WO2015078908A1

WO2015078908A1 - Method for carrying out chemical reactions

Info

Publication number: WO2015078908A1
Application number: PCT/EP2014/075654
Authority: WO
Inventors: Karl Gruber; Arne Gerhardsen; Turid GERHARDSEN
Original assignee: ATG Entwicklungsgesellschaft GmbH
Priority date: 2013-11-27
Filing date: 2014-11-26
Publication date: 2015-06-04
Also published as: DE102013019949A1

Abstract

The invention relates to a method for carrying out a chemical reaction between a target gas and a molecular beam using an ultrasonically generated "stationary wave", and to a method for carrying out said method.

Description

A method for carrying out chemical reactions

The invention relates to a method for carrying out a chemical reaction between a target gas and a molecular beam by means of a "standing wave" generated by ultrasound and to a reactor for carrying out this method.

Theoretical background

Heat energy can be understood as the undirected kinetic energy of molecules. The description of heat, taking into account the motion of individual molecules or their statistical consideration, is given in kinetic gas theory (or statistical thermodynamics).

The basic theories of statistical thermodynamics were discussed more than 100 years ago. developed in Vienna by Ludwig Boltzmann and since then form a mainstay of physical chemistry.

The kinetic theory of gases shows the relationship between the energy content and the velocity distribution of the atoms or molecules in chemical systems. Especially vivid is the consideration of ideal gases.

From these considerations, for example, the theoretical relationship between heat capacity of a molecule c _v ; c _p and the number of degrees of freedom for the movements of this molecule.

In a gas-filled, closed container (with defined temperature and pressure), for example, a linear molecule of composition ABA can move linearly in 3 spatial directions, it can freely rotate at least about 2 axes (rotation in the axis does not absorb rotational energy) and at least 2 oscillations (symmetric stretching vibration, asymmetric stretching vibration). If an energy of 1/2 kT is assumed for each degree of freedom, the translucency of the molecule is 3/2 kT for the rotation component 2/2 kT and for the vibration component 2 / 2kT.

The velocity of the gas molecules in the container is subject to a statistical distribution - the Maxwell Boltzmann distribution. An increase in temperature corresponds to an increase in the average velocity of the gas molecules. Accordingly, the number of Wall collisions on the container multiplied, which is macroscopically observed as an increase in gas pressure. The time between two bursts is the longer the slower the molecules fly and the less impact partners are in the area. At the macroscopic level, this time is determined between two bursts of T, p and n (number of particles per volume). The path between bumps is called the free path length and the number of bumps per second is called the bump number. In addition to these two sizes, the size of the molecules also plays a role. The "size" of the molecules is usefully described by the so-called collision cross-section, which can be much larger than the dimensions of the neutral molecule as soon as it is ionized (carrying an electric charge).

From the classical relationship for the kinetic energy E _kin = mv ^2/2 it can be seen that the kinetic energy of a molecule is determined not only by its velocity but also by its mass. Thus, a heavy molecule naturally has more kinetic energy than the light molecule at the same rate.

From molecular beam experiments it is known that in principle there are the following kinds of collisions between particles: elastic shock; inelastic shock; reactive shock; When fully elastic shock holds the pulse conservation law. This is in principle conceivable only for particles without structure. Inelastic collision transforms "external energy" (T) partially or wholly into "internal energy" of molecules (R-rotation, V-vibration / vibration). In the reactive collision, the transformation of T into R and V results in the formation of a stable "transition state" for a fraction of a second, during which the actual (chemical) rearrangement of the atoms and formation of new chemical bonding conditions takes place in that in the case of the elastic shock the time in which the impact takes place is measured in picoseconds (10 ^"12 s), in the case of an inelastic or reactive impact the time span is orders of magnitude longer and lies in the range of one rotation period of a molecule in nanoseconds ( 10 ^"9 s).

It is known from general chemical practice that chemical reactions are highly pressure and temperature dependent. An interpretation of this fact at the molecular level suggests that by increasing the parts of translation, rotation and vibration, the individual molecules become more energetic (excited) and thus easier to react or dissociate.

From the study of the reaction mechanisms it is also known that in a chemical reaction in the 3 partners meeting eg: AB + C - AC + B, the molecule AB does not have to dissociate in a first step, but a transitional state according to AB + C - [AB-C] * - AC + B. The reaction can thus be simplified as follows: The molecule AB and the molecule C approach each other until the "chemical forces" are sufficient for a "high-energy transition state" to build. In this transitional state the atoms regroup. Subsequently, the reaction products fly away from each other again.

In any case, the molecules that meet in the chemical reaction must bring enough energy to overcome existing energetic reaction barriers (thresholds). This energy can basically bring the molecules as "external energy" or "internal energy". Under external energy is here the translation component T understood under internal energy, the rotational component R and the vibration component V (Vibrational States).

The chemist has previously known the following methods to excite molecules, i. to give them energy:

- increase in temperature (supply of heat energy / supply of undirected translation ^ increase of external and internal energy)

- pressure increase (shortening of the free path length / increase of the density increase of external and internal energy)

- Targeted vibration excitation (supply of electromagnet energy / photoreactions - increase of internal energy)

- Targeted supply of electrons / electrode reactions (electrochemistry) ^ Increase of internal energy

From chemical practice it is known that in a chemical reaction usually only a certain part of the starting materials is transferred into the products (according to the adjusting chemical equilibrium). In this context we speak of yield. A simplifying explanation from the statistical point of view provides the regularities of the energy distribution of the individual molecules (macroscopic rate constants). There is always a wide distribution here. Only molecules with just the right energy content (if the steric aspects remain excluded for the time being) are able to carry out the chemical reaction. Molecules that have too much or too little energy (or are sterically hindered) will not lead to a successful chemical reaction.

A theoretical consideration would be to artificially narrow the velocity distribution in such a way that only the type of energy-rich molecules is formed which are suitable for carrying out a chemical reaction. If 100% of the considered molecules are so-targeted Translation could be excited, then the yield of a subsequent reaction would have to be at 100%.

Experience has shown that this can not be achieved with any of the abovementioned methods; a chemical equilibrium always always arises between educts and products, which is described macroscopically via the rate constants (kinetics).

A deliberate narrowing of the statistical distribution of the energetic state, which affects all molecules considered, is the relaxation of a pressurized gas through a nozzle.

