Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/08—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles
  • B01J8/10—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles moved by stirrers or by rotary drums or rotary receptacles or endless belts
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C67/00—Preparation of carboxylic acid esters
  • C07C67/30—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group
  • C07C67/333—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by isomerisation; by change of size of the carbon skeleton
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/0015—Feeding of the particles in the reactor; Evacuation of the particles out of the reactor
  • B01J8/003—Feeding of the particles in the reactor; Evacuation of the particles out of the reactor in a downward flow
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/0015—Feeding of the particles in the reactor; Evacuation of the particles out of the reactor
  • B01J8/0035—Periodical feeding or evacuation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/08—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles
  • B01J8/087—Heating or cooling the reactor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C67/00—Preparation of carboxylic acid esters
  • C07C67/48—Separation; Purification; Stabilisation; Use of additives
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00389—Controlling the temperature using electric heating or cooling elements
  • B01J2208/00407—Controlling the temperature using electric heating or cooling elements outside the reactor bed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00389—Controlling the temperature using electric heating or cooling elements
  • B01J2208/00415—Controlling the temperature using electric heating or cooling elements electric resistance heaters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00513—Controlling the temperature using inert heat absorbing solids in the bed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00002—Chemical plants
  • B01J2219/00004—Scale aspects
  • B01J2219/00006—Large-scale industrial plants
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/18—Details relating to the spatial orientation of the reactor
  • B01J2219/182—Details relating to the spatial orientation of the reactor horizontal
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/19—Details relating to the geometry of the reactor
  • B01J2219/194—Details relating to the geometry of the reactor round
  • B01J2219/1941—Details relating to the geometry of the reactor round circular or disk-shaped
  • B01J2219/1943—Details relating to the geometry of the reactor round circular or disk-shaped cylindrical

