PHOTOREACTOR AND PHOTOREACTOR SYSTEM WITH PHOTOREACTOR

Description

[0001] The invention relates to a photoreactor system with a photoreactor for radiation-induced reactions in a medium, the photoreactor comprising (i) a sleeve-like base body extending along an axis, (ii) a plurality of LED lighting elements arranged circumferentially around the axis on the inner circumference of the sleeve-like base body, and (iii) a free space circumferentially surrounded by the LED lighting elements for at least one reaction vessel for statically receiving the medium and / or for dynamically guiding the medium.

[0002] Publication WO 2017 / 181125 A1 discloses a photoreactor, specifically designed as a photocatalytic reactor for water treatment, comprising (i) a sleeve-like base extending along an axis, (ii) several LED light sources arranged circumferentially around the axis on the inner circumference of the sleeve-like base, and (iii) a space completely enclosed by the LED light sources, in which a reaction vessel for dynamically guiding the medium is located. Both the LED light sources and the reaction vessel are fixed in place.

[0003] Besides such practical applications, laboratory applications are also gaining increasing importance. Due to the use of light (photons) as an environmentally friendly and sustainable activation reagent, photoredox catalysis has attracted growing interest in various areas of organic and polymer chemistry in recent years. Currently, photoredox catalysis is considered a central branch of current research. However, carrying out such reactions requires specialized equipment. This equipment has so far been associated with high investment costs or a disproportionately large volume of equipment. Consequently, such equipment is only available in a few laboratories.

[0004] Documents US 2015 / 314024 A1, DE 10 2014 012219 A1, US 2013 / 026682 A1, US 2015 / 175531 A1, WO 98 / 46933 A2, US 4 482 809 A and US 2003 / 232540 A1 describe further photoreactors of the type mentioned for a wide variety of applications. EP 3 126 052 A1 describes a system for biochemical reactions.

[0005] The object of the invention is to provide a photoreactor system in which the photoreactor can be flexibly adapted to individual requirements, especially in laboratory applications.

[0006] The problem is solved according to the invention by the features of independent claim 1. Preferred embodiments of the invention are specified in the dependent claims, each of which can represent an aspect of the invention individually or in combination.

[0007] In the photoreactor system according to the invention, comprising a photoreactor for radiation-induced reactions in a medium, which (i) has a sleeve-like base body extending along an axis, (ii) has a plurality of LED lighting elements arranged circumferentially around the axis on the inner circumference of the sleeve-like base body, and (iii) has a free space circumferentially surrounded by the LED lighting elements for at least one reaction vessel for the static reception of the medium and / or for the dynamic guidance of the medium, it is provided that the photoreactor system has a set of retaining elements for holding differently designed reaction vessels for the static reception of a medium and / or the dynamic guidance of a medium.Each of the retaining elements from the set of retaining elements for holding the at least one reaction vessel into the free space can be detachably attached to one end of the base body via a bayonet locking mechanism. The photoreactor has a compressed air cooling device for the LED lighting elements, operating with air as the cooling fluid, with cooling channels for the cooling fluid formed in the sleeve-like base body.

[0008] In other words, the at least one reaction vessel held by the respective holding element extends into the free space, whereby reaction vessels of various designs are held into the free space by a set of holding elements, which constitutes the flexibility of this photoreactor or photoreactor system with photoreactor and set of holding elements.

[0009] In particular, it is provided that the retaining element is designed as a cover element, which closes the free space at one end.

[0010] It is advantageously provided that one end of the base body is formed by a support element. This support element is attached to the head end of the remaining part of the base body, in particular by a detachable attachment. The support element thus acts as a kind of lid for the base body, closing it at one end.

[0011] According to the invention, the retaining element is attached to one end of the base body, specifically to the support element, via a bayonet locking mechanism. A bayonet lock is a mechanical connection between two parts that can be quickly assembled and disassembled. The parts are connected and separated by inserting connecting elements into one another and rotating them in opposite directions about a longitudinal axis. The connecting elements have connecting structures to form a projection-recession arrangement. The retaining element has corresponding projection or recession structures. The end of the base body has corresponding recession or projection structures. The embodiment of the bayonet lock used preferably here is known, for example, from cameras.