In general, the nozzle is a means to convert pressure almost lossless into speed.

From the physical chemistry is known in this context, the so-called. Joule Thomson effect. A gas flowing out of a vessel via a nozzle with overpressure, for example at supersonic speed, cools down and the velocity distribution of the molecules is greatly restricted (and shifts to higher values compared to the velocity distribution in the vessel). This is the basis of the liquefaction of gases (Linde process etc.). On the microscopic side, the molecules in the nozzle lose on the one hand 2 degrees of translational freedom (non-directional T becomes directed T), on the other hand the molecules lose their rotational part R mainly due to internal energy. The rotational levels fully occupied at room temperature are emptied and can be rotated at an average nozzle pitch correspond to a gas of a temperature of only 5K. This is due to the directed collisions of the molecules with each other in the nozzle. As a result, the physical repulsion of the molecules is abolished and the molecules aggregate into larger aggregates. The forces acting between the molecules are called van der Waals forces.

If the nozzle jet hits a vessel in which vacuum (vacuum) prevails, the van der Waals forces predominate. The molecules are initially bound to dimers, later to larger ones

Aggregates together and it can ultimately come to a liquefaction. Meets that

Jet into an area where many gas molecules are present (e.g.

Ambient pressure), so the molecules collide from the beam - which have a lot of external energy but less internal (especially R) - with the "thermally in equilibrium

Molecules "and there is an exchange of energy between these molecules: the so-called.

Relaxation. In this case, the directional translation of jet jet molecules by collisions with the thermally equilibrium molecules in the vessel rapidly becomes undirected translation. The proportion of rotation also increases rapidly again. The result is an increase in undirected translation in the chamber - that is, an increase in heat.

A Simple Consideration of an Endergonic Reaction - e.g. To initiate the homolytic cleavage or a dissociation of a stable molecule would now be targeted to shoot a nozzle jet with high translational energy against a wall in the hope that the "überhermische translation portion" wall wall redistributed so in internal energy that the molecule In practice, however, this is not observed because the molecules are thrown back in the form of an elastic or inelastic wall impact, and in the case of an elastic impact the backscattering leads to disordered translation and rotation (increase in heat) in the case of an inelastic collision They additionally energy to the vessel wall.

Another consideration would be to align two jets with each other in the hope that high - energy molecules will meet and thus produce a "reactive shock." In practice, such things can be observed in so - called molecular beam experiments, where atoms or molecules of the same (or different types) are observed ) accelerated in two nozzles and shot at each other in so-called "crossed molecular beams". From the analysis of the reaction products by means of MS (mass spectrometer) or laser spectroscopy in the picosecond range, the "molecular processes" during the collision can be observed.The deflection and angular distribution of the reaction products also provide important information about the collision process Presence of a good vacuum in the reaction space, since otherwise the molecular beams would collide with other molecules than the "target molecules" and would thus "relax".

With this technique reaction products can be observed by targeted acceleration of the reactants in the over-thermal range, which can be produced under macroscopic conditions hardly or only at extreme pressure and temperature conditions. (For example, noble gas compounds). It has been observed that there are reactions with threshold and those without threshold. A typical reaction with a threshold is an endergonic reaction, (ie a reaction in which the free Gibb ^'s standard formation enthalpy is greater than zero (AGr> 0) - so it would spontaneously run in the opposite direction) with the additional binding energy required over the " over thermal "translation energy is provided in the molecular beam.

It was observed for such reactions that no reaction takes place until the threshold energy is reached, but from the threshold, the reaction cross-section (ie ultimately the yield) increases with increasing translational energy. (In contrast to For example, in the case of exergonic reactions, the reaction cross-section decreases with increasing translational energy (eg, exothermic reaction with threshold)). In any case, for endergonic reactions in the molecular beam experiment, depending on the kinetic energy (or velocity) of the collision partner, partially surprising reactions or end products were detected in the MS. It appears that as the translational energy increases, new or unpredictable pathways / mechanisms occur.

In general, it has also been observed in crossed molecular beams that the yield of reactive collisions is relatively low. It is therefore rather an inappropriate method for the technical chemical synthesis. The reason for this is on the one hand the rather small "reaction cross-section" in these experiments, ie many molecules simply fly past each other without meeting each other, on the other hand there is also the phenomenon of the so-called centrifugal barrier! Simply put, two bodies that move towards each other always convert their translational energy The closer they get to rotational energy, the phenomenon has already been described by Kepler and Newton (for astronomical dimensions):

In order to bring about a reactive collision, it is necessary that not the entire translational portion of the collision partner is previously turned into rotation. At the moment of impact, there must still be enough translational proportion that is sufficient to overcome the energy threshold (ultimately leading to a "transitional state").

Object of the invention:

From the point of view of the practical chemist, it would be ideal to have a method with the least possible energy use a chemical reaction, whether endergonisch or exergonisch- perform with a yield of 100% or near 100%, without losses due to non-directed heat energy, solvent , additional chemical energy etc.

The object of the present invention is to provide such a process and a reactor prepared therefor.

The invention:

This object is achieved by a method according to the invention for carrying out a chemical reaction between a target gas and a molecular beam. This method according to the invention for carrying out a chemical reaction between a target gas and a molecular beam is characterized in that a) a first gas (target gas) is introduced into a reactor which is acoustically resonant or an acoustic resonator,

b) in this reactor filled with the first gas, a "standing wave" (in this first gas) is then produced with the aid of an ultrasonic signal source by an ultrasonic signal with an ultrasonic frequency> 16 kHz, c) subsequently into the reactor a second gas (reaction gas) is introduced in the form of a molecular beam, wherein the molecular beam strikes at least one of the ultrasonic generated "walls of the standing wave" of the first gas.

For the purposes of this invention, "target gas" is defined as a gas which is subjected to ultrasound treatment in a reactor, so that a standing "wave" arises in this "first" gas. The term "target gas" refers to the fact that a "molecular beam "(see below) is directed from a second gas (" reaction gas ") on the" target gas ", in particular on the node or the" standing wave ", which are the points of high density and high pressure of the" target gas " Each gas can be used for this purpose Examples are C0 ₂ , CH ₄ , H ₂ 0 or gas mixtures, for example from these gases.

