DOCSLIB.ORG

Lecture-14.Pdf

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Lecture-14.Pdf Separation • Samples are usually complex mixtures. In order to identify and quantify the components of a Ch. 23 Fundamentals of Analytical mixture, we have to separate the components in Separations the mixture. • Separation methods – Extraction – Chromatography – Electrophoresis Solvent Extraction Solvent Extraction • The transfer of an analyte from [S]2 (1− q ) m / V2 one phase to a second based on K = = the relative solubility of the []S 1 qm/ V1 analyte in two immiscible liquids. Fraction remaining in V ’ q = 1 phase 1 after 1 extraction V+ KV [S]2 (1− q ) m / V2 1 2 K = = n []S 1 qm/ V1 Fraction remaining in V ’ n 1 phase 1 after n extractions q= q&)')( ⋅ q ⋅... q = K: the partition coefficient for distribution of S between n V1 + KV2 the two phases at equilibrium; If q = 1/4, then 1/4 remains in phase 1 after one extraction m: the moles of S in the system K: the partition coefficient; q: the fraction of S remaining in q: the fraction of S remaining in phase 1; phase 1; n: the # of extractions. Extraction Efficiency pH Effects • A solute S has a partition coefficient of 3 between • The charge changes of an acid or base as the pH is toluene and water. If you have 100 mL of a 0.010 M changed. solution of S in water.(1)What fraction of the solute • Distribute coefficient (D): an alternate form of the remains in H2O after a 500 mL extraction with toluene? partition coefficient. (2) What fraction of the solute remains in H O after a 5- 2 Total conc. in phase 2 C 100 mL extractions with toluene? D = = 2 Total conc. in phase 1 C 100 1 q = =0.062 ≈ 6% • A basic amine whose neutral form, B, has partition 100+ (3)(500) coefficient, K, between phases 1 and 2. The conjugated 5 acid BH+ is soluble only in phase 1 and the acid 100 ’ q = =0.00098 ≈ 0.1% dissociation constant is Ka. 100+ (3)(100) [B] [B] [H + ] It is more efficient to do several small extractions 2 1 K = ; Ka = + than one big extraction. []B 1 []BH 1 1 pH Effects pH Effects + -9 Total conc. in phase 2 C [B] [H + ] [B] • K for an amine B is 3.0 and the Ka for BH is 1.0×10 . If D = = 2 Ka = 1 K = 2 50.00 mL of 0.010 M aqueous amine is extracted with 100 Total conc. in phase 1 C []BH + []B 1 1 1 mL of solvent, calculate the % remaining the in aqueous phase in M at (1) pH 10.00; (2) pH 8.00. [B]2 KKa D = = = Kα −9 [][][]B BH + Ka H + B KKa 3.0× 1.0× 10 1 + 1 + pH =10.00: D = = = 2.73 Ka+[] H + 1.0× 10−9 + 1.0 × 10−10 V 50 + 1 []HA 2 KH[] q = = = 0.15 15% D = = = Kα HA − + V1 + DV2 50+ 2.73 × 100 [][]HA1 + A 1 Ka+[] H −9 − + KKa 3.0× 1.0 × 10 [][]AH1 []HA 2 pH =8.00 : D = = = 0.273 (Ka = ; K = ) Ka+[] H + 1.0× 10−9 + 1.0 × 10−8 []HA 1 []HA 1 V 50 1 : fraction of the species (P.191) q = = = 0.65 65% V1 + DV2 50+ 0.273 × 100 pH Effects Extraction with a Metal Chelator • The weak acid HA with Ka = 1.0×10-5 is to be quantitatively extracted from an aqueous sample (100 mL sample volume) using 100 mL of a suitable organic solvent, by doing a single •Usually neutral complexes can be extracted into organic extraction. The partition coefficient is 30.0. What is the solvents. Charged complexes (e.g. MEDTA2-) are not very maximum pH allowed in order that no more than 5% of the acid soluble in organic solvents. remains in the aqueous solution? •Commonly used: dithizone, 8-hydroquinoline, and V 100 cupferron. q = 1 = = 5% V1 + DV2 100 +D ×100 D = 19 KH[]+ 30.0× [H + ] D = = = 19 Ka+ [] H + 1.0× 10−5 + [H + ] [H + ]= 1.73 × 10−5 M pH = 4.76 Extraction with a Metal Chelator Extraction with a Metal Chelator •Commonly used: dithizone, 8-hydroquinoline, and cupferron. •Each ligand can be presented •Crown ethers can extract alkali metal ions and can bring as a weak acid, HL. them into non-polar solvents. •Mn+ is in the aqueous phase and MLn is in the organic phase •The distribution coefficient (D) for metal ion extraction depends on pH and [ligand]. •By select a pH, you can bring the metal into either phase. 