備える第1の吐出部材から鉛直方向に吐出することにより行われる、請求項1に記載の方法。
- 反応工程における鉛直方向の混合が、第1の反応槽の下方部分から取り出された液体を、第1の反応槽内の液体中の上方部分において、第1のノズルを備える第1の吐出部材から鉛直下方向に吐出することにより行われる、請求項1または2に記載の方法。
- 第1の反応槽内の液体に含まれる水性成分の全体積の上に、第1の反応槽内の液体に含まれる有機成分の全体積が位置すると仮定したとき、第1の吐出部材は、第1のノズルの先端が有機成分中に位置するように配置される、請求項3に記載の方法。
- 反応工程における鉛直方向の混合が、水性成分の下方部分から取り出された液体を、第1の吐出部材から鉛直下方向に吐出することにより行われる、請求項4に記載の方法。
- 反応工程における鉛直方向の混合が、第1の反応槽の上方部分から取り出された液体を、第1の反応槽内の液体中の下方部分において、第1のノズルを備える第1の吐出部材から鉛直上方向に吐出することにより行われる、請求項1または2に記載の方法。
- 第1の反応槽内の液体に含まれる水性成分の全体積の上に、第1の反応槽内の液体に含まれる有機成分の全体積が位置すると仮定したとき、第1の吐出部材は、第1のノズルの先端が水性成分中に位置するように配置される、請求項6に記載の方法。
- 反応工程における鉛直方向の混合が、有機成分の上方部分から取り出された液体を、第1の吐出部材から鉛直上方向に吐出することにより行われる、請求項7に記載の方法。
- 第1の吐出部材が、第1のノズルの先端に取り付けられた第1のディフューザーを更に備え、第1のディフューザーは、第1のノズルの先端の側方において1以上の開口部を有する、請求項2~8のいずれか1項に記載の方法。
- 第1のノズルの先端における吐出流の線速度が500~2000m/minである、請求項2~9のいずれか1項に記載の方法。
- 反応工程における鉛直方向の混合が、フッ素含有水溶液およびジシロキサン化合物に超音波を照射することにより行われる、請求項1に記載の方法。
- フッ素含有水溶液が酸性水溶液である、請求項1~11のいずれか1項に記載の方法。
- フッ素含有水溶液がフッ素含有塩酸である、請求項12に記載の方法。
- フッ素含有水溶液の酸濃度が10重量%以上である、請求項12または13に記載の方法。
- 反応工程を50℃以上の温度で行う、請求項1~14のいずれか1項に記載の方法。
- ジシロキサン化合物がヘキサメチルジシロキサンである、請求項1~15のいずれか1項に記載の方法。
- 反応工程において得られる第1の反応液を、ジシロキサン化合物およびモノフルオロシラン化合物を含む有機相と、ジシロキサン化合物およびモノフルオロシラン化合物を実質的に含まない水相とに相分離させて、水相を、フッ素含有水溶液よりもフッ素濃度が低減した精製水溶液として得る第1の分離工程を更に含む、請求項1~16のいずれか1項に記載の方法。
- 第1の分離工程において得られる有機相と塩基性水溶液とを混合することにより、有機相に含まれるモノフルオロシラン化合物を塩基性水溶液に含まれる塩基と反応させて、ジシロキサン化合物およびフッ化物塩を含む第2の反応液を得る再生工程
を更に含む、請求項17に記載の方法。 - 再生工程が、第2の反応槽において、第1の分離工程において得られる有機相と塩基性水溶液とを鉛直方向に混合することにより行われ、再生工程における鉛直方向の混合が、第2の反応槽から取り出された液体を、第2の反応槽内の液体中において、第2のノズルを備える第2の吐出部材から鉛直方向に吐出することにより行われる、請求項18に記載の方法。
- 再生工程における鉛直方向の混合が、第2の反応槽の下方部分から取り出された液体を、第2の反応槽内の液体中の上方部分において、第2のノズルを備える第2の吐出部材から鉛直下方向に吐出することにより行われる、請求項18または19に記載の方法。
- 第2の反応槽内の液体に含まれる水性成分の全体積の上に、第2の反応槽内の液体に含まれる有機成分の全体積が位置すると仮定したとき、第2の吐出部材は、第2のノズルの先端が有機成分中に位置するように配置される、請求項20に記載の方法。
- 再生工程における鉛直方向の混合が、水性成分の下方部分から取り出された液体を、第2の吐出部材から鉛直下方向に吐出することにより行われる、請求項21に記載の方法。
- 再生工程における鉛直方向の混合が、第2の反応槽の上方部分から取り出された液体を、第2の反応槽内の液体中の下方部分において、第2のノズルを備える第2の吐出部材から鉛直上方向に吐出することにより行われる、請求項18または19に記載の方法。
