MXGT05000006A

MXGT05000006A - Photoelectrochemical method of separating water into hydrogen and oxygen, using melanins or the analogues, precursors or derivatives thereof as the central electrolysing element

Info

Publication number: MXGT05000006A
Application number: MXGT/A/2005/000006A
Authority: MX
Inventors: Solis Herrera Arturo
Original assignee: Solis Herrera Arturo
Filing date: 2005-06-09
Publication date: 2007-04-20

Abstract

The present invention mainly consists in using melanins, melanin precursors, melanin derivatives, variants, melanin analogues or the precursors thereof, which may be natural or synthetic, pure or mixed with organic or inorganic compounds, metals, ions, or drugs, as a material for electrolysing water using as the only or main power source coherent or non-coherent, natural or synthetic light;melanins are further applied in systems for producing hydrogen from water, which are known as photoelectrochemical systems. Said systems incorporate a semiconducting material and a water electrolyser within a monolithic design useful for producing hydrogen directly from water by means of light of from about 200 nm to about 900 nm, the light acting as the only or main power source. Although simple in concept, the challenge was to find a material resistant to the process. At least two main criteria were to be fulfilled first, the system or compound intended to absorb light should generate enough powe r to start, lead and complete the photochemoelectrolytic reaction;and, second, the system should be affordable, stable and durable in an aqueous environment. Said requirements are reasonably and effectively fulfilled by the melanins, and the analogues, precursors or derivatives thereof, which represents a critical and substantial progress in solving the central problem concerning photoelectrochemical designs. The present process may be useful for generating hydrogen, oxygen and high-energy electrons, or synthesising water by binding hydrogen and oxygen atoms, thus generating electricity. Said process may be useful in further processes, thus having a multiplying effect, and being useful for reducing carbon dioxide, nitrates and sulphates amongst others.

Description

Photoelectrochemical method for the separation of water into hydrogen and oxygen, using melanin, its analogues, its precursors or its derivatives as electrolyzing central element.

DESCRIPTION OBJECT OF THE INVENTION The sphere of the technology to which this invention applies is in the area that comprises the processes or methods of obtaining alternative energy, particularly in the so-called photoelectrochemical processes, by means of which the generation of carbon atoms is obtained. hydrogen and oxygen, starting from the separation or partition of the water molecule with which we generate hydrogen atoms and also oxygen, having also generated high energy electrons, and very possibly with application as a new method for the reduction of molecules of carbon dioxide, nitrates, and sulfates. Because the reactions occur in both directions, our invention also has application for the generation of electricity, since by joining hydrogen and oxygen atoms, water molecules are formed and electrical current is generated.

BACKGROUND As far as the state of the art is concerned, the processes known up to now to separate the water molecule into hydrogen and oxygen atoms are, among others: a) the application of intense electric currents b) the heating of water to two mil ° C c) the separation of the water molecule by means of the solar / electrochemical method: (photoelectrochemical), which integrates a semiconductor material and a water electrolyzer in a monolithic design, to produce hydrogen directly from water, using light as only source of energy, Simple in concept, the challenge was to find a material that could support or sustain the entire process and to date the ideal or most suitable substrate had not been found, as some materials are very expensive, others are inefficient , the more they degrade rapidly, in addition to the fact that some require too demanding working conditions, so the cost-benefit relationship is not viable from the economic, ecological, political and other points of view. d) Another method of separating water is by concentrating solar energy (with mirrors, for example) in order to raise the water temperature to two thousand ° C. e) one more method is to use photosynthetic microbes such as green algae and cyanobacteria, which produce hydrogen from water as part of their metabolic activities using light energy as the main source. This photobiological technology is promising, but as oxygen is produced along with hydrogen, the technology must solve the limitation that is the sensitivity to oxygen of these enzymatic systems. In addition, the production of hydrogen from photosynthetic organisms is currently very low to be economically viable. f) Another method is the electrolysis of water, using electricity to separate the water molecule into its components (hydrogen and oxygen atoms), currently, two types of electrolysers are used for the commercial production of hydrogen: the alkaline and the proton exchange membrane, but these approaches currently can not compete, from the economic point of view, with hydrogen produced from natural gas. (Source: U: S: Department of Energy, Energy Efficiency and Renewable Energy, Hydrogen, Fuel Cells and Infrastructure Technologies Program, Hydrogen, Production & Delivery.) A natural material that can also split or separate the water molecule and that has been studied is chlorophyll, but because its affinity for light falls between 400 nm and around 700 nm, the rest of the luminous energy is lost, so it is estimated that 80% of the energy used is wasted and that its production is complex and expensive, for example it requires temperatures of -8o C. These were the reasons why I decided to use melanins as an electrolyzing element of water, because its affinity for the spectrum goes from 200 to 900 nm, and due to the physiological characteristics of the tissues in which melanin is normally found, it calls attention to parameters such as oxygen concentrations, so it was decided to contrast the hypothesis that when illuminating melanin or melanins, we would obtain the photolysis of the water molecule generating hydrogen and oxygen atoms, in addition to other products such as OH, hydrogen peroxide, superoxide anion, and high energy electrons, as well as sustain and catalyze the reverse reaction, that is, join hydrogen and oxygen atoms forming water molecules, also generating electricity.