For the purposes of this invention, it is in particular a jet of molecules of a second gas (the "reaction gas") which, usually at high speed, is conveyed from, for example, a nozzle into the Reactor registered (or blown) is thereby aligned as a beam.

"Reactor" in the sense of this invention is defined as a container in which a reaction can take place, in the specific sense of this invention it is a container in which a chemical reaction can take place. Usually, the reactor is elongated and / or has at least two reactor ends, which may be both open and closed Examples of the shape of the reactor are a pipe or a reactor The reactor can be made, for example, of metal, plastic, ceramic or composites such as concrete or a combination of these materials. "Acoustically resonant" in the sense of this invention is defined as being capable of oscillating trapped gas in such a designed space when excited at an acoustic frequency, In particular, an "acoustically resonant" reactor is constructed so as to provide a standing wave through an "ultrasonic signal source" in the "acoustically resonant" reactor. Examples of an "acoustically resonant" reactor are a tube or a "reactor" which is partially designed as a tube, or a Helmholtz resonator. In this case, an "acoustically resonant""reactor" does not have to resonate, in certain embodiments the "reactor" may resonate, in certain embodiments not.

"Acoustic resonator" in the sense of this invention is defined as a system whose interior is tuned to a certain frequency, that gas trapped in this "acoustic resonator" vibrates when excited at this frequency. In particular, the "acoustic resonator" is constructed so as to generate a standing wave in the "acoustic resonator" by an "ultrasonic signal source." Examples of an "acoustic resonator" in the form of the reactor are a tube or a reactor partly as a tube is executed, or a Helmholtz resonator. In this case, an "acoustic resonator" does not have to resonate In certain embodiments, the "acoustic resonator" may resonate, not in certain embodiments.

"Ultrasonic signal source" in the sense of this invention is defined as a mechanical or electromechanical means with which an ultrasound signal is generated, for example a Galton whistle, ultrasound siren, lip whistle, Hartmann generator, oscillating rods, vibrating strings or a device that detects ultrasound magnetostrictive or piezoelectric generated.

"Ultrasonic signal" in the sense of this invention is defined as an acoustic signal in the form of ultrasonic waves in a frequency between 16 kHz and 1000 kHz, in particular between 16 kHz and 500 kHz or 16 kHz and 100 kHz.

"Ultrasonic frequency" in the sense of this invention is defined as the frequency of an acoustic signal in the form of ultrasound waves.The "ultrasound frequency" is preferably between 16 kHz and 1000 kHz, in particular between 16 kHz and 500 kHz or 16 kHz and 100 kHz.

"Standing wave" in the sense of this invention is defined as a wave whose deflection at certain points, the nodal points, always remains at zero Superimposition of two counter-propagating waves of the same frequency and amplitude are to be construed. In the specific sense of this invention, the "standing wave" is an acoustic wave based on an "ultrasonic frequency" derived from an "ultrasonic signal source" which forms in a "target gas" in a "reactor" designed as an "acoustic resonator". In the plan view of the "reactor" filled with the "target gas", the "standing wave" represents a sequence of regions or better rings or disks of different gas density, at which the greatest density is found at the points corresponding to the nodes Rings or discs are also called "standing wave walls" below.

"Wall or walls of the standing wave" in the sense of this invention is defined as a region or a ring / disk of greatest gas density, which forms in a "standing wave". For the purposes of this invention, this is in particular a region of greatest gas density, which in a "standing wave" as an acoustic wave based on an "ultrasonic frequency" originating from an "ultrasonic signal source" in a "target gas" in an "acoustic resonator". Reactor "forms. This region or this ring of greatest gas density is found at the corresponding points with the nodes, which lie in the plan view vertically above the nodes.

"Reaction gas" in the sense of this invention is defined as a gas which triggers a chemical reaction in a "reactor". For the purposes of the invention, this is in particular a second gas which, as a "molecular beam" of molecules of this second gas (the "reaction gas") is introduced (or blown) from, for example, a nozzle into the reactor, usually at high speed. In this case, the "reaction gas" is aligned as a molecular beam so that it triggers a reaction in the first gas, the "target gas", in particular at the "nodes" of the resulting in this first gas "standing wave". In principle, any gas can be used for this, with lighter gases or mixtures with lighter gases being preferred. Examples are C0 ₂ , CH ₄ , or gas mixtures, for example, from these gases.

In a further embodiment of the method according to the invention, the second gas is introduced into the reactor in the molecular beam at a speed> 343 m / s, preferably the second gas is introduced into the reactor at a speed> 1000 m / s, in particular at a speed between 1050 m / s and 1350 m / s entered into the reactor

and or the ultrasonic frequency for generating the "standing wave" is between 16 kHZ and 1

GHz, preferably between 16 kHz and 100 kHz,

and or

the first gas (target gas) is present in the reactor at a pressure of between 1 bar to (or and) 20 bar and between 1 bar to (or and) 10 bar before the "standing wave" arises,

and / or (in certain embodiments)

For example, the chemical reaction takes place at a temperature between 1500 ° C and 3500 ° C, preferably between 2000 ° C and 3000 ° C.

However, the temperature of the reactor is preferably not increased and the thermal energy of the chemical reaction given here is contributed by the kinetic energy of the molecular beam and not by external temperature increase of the reactor or the target gas therein.

In a further embodiment of the method according to the invention

the reactor has an elongated shape with two opposite reactor ends, wherein preferably at least one reactor end is closed or at least one

Reactor end is open,

and or

if the reactor as an acoustic resonator at least partially consists of a tube, it is particularly preferably designed in the form of an acoustically resonant tube;

and or

the reactor is an acoustic resonator with two opposite reactor ends, which preferably consists at least partially of a tube and in which at least one reactor end is closed or at least one reactor end is open;

In particular, the reactor is an acoustically resonant tube with two opposite closed or open reactor ends, in which at least one reactor end is closed or at least one end of the reactor is open.

"Pipe" in the sense of this invention is defined as an elongated hollow body of approximately two-dimensional shape in two dimensions.

An example of the dimensions of the tube is a length of 1 m and a diameter of 100 mm. In a further embodiment of the method according to the invention, the reactor has at least two opposite reactor ends, wherein the ultrasonic signal source is arranged at one end of the reactor and the opposite reactor end at least partially as a vibratable membrane, preferably at least partially as a vibratable metallic membrane, in particular Cu, Ag or Au, is executed;

and or

the reactor has at least two opposite reactor ends, wherein preferably the reactor end, on which the ultrasonic signal source is arranged, is designed in the form of a loudspeaker.