- 第2の反応槽内の液体に含まれる水性成分の全体積の上に、第2の反応槽内の液体に含まれる有機成分の全体積が位置すると仮定したとき、第2の吐出部材は、第2のノズルの先端が水性成分中に位置するように配置される、請求項23に記載の方法。
- 再生工程における鉛直方向の混合が、有機成分の上方部分から取り出された液体を、第2の吐出部材から鉛直上方向に吐出することにより行われる、請求項24に記載の方法。
- 第2の吐出部材が、第2のノズルの先端に取り付けられた第2のディフューザーを更に備え、第2のディフューザーは、第2のノズルの先端の側方において1以上の開口部を有する、請求項19~25のいずれか1項に記載の方法。
- 第2のノズルの先端における吐出流の線速度が500~2000m/minである、請求項19~26のいずれか1項に記載の方法。
- 再生工程における鉛直方向の混合が、第1の分離工程において得られる有機相および塩基性水溶液に超音波を照射することにより行われる、請求項18に記載の方法。
- 第1の分離工程において得られる有機相に含まれるモノフルオロシラン化合物に対する、再生工程において用いられる塩基性水溶液に含まれる塩基のモル比が1.3以上である、請求項18~28のいずれか1項に記載の方法。
- 再生工程で得られる第2の反応液を、ジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相と、フッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相とに相分離させる第2の分離工程を更に含み、
第2の分離工程において得られる有機相を、ジシロキサン化合物として反応工程において再利用する、請求項18~29のいずれか1項に記載の方法。 - フッ素含有水溶液とジシロキサン化合物とを混合することによりフッ素含有水溶液中のフッ素イオンをジシロキサン化合物と反応させて、モノフルオロシラン化合物を含む第1の反応液を得るための第1の反応槽であって、第1の反応槽から取り出された液体を第1の反応槽内で吐出するための導管を備え、第1のノズルを備える第1の吐出部材が導管の先端に取り付けられている、第1の反応槽を含む、フッ素含有水溶液を処理するための装置。
- 第1の吐出部材が、第1のノズルの先端に取り付けられた第1のディフューザーを更に備え、第1のディフューザーは、第1のノズルの先端の側方において1以上の開口部を有する、請求項31に記載の装置。
- 第1の反応槽において得られる第1の反応液を、ジシロキサン化合物およびモノフルオロシラン化合物を含む有機相と、ジシロキサン化合物およびモノフルオロシラン化合物を実質的に含まない水相とに相分離させて、水相を、フッ素含有水溶液よりもフッ素濃度が低減した精製水溶液として得るための第1の分離槽、
第1の分離槽において得られる有機相と塩基性水溶液とを混合することにより、有機相に含まれるモノフルオロシラン化合物を塩基性水溶液に含まれる塩基と反応させて、ジシロキサン化合物およびフッ化物塩を含む第2の反応液を得るための第2の反応槽であって、第2の反応槽から取り出された液体を第2の反応槽内で吐出するための導管を備え、第2のノズルを備える第2の吐出部材が導管の先端に取り付けられている、第2の反応槽、ならびに
第2の反応槽において得られる第2の反応液を、ジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相と、フッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相とに相分離させるための第2の分離槽
を更に含み、
第2の分離槽において得られる有機相をジシロキサン化合物として第1の反応槽において再利用することができる、請求項31または32に記載の装置。 - 第2の吐出部材が、第2のノズルの先端に取り付けられた第2のディフューザーを更に備え、第2のディフューザーは、第2のノズルの先端の側方において1以上の開口部を有する、請求項33に記載の装置。
- フッ素含有水溶液とジシロキサン化合物とを混合することによりフッ素含有水溶液中のフッ素イオンをジシロキサン化合物と反応させて、モノフルオロシラン化合物を含む第1の反応液を得るための第1の管型反応器であって、第1の管型反応器内の流れの方向に沿って第1の管型反応器の下方に配置される振動子により超音波が照射される、第1の管型反応器を含む、フッ素含有水溶液を処理するための装置。
- 第1の管型反応器において得られる第1の反応液を、ジシロキサン化合物およびモノフルオロシラン化合物を含む有機相と、ジシロキサン化合物およびモノフルオロシラン化合物を実質的に含まない水相とに相分離させて、水相を、フッ素含有水溶液よりもフッ素濃度が低減した精製水溶液として得るための第1の分離槽、