DETAILED DESCRIPTION OF THE INVENTION The invention consists essentially of achieving, at room temperature and using light as an energy source, the partition of the water molecule, obtaining hydrogen and oxygen atoms, as well as high-energy electrons or joining hydrogen and oxygen atoms to obtain water and electric current, using as main or central electrolyzing material melanins, precursors of melanins, derivatives of melanins, variants and analogs of melanins (polyhydroxyindole, eumelanin, pheomelanin, allomelanin, neuromelanin, humic acid, fullerenes, graphite, polyindolquinones, acetylene black (acetylene-blac), pyrrole-black (pyrrole-black), indole-black (indole-black), benzene-black (benzene) black), thiophene black (thiophene-black), aniline-black (aniline-black), polyquinones in hydrated form, sepiomelanins, black dopa (dopa-black), black dopamine (dopamine-black), black adrenaline (adrenaline-black) , black catechol (catechol-black), 4aminocatecolnegra (4 amine catechol-black), (in simple linear chain, aliphatic or aromatic.) or its precursors such as phenols, aminophenols, o.difenoles, indole-polyphenols, cyclodopa, DHl and DHICA, quinones, semiquinones or hydroquinones, L-tyrosine, L-dopamine, morpholino ortho benzoquinone, dimorpholino-ortho-benzoquinone, morpholincatechol, orthobenzoquinone, porphyrin-black, pterin-black, ommochrome-black, nitrogen-free precursors, any of the above-mentioned with any particle size (from 1 angstrom to 3 or 4 cm), all the compounds mentioned above, electroactive, in suspension, in solution, in gel, that absorb ultrasound in the range of one MHz, natural or synthetic, of vegetable origin, animal or mineral; pure or mixed with organic or inorganic compounds, ions, metals (gadolinium, iron, nickel, copper, erbium, europium, praseodymium, dysprosium, holmium, chromium or manganese, lead selenide, etc.). Gadolinium is a very effective metal. The metal is incorporated into the melanins in ionic form or as a particle, in addition to drugs or drugs, energizing the photoelectrochemical design with light (natural or synthetic, coherent or not, monochromatic or polychromatic) with wavelength mainly between 200 and 900 nanometers , although other wavelengths are also effective, although to a variable degree, depending on the rest of the conditions (pH, temperature, pressure, etc). Magnetic fields from mild intensity to significant intensity can be applied to this type of design. The events in this design can happen to a greater or lesser degree under physical or chemical stimuli, internal or external. We propose the use of melanins (cited above) as the electrolyzing material of the water molecule, using light as the main or only energy, particularly between 200 and 900 nm wavelength, in hydrogen production systems known as methods photoelectrochemical These systems, as mentioned above, integrate a semiconductor material and a water electrolyzer into a monolithic design, to produce hydrogen atoms directly from water, using light as the main or only source of energy. Although simple in concept, the challenge was to find a material that supported the process in its entirety. At least two basic criteria had to be met: one was that the system or compound that absorbed the light should generate enough energy to initiate, conduct and fully support the electrolysis reaction, which should be low cost, stable and durable in an aqueous environment, requirements that melanins, precursors of melanins, derivatives of melanins, variants and analogues of melanins; they can fill in a reasonable and efficient way, which represents an advance in the solution of the central problem of photoelectrochemical designs. The shape of the container that contains it in the appropriate equipment, can be very varied, being able to be: cubic, cylindrical, spherical, polyhedral, rectangular, etcetera, being one of the main requirements that is transparent so as to allow the passage of light, and depending on the wavelength of the illumination to be used , the walls could be made of quartz, for example, so that the walls of the container do not absorb ultraviolet radiation, or in the case of selecting certain wavelengths, the material with which the container is made could be of a color that allow maximum transparency or absorption, where appropriate, of the wavelength of the electromagnetic spectrum of interest. It can be glass, or any polymer whose transmission characteristics of electromagnetic radiation are adjusted to the final needs of the photoelectrochemical design. The wavelengths that can be used to power the design range from 200 nanometers to 900 nanometers. Inside the cell, the main material, the indispensable solute for the photoelectrochemical design to work are soluble melanins, precursors of melanins, derivatives of melanins, variants and analogues of melanins dissolved mainly in water, since the base of the design is the remarkable ability of melanin to capture photons with wavelengths between 200 and 900 nm "which is probably done by the peripheral portions of the molecule, which is followed by the generation of high-energy electrons, from low energy electrons. These high energy electrons are directed towards the free radical centers of the compound, where they are captured by some element, for example some metal such as iron, copper, gadolinium, europium etc., from where they are transferred to a primary electron acceptor, uncertain nature to date, since the binding is complex and comprise ionic interactions, depending on the pH. This transfer of electrons releases energy, which is used to establish a proton gradient. The combination of melanin and water molecules forms what can be called a photosystem, which absorbs light energy by using it for at least two interrelated activities: removing electrons from water and generating a proton gradient. The components of melanin are in very close contact with each other, which facilitates the rapid transfer of energy. At 3 picoseconds of being illuminated the reaction centers of the melanins respond by transferring a photoexcited electron to the primary acceptor of electrons. This electron transfer generates a positively charged donor and a negatively charged acceptor. The importance of the formation of two oppositely charged species becomes apparent when we consider the reduction oxide capacities of these two species, since one of them is deficient in electrons and can accept electrons, which makes it an oxidizing agent. In contrast, the other compound has an extra electron that can easily be lost, making it a reducing agent. This event - the formation of an oxidizing agent and a reducing agent from light - takes less than one trillionth of a second and is the first essential step in photolysis. Because they are charged in the opposite way, these compounds exhibit an obvious attraction between them. The separation of charges is stabilized (probably) by the movement of the same, on opposite sides of the molecule; the negative compound being the one that first transfers its electron to a quinone (Q1), and possibly later the electron is transferred to a second type of quinone (Q2), which produces a semi-reduced form of the quinone molecule, which may be strongly linked to the reaction center of the melanin molecule. With each transfer, the electron moves closer and closer to the reaction center of the melanin molecule. The portion of the positively charged melanin is reduced, which prepares the reaction center for the absorption of another photon. The absorption of a second photon sends a second electron, along the pathway (negatively charged melanin towards the first and second quinone molecule -Q1 and Q2-), this second molecule absorbs two electrons, so it combines with two protons The protons used in this reaction could derive from the melanin molecule itself or from the water that surrounds it, causing a decrease in the concentration of hydrogen ions in the photosystem, which contributes to the formation of a proton gradient. Theoretically, the reduced quinone molecule dissociates from the melanin reaction center, being replaced by a new molecule of quinone. These reactions occur at room temperature, but modifying, for example the temperature, can favor reactions in one direction or another, depending on the control of the rest of the variables: pH, magnetic fields, concentrations, partial pressures of gases, electrodes, shape of the cells, etc.) and the main purpose of the process. The separation of the water molecule into hydrogen and oxygen atoms is a highly endergonic reaction due to the stable association of hydrogen and oxygen atoms. The separation of the water molecule (in hydrogen and oxygen atoms) in the laboratory requires the use of a strong electrical current or raise the temperature to almost 2000 ° C. The above (water electrolysis) is achieved by melanin at room temperature using only the energy it obtains from light, mainly between 200 and 900 nanometers of wavelength, either natural or artificial, coherent or not. It is estimated that the redox potential of the oxidized form of the quinone is approximately +1.1 V, which is strong enough to attract the tightly bound low energy electrons of the water molecule (redox potential of +0.82), which separates the molecule in hydrogen and oxygen atoms. The separation of the water molecule by photopigments is called photolysis. The formation of an oxygen molecule during photolysis is thought to require the simultaneous loss of four electrons from two water molecules according to the reaction: 2H20? 4H + + 02 + 4e "A reaction center can only generate a positive charge or its oxidizing equivalent at the same time.