[0012] According to the invention, the photoreactor has a cooling device for the LED lighting elements with cooling channels formed in the sleeve-like base body for a cooling fluid of the cooling device.

[0013] The cooling system is designed to be a compressed air cooling system. With air as the coolant / cooling fluid, no major problems arise in the event of a leak.

[0014] According to a further preferred embodiment of the invention, a bottom element of the photoreactor is arranged at the other end of the sleeve-like base body, closing the free space at this other end.

[0015] In particular, it is provided that a distribution system for distributing the cooling fluid to the cooling channels is formed in the base element.

[0016] According to a preferred embodiment of the invention, the cooling device provides for at least one flow path for the cooling fluid, in which the cooling fluid is initially guided past at least one of the LED light sources in the flow direction to cool it, and then passes through the free space. In particular, the cooling fluid is guided via the base element onto at least one support that carries / holds the LED light sources and is then conveyed further into the reactor interior, where it enters the free space to cool the reaction vessel or at least one of the reaction vessels. Furthermore, the photoreactor also has an outlet for the cooling fluid. This is preferably located at one end of the reactor. The cooling fluid is—as already mentioned—primarily compressed air.

[0017] According to a further preferred embodiment of the invention, the sleeve-like base body is a base body manufactured by 3D printing and / or the bottom element is a bottom element manufactured by 3D printing.

[0018] According to a further preferred embodiment of the invention, the photoreactor further comprises a tubular reflector screen arranged between the LED lighting elements and the free space, in which recesses are formed at the level of each individual LED lighting element.

[0019] Finally, the photoreactor also includes at least one reaction vessel itself.

[0020] The photoreactor system according to the invention, comprising a photoreactor mentioned above, therefore has a complete set of holding elements for holding different reaction vessels, wherein this set includes the holding element mentioned in connection with the photoreactor.

[0021] The invention is explained below by way of example with reference to the accompanying drawings and preferred embodiments, wherein the features shown below can represent an aspect of the invention, either individually or in combination. The drawings show: Fig. 1 a photoreactor according to a preferred embodiment of the invention in an exploded view, Fig. 2 six detachable retaining elements for holding different types of reaction vessels, Fig. 3 a floor element of the in Fig. 1 The photoreactor shown in a partial sectional view and Fig. 4 further details of a basic body of the in Fig. 1 shown photoreactor.

[0022] The Fig. 1 Figure 10 shows a modular photoreactor 10 for radiation-induced reactions in a medium in an exploded view. This photoreactor 10 comprises the following components: a sleeve-like base body 14 extending along an axis 12, one end 16 of which is formed by an annular support element 18, a base element 22 closing the other end 20 of the sleeve-like base body 14, a plurality of LED light sources 24 arranged circumferentially around the axis 12 on the inner circumference 26 of the sleeve-like base body 14, an axial free space 28 surrounded circumferentially by the LED light sources 24 for at least one reaction vessel 30 for statically receiving the medium and / or for dynamically guiding the medium, a sleeve-shaped reflector screen 32 arranged between the LED light sources 24 and the free space 28, in which recesses 34 are formed at the level of each individual LED light source 24, through which the LED light sources 24 can illuminate the free space 28,and a retaining element 36 that can be detachably attached to one end 16 of the base body for holding the at least one reaction vessel 30 into the free space 28.

[0023] The retaining element 36 has retaining structures 38 for the reaction vessel(s) 30 and is designed as a lid element 40 that closes the free space 28 at one end 16. The retaining element 36, designed as a lid element 40, is detachably attached to one end 16 of the base body 14 (formed by the support element 18) via a bayonet locking mechanism 42. The support element 18 and the retaining element 36 are connected and separated by the locking mechanism 42 by inserting them into one another and rotating them in opposite directions with respect to the axis 14. The two elements 18 and 36 have connecting structures 44 and 46 to form a projection-rear grip arrangement. The support element 18 has rear grip structures 44 at one end 16 of the base body 14, and the retaining element 36 has corresponding projection structures 46.