2 Chromatography Type of Chromatography • A separation process based on the various partitioning coefficients of different solutes between the two phases. • Based on the mechanism of interaction of the solute • Involving the interaction of solute(s) and two phases; operates on with the stationary phase the same principle as extraction, but one phase is held in place while the other moves past it. • Mobile phase: A gas or liquid that moves through the column. (1) Adsorption chromatography - Solute is adsorbed on the surface of • Stationary phase: A solid or liquid that remains in place. the stationary phase (solid). - The stronger a solute adsorbs, the longer it takes to travel through the chromatography column Type of Chromatography Type of Chromatography • Based on the mechanism of interaction of the solute • Based on the mechanism of interaction of the solute with the stationary phase with the stationary phase (2) Partition chromatography (3) Ion-exchange chromatography - GC -Retention is based on the - the partitioning of solutes attraction between solute ions and between a mobile phase (gas) charged sites bound to the and bonded liquid stationary stationary phase (ionic phase interactions to separate ions). - A stationary phase of cations will separate anions and vice versa. Type of Chromatography Type of Chromatography • Based on the mechanism of interaction of the solute • Based on the mechanism of interaction of the solute with the stationary phase with the stationary phase (5) Affinity chromatography -Specific interactions of one kind of solute molecule to a second (4) Molecular Size exclusion molecular that is covalently attached to the stationary phase chromatography -Most selective (e.g. use antibodies to select out one protein from a -size exclusion, gel filtration, or gel mixture of hundreds) permeation chromatography -separate molecules by size -large molecules pass through faster (they do not get caught up in pores) 3.
Load more

Recommended publications
  • Understanding Variation in Partition Coefficient, Kd, Values: Volume II
    United States Office of Air and Radiation EPA 402-R-99-004B Environmental Protection August 1999 Agency UNDERSTANDING VARIATION IN PARTITION COEFFICIENT, Kd, VALUES Volume II: Review of Geochemistry and Available Kd Values for Cadmium, Cesium, Chromium, Lead, Plutonium, Radon, Strontium, Thorium, Tritium (3H), and Uranium UNDERSTANDING VARIATION IN PARTITION COEFFICIENT, Kd, VALUES Volume II: Review of Geochemistry and Available Kd Values for Cadmium, Cesium, Chromium, Lead, Plutonium, Radon, Strontium, Thorium, Tritium (3H), and Uranium August 1999 A Cooperative Effort By: Office of Radiation and Indoor Air Office of Solid Waste and Emergency Response U.S. Environmental Protection Agency Washington, DC 20460 Office of Environmental Restoration U.S. Department of Energy Washington, DC 20585 NOTICE The following two-volume report is intended solely as guidance to EPA and other environmental professionals. This document does not constitute rulemaking by the Agency, and cannot be relied on to create a substantive or procedural right enforceable by any party in litigation with the United States. EPA may take action that is at variance with the information, policies, and procedures in this document and may change them at any time without public notice. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government. ii FOREWORD Understanding the long-term behavior of contaminants in the subsurface is becoming increasingly more important as the nation addresses groundwater contamination. Groundwater contamination is a national concern as about 50 percent of the United States population receives its drinking water from groundwater.
