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PSRK VLE Prediction Cyclohexane And Carbon Dioxide
PSRK (short for Predictive Soave–Redlich–Kwong) is an estimation method for the calculation of phase equilibria of mixtures of chemical components. The original goal for the development of this method was to enable the estimation of properties of mixtures containing supercritical components. This class of substances cannot be predicted with established models, for example UNIFAC. Principle PSRK is a group-contribution equation of state. This is a class of prediction methods that combines equations of state (mostly cubic) with activity coefficient models based on Group-contribution method, group contributions, such as UNIFAC. The activity coefficient model is used to adapt the equation-of-state parameters for mixtures by a so-called mixing rule. The use of an equation of state introduces all thermodynamic relations defined for equations of state into the PRSK model. This allows the calculation of Density, densities, Enthalpy, enthalpies, Heat capacity, heat capacities, and othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UNIFAC
In statistical thermodynamics, the UNIFAC method ( UNIQUAC Functional-group Activity Coefficients)Aage Fredenslund, Russell L. Jones and John M. Prausnitz, "Group-Contribution Estimation of Activity Coefficients in Nonideal Liquid Mixtures", ''AIChE Journal'', vol. 21 (1975), p. 1086 is a semi-empirical system for the prediction of non-electrolyte activity in non-ideal mixtures. UNIFAC uses the functional groups present on the molecules that make up the liquid mixture to calculate activity coefficients. By using interactions for each of the functional groups present on the molecules, as well as some binary interaction coefficients, the activity of each of the solutions can be calculated. This information can be used to obtain information on liquid equilibria, which is useful in many thermodynamic calculations, such as chemical reactor design, and distillation calculations. The UNIFAC model was first published in 1975 by Fredenslund, Jones and John Prausnitz, a group of chemical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dortmund Data Bank
The Dortmund Data Bank (short DDB) is a factual data bank for thermodynamic and thermophysical data. Its main usage is the data supply for process simulation where experimental data are the basis for the design, analysis, synthesis, and optimization of chemical processes. The DDB is used for fitting parameters for thermodynamic models like NRTL or UNIQUAC and for many different equations describing pure component properties, e.g., the Antoine equation for vapor pressures. The DDB is also used for the development and revision of predictive methods like UNIFAC and PSRK. Contents Mixture properties * Phase equilibria data ( vapor–liquid, liquid–liquid, solid–liquid), data on azeotropy and zeotropy * Mixing enthalpies * Gas solubilities * Activity coefficients at infinite dilution * Heat capacities and excess heat capacities * Volumes, densities, and excess volumes (volume effect of mixing) * Salt solubilities * Octanol-water partition coefficients * Critical data T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eicosane
Icosane (alternative spelling eicosane) is an alkane with the chemical formula C20H42. It has 366,319 constitutional isomers. Icosane has little use in the petrochemical industry, as its high flash point makes it an inefficient fuel. ''n''-Icosane (the straight-chain structural isomer of icosane) is the shortest compound found in paraffin waxes used to form candles. Icosane's size, state or chemical inactivity does not exclude it from the traits its smaller alkane counterparts have. It is a colorless, non-polar molecule, nearly unreactive except when it burns. It is less dense than and insoluble in water. Its non-polar trait means it can only perform weak intermolecular bonding (hydrophobic/van der Waals forces). Icosane's phase transition at a moderate temperature makes it a candidate phase change material, or PCM which can be used to store thermal energy and control temperature. It can be detected in the body odor of persons suffering from Parkinson's disease. Naming IUPAC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a Volatility (chemistry), volatile, Combustibility and flammability, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. It is a psychoactive recreational drug, the active ingredient in alcoholic drinks. Ethanol is naturally produced by the fermentation process of Carbohydrate, sugars by yeasts or via Petrochemistry, petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the Chemical synthesis, synthesis of organic compounds, and as a Alcohol fuel, fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VTPR
VTPR (short for Volume-Translated Peng–Robinson) is an estimation method for the calculation of phase equilibria of mixtures of chemical components. The original goal for the development of this method was to enable the estimation of properties of mixtures which contain supercritical components. These class of substances couldn't be predicted with established models like UNIFAC. Principle VTPR is a group contribution equation of state. This is class of prediction methods combine equations of state (mostly cubic) with activity coefficient models based on group contributions like UNIFAC. The activity coefficient model is used to adapt the equation of state parameters for mixtures by a so-called mixing rule. The usage of an equation of state introduces all thermodynamic relations defined for equations of state into the VTPR model. This allows the calculation of densities, enthalpies, heat capacities, and more. Equations VTPR is based on a combination of the Peng–Robinson eq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bubble Point
In thermodynamics, the bubble point is the temperature (at a given pressure) where the first bubble of vapor is formed when heating a liquid consisting of two or more components. Given that vapor will probably have a different composition than the liquid, the bubble point (along with the dew point) at different compositions are useful data when designing distillation systems. For a single component the bubble point and the dew point are the same and are referred to as the boiling point. Calculating the bubble point At the bubble point, the following relationship holds: :\sum_^ y_i = \sum_^ K_i x_i = 1 where :K_i \equiv \frac. K is the ''distribution coefficient'' or ''K factor'', defined as the ratio of mole fraction in the vapor phase \big(y_\big) to the mole fraction in the liquid phase \big(x_\big) at equilibrium. When Raoult's law and Dalton's law hold for the mixture, the K factor is defined as the ratio of the vapor pressure to the total pressure of the system: :K_i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dew Point