"Oscillating membrane" in the sense of this invention is defined as a membrane which resonates with it upon excitation with acoustic oscillations, whereby the "oscillatable membrane" can also be embodied as a metallic membrane, for example of precious metals. In particular, the oscillatable membrane "can also occupy only part of a reactor end.

"Shape of a loudspeaker" in the sense of this invention is defined as extending from the edges of convex bulges toward the center of the reactor end, without achieving this.

Method according to one of claims 1 to 4, characterized in that both the first gas (the target gas) and the second gas (the reaction gas / the molecular beam) consists of a clean gas or a gas mixture; Preferably, the second gas (the reaction gas / the molecular beam) consists of a gas mixture, in particular the second gas (the reaction gas / the molecular beam) consists of a gas mixture of a gas of lower molecular weight and a gas of higher molecular weight.

"Clean gas" in the sense of this invention is defined as a gas of uniform chemical composition consisting of only one type of gas molecules.

"Gas mixture" in the sense of this invention is defined as a mixture of at least two different types of gas molecules, each having a uniform chemical composition.

In a further embodiment of the method according to the invention, the first gas (target gas) and the second gas (the reaction gas / the molecular beam) have the same chemical composition. In an alternative embodiment of the method according to the invention, the first gas (target gas) and the second gas (the reaction gas / the molecular beam) have a different chemical composition.

In a further embodiment of the method o according to the invention, the second gas is selected from CH ₄ or CO ₂ or a gas mixture of CO ₂ and CH ₄ , is preferably selected from CH ₄ or CO ₂ or a gas mixture consisting of 80 vol.% - 50 vol % C0 ₂ and 20 vol.% - 50 vol.% CH, "

and

o is the first gas (the target gas) selected from CH ₄ or C0 ₂ or a gas mixture of C0 ₂ and CH ₄ , is preferably selected from CH ₄ or

C0 ₂ .

An example of the selection of the gases is that the first gas (the target gas) is C0 ₂ , while the second gas (the reaction gas), which is injected as a molecular beam into the reactor, a gas mixture of C0 ₂ with an addition of 20- 50% CH ₄ is.

In a further embodiment of the method according to the invention, the second gas (the reaction gas) in the form of the molecular beam impinges on a reactor end, preferably at a reactor end of a reactor designed as a tube, perpendicular to at least one "wall of the standing wave" of the first gas (of the target gas). , or

preferably, the second gas (the reaction gas) in the form of the molecular beam at a reactor end of a reactor configured as a pipe meets at least one node of the standing wave generated in the first gas (the target gas), or

Preferably, the second gas is introduced in the form of the molecular beam parallel to the tube longitudinal axis of the reactor designed as a tube in the reactor.

In a further embodiment of the method according to the invention, the ultrasound signal is generated by means of mechanical or electromechanical means, preferably by a Galton whistle, ultrasound siren, lip whistle, Hartmann generator, oscillating rods, vibrating strings, magnetostrictive or piezoelectric, particularly preferably by an ultrasound siren. In a further embodiment of the method according to the invention, the reactor is poured into concrete. Several reactors can be poured together in concrete and / or the reactor or reactors are made of concrete and are designed as a pipe or tubes, which may be adjacent. Pouring into concrete from either one or more reactors together serves to stiffen and prevent lost radiation.

In a further embodiment of the method according to the invention, the reactor (or at least one of the reactors or at least part of the reactors) consists of metal, plastic, ceramic or composite materials such as concrete or a combination of these materials.

In a further embodiment of the method according to the invention, the second gas from a gas container in which the second gas is present with excess pressure, introduced via a nozzle into the reactor, wherein the nozzle preferably has a diameter of 0.01 mm to 1 mm, in particular a diameter from 0.2 mm to 0.4 mm.

An example of the dimensions of the nozzle used is a diameter of 0.3 mm. Should a gas mixture of CO ₂ with an addition of 20-50% CH _{4 be} selected as the second gas (the reaction gas) which is blown into the reactor as a molecular jet, then the gas container which contains this second gas before injection, for example, under a (super) pressure of 50-100 bar and the second gas is injected as a molecular beam at a speed> 1000 m / s.

"Gas tank" in the context of this invention is defined as a pressure-resistant container for receiving a gas that is able to withstand an overpressure and is gas-tight.

"Overpressure" in the sense of this invention is defined as the pressure prevailing within the "gas container" of the gas contained therein above the ambient pressure. Preferred "overpressures" are 10 bar to 100 bar.

"Nozzle" in the sense of this invention is defined as a tubular technical device which can expand or constrict According to the invention, a "nozzle" is a tubular opening with which a gas flow is deflected, or in particular pressure is transformed into kinetic energy.

Another aspect of the invention relates to a reactor for carrying out the method according to the invention. In a corresponding inventive reactor a), the reactor is designed in such a way that a "standing wave" of this first gas can be generated in a first gas (target gas) filling it with the aid of an ultrasonic signal source by an ultrasonic signal with an ultrasonic frequency> 16 kHz,

b) the reactor has an ultrasonic signal source and

c) there is an opening to the entry of a second gas.

"The reactor is designed so that in a first gas (target gas) filling it with the aid of an ultrasonic signal source by an ultrasonic signal with an ultrasonic frequency> 16 kHz, a" standing wave "of this first gas can be generated" is defined in the sense of this invention as follows In the relevant reactor, a standing wave can be generated in a first gas contained in this reactor with the aid of an ultrasonic signal with a frequency> 16 kHz.

In a likewise corresponding reactor a) according to the invention, the reactor is an acoustically resonant reactor which consists at least partly of a tube in which a "standing wave" is or can be generated. B) the reactor has an ultrasonic signal source and

c) there is an opening to the entry of a second gas.

"The reactor is an acoustically resonant reactor in which a" standing wave "is or may be generated" is defined in the sense of this invention as follows: In the reactor in question a standing wave in a reactor contained in this reactor can be detected by means of acoustic resonance Gas are generated.

It is preferred for both reactors, if a. the ultrasonic signal source is present at a reactor end and a vibratable membrane at the opposite end of the reactor and / or

b. the reactor end carrying the ultrasonic signal source is shaped in the form of a loudspeaker.