    [Show full text]
  • Henry's Law Constants and Micellar Partitioning of Volatile Organic
    38 J. Chem. Eng. Data 2000, 45, 38-47 Henry’s Law Constants and Micellar Partitioning of Volatile Organic Compounds in Surfactant Solutions Leland M. Vane* and Eugene L. Giroux United States Environmental Protection Agency, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268 Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor- liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace experiments were performed to quantify the effect of four anionic surfactants and one nonionic surfactant on the Henry’s law constants of 1,1,1-trichloroethane, trichloroethylene, toluene, and tetrachloroethylene at temperatures ranging from 30 to 60 °C. Although the Henry’s law constant increased markedly with temperature for all solutions, the amount of VOC in micelles relative to that in the extramicellar region was comparatively insensitive to temperature. The effect of adding sodium chloride and isopropyl alcohol as cosolutes also was evaluated. Significant partitioning of VOCs into micelles was observed, with the micellar partitioning coefficient (tendency to partition from water into micelle) increasing according to the following series: trichloroethane < trichloroethylene < toluene < tetrachloroethylene. The addition of surfactant was capable of reversing the normal sequence observed in Henry’s law constants for these four VOCs. Introduction have long taken advantage of the high Hc values for these compounds. In the engineering field, the most common Vast quantities of organic solvents have been disposed method of dealing with chlorinated solvents dissolved in of in a manner which impacts human health and the groundwater is “pump & treat”swithdrawal of ground- environment.
    [Show full text]
  • Extraction Methods and Their Influence on Yield When Extracting Thermo-Vacuum-Modified Chestnut Wood
    Article Extraction Methods and Their Influence on Yield When Extracting Thermo-Vacuum-Modified Chestnut Wood Maurizio D’Auria 1 , Marisabel Mecca 1, Maria Roberta Bruno 2 and Luigi Todaro 2,* 1 Department of Science, University of Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy; [email protected] (M.D.); [email protected] (M.M.) 2 School of Agricultural Forestry, Food, and Environmental Science, University of Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-3478782534 Abstract: Improvements in the yield and solubility of chestnut wood extractives, by using different extraction methods and molybdenum catalysts as support, have rarely been reported in literature. Many studies focus on the different parts of trees, except for the chemical characteristics of the remaining extractives achieved from thermally modified (THM) chestnut (Castanea sativa Mill) wood. This research seeks to better understand the effects of extraction techniques and catalysts on the yield and solubility of extractives. GC-MS analysis of the chloroform soluble and insoluble fractions was also used. Accelerated Solvent Extraction (ASE) 110 ◦C, Soxhlet, and autoclave extraction techniques were used to obtain extractives from untreated and thermally modified (THM) chestnut ◦ wood (170 C for 3 h). Ethanol/H2O, ethanol/toluene, and water were the solvents used for each technique. A polyoxometalate compound (H3PMo12O40) and MoO3 supported on silica were used as catalysts. The THM induced a change in the wood’s surface color (DE = 21.5) and an increase in mass loss (5.9%), while the equilibrium moisture content (EMC) was reduced by 17.4% compared to the control wood.
    [Show full text]
  • Chapter 4: Aqueous Solutions (Chs 4 and 5 in Jespersen, Ch4 in Chang)
    Chapter 4: Aqueous Solutions (Chs 4 and 5 in Jespersen, Ch4 in Chang) Solutions in which water is the dissolving medium are called aqueous solutions. There are three major types of chemical processes occurring in aqueous solutions: precipitation reactions (insoluble product) acid-base reactions (transfer of H+s) redox reactions (transfer of electrons) General Properties of Aqueous Solutions solution – a homogeneous mixture of two or more substances. solvent – usually the component that is present in greater quantity. solute(s) – the other substance(s) in the solution (ionic or molecular); present in smaller quantities. saturated solution – at a given temperature, the solution that results when the maximum amount of a substance has dissolved in a solvent. AJR Ch4 Aqueous Solutions.docx Slide 1 Electrolytic Properties electrolyte – a substance whose aqueous solutions contains ions and hence conducts electricity. E.g. NaCl. nonelectrolyte – a substance that does not form ions when it dissolves in water, and so aqueous solutions of nonelectrolytes do not conduct electricity. E.g. Glucose, C6H12O6. CuSO4 and Water; Ions present; Sugar and Water; No Ions present; electricity is conducted – bulb on. electricity is not conducted – bulb off. AJR Ch4 Aqueous Solutions.docx Slide 2 Ionic Compounds in Water Ionic compounds dissociate into their component ions as they dissolve in water. The ions become hydrated. Each ion is surrounded by water molecules, with the negative pole of the water oriented towards the cation and the positive pole oriented towards the anion. Other examples of ionic compounds dissociating into their component ions: + 2– Na2CO3 → 2 Na (aq) + CO3 (aq) + 2– (NH4)2SO4 → 2 NH4 (aq) + SO4 (aq) AJR Ch4 Aqueous Solutions.docx Slide 3 Molecular Compounds in Water Most molecular compounds do not form ions when they dissolve in water; they are nonelectrolytes.