This problem is hypothetically solved by the presence of 4 nitrogen atoms, in the reaction center of the melanin molecule, each of which transfers a single electron. This concentration of nitrogen, perhaps accumulates four positive charges when transferring four electrons (one at a time) to the nearest molecule of quinone +. The transfer of electrons from the nitrogens of the reaction centers to the + quinone is achieved by passage through a positively charged tyrosine residue. After each electron is transferred to quinone + regenerating quinone, the pigment is reoxidized (again to quinone +) after the absorption of another photon to the photosystem. Thus, the accumulation of four positive charges, (oxidizing equivalents) by the nitrogen atoms of the reaction center, is modified by the successive absorption of four photons by the melanin photosystem. Once the four charges have accumulated, the oxygen-releasing quinone complex is able to catalyze the removal of 4e ~ of 2H20, forming a 02 molecule, and regenerating the totally reduced accumulation of nitrogens from the reaction center. The protons produced in the photolysis are released in the medium, where they contribute to the proton gradient. The photosystem must be illuminated several times before a release of 02 occurs and therefore of hydrogen that can be measured, which indicates that the effect of individual photo reactions must accumulate before hydrogen and 02 are released. Quinones are considered carriers of mobile electrons. Do not forget that all electron transfers are exergonic and occur as the electrons are successively transferred to carriers with an increasing affinity for electrons. (more positive redox potentials) The need for the presence of mobile electron carriers is evident. The electrons generated by the photolysis can pass to several inorganic acceptors, which are therefore reduced. These electron pathways can lead (depending on the composition of the mixture used) to the eventual reduction of nitrate molecules (NO3" ) in ammonia molecules (NH3) or sulfates in sulfhydryls (SH), reactions that convert the inorganic waste in compounds necessary for life. Thus, the energy of sunlight can be used not only to reduce the most oxidized form of carbon atoms (C02) but also to reduce the most oxidized forms of nitrogen and sulfur.