The dew point is the temperature to which air must be cooled to become saturated with water vapor, assuming constant air pressure and water content. When cooled below the dew point, moisture capacity is reduced and airborne water vapor will condense to form liquid water known as dew. When this occurs via contact with a colder surface, dew will form on that surface. The dew point is affected by humidity. When there is more moisture in the air, the dew point is higher. When the temperature is below the freezing point of water, the dew point is called the frost point, as frost is formed via deposition rather than condensation. In liquids, the analog to the dew point is the cloud point. Humidity If all the other factors influencing humidity remain constant, at ground level the relative humidity rises as the temperature falls; this is because less vapor is needed to saturate the air. In normal conditions, the dew point temperature will not be greater than the air temperature, sinc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PSRK VLE Prediction Cyclohexane And Carbon Dioxide
PSRK (short for Predictive Soave–Redlich–Kwong) is an estimation method for the calculation of phase equilibria of mixtures of chemical components. The original goal for the development of this method was to enable the estimation of properties of mixtures containing supercritical components. This class of substances cannot be predicted with established models, for example UNIFAC. Principle PSRK is a group-contribution equation of state. This is a class of prediction methods that combines equations of state (mostly cubic) with activity coefficient models based on Group-contribution method, group contributions, such as UNIFAC. The activity coefficient model is used to adapt the equation-of-state parameters for mixtures by a so-called mixing rule. The use of an equation of state introduces all thermodynamic relations defined for equations of state into the PRSK model. This allows the calculation of Density, densities, Enthalpy, enthalpies, Heat capacity, heat capacities, and othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UNIFAC Consortium
The UNIFAC Consortium was founded at the Carl von Ossietzky University of Oldenburg at the chair of industrial chemistry of Prof. Gmehling to invite private companies to support the further development of the group-contribution methods UNIFAC and its successor modified UNIFAC (Dortmund). Both models are used for the prediction of thermodynamic properties, especially the estimation of phase equilibria. The UNIFAC consortium is a successful example of private sponsorship of a public university in Germany. History The consortium was founded in 1997 when the public financing of the further development of the models became unlikely. The models UNIFAC and mod. UNIFAC (Dortmund) have already been used widely in software for the simulation and synthesis of chemical processes. Many companies doing process development in the field of chemical engineering had announced their support for a new way to subsidize the further development. This is facilitated through the support of over 40 com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Pressure
In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''c and a ''critical pressure'' ''p''c, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures, and the ferromagnet–paramagnet transition (Curie temperature) in the absence of an external magnetic field. Liquid–vapor critical point Overview For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the vapor–liquid critical point. This was the first critical point to be discovered, and it is still the best known and most studied one. The figur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equation Of State
In physics, chemistry, and thermodynamics, an equation of state is a thermodynamic equation relating state variables, which describe the state of matter under a given set of physical conditions, such as pressure, volume, temperature, or internal energy. Most modern equations of state are formulated in the Helmholtz free energy. Equations of state are useful in describing the properties of pure substances and mixtures in liquids, gases, and solid states as well as the state of matter in the interior of stars. Overview At present, there is no single equation of state that accurately predicts the properties of all substances under all conditions. An example of an equation of state correlates densities of gases and liquids to temperatures and pressures, known as the ideal gas law, which is roughly accurate for weakly polar gases at low pressures and moderate temperatures. This equation becomes increasingly inaccurate at higher pressures and lower temperatures, and fails to predict ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Temperature
Critical or Critically may refer to: *Critical, or critical but stable, medical states **Critical, or intensive care medicine *Critical juncture, a discontinuous change studied in the social sciences. *Critical Software, a company specializing in mission and business critical information systems *Critical theory, a school of thought that critiques society and culture by applying knowledge from the social sciences and the humanities * Critically endangered, a risk status for wild species *Criticality (status), the condition of sustaining a nuclear chain reaction Art, entertainment, and media * ''Critical'' (novel), a medical thriller written by Robin Cook * ''Critical'' (TV series), a Sky 1 TV series * "Critical" (''Person of Interest''), an episode of the American television drama series ''Person of Interest'' *"Critical", a 1999 single by Zion I People *Cr1TiKaL (born 1994), an American YouTuber and Twitch streamer See also *Critic *Criticality (other) *Critical Conditi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