It is also preferred for both reactors if o the reactor has an elongated shape, preferably designed as a tube;

and or the reactor has two opposite reactor ends, wherein preferably at least one reactor end is closed or at least one reactor end is open;

and or

the reactor as an acoustic resonator at least partially consists of a tube, in particular preferably in the form of an acoustically resonant tube;

and or

the reactor is an acoustically resonant tube with two opposite closed or open reactor ends, in which at least one reactor end is closed or at least one reactor end is open; and or

the reactor has at least two opposite reactor ends, wherein the ultrasonic signal source is arranged at a reactor end and the opposite reactor end is at least partially designed as a vibratable membrane, preferably as a vibratable metallic membrane, in particular made of Cu, Ag or Au;

and or

the reactor has at least two opposite reactor ends, wherein the reactor end, on which the ultrasonic signal source is arranged, is designed in the form of a loudspeaker;

and or

that the ultrasonic signal is generated by means of mechanical or electromechanical means, preferably by a Galton pipe, ultrasonic siren, lip whistle, Hartmann generator, oscillating rods, vibrating strings, magnetostrictive or piezoelectric, particularly preferably by an ultrasonic siren; and or

o the reactor is poured into concrete;

and or

the reactor is made of metal, plastic, ceramic or composites such as concrete or a combination of these materials;

and or

o that the opening to the entry of the second gas is designed as a nozzle;

and or

o the second gas from a gas container, in which the second gas is present with excess pressure, is introduced via a nozzle into the reactor, wherein the nozzle preferably has a diameter of 0.01 mm to 1 mm, in particular a diameter of 0.2 mm to 0.4 mm;

and or

o the second gas is introduced in the form of the molecular beam through the opening, preferably through a nozzle, parallel to the tube longitudinal axis of the reactor designed as a tube in the reactor;

and or

o the reactor is poured into concrete or several reactors are poured together in concrete;

and or

o the ultrasonic signal source is present at one end of the reactor and a vibratable membrane at the opposite end of the reactor;

and or

o the reactor end carrying the ultrasonic signal source is shaped in the form of a loudspeaker.

In a particularly preferred embodiment of the method and the reactor, the reactor is acoustically resonant or designed as an acoustic resonator in the form of a tube (for example, a concrete cast steel pipe), for example, 1 m in length and a diameter of 100 mm. In this case, there is, for example at a reactor end, an ultrasound source such as an ultrasound siren at the reactor. This generates in the reactor located in the first gas (the target gas) a standing wave by means of ultrasound in the range of 16 to 100 kHz. This reactor end is often designed in a curved shape, similar to a speaker. The other end of the reactor is (then) preferably at least partially designed as a movable membrane made of metal, preferably of a noble metal such as copper, silver or gold.

At one end of the reactor, a small diameter nozzle, e.g. 0.3 mm diameter, the second gas (reaction gas) at high speed> 500 m / s or> 1000 m / s injected as a molecular beam. This gas is released from a gas container, which is under pressure.

The nozzle is mounted so that the molecular beam is injected exactly parallel to the longitudinal axis of the tube so that it meets the or at least on a "walls / wall" around the nodes of the resulting in the first gas "standing waves". These are the points or regions / rings of greatest pressure and greatest density of the first gas in the reactor under the conditions of the "standing wave", ie "the wall / walls of the standing wave".

In this case, the first gas is present at ambient pressure (a pressure of approximately 1 bar) in the reactor before the "standing wave" arises, for example C0 _{2 is} selected as the first gas (target gas).

The temperature of the reactor is preferably not increased and the necessary thermal energy of the chemical reaction provided by the kinetic energy of the molecular beam. An external temperature increase of the reactor or of the target gas therein does not take place.

As a second gas (the reaction gas), which is blown into the reactor as a molecular beam, for example, a gas mixture of C0 _{2 is added} with an addition of 20-50% CH ₄ . Then, the gas container containing this second gas before blowing, for example, under a (super) pressure of 50-100 bar and the second gas is injected as a molecular beam at a speed> 000 m / s.

In this constellation, in which C0 _{2 was selected} as the first gas (target gas) and a gas mixture of C0 ₂ with an addition of 20-50% CH ₄ as the second gas (reaction gas), arise at the meeting of the molecular beam from the C0 ₂ gas mixture with the "wall / walls of the standing wave" of C0 ₂ gas via the node various reaction products, such as decomposition products of C0 ₂ or mixed products, etc., such as polyoxymethylene.

Illustration: Fig. 1) shows an example of a reactor according to the invention for carrying out a method according to the invention. A list of references is at the end of the description.

Fig. 2) shows a model of the standing wave, in which the invariable nodes are shown.

Detailed description:

The invention comprises a reactor, a process for producing target molecules suitable in this reactor, and a process for bombarding these target molecules by means of directional molecular beams. These three individual steps result in a novel process with which chemical reactions can be targeted, with a high yield of products, with the most accurate metered energy input and thus with the lowest possible energy input, can be performed.

According to the invention, the first step-the provision of target molecules having a defined energy content and high density (thus high reaction cross-section) is achieved in that a space filled with the target gas is set into acoustic oscillations, preferably in the ultrasonic range. According to the invention, this space is designed in the form of an acoustic resonator which enables the formation of standing longitudinal waves. In the simplest conceivable case, this may be a tube or a so-called Helmholtz resonator. The material of this tube can be made, for example, of metal, ceramic or plastic or polypropylene and mixtures of these materials. Preferably, those materials are selected which do not undergo any further undesired reactions with the starting materials used and products that are formed (eg corrosion reactions,...). The selection of suitable Oberfiächenmaterialien in the reactor in contact with the starting materials and products is to select for each reaction which is familiar to the expert. The generation of standing sound waves in this resonator leads to the expression of stationary antinodes and nodes. In the nodes, overpressure prevails in the antinodes. Using the example of a tube which has on one side a sound source, the vibration nodes distributed along the pipe in the form of 'cross-sectional walls ". In acoustics Such walls can, for example, by so-called. ^Kundt' sche dust figures or blown smoke be made visible. In the case of Using ultrasound, very high-energy standing waves can be generated in their nodes extremely high pressures (or differently formulated - extremely high local density) - exists. The distance between these nodes is given by half the sound wavelength.