The production of a 02 molecule requires the removal of four electrons from two water molecules, the removal of four electrons from water requires the absorption of four photons, one for each electron.

The design of the cell is an important parameter for the optimization in obtaining the product of the reaction in which we have particular interest, since the addition of electrodes, the nature of them, the use of magnetic fields, the addition of various compounds (organic and inorganic, ions, metals, drugs or drugs) to the photosystem that is initially only melanin and water, plus the addition of electrolytes, plus the addition of drugs, as well as temperature management, pressure control partial of the gases, the management of the electric current generated, the application of magnetic fields, the pH level, the material used in the manufacture of the cells and the shape and arrangement of their internal divisions, etc. in addition to other variables that are can be controlled so that the final design is to recover electrons, protons or oxygen, as well as resulting compounds according to the formulation of the medium in which melanin dissolves. That is, melanins, precursors of melanins, melanin derivatives, melanin variants and analogs (their analogs, their synthetic or natural precursors, pure or combined with organic and inorganic compounds, metals) allow a remarkable flexibility of the design of according to the purposes pursued. The optimization of the photoelectrochemical design is a matter of the purpose that you want to give, for example for a greater generation of protons and oxygen, or generation of electricity; the greatest possible area of exposure of the liquid compound to light, by means of an extended container, in addition to other procedures such as the addition of electron-carrying compounds, the doping of the melanins, or positive microlenses to concentrate the light, and so on. The design of the container has virtually no limits, it can be spherical, cubic, rhombic, polyhedron, concave plane, convex plane, biconvex, biconcave, with microlens on one side (the side exposed to light, to concentrate it) and plane on the other side , cylindrical, circular cylindrical, hollow cylinder, circular cone (straight), truncated cone, rectangular prism (straight), oblique prism, rectangular pyramid (straight), truncated pyramid, truncated spherical segment, spherical segment, spherical sector, spherical with cylindrical perforation , sphere with conical perforations, bull (ring of circular section), cylinder with inclined cut, wedge cylindrical, barrel, prismatóide, as well as combinations between these, and so on.