第1の分離槽において得られる有機相と塩基性水溶液とを混合することにより、有機相に含まれるモノフルオロシラン化合物を塩基性水溶液に含まれる塩基と反応させて、ジシロキサン化合物およびフッ化物塩を含む第2の反応液を得るための第2の管型反応器であって、第2の管型反応器内の流れの方向に沿って第2の管型反応器の下方に配置される振動子により超音波が照射される、第2の管型反応器、ならびに
第2の管型反応器において得られる第2の反応液を、ジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相と、フッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相とに相分離させるための第2の分離槽
を更に含み、
第2の分離槽において得られる有機相をジシロキサン化合物として第1の管型反応器において再利用することができる、請求項35に記載の装置。 - 第1の向流式反応塔であって、
フッ素含有水溶液が第1の向流式反応塔の上部に供給され、ジシロキサン化合物が、第1の向流式反応塔の下部に供給され、
第1の向流式反応塔の頂部においてジシロキサン化合物およびモノフルオロシラン化合物を含む有機相が得られ、第1の向流式反応塔の底部においてフッ素含有水溶液よりもフッ素濃度が低減した精製水溶液が得られる、第1の向流式反応塔を含む、フッ素含有水溶液を処理するための装置。 - 第2の向流式反応塔であって、
第1の向流式反応塔において得られる有機相が第2の向流式反応塔の下部に供給され、塩基性水溶液が、第2の向流式反応塔の上部に供給され、
第2の向流式反応塔の頂部においてジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相が得られ、第2の向流式反応塔の底部においてフッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相が得られる、第2の向流式反応塔を更に含み、
第2の向流式反応塔において得られる有機相をジシロキサン化合物として第1の向流式反応塔において再利用することができる、請求項37に記載の装置。 - 第1の反応槽において得られる第1の反応液を、ジシロキサン化合物およびモノフルオロシラン化合物を含む有機相と、ジシロキサン化合物およびモノフルオロシラン化合物を実質的に含まない水相とに相分離させて、水相を、フッ素含有水溶液よりもフッ素濃度が低減した精製水溶液として得るための第1の分離槽、
第1の分離槽において得られる有機相と塩基性水溶液とを混合することにより、有機相に含まれるモノフルオロシラン化合物を塩基性水溶液に含まれる塩基と反応させて、ジシロキサン化合物およびフッ化物塩を含む第2の反応液を得るための混合器、ならびに
前記混合器において得られる第2の反応液を、ジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相と、フッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相とに相分離させるための第2の分離槽
を更に含み、
第2の分離槽において得られる有機相をジシロキサン化合物として第1の反応槽において再利用することができる、請求項31または32に記載の装置。 - 第1の管型反応器において得られる第1の反応液を、ジシロキサン化合物およびモノフルオロシラン化合物を含む有機相と、ジシロキサン化合物およびモノフルオロシラン化合物を実質的に含まない水相とに相分離させて、水相を、フッ素含有水溶液よりもフッ素濃度が低減した精製水溶液として得るための第1の分離槽、
第1の分離槽において得られる有機相と塩基性水溶液とを混合することにより、有機相に含まれるモノフルオロシラン化合物を塩基性水溶液に含まれる塩基と反応させて、ジシロキサン化合物およびフッ化物塩を含む第2の反応液を得るための混合器、ならびに
前記混合器において得られる第2の反応液を、ジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相と、フッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相とに相分離させるための第2の分離槽
を更に含み、
第2の分離槽において得られる有機相をジシロキサン化合物として第1の管型反応器において再利用することができる、請求項35に記載の装置。 - 第1の向流式反応塔において得られる有機相と塩基性水溶液とを混合することにより、有機相に含まれるモノフルオロシラン化合物を塩基性水溶液に含まれる塩基と反応させて、ジシロキサン化合物およびフッ化物塩を含む反応液を得るための混合器、ならびに
