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Electrodialysis
Electrodialysis (ED) is used to transport salt ions from one solution through ion-exchange membranes to another solution under the influence of an applied electric potential difference. This is done in a configuration called an electrodialysis cell. The cell consists of a feed (dilute) compartment and a concentrate ( brine) compartment formed by an anion exchange membrane and a cation exchange membrane placed between two electrodes. In almost all practical electrodialysis processes, multiple electrodialysis cells are arranged into a configuration called an electrodialysis stack, with alternating anion and cation-exchange membranes forming the multiple electrodialysis cells. Electrodialysis processes are different from distillation techniques and other membrane based processes (such as reverse osmosis (RO)) in that dissolved species are moved away from the feed stream, whereas other processes move away the water from the remaining substances. Because the quantity of dissolve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ion-exchange Membrane
An ion-exchange membrane is a semi-permeable membrane that transports certain dissolved ions, while blocking other ions or neutral molecules. Ion-exchange membranes are therefore electrically conductive. They are often used in desalination and chemical recovery applications, moving ions from one solution to another with little passage of water. Important examples of ion-exchange membranes include the proton-exchange membranes, that transport cations, and the anion exchange membranes used in certain alkaline fuel cells to transport anions. Structure and composition An ion-exchange membrane is generally made of organic or inorganic polymer with charged (ionic) side groups, such as ion-exchange resins. Anion-exchange membranes contain fixed cationic groups with predominantly mobile anions; because anions are the majority species, most of the conductivity is due to anion transport. The reverse holds for cation-exchange membranes. The so-called heterogeneous ion-excha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brine
Brine (or briny water) is a high-concentration solution of salt (typically sodium chloride or calcium chloride) in water. In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature). Brine forms naturally due to evaporation of ground saline water but it is also generated in the mining of sodium chloride. Brine is used for food processing and cooking (pickling and brining), for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, so it requires wastewater treatment for proper disposal or further utilization (fresh water recovery). In nature Brines are produced in multiple ways in nature. Modification of seawater via evaporation results in the concentration of salts in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Osmosis
Reverse osmosis (RO) is a water purification process that uses a partially permeable membrane, semi-permeable membrane to separate water molecules from other substances. RO applies pressure to overcome osmotic pressure that favors even distributions. RO can remove dissolved or suspended chemical species as well as biological substances (principally bacteria), and is used in industrial processes and the production of potable water. RO retains the solute on the pressurized side of the membrane and the purified solvent passes to the other side. The relative sizes of the various molecules determines what passes through. "Selective" membranes reject large molecules, while accepting smaller molecules (such as solvent molecules, e.g., water). Reverse osmosis is most commonly known for its use in drinking water purification from seawater, removing the salt and other effluent materials from the water molecules. As of 2013 the world's largest RO desalination plant was in Nahal Sorek, So ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Splitting
Water splitting is the chemical reaction in which water is broken down into oxygen and hydrogen: Efficient and economical water splitting would be a technological breakthrough that could underpin a hydrogen economy. A version of water splitting occurs in photosynthesis, but hydrogen is not produced. The reverse of water splitting is the basis of the hydrogen fuel cell. Water splitting using solar radiation has not been commercialized. Electrolysis Electrolysis of water is the decomposition of water (H2O) into oxygen (O2) and hydrogen (H2): Production of hydrogen from water is energy intensive. Usually, the electricity consumed is more valuable than the hydrogen produced, so this method has not been widely used. In contrast with low-temperature electrolysis, high-temperature electrolysis (HTE) of water converts more of the initial heat energy into chemical energy (hydrogen), potentially doubling efficiency to about 50%. Because some of the energy in HTE is supplied in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen
Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter. Under standard conditions, hydrogen is a gas of diatomic molecules with the chemical formula, formula , called dihydrogen, or sometimes hydrogen gas, molecular hydrogen, or simply hydrogen. Dihydrogen is colorless, odorless, non-toxic, and highly combustible. Stars, including the Sun, mainly consist of hydrogen in a plasma state, while on Earth, hydrogen is found as the gas (dihydrogen) and in molecular forms, such as in water and organic compounds. The most common isotope of hydrogen (H) consists of one proton, one electron, and no neutrons. Hydrogen gas was first produced artificially in the 17th century by the reaction of acids with metals. Henry Cavendish, in 1766–1781, identified hydrogen gas as a distinct substance and discovere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorine
Chlorine is a chemical element; it has Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidizing agent, oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Electronegativity#Pauling electronegativity, Pauling scale, behind only oxygen and fluorine. Chlorine played an important role in the experiments conducted by medieval Alchemy, alchemists, which commonly involved the heating of chloride Salt (chemistry), salts like ammonium chloride (sal ammoniac) and sodium chloride (common salt), producing various chemical substances containing chlorine such as hydrogen chloride, mercury(II) chloride (corrosive sublimate), and . However, the nature of fre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy
Energy () is the physical quantity, quantitative physical property, property that is transferred to a physical body, body or to a physical system, recognizable in the performance of Work (thermodynamics), work and in the form of heat and light. Energy is a Conservation law, conserved quantity—the law of conservation of energy states that energy can be Energy transformation, converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J). Forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a Classical field theory, field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, the internal energy contained within a thermodynamic system, and rest energy associated with an object's rest mass. These are not mutual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diffusion
Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical potential. It is possible to diffuse "uphill" from a region of lower concentration to a region of higher concentration, as in spinodal decomposition. Diffusion is a stochastic process due to the inherent randomness of the diffusing entity and can be used to model many real-life stochastic scenarios. Therefore, diffusion and the corresponding mathematical models are used in several fields beyond physics, such as statistics, probability theory, information theory, neural networks, finance, and marketing. The concept of diffusion is widely used in many fields, including physics (Molecular diffusion, particle diffusion), chemistry, biology, sociology, economics, statistics, data science, and finance (diffusion of people, ideas, data and price v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shunt (electrical)
A shunt is a device that is designed to provide a low-resistance path for an electrical current in a Electrical network, circuit. It is typically used to divert current away from a system or Electronic component, component in order to prevent overcurrent. Electrical shunts are commonly used in a variety of applications including power distribution systems, electrical measurement systems, automotive and marine applications. Defective device bypass One example is in miniature Christmas lights (holiday decoration), Christmas lights which are series circuit, wired in series. When the Electrical filament, filament burns out in one of the incandescent light bulbs, the full line voltage appears across the burnt out bulb. A shunt resistor, which has been connected parallel circuits, in parallel across the filament before it burnt out, will then short out to bypass the burnt filament and allow the rest of the string to light. If too many lights burn out however, a shunt will also burn o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Sulfate
Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 million tonnes, the decahydrate is a major commodity chemical product. It is mainly used as a filler in the manufacture of powdered home laundry detergents and in the Kraft process of paper pulping for making highly alkaline sulfides. Forms *Anhydrous sodium sulfate, known as the rare mineral thénardite, used as a drying agent in organic synthesis. *Heptahydrate sodium sulfate, a very rare form. *Decahydrate sodium sulfate, known as the mineral mirabilite, widely used by chemical industry. It is also known as Glauber's salt. History The decahydrate of sodium sulfate is known as Glauber's salt after the Netherlands, Dutch–Germany, German chemist and apothecary Johann Rudolf Glauber (1604–1670), who discovered it in Austrian spring water i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