Since the liquid is accommodated in any way, it is only required to be transparent to allow the passage of the maximum possible light, and depending on the type of melanin used (doped or not, for example) will be the convenience of selecting some wavelength specific to illuminate soluble melanin, but so far one of the great virtues of soluble synthetic melanin is that it absorbs the vast majority of wavelengths. Between 200 and 900 nanometers of wavelength is where it shows its greatest absorption. The control of the partial pressures of the gases inside the cell is a variable that is important, and depending on the shape of the cell and the use that is given, and these pressures can range from 0.1 mm Hg to 3 or 4 atmospheres of pressure; Another variable that must be taken care of is the concentration of the different dissolved substances in the liquid, where the critical concentration is mainly that of the melanins, which can fluctuate from 0.1% to 100%; another variable that can be modified is the ratio between the different components of the formula (depending on the use) since we can add potassium in concentrations of 0.1 to 10%, sodium in concentrations from 0.1 to 10%, chlorine in concentrations from 0.1 to 10 %; calcium in concentrations from 0.1 to 10%, iron in concentrations from 0.1 to 8%, copper in concentrations from 0.1 to 8%, arsenic in concentrations from 0.1 to 8 or 9%, gold in concentrations ranging from 0.1 to 8 or 9 %, silver in concentrations similar to those of gold, nickel in concentrations from 0.1 to 8%, gadolinium, europium, erbium, etc. The final volume can range from 1 microliter to 10 or 20 liters depending on the size of the container and the space available for it, as far as the temperature can fluctuate between 2 and 45 ° C, the frequency of change of the solution can be from every 15 minutes to several months or 2 or 3 years; the formation of compartments within the cell, can be used inside the cell forms ranging from small spheres (microspheres, which can comprise several tens of them) to spheres whose size can be included three or four times within the complete design, and within the shapes of the inside of the cell we can include cubic, rhombic, polyhedral, concave plane, convex, biconvex, biconcave, with biconvex micro-cells on one side (the side exposed to light, to concentrate it) and the other plane side, cylindrical; circular cylindrical, hollow cylinder, circular cone (straight), truncated cone, rectangular prism (straight), oblique prism, rectangular pyramid (straight), truncated pyramid, truncated spherical segment, spherical segment, spherical sector, spherical with cylindrical perforation, sphere with Conical perforations, torus (ring of circular section), cylinder with inclined cut, cylindrical wedge, barrel, prismatoid, as well as combinations among these, the power of microlenses can range from 0.1 to 100 diopters, the redox properties of the materials used in the formation of the compartments (iron, silver, copper, nickel, gold, platinum, gallium arsenide, silicon, gadolinium, europium, erbium, praseodymium, dysprosium, holmium, chromium, manganese, lead selenide, alloys thereof and so on) , the use or not of cathodes and anodes, the material thereof (for example platinum, iron, silver, gold, steel, aluminum, nickel, arsenides, gadolinium, europium, erbium, pras eodimium, dysprosium, holmium, chromium, manganese; gallium) according to the optimal characteristics to recover electrons; another variable is the initial pH of the solution that can range from 2 or 3 to 8 or 9 pH units, being the most used around 7, are variables that can be managed in order to control the process of photoelectrolysis and adapt it to the needs of the project for which the photoelectrochemical design is used. Although the heart of any effective photoelectrochemical design are melanins. That is, melanins, precursors of melanins, melanin derivatives, variants and analogues of melanins, soluble in water, where they catalyze the photolysis process, without undergoing significant changes, except in the presence of elements such as manganese, iron, copper, lead and others; The resulting products together with the partial reduction of the oxygen atom (superoxide anion, hydroxyl radical, hydrogen peroxide, quinones and orthoquinones) can quickly or slowly deteriorate the efficiency of the melanins, but in the case of using pure melanin, at a concentration of 10% for example, the duration of the compound is long enough to be economically convenient (years), and the synthesis of melanin is a very efficient process, so from the economic and ecological point of view it is very viable, since it is biodegradable. So the cell only requires periodic provision of distilled water, and periodic replacement of soluble melanin, or if necessary renewal of substances that are added to the design to optimize or potentiate some of the processes that occur as a result of exposing the photoelectrochemical design to light. The ecological advantage that the final products of the reaction are water molecules, atoms and / or molecules of oxygen, hydrogen, high-energy electrons and electric current is easily palpable. There is little generation of greenhouse C02 molecules. The transfer of electrons releases energy, which is used to establish a proton gradient. The movement of protons during the transport of electrons can be compensated by the movement of other ions, so by using a membrane and a solvent with suitable solutes, we can build a membrane potential from the capture of photons by means of melanin. . The electrolyzing properties of melanin (among many others) can explain the peak generated by light observed in the electroretinogram, since when the melanin is illuminated the intracellular pH drops, which activates the pH-sensitive chlorine channels in the basolateral cell membrane. (The peak of light is an increase in the potential that follows the phase FOT (fast oscillation through) and forms the slowest and longest component of the direct current electroretinogram (Kris 1958, Kolder 1959, Kikadawa 1968, Steinberg 1982.) melanins, precursors of melanins, melanin derivatives, melanin variants and analogs, oxidize the water molecule to O, 02 and H2, consuming energy that it obtains from light (photons), and reduces oxygen atoms with atoms of hydrogen to H20 molecules, releasing energy (electricity), so that the design of the cell can be adapted to what is required to produce H2 and 02 atoms with light, but the generation of these elements can be increased by doping the melanins (melanin, its precursors, its variants, its derivatives, or its synthetic or natural analogues) with metals, or by adding organic and inorganic molecules, also modifying the electronic concentrations olitos, adding drugs, or controlling the characteristics of the light on the liquid that contains water and melanins (melanin, its derivatives, its precursors, its variants, its derivatives, its synthetic or natural analogues), for example with a basic design of microlenses to condense, or by selecting a certain wavelength, using coherent or scattered light, monochromatic, polychromatic, continuous, discontinuous, natural, artificial; etc. The photoelectrochemical reactions happen in both directions, ie the water molecule is separated but it is also formed, so that electrical current can be recovered from the design and can also be optimized by doping the melanins with different substances (drugs, metals, electrolytes , organic and inorganic molecules and others) or by light concentration through lenses, among others. The box containing the liquid can have various shapes that adapt to different needs, on the roofs of houses, roofs of cars, plants, buildings, industrial processes, etc., but the central component of the design is still melanin (melanins, its precursors, its derivatives, its variants, its analogues, soluble in water, which are the ones that induce and carry out the photolysis of the water molecule, in the presence of light .. Melanins, precursors of melanins, derivatives of melanins , variants and analogues of melanins; they remove electrons from water and generate a proton gradient. Light-dependent reactions can also provide energy to reduce C02 to CH20, nitrates to ammonia and sulfates to sulfhydryls. A compound that has been reported in the literature and that has been proven to induce and effect these processes is chlorophyll, but because it absorbs light mainly in the extreme regions of the visible spectrum, it is estimated that 80% of the energy is wasted irradiated, in contrast to our proposal to use melanin, since it practically absorbs soft and hard ultraviolet electromagnetic radiation, the entire visible spectrum and the near and far infrared lengths. (Spicer &Goldberg 1996). It is not remote that it can absorb other types of energy or wavelengths.