If now a supersonic jet of a gas of the same or different composition is directed into such a node, then overhermic, translationally accelerated molecules with narrow velocity distribution, which often have grown together to larger molecular groups due to the emptying of the rotational states (dimers due to effective van der Waals forces) on a "wall" of high-density gas molecules, the reaction cross-section is thus relatively high compared to crossed molecular beams.

However, it must not be overlooked in this context that these "walls", in which locally high pressure and high density prevail, exist only microscopically for a short time in a "standing wave". And only for half an oscillation period. In the next half cycle, the wall changes to a location half a wavelength away. Viewed macroscopically, however, one sees, for example. over blown smoke - all walls "at the same time" (with the distance of half a wavelength).

Considering now a molecular beam which is irradiated in the axis of a tube (by definition in the direction + x) in which a standing ultrasonic wave is irradiated, the molecular beam strikes the baffles perpendicularly (at right angles). Microscopically, the molecular beam first hits a region of lesser density -in which there are few molecules moving together in the + x direction to the next wall. At an assumed frequency of the ultrasound of 20kHz, the wall is for a maximum of t = 1 / (2 * 20000) = 25 * 10 ^"6s . Assuming that the wall exists only for about 10% during the maximum amplitude, then this still 2.5 ^* 10 ^"6 s. This is a long time compared to the time taken for an elastic or inelastic shock (10 ^" 12s or a rotation period 10 ^{" 9s} ). However, it is within the order of magnitude found in molecular beam experiments for reactive collisions (10 ^"6 s).

Behind the wall is an area of lesser density, in which the molecules move in the direction -x, however.

The necessary energy for a successful reactive shock is therefore applied in principle both by the energy in the standing US wave and via the molecular beam.

Appropriately, however, the standing wave is tuned so that the time of

Existence of a wall is sufficiently high to allow reactive shocks. In practice, frequencies between 16 and 100kHz have been found to be sufficient. The

However, the "optimal" frequency depends on the type of molecules used, the speed of sound, Temperature, etc. dependent. In addition, the type of sound generation is important because not only the frequency but also the intensity of the sound wave have an influence on the result. Thus, ultrasound sirens ideally achieve high intensities over large frequency ranges.

In addition, it may be useful to select the "target molecules" (ie the molecules for the standing wave) not just from one type of atom but from several, and it may be advantageous to introduce equally suitable stoichiometric chemical mixtures for a desired reaction.

There is also a dependence of the angle of incidence of the molecular beam on the walls of the standing wave. A similar phenomenon is known in science: the deflection of a "jet of flame" by irradiated ultrasound A flame emerging from a smooth nozzle is not deflected by an ultrasonic wave radiated perpendicularly thereto, but when the nozzle at the outlet is tapered, the flame occurs An ultrasonic wave now impinges on the flame perpendicularly deflects it, meaning that an interaction between the molecules of the flame and that of the sound occurs only if at least part of the molecules of the flame move in the same or exactly opposite direction like the propagation direction of the sound wave.

In order to accelerate heavy molecules to high velocities, the use of so-called "seeded beams" is known from molecular beam technology, where a heavy gas (in low concentration) is added to a light carrier gas, and the heavy molecules are directed in the nozzle by the light molecules They have the same velocity as the light molecules, but their higher mass gives them higher kinetic energy.

The generation of the acoustic oscillation, preferably the ultrasonic oscillation, in the reactor can be carried out by methods known from the art, such as Galton pipe, ultrasonic siren, lip whistles, reed pipes, Hartmann generator, oscillating rods, vibrating strings and electromechanical means such as magnetostrictive, piezoelectric, etc. ,

An interesting side effect in standing ultrasonic waves is the fact that all

Gas molecules follow a directed motion. There is no undirected translation, but by external forces (in this case the resonance phenomenon) a relatively high order in the system is affected. A standing ultrasonic wave has with a crystal the

Property of being able to bend light! The free rotation of molecules is pronounced in the gaseous state, only limited in the liquid state and in the solid state largely suppressed. Therefore, the free rotation of molecules in the region of the vibration nodes of the standing ultrasonic wave is probably also limited. Similar to the gas nozzle, the directed shocks in the standing ultrasonic wave will lead to a decrease in the occupation of the rotation levels. This means that the translational energy of incident molecules from the molecular beam tend not to increase the rotational levels in the target molecule but rather directly to increase the vibrational energy V. Should the radiated translational energy actually be sufficient to split, dissociate, or react a molecule without occupying the rotational levels - So a direct transition from external translation energy into internal vibrational energy, this would be a significant energy savings in the conversion of mechanical energy (translation of molecules) into chemical energy (binding forces in the molecules).

By way of example, the order of magnitude is set forth with reference to an exemplary embodiment: In a tubular reactor with a length of 1 m, diameter 100 mm, a standing ultrasound wave is generated by means of an ultrasonic siren.

The ultrasound is generated by means of ultrasound sirens in such a way that the intensity of the standing wave is sufficiently high to create stable target walls. The higher the intensity the further the deflection of the individual vibrating particles the stronger their acceleration the higher the pressure and the density in the resulting wall.

The denser the wall, the higher the "reaction cross-section" with the incident molecular beam.

The ends of the tube may be open, as an open tube end in acoustics is also known for total reflection. Preferably, however, the one end of the reactor is mounted on which the ultrasonic siren is sealed in order to avoid radiation losses. The shutter can be flat or preferably have a curved shape in order to direct the US signal in a targeted manner from the source into the interior of the reactor analogously to the loudspeaker in the acoustics. Also preferably, the other end with a vibratory closure, for example a membrane, preferably a metallic membrane, for example, a metal sheet is preferably closed from Cu.Ag.Au. This helps to improve the resonance conditions for the standing wave.

Since radiation of the ultrasound into the environment primarily means power loss, it is advantageous to design or fix the tube as rigidly as possible. In this context, it is conceivable in an upscaling of the process, the pipes individually or to pour as a bundle in a rigid concrete shell. It would also be possible to pour cheap plastic pipes in concrete or just work in concrete tubes.