    [Show full text]
  • Drugs and Acid Dissociation Constants Ionisation of Drug Molecules Most Drugs Ionise in Aqueous Solution.1 They Are Weak Acids Or Weak Bases
    Drugs and acid dissociation constants Ionisation of drug molecules Most drugs ionise in aqueous solution.1 They are weak acids or weak bases. Those that are weak acids ionise in water to give acidic solutions while those that are weak bases ionise to give basic solutions. Drug molecules that are weak acids Drug molecules that are weak bases where, HA = acid (the drug molecule) where, B = base (the drug molecule) H2O = base H2O = acid A− = conjugate base (the drug anion) OH− = conjugate base (the drug anion) + + H3O = conjugate acid BH = conjugate acid Acid dissociation constant, Ka For a drug molecule that is a weak acid The equilibrium constant for this ionisation is given by the equation + − where [H3O ], [A ], [HA] and [H2O] are the concentrations at equilibrium. In a dilute solution the concentration of water is to all intents and purposes constant. So the equation is simplified to: where Ka is the acid dissociation constant for the weak acid + + Also, H3O is often written simply as H and the equation for Ka is usually written as: Values for Ka are extremely small and, therefore, pKa values are given (similar to the reason pH is used rather than [H+]. The relationship between pKa and pH is given by the Henderson–Hasselbalch equation: or This relationship is important when determining pKa values from pH measurements. Base dissociation constant, Kb For a drug molecule that is a weak base: 1 Ionisation of drug molecules. 1 Following the same logic as for deriving Ka, base dissociation constant, Kb, is given by: and Ionisation of water Water ionises very slightly.
    [Show full text]
  • Method 3520C: Continuous Liquid-Liquid Extraction, Part of Test
    METHOD 3520C CONTINUOUS LIQUID-LIQUID EXTRACTION 1.0 SCOPE AND APPLICATION 1.1 This method describes a procedure for isolating organic compounds from aqueous samples. The method also describes concentration techniques suitable for preparing the extract for the appropriate determinative steps described in Sec. 4.3 of Chapter Four. 1.2 This method is applicable to the isolation and concentration of water-insoluble and slightly soluble organics in preparation for a variety of chromatographic procedures. 1.3 Method 3520 is designed for extraction solvents with greater density than the sample. Continuous extraction devices are available for extraction solvents that are less dense than the sample. The analyst must demonstrate the effectiveness of any such automatic extraction device before employing it in sample extraction. 1.4 This method is restricted to use by or under the supervision of trained analysts. Each analyst must demonstrate the ability to generate acceptable results with this method. 2.0 SUMMARY OF METHOD 2.1 A measured volume of sample, usually 1 liter, is placed into a continuous liquid-liquid extractor, adjusted, if necessary, to a specific pH (see Table 1), and extracted with organic solvent for 18 - 24 hours. 2.2 The extract is dried, concentrated (if necessary), and, as necessary, exchanged into a solvent compatible with the cleanup or determinative method being employed (see Table 1 for appropriate exchange solvents). 3.0 INTERFERENCES 3.1 Refer to Method 3500. 3.2 The decomposition of some analytes has been demonstrated under basic extraction conditions required to separate analytes. Organochlorine pesticides may dechlorinate, phthalate esters may exchange, and phenols may react to form tannates.