Definitions

• the invention relates to a method and an arrangement for the recovery of monomeric esters of substituted or unsubstituted acrylic acid, of styrene and / or of monomeric styrene derivatives from polymer material having corresponding structural units.
• Acrylate polymers which mainly include acrylic glasses made from polymethyl methacrylate (PMMA), are used, among other things, to manufacture durable consumer goods. Molding processes are often used for this purpose, in the course of which waste polymer is obtained. For this reason, but also for the recycling of used polymeric waste materials, it makes sense to process it. The same applies to polystyrene and to styrene-containing copolymers and to their processing. Acrylate polymers, especially PMMA, polystyrene and styrene-containing copolymers can advantageously be completely broken down into corresponding monomers again at certain temperatures and pressures.
• PMMA polymethyl methacrylate
• a movement device is provided for moving a material to be moved that has the spherical particles and the polymer material in the reactor.
• the surprising effect of the spherical particles to the depolymerization is probably due to the fact that the balls (z. B. Heating and / or moving means) particularly easily against each other, against 0 surfaces of the reactor and any disposed therein means against differently shaped particles as well as against the polymeric material are displaceable and therefore mix particularly well with one another and with parts of the polymer material. Therefore, an effective heat transfer from the heater to the polymer material and a largely homogeneous temperature distribution can be achieved at least in some areas of the reactor space.
• the diameter of the balls is in the range from 0.075 mm to 0.25 mm, preferably in the range from 0.1 to 0.2 mm.
• the individual has in this size range Ball on the one hand still has a considerable heat capacity for depolymerization and on the other hand - like a particle of a liquid - it is particularly easy to move.
• the movement device can have different configurations. In particular, all variants familiar to the person skilled in the art come into consideration, such as, for. B. moving or rotating walls or moving other parts of the reactor.
• the movement device can also have, for example, a part or more parts which carry out a mechanical oscillation and / or a continuously continued linear (also curved) movement and thereby generate and / or maintain a movement of the material to be moved in the reactor. Movement devices with one or more rotating shafts, which are in particular provided with blade-like curved and / or other mixing tools, are preferred.
• the wave (s) can be z. B. extend in the horizontal or vertical direction. Favorable for a good mixing result is e.g. B.
• a mixer with a shaft extending in the vertical direction in a reactor vessel to which at least one mixing tool protruding in the radial direction of the shaft is attached.
• This embodiment allows a continuous movement of at least part of the goods to be moved, a constant mixing movement taking place within the goods to be moved due to the spherical particles.
• the spherical particles preferably remain in the reactor during the depolymerization and are not - as described in DE 198 43 112 A1 - fed to one end of the reactor and discharged at an opposite end. Remaining in the reactor considerably simplifies the process. In this case, too, the relatively complex and loss-prone heating of the heat carrier outside the reactor described in DE 198 43 112 A1 can be avoided (see the following paragraph).
• the invention is not limited to the fact that the spherical particles remain in the reactor. With other embodiments of the invention, thorough mixing can be achieved in a simple manner compared to conventional heat transfer media or the same mixing can be achieved with simpler means. In particular, lower drive energies and a correspondingly less powerful movement device and a lower heating output are sufficient. Local overheating with the negative effects mentioned above is avoided.
• an inwardly facing surface of an outer wall of the reactor and / or at least part of a movement device arranged in the reactor is heated.
• at least a part of the reactor or within the reactor is connected in a heat-conducting manner to a heater, the part repeatedly coming into contact with individual particles during the movement process of the spherical particles. In this way, good heat transfer to the polymer material is achieved with the aid of the particles.
• the average temperature of the particles of the heat carrier in the reactor is in particular in the range from 250 to 600 degrees Celsius, in the case of recovery of MMA preferably below 425 ° C., the autoignition temperature of MMA.
• Fig. 1 a plant for the recovery of monomeric substances
• FIG. 5 shows a lock device which is connected upstream of the reactor shown in FIG. 1 and serves to introduce polymer material into the reactor.
• the system described below is an exemplary embodiment. Individual or multiple system components can be replaced by other components.
• the feed of the polymer material into the reactor described below, the reactor itself and / or the processing of the monomer gas derived from the reactor can be carried out in another way.
• the appropriate mixing tool is selected depending on the type and size of the spherical particles used (heat transfer medium) and / or on the type and size of parts of the polymer material.
• the polymer material can be processed in different ways before being introduced into the reactor, in particular divided into pieces and / or shapes of different sizes.
• a common and suitable process is the shredding of larger parts of the polymer material into pieces with dimensions of a few millimeters to several centimeters. Due to the spherical particles, the depolymerization can be carried out with good yields and high purity with different sizes and shapes of the polymer material.
• FIG. 2 shows an alternative embodiment of the reactor, namely a reactor 51 with a vertically oriented rotating shaft 53 and with a plurality (here three) of shovel-shaped mixing tools 63 which attach directly to the shaft 53 and project from the shaft 53 in the radial direction.
• the linear rectilinear representation of the mixing tools 63 is to be understood schematically.
• the mixing tool 63 can be curved in the vertical and / or horizontal direction.