[0024] The LED light sources 24 are interchangeably attached to the inner circumference 26 of the sleeve-like base body 14. Each of the LED light sources 24 required for a photoreaction is placed on a respective carrier 48, resulting in LED arrays 24, 48. These can therefore also be referred to as interchangeable LED light sources or LED light source modules 24, 48.

[0025] Photoreactor 10 also features a cooling device for the LED lighting units 24, which can be seen in Fig. 1 However, only a cooling fluid inlet 50 on the base element 22, coolant passages 52 from the base element 22 to the main body 14, and cooling fluid outlets 54 in the support element 18 can be identified. Corresponding cooling channels for the cooling fluid formed in the sleeve-like main body 14 are not directly visible. A distribution system for distributing the cooling fluid to the cooling channels is formed in the base element 22. The cooling device is a compressed air cooling device, thus using (compressed) air as the cooling fluid. In order to create the sleeve-like main body 14 and the base element 22 with the corresponding channels, these components 14 and 22 are manufactured using a 3D printing process in this example.

[0026] In a slightly modified cooling device, this cooling device forms flow paths for the cooling fluid, in which the cooling fluid is first guided past the LED lighting elements 24 by their associated supports 48 in the direction of flow to cool these lighting elements 24, and then additionally passes through the free space 28 to cool the reaction vessel 30 or reaction vessels 30. Furthermore, the photoreactor 10 also has at least one outlet for the cooling fluid, through which the cooling fluid leaves the photoreactor 10. This outlet is preferably located at one end of the photoreactor 10.

[0027] The in Fig. 1 The modular design of the photoreactor 10 shown allows for the simple and cost-effective replacement of the components to be adapted, LED lighting body 24 and holding element 36, while the rest of the photoreactor 10 remains unchanged.

[0028] In contrast to other photoreactors 10, the photoreactor system shown here focuses specifically on the adaptability of the components most important for photoreactions – the illumination and the reaction control method. The modular design allows for the simple and cost-effective replacement of the components 24, 30 requiring adaptation, while the rest of the reactor system remains unchanged. In addition to the ability to adjust the LED illumination elements 24 with regard to their wavelength, light intensity, and dimensions to meet specific requirements, it is possible for the first time to carry out both batch and continuous reactions in the same photoreactor 10. Due to the adaptability of the photoreactor system, expansions of its functionality can be implemented in a time- and cost-efficient manner.

[0029] Possible expansion (in Fig. 1 (not shown) e.g. (i) measuring light intensity using an external radiometer, or (ii) using a cuvette as a reaction vessel (in Fig. 3 (shown) for reaction monitoring using UV / Vis. The photoreactor 10 is extended with the corresponding components for this purpose.

[0030] For the sake of simple and cost-effective manufacturing, the majority of all components are designed as 3D-printed parts. The photoreactor 10 shown here is a novel reactor 10 for carrying out photocatalytic reactions on a laboratory scale. It offers the user a new and attractive way to safely, reproducibly, and adaptively perform photocatalytic reactions.

[0031] The photoreactor 10 consists of the aforementioned components, which are fastened together by simple and robust screw and / or plug connections, as shown in Fig. 1 The LED light sources 24 required for a photoreaction are shown here in an example placed on a total of six carriers 48 (LED arrays). The carriers 48 are dimensioned to accommodate a wide variety of LED light source designs 24. In addition to cost-effective LED strips, the use of high-performance SMD LEDs is also planned. Despite their high efficiency (around 40-50% for current models), LEDs convert some of their electrical power into heat. This heat must be dissipated effectively, not only to protect the LEDs from overheating but also to prevent uncontrolled heating of the reaction medium. For effective heat dissipation, the carriers 48 are made of aluminum, a lightweight material with high thermal conductivity. Additionally, the operating temperature of the LEDs is kept constant by a targeted airflow from the compressed air cooling system.