前記混合器において得られる反応液を、ジシロキサン化合物を含み且つフッ化物塩を実質的に含まない有機相と、フッ化物塩を含み且つジシロキサン化合物を実質的に含まない水相とに相分離させるための分離槽
を更に含み、
前記分離槽において得られる有機相をジシロキサン化合物として第1の向流式反応塔において再利用することができる、請求項37に記載の装置。
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US11919788B2 (en) | 2021-07-19 | 2024-03-05 | 3M Innovative Properties Company | Methods of removing inorganic fluoride from compositions containing fluorinated organic compounds |
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CN106927424A (zh) * | 2017-03-03 | 2017-07-07 | 巨化集团技术中心 | 一种酸性水溶液的除氟方法 |
JP6392476B1 (ja) * | 2018-03-19 | 2018-09-19 | 大輝 中矢 | 生体組織解析装置および生体組織解析プログラム |
CN115400642B (zh) * | 2022-11-01 | 2023-06-30 | 联仕(昆山)化学材料有限公司 | 一种电子级负胶显影液配置搅拌设备 |
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JPS58223604A (ja) * | 1982-06-17 | 1983-12-26 | Daikin Ind Ltd | 塩酸の精製法 |
JPH0144392B2 (ja) * | 1981-10-08 | 1989-09-27 | Nippon Denki Kankyo Enjiniaringu Kk | |
JPH0527564B2 (ja) * | 1988-05-31 | 1993-04-21 | Daikin Ind Ltd |
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US4828712A (en) * | 1987-12-28 | 1989-05-09 | Maxwell Laboratories, Inc. | Extraction of pollutants by inorganic chelation |
JP2798317B2 (ja) * | 1992-02-18 | 1998-09-17 | 信越化学工業株式会社 | モノクロロシラン類の製造方法 |
DE19644561C2 (de) * | 1996-10-26 | 2003-10-16 | Degussa | Verfahren zur Herstellung von Fluoralkyl-Gruppen tragenden Silicium-organischen Verbindungen |
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JPH0144392B2 (ja) * | 1981-10-08 | 1989-09-27 | Nippon Denki Kankyo Enjiniaringu Kk | |
JPS58223604A (ja) * | 1982-06-17 | 1983-12-26 | Daikin Ind Ltd | 塩酸の精製法 |
JPH0527564B2 (ja) * | 1988-05-31 | 1993-04-21 | Daikin Ind Ltd |
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US11919788B2 (en) | 2021-07-19 | 2024-03-05 | 3M Innovative Properties Company | Methods of removing inorganic fluoride from compositions containing fluorinated organic compounds |
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US10562800B2 (en) | 2020-02-18 |
US20170113953A1 (en) | 2017-04-27 |
JP5874852B2 (ja) | 2016-03-02 |
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