The irradiation of the molecular beam via a nozzle with, for example 0.01-1 mm diameter, preferably 0.3mm diameter in the direction of the tube axis-that is perpendicular to the baffles of the standing wave. The smaller the diameter of the nozzle, the higher the achievable speed with the same admission pressure, but also the lower the throughput. The flow rate of the injected gas must be adjusted so that the resulting velocity of the gas molecules at the nozzle exit is advantageously as high as the values calculated from statistical thermodynamics sufficient to cause a reaction, for example, dissociation. The irradiated particles should advantageously have at least supersonic speed, preferably at speeds <1000 m / s.

By way of example, the dissociation of C0 _{2 is} treated. In fact, the reaction occurs at temperatures between 2000 ° and 3000 ° C. According to the central formula of the kinetic gas theory c _RM s = SQR (3RT / M _M ) (where RMS stands for Root mean Square, or SQR for Square root) for C02 a mean velocity at T = 2000K or T = 3000K (M _m = 44g / mol; R = 8.31441 JK ^" mol ^{" 1} ) of:

CR S3OOOK = 1304m / s

As a result of the collisions at these high temperatures, the rotational and vibrational states are filled up and finally dissociated.

The binding energy in C0 ₂ for the C-0 bond is 360 kJ / mol at room temperature. To break this bond, it is necessary to increase the temp. To 2000-3000 ° C, which corresponds to the supply of 63-100 kJ / mol of thermal energy.

Qi = (T ₂ -T ₁ ) ^* Cp = (2000K-298K) ^* 37.11 JK ^" 1mol ¹ = 63.161 kJ / mol

Q ₂ = ^ - ^^ = (3000 ^ 298 ^ ^* 37.11 JK ^'l ^"1 = 100.271 kJ / mol

It is therefore sufficient in the present case at the nozzle exit a speed of the exiting C0 ₂ gas molecules-the molecular beam-at least in the range of 1064-1302 m / s set. In the case of a nozzle diameter of 0.3mm this corresponds to one Flow (at 20 ° C) of about 5-71 / min. For this you have to work with a form of approx. 50-100bar. Thus, the described process is a transformation chain of pressure energy into kinetic energy (velocity) and via the reactive collision into chemical energy, bypassing the production of undirected momentum! The necessary energy input for the process is provided primarily via the compression (pressure energy) of the gases.

Since the provision of C0 ₂ at a pressure level well above 50bar sometimes associated with technical difficulties, since C0 _{2 has} a critical pressure of about 70 bar, it is possible the gas as a mixed gas, for example, with an addition of 20% -50% methane too store and then release at elevated pressure. As a result, the C0 ₂ can be accelerated faster, similar to the "seeded beams" described above, but the overall reaction is not a pure CQ ₂ dissociation but also a co-reaction of the methane via a complex mechanism.

When using such "seeded beams", the following relationship should be considered: If one accelerates a gas or a mixture of gases in a nozzle beyond a certain speed, the cooling effect is so great that the gas phase changes into the liquid phase Degrees of freedom therefore decrease drastically: Some gases (eg C0 ₂ ) cool down so strongly that they directly change into the solid phase (formation of so-called dry ice), in which case their molar heat capacity decreases even more.

It is also of interest that the molecules come much closer together in the solid state than in the gaseous (or liquid state). If such a crystal, which is just emerging, meets a foreign molecule, it will incorporate it into its crystal lattice. Depending on the size of the host molecules and the foreign molecule, so-called clathrates are formed in which the guest atoms are incorporated. In this context we also speak of "solid solutions".

If no guest molecule is incorporated, the physical behavior of the clathrate corresponds to that of the pure substance - that is, the melting point and sublimation point remain unchanged. However, the incorporation of guest molecules can alter the overall physical behavior of the clathrate. This is important insofar as a stabilization of the host lattice by guest molecules can increase the melting point and sublimation point.

It can therefore at very high speeds of molecular beams and special gases (eg C0 ₂ , H ₂ 0, CH ₄ ) to the formation of Clath rates instead of correct chemical reactions. This too can now be used for various applications. One of these is, for example, the simple storage of a gas A, which otherwise can only be stored under high pressure or liquefied, by adding a gas B, in the form of a solid clathrate.

Recommended literature:

L. Bergmann, The Ultrasound, VDI Verlag GmbH Berlin Nw7, 3rd Edition (1942)

R.D.Levine; R.B Bernstein, Molecular Reaction Dynamics, Teubner Studienbücher Chemie, (1991)

R.Brdicka, Foundations of Physical Chemistry, VEB Verlag der Wissenschaften Berlin, 3rd edition (1962)

LIST OF REFERENCE NUMBERS

1 reactor

2 First reactor end

3 Second reactor end

4 first gas (target gas)

5 second gas (reaction gas)

6 molecular beam

7 gas containers

8 nozzle

9 ultrasound siren

10 wall of the standing wave

11 node

12 supply line for second gas

13 reactor end in the form of a loudspeaker

Claims

claims:

1.) A method for carrying out a chemical reaction between a target gas and a molecular beam characterized in that a) in a reactor which is acoustically resonant or an acoustic resonator, a first gas (target gas) is presented,

d) in this reactor filled with the first gas then with the aid of an ultrasonic signal source by means of an ultrasonic signal with an ultrasonic frequency> 16 kHz a "standing wave" is generated in this first gas,

e) then in the reactor, a second gas (reaction gas) is introduced in the form of a molecular beam, wherein the molecular beam strikes at least one of the generated by ultrasound "walls" of the "standing waves" of the first gas.

2.) Process according to claim 1, characterized in that the second gas is introduced into the reactor in the molecular beam at a speed> 343 m / s, preferably the second gas is introduced into the reactor at a speed> 1000 m / s, in particular with a speed between 1050 m / s and 1350 m / s is registered in the reactor

and or

o that the ultrasonic frequency for generating the "standing wave" is between 16 kHz and 1 GHz, preferably between 16 kHz and 100 kHz, and / or

o that the first gas (target gas) is present in the reactor at a pressure of between 1 bar and 10 bar or between 1 bar and 20 bar before the formation of the "standing wave".

3.) Method according to one of claims 1 or 2 characterized in that

that the reactor has an elongated shape with two opposite reactor ends, wherein preferably at least one reactor end is closed or at least one reactor end is open,

and or that the reactor as an acoustic resonator at least partially consists of a tube, in particular preferably in the form of an acoustically resonant tube is executed;

and or

that the reactor is an acoustic resonator with two opposite

Reactor ends, which preferably consists at least partially of a tube and in which at least one reactor end is closed or at least one reactor end is open; in particular that the reactor is an acoustic

resonant tube with two opposite closed or open reactor ends, in which at least one reactor end is closed or at least one end of the reactor is open.

