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Known

In liquid-liquid equilibria, the total composition and temperature are known the pressure is usually not important. [Pg.3]

Equation (10a) is somewhat inconvenient first, because we prefer to use pressure rather than volume as our independent variable, and second, because little is known about third virial coefficients It is therefore more practical to substitute... [Pg.28]

For systems of type II, if the mutual binary solubility (LLE) data are known for the two partially miscible pairs, and if reasonable vapor-liquid equilibrium (VLE) data are known for the miscible pair, it is relatively simple to predict the ternary equilibria. For systems of type I, which has a plait point, reliable calculations are much more difficult. However, sometimes useful quantitative predictions can be obtained for type I systems with binary data alone provided that... [Pg.63]

Many well-known models can predict ternary LLE for type-II systems, using parameters estimated from binary data alone. Unfortunately, similar predictions for type-I LLE systems are not nearly as good. In most cases, representation of type-I systems requires that some ternary information be used in determining optimum binary parameter. [Pg.79]

One of the limitations of most phase-equilibrium data is that variances of experimental measurements are seldom known. [Pg.106]

The maximum-likelihood method is not limited to phase equilibrium data. It is applicable to any type of data for which a model can be postulated and for which there are known random measurement errors in the variables. P-V-T data, enthalpy data, solid-liquid adsorption data, etc., can all be reduced by this method. The advantages indicated here for vapor-liquid equilibrium data apply also to other data. [Pg.108]

If the equilibrium ratios were known or specified. Equation (7-8) could be substituted in Equation (7-6) or Equation (7-9) in (7-7) to give implicit relations for a ... [Pg.113]

A estimate of vapor to feed mole ratio, if known ... [Pg.320]

X(I) vector of estimated equilibrium liquid composition (mole fraction) if known (I = 1, N) otherwise can be any vector not summing to 1. [Pg.320]

T temperature (K) of isothermal flash for adiabatic flash, estimate of flash temperature if known, otherwise set to 0 to activate default initial estimate. [Pg.320]

PARIN first loads all pure component data by reading two records per component. The total number of components, M, in the library or data deck must be known beforehand. Next the associ-ation/solvation parameters are input for M components. Finally all the established UNIQUAC binary interaction parameters (or noncondensable-condensable interaction parameters) are read. [Pg.341]

U(J,I) FORMAT(2I5, 2F10.2) giving all known interaction parameters. [Pg.345]

Most processes are catalyzed where catalysts for the reaction are known. The strategy will be to choose the catalyst, if one is to be used, and the ideal characteristics and operating conditions needed for the reaction system. Decisions must be made in terms of reactor... [Pg.15]

This termination step stops the subsequent growth of the polymer chain. The period during which the chain length grows, i.e., before termination, is known as the active life of the polymer. Other termination steps are possible. [Pg.22]

Most processes are catalyzed where catalysts for the reaction are known. The choice of catalyst is crucially important. Catalysts increase the rate of reaction but are unchanged in quantity and chemical composition at the end of the reaction. If the catalyst is used to accelerate a reversible reaction, it does not by itself alter the position of the equilibrium. When systems of multiple reactions are involved, the catalyst may have different effects on the rates of the different reactions. This allows catalysts to be developed which increase the rate of the desired reactions relative to the undesired reactions. Hence the choice of catalyst can have a major influence on selectivity. [Pg.46]

In the first class, azeotropic distillation, the extraneous mass-separating agent is relatively volatile and is known as an entrainer. This entrainer forms either a low-boiling binary azeotrope with one of the keys or, more often, a ternary azeotrope containing both keys. The latter kind of operation is feasible only if condensation of the overhead vapor results in two liquid phases, one of which contains the bulk of one of the key components and the other contains the bulk of the entrainer. A t3q)ical scheme is shown in Fig. 3.10. The mixture (A -I- B) is fed to the column, and relatively pure A is taken from the column bottoms. A ternary azeotrope distilled overhead is condensed and separated into two liquid layers in the decanter. One layer contains a mixture of A -I- entrainer which is returned as reflux. The other layer contains relatively pure B. If the B layer contains a significant amount of entrainer, then this layer may need to be fed to an additional column to separate and recycle the entrainer and produce pure B. [Pg.81]

The second class of distillation operation using an extraneous mass-separating agent is extractive distillation. Here, the extraneous mass-separating agent is relatively involatile and is known as a solvent. This operation is quite different from azeotropic distillation in that the solvent is withdrawn from the column bottoms and does not form an azeotrope with any of the components. A typical extractive distillation process is shown in Fig. 3.11. ... [Pg.82]