[0032] The LED arrays 24, 48, i.e., the carriers 48 with the LED light sources 24, are subsequently inserted into the base body 14. This allows for both quick replacement of the carriers (circuit boards) 48 and reproducible fixation of the light sources 24. The use of a total of six carriers 48 along the edges of a hexagon ensures a homogeneous light distribution within the reactor volume, i.e., the free space 28. For efficient energy utilization, it is advisable to reflect all photons that do not directly strike the reaction medium back onto it. The reflector screen 32 is provided for this purpose. It has a reflective or diffusely reflective surface on its inner side, resulting in a more homogeneous illumination field. Furthermore, the reflector screen 32 defines a closed control chamber, which enables a complete photon balance to be performed.

[0033] To ensure compatibility between the photoreactor 10 and a variety of magnetic stir plates with different diameters, it has 20 adjustable mounting clamps 56 at its other end, which serves as the underside. These clamps are attached to the base element 22 via screws 58. The mounting clamps 56 can be adjusted according to the magnetic stir plate used, thus guaranteeing a reproducible position on the stirrer and a secure hold.

[0034] The ring-shaped support element 18 at one end 16 of the sleeve-like base body 14 is detachably attached to a base unit of the base body 14 via magnetic fasteners 60. The support element 18 thus acts as a kind of cover for the base unit of the base body 14.

[0035] The photoreactor 10 can be flexibly adapted to the desired reaction conditions by means of a two-part housing cover 18, 36 formed by the support element 18 and the retaining element 36, which serves as the cover element 40. The two elements 18, 36 are detachably connected to each other by a bayonet fitting. The inner part of the cover 18, 36, namely the retaining element 36, provides the interchangeable functionality for the reaction vessel 30, and the outer part of the cover 18, 36, namely the support element 18, provides the interchangeable functionality for the LED arrays 24, 48.

[0036] The Fig. 2 Figure 1 shows various embodiments of these retaining elements 36, which are designed as lid elements 40. In addition to a retaining element 36 for a single batch reaction, i.e., with a retaining structure 38 for a single reaction vessel for the static holding of the medium 62, a retaining element 36 for a multi-batch reaction for up to six reaction vessels, i.e., with several retaining structures 38 for several (here six) reaction vessels 30, is also shown. Fig. 2 (First four examples on the left). The system is currently compatible with all standard sample bottles (3-10 ml). Expanding compatibility requires only an adjustment of the retaining element 36. Because the lid 18, 36 is divided into two components, only the inner part 36 needs to be redesigned and manufactured to adapt the functionality. This minimizes material usage and manufacturing time. Manufacturing a new retaining element 36 (functional lid) takes an average of two hours.

[0037] In photochemistry, continuous reactions offer numerous advantages over conventional batch reactions. Continuous processes not only achieve higher throughputs but also ensure safe handling of the reagents and more efficient irradiation of the medium (due to the reduced layer thickness). For this purpose, the presented photoreactor 10 enables users to easily transition to continuous reaction operation. Instead of the reaction vessels used in batch processes for the static holding of the medium 62, a further holding element 36 is used ( Fig. 2 - 2 (from the right) an optically transparent capillary is used as a reaction vessel for the dynamic guidance of medium 64. This means that the scaling step from a batch reaction to a continuous process does not require a new reaction setup, and a direct comparison of both reaction processes is possible. On the far right is in Fig. 2 A holding element 36 with a holding structure 38 for a reaction vessel 30 designed as a cuvette 66 is shown.

[0038] The Fig. 3 Figure 1 shows a partial sectional view of a base element 22 of the photoreactor 10. In this view, in addition to the cooling fluid inlet 50, a distribution system (also called a cooling fluid flow divider) 68 formed in the base element 22 is also visible. The cooling fluid inlet 50 can be considered an inlet nozzle with an adjoining inlet channel extending to the center of the base element 22. The distribution system 68 has distribution channels 70 extending from the end of the inlet channel, which open into the cooling fluid passages 52. These are—as mentioned—the starting point for the cooling channels formed in the base body 14, which in turn pass through the supports 48 and open into the cooling fluid outlets 54. By means of this distribution system 68, called the "airflow divider," a single compressed air flow is evenly divided among six channels 70 and directed over the rear faces of the supports 48.Only through a build-up method, such as 3D printing, is the production of such internal channel structures possible.