4.) Method according to one of claims 1 to 3, characterized in that the

Reactor has at least two opposite reactor ends,

wherein the ultrasonic signal source is arranged at a reactor end and the opposite reactor end is at least partially designed as a vibratable membrane, preferably as a vibratable metallic membrane, in particular made of Cu, Ag or Au;

and or

preferably characterized in that the reactor end at which the

Ultrasonic signal source is arranged, is designed in the form of a loudspeaker.

5.) Method according to one of claims 1 to 4, characterized in that both the first gas (the target gas) and the second gas (the reaction gas / the molecular beam) consists of a clean gas or a gas mixture; Preferably, the second gas (the reaction gas / the molecular beam) consists of a gas mixture, in particular the second gas (the reaction gas / the molecular beam) consists of a gas mixture of a gas of lower molecular weight and a gas of higher molecular weight.

6.) Method according to one of claims 1 to 5, characterized in that the first gas (target gas) and the second gas (the reaction gas / the molecular beam) have the same chemical composition.

7.) Method according to one of claims 1 to 6, characterized in that the first gas (target gas) and the second gas (the reaction gas / the molecular beam) have a different chemical composition.

8.) Method according to one of claims 1 to 7, characterized in that o the second gas is selected from CH ₄ or C0 ₂ or a

Gas mixture of CO ₂ and CH _{4) is} preferably selected from CH ₄ or CO ₂ or a gas mixture consisting of 80 vol.% - 50 vol.% C0 ₂ and 20 vol.% - 50 vol.% CH ₄ ,

and

o that the first gas (the target gas) is selected from CH ₄ or C0 ₂ or a gas mixture of C0 ₂ and CH, preferably selected from CH ₄ or C0 ₂ .

9.) Method according to one of claims 1 to 8, characterized in that the second gas (the reaction gas) in the form of the molecular beam

at a reactor end, preferably at a reactor end of a reactor designed as a pipe, perpendicular to at least one "wall of the standing wave" of the first gas (of the target gas), or

preferably at a reactor end of a reactor designed as a tube meets at least one vibration node of the generated in the first gas (the target gas) "standing wave", or

preferably the second gas in the form of the molecular beam parallel to

Pipe longitudinal axis of the tube designed as reactor is entered into the reactor.

10.) Method according to one of claims 1 to 9, characterized in that the

Ultrasonic signal by means of mechanical or electromechanical means

preferably by a Galton pipe, ultrasonic siren, lip whistle, Hartmann generator, vibrating rods, vibrating strings, magnetostrictive or piezoelectric, particularly preferably by an ultrasonic siren is generated.

1 1.) Method according to one of claims 1 to 10, characterized in that the

Reactor is poured into concrete,

and or

that the reactor is made of metal, plastic, ceramic or composites such as concrete or a combination of these materials.

12.) Method according to one of claims 1 to 1 1, characterized in that the second gas from a gas container in which the second gas is present with excess pressure is introduced via a nozzle in the reactor, wherein the nozzle preferably has a diameter of 0.01 mm to 1 mm, in particular has a diameter of 0.2 mm to 0.4 mm.

13.) reactor for carrying out a method according to one of claims 1 to 12, characterized in that the reactor is designed such that in a first gas filling it

(Target gas) with the help of an ultrasonic signal source by an ultrasonic signal with an ultrasonic frequency> 16 kHz kHz, a "standing wave" of this first gas can be generated

the reactor has an ultrasonic signal source and

there is an opening for introducing a second gas.

14.) reactor for carrying out a method according to one of claims 1 to 12, characterized in that

a. the reactor is a resonant container consisting at least partially of a tube in which a "standing wave" is or may be generated,

b. the reactor has an ultrasonic signal source and

c. an opening for introducing a second gas is present, wherein d. the ultrasonic signal source at one end of the reactor and a

vibratable membrane is present at the opposite end of the reactor and

e. the reactor end carrying the ultrasonic signal source in the form of a

Speaker is shaped.

15.) Reactor according to one of claims 13 or 14, characterized in that

o the reactor has elongated shape, preferably designed as a tube; and or the reactor has two opposite reactor ends, wherein preferably at least one reactor end is closed or at least one reactor end is open;

and or

the reactor is an acoustic resonator with two opposite ones

Reactor ends, which preferably consists at least partially of a tube and in which at least one reactor end is closed or at least one reactor end is open;

and or

the reactor is an acoustic resonator with two opposite ones

and or

the reactor is an acoustically resonant tube having two opposite closed or open reactor ends, in which at least one reactor end is closed or at least one reactor end is open; and or

the reactor has at least two opposite reactor ends, wherein the ultrasonic signal quench is arranged at a reactor end and the opposite reactor end is designed as a vibratable membrane, preferably as a vibratable metallic membrane, in particular made of Cu, Ag or Au;

and or

the reactor has at least two opposing reactor ends, the reactor end, on which the ultrasonic signal laughter is arranged, being in the form of a loudspeaker;

and or

that the ultrasonic signal by means of mechanical or electromechanical means preferably by a Galton pipe, ultrasonic siren, lip whistle, Hartmann generator, vibrating rods, vibrating strings,

magnetostrictive or piezoelectric, particularly preferably generated by an ultrasonic siren; and or

the reactor is poured into concrete;

and or

that the opening to the entry of the second gas is designed as a nozzle; and or

the second gas from a gas container in which the second gas is present with excess pressure, is introduced via a nozzle into the reactor, wherein the nozzle preferably has a diameter of 0.01 mm to 1 mm, in particular a diameter of 0.2 mm to 0.4 mm;

and or

the second gas in the form of the molecular beam is introduced into the reactor through the opening, preferably through a nozzle, parallel to the tube longitudinal axis of the reactor designed as a tube;

and or

the reactor is poured into concrete or several reactors together in

Poured concrete;

and or

the ultrasonic signal source at a reactor end and a vibratory

Membrane is present at the opposite end of the reactor;

and or

the reactor end carrying the ultrasonic signal source in the form of a

Speaker is shaped.