EXAMPLES We have carried out small-scale experiments, once we inferred these interesting properties of the melanins according to the structure-activity relationship, we placed synthetic melanin soluble in water, forming a 1% solution, in 5 bottles of high density transparent polyethylene, with a capacity of 20 mL, at room temperature, we measure the pH before and after illuminating them for 30 minutes with visible light from a natural source (sun) not concentrated; and when measuring the pH, we obtained on average a decrease of two tenths of pH units (from 7.3 to 7.1), we consider it significant because the melanins have a buffering property per se, so the change must be greater, but is masked by the intrinsic buffer property of melanin, so we only detect a part of this pH change, a change in pH whose magnitude is in accordance with a biological system, because if it were greater, it would probably destroy or seriously injure to the cell, but a change of this magnitude is sufficient to induce the biological changes in which this extraordinary compound intervenes. In order to measure the biological importance of a decrease of 0.2 pH units, we will mention that this decrease increases the calcium concentration by more than 10% in the case of blood. In addition, the pH of the whole blood goes from 7.38 to 7.44, the arterial blood goes from 7.36 to 7.41 and that of the venous blood ranges from 7.37 to 7.45, that is, the variations are within a very narrow range, so the difference of 2 decimas of pH unit really is significant in a biological system. On the other hand, the melanocyte is the cell with the highest affinity for Calcium in the organism, because it is a thousand times more similar to Calcium than bone, because although the latter has a greater amount, it only deposits in a mineral form. It should be noted, that said change of 0.2 pH units; as well as its reversion once the bottles were placed in a dark place, it was foreseen by our theoretical framework, that is, when we did the experiment we already knew what was going to be, in other words, we did not do many experiments, we just did it twice, and both times it turned out as we expected. The melanin solutions used in the experiments had 3 years of preparation, they are not doped; but as the theoretical framework indicates, it is a compound that is very durable, does not require preservatives, does not require refrigeration, is not contaminated with microorganisms despite the preparation time, these solutions are only kept in a cool and dry place; so we were relatively sure that the reaction was going to happen, although its magnitude could not be foreseen because the buffer capacity of melanin is not known or it is not possible to dimension it exactly because the melanin formula is not known In its whole. This experiment also showed that melanin does not require preservatives and that its electrolyzing properties preserve them despite time (3 years of synthesized). We are currently working on implementing the protocols that will lead us to try to answer some of the many questions that are generated from these experiments, but due to the extraordinary possibilities of industrial, medicinal, energy and laboratory application of this electrolyzing characteristic of Melanin, is that we decided to protect its use in the photoelectrochemical processes of power generation immediately. Another example on which our patent is based is the fact that blood enters the eye (arterial) through the choroidal vessels, which are surrounded by melanocytes; it has an oxygen saturation of 97%, and at its output, in the vorticoses, the oxygen saturation is 94%, being the C02 of 40%. Note that a decrease of only 3% in oxygen saturation is very intriguing. This unusual feature is not explainable by the high velocity of ocular blood flow, which in itself is extraordinary since it ranges between 10 and 20 mL / min / g which is 10 to 20 times more than that of the brain which is 0.5 mlJmin / g, besides if the flow rate was the explanation , then the oxygen saturation of the retina vessels would be similar (97% in the artery and 94% in the central vein of the retina with a CO 2 of 40%) but this is not the case, since in the retina vessels the figures are as in the rest of the organism, that is 97% oxygen at the entrance, 60% at the exit (in the vein), and a C02 of 40%. This intriguing difference, which is not explained in the literature until now, is resolved if we take into account the electrolyzing property of melanin. Which is not mentioned in any literature, we are the first to infer and report the fact. Another biological event that supports our patent is the case that when illuminating the pigment epithelial cells of the retina, normally; there is a decrease in intracellular pH values, a change that in the literature consulted to date is not explained, but if we take into account the electrolyzing property of melanin whose use we are patenting, that is, in the presence of light, melanin part of the water molecule and generates hydrogen and oxygen atoms, then the two events mentioned above are explained, the mysterious 94% oxygen saturation of venous choroidal blood (the choroid is very pigmented normally) and the decrease in cytoplasmic pH of the cells of the pigmented epithelium of the retina when illuminated. For something nature put so much pigment in the eye, 40% more than in the skin. Another example that supports our patent is the peak generated by observable light in the electroretinogram or recording of the electrical activity of the retina, pigmented epithelium and choroid; since when illuminating the melanin and generating hydrogen atoms, the intracellular pH lowers, which activates the chlorine channels sensitive to the pH in the basolateral cell membrane. (The peak light is an increase in the potential that follows the phase FOT (fast oscillation through) and forms the slowest and longest component of the direct current electroretinogram, an event whose molecular substrate has not been elucidated until now, but the properties electrolysers of melanin explain it quite well.