Consider a three-product separation as in Fig. 5.11a in which the lightest and heaviest components are chosen to be the key separation in the first column. Two further columns are required to produce pure products (see Fig. 5.11a). However, note from Fig. 5.11a that the bottoms and overheads of the second and third columns are both pure B. Hence the second and third columns could simply be connected and product B taken as a sidestream (see Fig. 5.116). The arrangement in Fig. 5.116 is known as a prefractionator arrangement. Note that the first column in Fig. 5.116, the prefractionator, has a partial condenser to reduce the overall energy consumption. Comparing the prefractionator arrangement in Fig. 5.116 with the conventional... [Pg.148]

The final restriction of simple columns stated earlier was that they should have a reboiler and a total condenser. It is possible to use materials fiow to provide some of the necessary heat transfer by direct contact. This transfer of heat via direct contact is known as thermal coupling. [Pg.151]

Consider now thermal coupling of the prefractionator arrangement from Fig. 5.116. Figure 5.16a shows a prefi-actionator arrangement with partial condenser and reboiler on the prefractionator. Figure 5.166 shows the equivalent thermally coupled prefractionator arrangement sometimes known as a Petlyuk column. To make the two arrangements in Fig. 5.16 equivalent, the thermally coupled prefractionator requires extra plates to substitute for the prefractionator condenser and reboiler. [Pg.152]

This basic approach can be developed into a formal algorithm known as the problem table algorithm. To jllustrate the algorithm, it can be developed using the data from Fig. 6.2 given in Table 6.2 for AT ,i = 10°C. [Pg.175]

The shaded areas in Fig. 6.24, known as pockets, represent areas of additional process-to-process heat transfer. Remember that the profile of the grand composite curve represents residual heating and cooling demands after recovering heat within the shifted temperature intervals in the problem table algorithm. In these pockets in Fig. 6.24, a local surplus of heat in the process is used at temperature differences in excess of AT ,in to satisfy a local deficit. ... [Pg.186]

If the pressure drop available for the stream is known, the expressions of Polley et al. can be used. [Pg.219]

Once a design is known for the first two layers of the onion (i.e., reactors and separators only), the overall total cost of this design for all four layers of the onion (i.e., reactors, separators, heat exchanger network, and utilities) is simply the total cost of all reactors and separators (evaluated explicitly) plus the total cost target for heat exchanger network and utilities. [Pg.236]

If the composition of the waste stream is known, then the theoretical oxygen demand can be calculated from the appropriate stoichiometric equations. As a first level of approximation, we can assume that this theoretical oxygen demand would be equal to the COD. Then, experience with domestic sewage indicates that the average ratio of COD to BOD will be on the order 1.5 to 2. The following example will help to clarify these relationships. [Pg.309]

A third method of contact known as an anaerobic filter also uses upward flow but keeps the sludge in the digester by a physical barrier such as a grid. [Pg.316]


See other pages where Known is mentioned: [Pg.28]    [Pg.38]    [Pg.83]    [Pg.98]    [Pg.222]    [Pg.9]    [Pg.11]    [Pg.39]    [Pg.42]    [Pg.49]    [Pg.55]    [Pg.69]    [Pg.73]    [Pg.109]    [Pg.154]    [Pg.159]    [Pg.166]    [Pg.169]    [Pg.170]    [Pg.173]    [Pg.191]    [Pg.229]    [Pg.322]    [Pg.335]   
See also in sourсe #XX -- [ Pg.905 ]




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A Final Optimisation Phase, Known as the Safety Period

A SKETCH OF THE CHEMISTRY BEHIND KNOWN CARBON-BASED LIFE ON EARTH

All the concentrations at one reaction time are known

Applications to metal carbonyls with known heats of formation

ArC Known

Avoiding known threats

Biogenic sources known

Blank well-known

Boxes 1 How to make up an aqueous solution of known concentration from a solid chemical

Cancer known carcinogens

Carcinogenicity known carcinogens

Chemical carcinogens table listing 465 compounds known

Comparison of an experimental mean with a known value

Component Spectra, Known Concentrations

Confidence intervals known standard deviation

Dehydrogenases known structures

Detect Known Mutations

Drug-likeness mimicking known drugs

Effects well-known

Elements and Paraelements in Known Structures

Elements known from Time Immemorial

Elements known in antiquity

Elements known to ancients

Elements known to the ancient world

Estimates internal, precisely known

Examples of Metabolite Structure Determination from Known Biotransformations

Expression Patterns and Response to Known Drugs

Factors known

Glass-Reinforced Polyurethanes, a Well-Known Technology

Hit to Lead also Known as Closed Loop

How to make up an aqueous solution of known concentration from a solid chemical for use in quantitative analysis