• FIG. 2 shows (for reasons of clarity of illustration only in one of the three sectors of the reactor 51 subdivided by the mixing tools 63) a moving material 65 moved by the mixing tools 63 with pieces of polymer material 66 and balls 67. Because of their shape, the balls 67 can easily move move against each other and relative to the pieces of polymer material 66. There is therefore no mechanical snagging or jamming within the material to be moved 67. In order to ensure particularly good mobility within the goods to be moved, it is preferred that the total volume of the balls in the reactor is greater than the total volume the still solid pieces of polymer material, in particular at least twice as large. Baking or snagging of the pieces of polymer material together is thus largely avoided.
• the reactor 51 has an electrical heater 59 at least on the side of the reactor wall.
• the lateral reactor walls and the base are preferably heated essentially over the entire surface and / or by means of a heating device distributed uniformly along the wall surface.
• a heating device distributed uniformly along the wall surface.
• B a conventional electrical resistance heater and / or an inductively acting heating device.
• the circular outer jacket of the reactor 1 is heated over the entire surface by a heating device 9.
• the shaft 3 can be combined with a shaft cooling 5.
• the MMA / protective gas mixture is passed into a cooling device 33 (for example a quencher), in which the still hot gas mixture is sprayed with a portion of previously cooled and recirculated condensate by means of a nozzle as in a shower and in a very short time Time is cooled.
• a cooling device 33 for example a quencher
• the cooling device 33 is connected via a monomer drain 35 to a monomer container 37, into which the cooled monomer is drained.
• a pump 41 part of the monomer located in the monomer container 37 is returned via a return line 40 to the nozzle of the height device.
• a continuous cooling device 43 is located in the return line 40.
• the monomer is driven out of the system by a pump 39.
• An additional return to the cooling device 33 is possible through a connecting line connected to the line 38, which can be shut off by means of a valve 47.
• the other end of the connecting line 46 is connected to that part of the return line 40 which lies in the flow direction beyond the continuous cooling device 43.
• the resulting temperature at the nozzle of the cooling device 33 can be controlled via the control of the valve 47 and a corresponding mixture of recycled monomer of different temperatures.
• FIG. 5 shows a lock device 22 which can be connected upstream of the reactor 1, for example in the arrangement according to FIG. 1.
• a filler neck 20, which, for example, is attached to the metering device 21 shown in FIG. 1, opens into the lock chamber 19 of the lock device 22 can close the filler neck 20 by means of a reciprocating closure part 80.
• the locking device 71 is designed such that the lock chamber can be closed gas-tight on the entry side.
• a second closing device 72 which, for example, can also close a polymer feed line 17 to the reactor via a back and forth movable closure part 81.
• the second closing device 72 is also designed such that it can close the container 19 (here on the outlet side) in a gas-tight manner.
• a gas line 74 which is combined with a main valve 78, also attaches to the lock chamber 19. From the view of the lock chamber 19, beyond the main valve 78, there is a T-piece 75, on which the gas line 74 branches into an upper branch and a lower branch.
• a pump 76 is arranged in the upper branch.
• a protective gas valve 79 is arranged in the lower branch.
• the lower branch opens, for example, into the protective gas feed line shown in FIG. 1.
• the upper and lower branches do not have to lead up or down as shown in the figure, but can lead in any suitable direction.
• protective gas is then introduced into the lock chamber 19 up to a desired pressure.
• a final pressure in the lock chamber 19 is preferably reached which is higher than the pressure of the protective gas in the reactor. In this way, losses of protective gas from the reactor can be compensated for by discharging the monomer / protective gas mixture from the reactor and, on the other hand, the monomer / protective gas mixture can be prevented from flowing out through the polymer feed line into the lock chamber 19.
• the second, lower closing device 72 is opened and the quantity of polymer material is thus introduced into the reactor.
• Example 1 A vane reactor with a diameter of 280 mm and a length of 400 mm was chosen. Twelve kilograms of steel balls with a diameter of 0.2 mm were filled into this reactor as a heat transfer medium. During the depolymerization, the mean sphere temperature was 456 degrees Celsius, the excess pressure of the protective gas in the reactor (nitrogen in the example), based on atmospheric pressure at sea level, and 66.7 hPa (approx. 50 Torr), and the speed of the shaft of the blade reactor 100 rpm. With a plant structure as shown in FIG. 1, a yield of MMA of 97% with a purity of 98.5% was achieved.
• Example 2 The procedure was as in Example 1, but twenty kilograms of the steel balls were introduced into the reactor and an average ball temperature of 380 degrees Celsius was set. The MMA yield was 98% with a purity of 99%.
• Example 3 The test was carried out as described in Example 2, but the process was carried out at an average ball temperature of only 320 degrees Celsius.
• the MMA yield was 98.5% with a purity of 99%.

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• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
• Physical Or Chemical Processes And Apparatus (AREA)

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• 2003
  • 2003-06-03 DE DE10325251A patent/DE10325251A1/de not_active Withdrawn
• 2004
  • 2004-03-20 WO PCT/EP2004/002954 patent/WO2004106277A1/de active Application Filing
  • 2004-03-20 BR BRPI0411093-5A patent/BRPI0411093A/pt not_active Application Discontinuation
  • 2004-03-20 EP EP04722182A patent/EP1631538A1/de not_active Withdrawn
  • 2004-03-20 CN CNB2004800184851A patent/CN100415708C/zh not_active Expired - Fee Related
  • 2004-03-20 MX MXPA05013109A patent/MXPA05013109A/es active IP Right Grant
  • 2004-03-20 JP JP2006508139A patent/JP2006526582A/ja active Pending
  • 2004-03-20 CA CA002527969A patent/CA2527969A1/en not_active Abandoned
  • 2004-03-20 RU RU2005141291/04A patent/RU2355675C2/ru not_active IP Right Cessation
  • 2004-03-20 KR KR1020057023205A patent/KR20060021342A/ko not_active Application Discontinuation
• 2005
  • 2005-12-02 ZA ZA200509808A patent/ZA200509808B/xx unknown

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