Claims

CLAIMS Having sufficiently described my invention, I consider as a novelty and therefore claim as my exclusive property, what is contained in the following clauses:

1. The photoelectrochemical process for the separation or union of water molecules comprising the use of melanins, precursors of melanins, derivatives of melanins, variants, melanin analogues; natural or synthetic, pure or mixed (with organic or inorganic substances, metals, ions, drugs) and that allows the separation of water into hydrogen and oxygen and / or its incomplete reduction derivatives and that use light of any type as the main energy source source (natural or synthetic, coherent or not) with wavelength mainly between 200 and 900 nanometers, although other wavelengths and other forms of energy can also be useful (sound, mechanical agitation, magnetic fields, etc.) depending on the physical-chemical configuration of the system, which will also result in the generation of high-energy electrons or the opposite reaction, that is, the union of hydrogen and oxygen forming water and generating electricity. Incomplete products of oxygen reduction such as superoxide anion, hydrogen peroxide and hydroxides can also be generated. All the above occurs at room temperature, and is susceptible to change according to the parameters and variables surrounding a design of this nature, such as the very nature of the melanin used in the design, the addition of some metals, as well as compounds organic, inorganic, drugs, pressure, temperature, pH; gases, shape of the continent, rheological characteristics of the content; the way to energize the process as it is by natural light, artificial light, visible, invisible, concentrated, coherent.