If Analyte Structure Is Known

Indexing known unit cell

Initialization for a previously known identity

Inverse problem the source composition is known

Isozymes known genes

Known Compounds with Hematotoxic Potential

Known Coumarins

Known Descriptors of Paired Ligands

Known Deterministic Coupling

Known Effects of Ionic Forces in Polymers

Known Emission Spectra

Known Facts

Known Identities

Known Mechanisms

Known Polyacetylenic Compounds from Terrestrial Plants

Known Problems

Known Processes that Become Entirely Better or Otherwise Different

Known Since Antiquity

Known Small Heterocycles

Known Species)

Known Spectra, Uncoloured Species

Known Stochastic Coupling

Known acid-tolerant organisms

Known addition technique

Known adverse properties

Known chemical agents

Known community sphere

Known correlates

Known effects of Gulf War chemical exposures to the body

Known electrophilic aminating agents

Known function of time

Known good designs

Known good die

Known human carcinogens

Known human effects, definition

Known ligands

Known molecules

Known phototoxic agents

Known receptor

Known receptor sites

Known response

Known samples

Known subtraction technique

Known synthetic pathways

Known system behavior

Known to Cause Cancer in Humans

Known to or reasonably ascertainably

Known types of presolar grains

Known versus unknown unit cell dimensions

Known waveform

Knowns

Knowns

Less Known Redox-active Ligands in Metal Complexes

Liquid known substrate materials

Metabolomics known compounds

Microorganisms known microbes

Modeling Known Dependencies

Molecular modeling known receptors

Monoterpene alkaloids known

Multivariate normal known covariance matrix

National Toxicology Program known carcinogen list

Neurotoxicity known compounds

New and Known Polyacetylenes from Nature

Normal distribution with known mean

Normal distribution with known variance

Normally Distributed Observations with Known Mean

Obviousness of Combining Equivalents Together for Same Known Purpose

Occupational Exposures Known to be Carcinogenic

One Spectrum Known with Constant Logarithmic Slope

Other Anionic Rearrangements, Known and Unknown

Peptides staining with known sequences

Pigments with known chemical structure

Practical considerations and known limitations

Precious Stones Known Since Antiquity

Precursor Complexes of Known Structure

Predictions for Proteins with Known 3D Structure

Pregnancy drugs with known teratogenic effects

Processes Known, but not Used for Safety Reasons

Protein staining with known sequences

Protein structure known

Protein structure known folds

Reactions of Ions with Known Internal Energies

Reactions of Known Mechanism

Reactions with known invariant stoichiometry

Reduction known genome data

Representative insects known

Retinal degeneration with known metabolic causes

Sedimentary rocks, oldest known

Silicon Derivatives of Known Active Compounds

Solving Problems When Not All Equilibrium Concentrations Are Known

Some Applications Using Well-Known MOEAs

Some Well-Known Overall Reactions of Addition Polymers

Spatial transport with known scalar-dependent velocity

Substituting Equivalents Known for the Same Purpose

Survey of Known Five-Coordinate Pt(IV) Complexes

Surveys of Known Protein Structures

Tabulation of Known Acids and Alcohols

Testing for false positive predictions in membrane and soluble proteins of crystallographically known structure

The Known Anti-carbohydrate, Myeloma Immunoglobulins

The Lesser-Known Initial Members

The Number of Proteins Participating in a Pathway Is Known through Genetic Complementation Analysis

The rotation of plane-polarized light is known as optical activity

Transformations known with certainty

Traverses over known mineral deposits

Tuning Methods Based on Known Process Models

Tuning Procedure When Process Model Is Known

Tuning method known process models

Unserviceable Cylinders with Known Contents

Used Known Relative Atomic Masses to Create the Periodic Table

Well-Known Insecticides

Well-known hallucinogenic actions

What Is Well Known

What is the earliest known battery

When pH is Known

Where the Equilibrium Concentration of Ligand Not Known

Where the Equilibrium Concentration of Ligand is Known

Why Are Bombardier Beetles Known as Fire-Breathing Dragons

Why Is White Willow Bark Known as Natures Aspirin

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