[0039] The Fig. 4 Figure 1 shows further details of the base body 14. On the inner circumference 26 of the base body 14, support receptacles 72 are formed in the form of insertion rails into which the supports 54 can be inserted from one end 16. Viewed from the free space 28, a corresponding cooling channel runs behind each support receptacle 72 (with the support 48 inserted), extending from an associated cooling fluid passage 52 to the corresponding cooling fluid outlet 54.

[0040] The dimensions (150 x 150 x 80 mm, 1.8 l) and weight (250 g) of the photoreactor 10 from the example shown here allow for easy transport. The photoreactor 10 is therefore a portable photoreactor 10. Existing photoreactors 10 were developed either only for batch reactions or only for continuous reactions. The use of a flexibly adaptable photoreactor 10, or a photoreactor system with a photoreactor 10 and various support structures 38 and reactor vessels 30, and the associated integration of batch and continuous reaction control into the same system, is entirely new. The photoreactor 10 shown here, or the associated photoreactor system, provides a setup that, due to its low production costs and adaptability, can be used as basic equipment in a wide variety of laboratories. Bezugszeichen

[0041] 10 Photoreactor 12 Axis 14 Base body 16 One end 18 Support element 20 Other end 22 Base element 24 LED lighting body 26 Inner circumference 28 Clearance 30 Reaction vessel 32 Reflector screen 34 Recess 36 Retaining element 38 Retaining structure 40 Lid element 42 Bayonet locking mechanism 44 Rear grip structures 46 Projection structure 48 Support 50 Cooling fluid inlet 52 Cooling fluid passage 54 Cooling fluid outlet 56 Mounting clamp 58 Screw connection 60 Magnetic attachment 62 Reaction vessel for static medium holding 64 Reaction vessel for dynamic medium guidance 66 Cuvette 68 Distribution system (cooling fluid flow divider) 70 Cooling channel 72 Support mount

Claims

1. A photoreactor system comprising - a set of holding elements (36) for holding differently configured reaction vessels (30) for the static reception of a medium and / or for the dynamic guidance of a medium, and - a photoreactor (10) for radiation-induced reactions in the medium, which has a sleeve-like base body (14) extending along an axis (12), a plurality of LED lighting bodies (24), which are arranged on the inner circumference (26) of the sleeve-like base body (14) circumferentially around the axis (12), and a free space (28) circumferentially surrounded by the LED lighting bodies (24) for at least one of the reaction vessels (30), wherein each of the holding elements (36) from the set of holding elements (36) is detachably attachable for holding the at least one reaction vessel (30) into the free space (28) via a bayonet locking mechanism (42) at one end (16) of the base body (14), and wherein the photoreactor (10) has a compressed air cooling device (50, 52, 54) for the LED lighting bodies (24) that operates with air as the cooling fluid, with cooling channels for the cooling fluid formed in the sleeve-like base body (14).

2. The system according to claim 1, characterized in that the holding elements (36) from the set of holding elements (36) are configured as cover elements (40) closing the free space (28) at the one end (16).

3. The system according to claim 1 or 2, characterized in that a bottom element (22) of the photoreactor (10), which closes the free space (28) at this other end (20), is arranged at the other end (20) of the sleeve-like base body (14).

4. The system according to claim 3, characterized in that a distribution system (68) of the cooling device for distributing the cooling fluid to the cooling channels is formed in the bottom element (22).

5. The system according to any one of claims 3 to 4, characterized in that the cooling device (50, 52, 54) forms at least one flow path for the cooling fluid, in which the cooling fluid, in the direction of flow, is first guided past at least one of the LED lighting bodies (24) for cooling the latter and subsequently passes through the free space (28).

6. The system according to any one of claims 1 to 5, characterized in that the sleeve-like base body (14) is a base body (14) manufactured by a 3D printing method and / or that the bottom element (22) is a bottom element (22) manufactured by a 3D printing method.

7. The system according to any one of claims 1 to 6, characterized in that the photoreactor (10) has a tubular reflector screen (32) arranged between the LED lighting bodies (24) and the free space (28), in which recesses (34) are formed at the level of each individual LED lighting bodies (32).