2. The use of melanins as a medium or electrolyzing material, precursors of melanins, derivatives of melanins, variants, melanin analogues; natural or synthetic, pure or mixed (with organic or inorganic compounds, metals, ions, drugs) for the photoelectrochemical process, as claimed in 1, where said substances may be: polyhydroxyindole, eumelanin, pheomelanin, allomelanin, neuromelanin, humic acid, fullerenes, graphite, polyindoquinones, acetylene black (acetylene-black), pyrrole -black (pyrrole-black), indole-black (indole-black), benzene-black (benzene-black), thiophene black (thiophene-black), aniline-black (aniline-black), polyquinones in hydrated form, sepiomelanins, black dopa (dopa-black), black dopamine (dopamine-black), black adrenaline (adrenaline-black), black catechol (catechol-black), 4aminocatecolnegra (4 amine catechol-black); (in simple linear chain, aliphatic or aromatic.) or its precursors such as phenols, aminophenols, odifenols, indole-polyphenols, cyclodopa, DH1 and DHICA, quinones, semiquinones or hydroquinones, tyrosine (L or D), dopamine (L or D) , morpholino ortho benzoquinone, dimorphoiino-ortho-benzoquinone, morpholincatechol, orthobenzoquinone, porphyrin-black, pterin-black, ommochrome-black, nitrogen-free precursors, any of those cited with any particle size (from 1 angstrom to 3 or 4 cm ), all the compounds mentioned above, electroactive, in suspension or in solution, which absorb ultrasound in the range of one MHz, natural or synthetic, of vegetable, animal or mineral origin; , pure or mixed with organic or inorganic compounds, ions, drugs or drugs) as central, principal or essential materials or, accessories. In the process should be considered the concentrations mainly of melanin, which can fluctuate from 0.1% to 100% or more, depending on the physicochemical and rheological characteristics of the design.

3. The use of melanins as a medium or electrolyzing material, precursors of melanins, derivatives of melanins, variants, melanin analogues; natural or synthetic, pure or mixed (with organic or inorganic compounds, metals, ions, drugs) for a process that includes the reduction of carbon dioxide, sulfates and nitrates.

4. The use of melanins as a medium or electrolyzing material, precursors of melanins, derivatives of melanins, variants, melanin analogues; natural or synthetic, pure or mixed (with organic or inorganic compounds, metals, ions, drugs) for the photoelectrochemical process of water, as claimed in 1, or by exploiting the property of melanins to generate hydrogen peroxide, anion superoxide, hydroxides and monoatomic or molecular oxygen or high-energy electrons, from water, using as main source of energy electromagnetic radiation of wavelength mainly between 200 and 900 nm, although other wavelengths and other forms of energy, such as : mechanical agitated sound, magnetic fields, among others.

5. The use of melanins, precursors of melanins, derivatives of melanins, variants, analogs of melanins; natural or synthetic, pure or mixed (with organic or inorganic compounds, metals, ions, drugs), as claimed in 4 that allows to separate water into hydrogen and oxygen and or its incomplete reduction derivatives and that use light from any source (natural or synthetic, coherent or not) with wavelength mainly between 200 and 900 nanometers.

6. The use of melanins, precursors of melanins, derivatives of melanins, variants, analogs of melanins; natural or synthetic, pure or mixed (with organic or inorganic compounds, metals, ions, drugs), as claimed in 4, in designs whose purpose is to produce energy, either through the production of electrical current, or through generation of hydrogen directly from the photoelectrochemical separation of water, or by taking advantage of the property of the melanins to generate hydrogen peroxide, superoxide anion, hydroxides and monoatomic or molecular oxygen.

7. The apparatus for carrying out the photoelectrochemical process of energy production, by means of the use of melanins, precursors of the melanins, derivatives of the melanins, variants, analogs of the melanins; natural or synthetic, pure or mixed (with organic or inorganic compounds, metals, ions, drugs) as a medium or electrolyzing material, comprising the application of magnetic fields from mild intensity to a significant intensity, whose events may occur to a greater or lesser degree under physical or chemical stimuli, internal or external; for the exposure of said substances they must be contained in a container, made of a transparent material to allow the passage of as much light as possible. In addition, said apparatus carries out the control of the partial pressures which can vary from 0.1 mm Hg to 3 or 4 atmospheres of pressure

8. The apparatus for carrying out the photoelectrochemical process of energy production, as claimed in 7, whose container allows the exposure of said substances in the largest possible area by means of an extended container or having the following forms: spherical, cubic, rhombic, polyhedral, concave plane, convex plane, biconvex, biconcave, with micro-lights on one side (the side exposed to light, to concentrate it) and plane on the other side, cylindrical, circular cylindrical, hollow cylinder, circular cone (straight), truncated cone , rectangular prism (straight), oblique prism, rectangular pyramid (straight), truncated pyramid, truncated spherical segment, spherical segment, spherical sector, spherical with cylindrical perforation, sphere with conical perforations, torus (circular section ring), cylinder with cut inclined, cylindrical wedge, barrel, prismatoid.