    [Show full text]
  • Partition Coefficients in Mixed Surfactant Systems
    Partition coefficients in mixed surfactant systems Application of multicomponent surfactant solutions in separation processes Vom Promotionsausschuss der Technischen Universität Hamburg-Harburg zur Erlangung des akademischen Grades Doktor-Ingenieur genehmigte Dissertation von Tanja Mehling aus Lohr am Main 2013 Gutachter 1. Gutachterin: Prof. Dr.-Ing. Irina Smirnova 2. Gutachterin: Prof. Dr. Gabriele Sadowski Prüfungsausschussvorsitzender Prof. Dr. Raimund Horn Tag der mündlichen Prüfung 20. Dezember 2013 ISBN 978-3-86247-433-2 URN urn:nbn:de:gbv:830-tubdok-12592 Danksagung Diese Arbeit entstand im Rahmen meiner Tätigkeit als wissenschaftliche Mitarbeiterin am Institut für Thermische Verfahrenstechnik an der TU Hamburg-Harburg. Diese Zeit wird mir immer in guter Erinnerung bleiben. Deshalb möchte ich ganz besonders Frau Professor Dr. Irina Smirnova für die unermüdliche Unterstützung danken. Vielen Dank für das entgegengebrachte Vertrauen, die stets offene Tür, die gute Atmosphäre und die angenehme Zusammenarbeit in Erlangen und in Hamburg. Frau Professor Dr. Gabriele Sadowski danke ich für das Interesse an der Arbeit und die Begutachtung der Dissertation, Herrn Professor Horn für die freundliche Übernahme des Prüfungsvorsitzes. Weiterhin geht mein Dank an das Nestlé Research Center, Lausanne, im Besonderen an Herrn Dr. Ulrich Bobe für die ausgezeichnete Zusammenarbeit und der Bereitstellung von LPC. Den Studenten, die im Rahmen ihrer Abschlussarbeit einen wertvollen Beitrag zu dieser Arbeit geleistet haben, möchte ich herzlichst danken. Für den außergewöhnlichen Einsatz und die angenehme Zusammenarbeit bedanke ich mich besonders bei Linda Kloß, Annette Zewuhn, Dierk Claus, Pierre Bräuer, Heike Mushardt, Zaineb Doggaz und Vanya Omaynikova. Für die freundliche Arbeitsatmosphäre, erfrischenden Kaffeepausen und hilfreichen Gespräche am Institut danke ich meinen Kollegen Carlos, Carsten, Christian, Mohammad, Krishan, Pavel, Raman, René und Sucre.
    [Show full text]
  • Estimation of Distribution Coefficients from the Partition Coefficient and Pka Douglas C
    Estimation of Distribution Coefficients from the Partition Coefficient and pKa Douglas C. Scott* and Jeffrey W. Clymer he use of partition coefficients has received much atten- tion in the assessment of relative lipophilicity and hy- drophilicity of a compound. Recent advances in com- putational chemistry have enabled scientists to estimate Tpartition coefficients for neutral species very easily. For ioniz- able species, the distribution coefficient is a more relevant pa- rameter; however, less effort has been applied to its assessment. Knowledge of the distribution coefficient and pKa is important The authors discuss for the basic characterization of a compound (1), particularly the relationship when assessing the compound’s potential to penetrate biolog- between the partition ical or lipid barriers (2). In addition, the majority of compounds coefficient and the are passively absorbed and a large number of new chemical en- distribution coefficient tities fail in the development stages because of related phar- and relate the two with the use of equations. macokinetic reasons (3). Assessing a compound’s relative lipophilicity dictates a formulation strategy that will ensure ab- To accurately explain this relationship, the sorption or tissue penetration, which ultimately will lead to de- authors consider the partitioning of both the livery of the drug to the site of action. In recognition of the ionized and un-ionized species.The presence value of knowing the extent of a drug’s gastrointestinal per- of both species in the oil phase necessitates a meation along with other necessary parameters, FDA has is- dissociative equilibrium among these species sued guidance for a waiver of in vivo bioavailability and bio- such as that in the water phase.
    [Show full text]
  • A Review of Supercritical Fluid Extraction
    NAT'L INST. Of, 3'«™ 1 lY, 1?f, Reference NBS PubJi- AlllDb 33TA55 cations /' \ al/l * \ *"»e A U O* * NBS TECHNICAL NOTE 1070 U.S. DEPARTMENT OF COMMERCE / National Bureau of Standards 100 LI5753 No, 1070 1933 NATIONAL BUREAU OF STANDARDS The National Bureau of Standards' was established by an act of Congress on March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau's technical work is per- formed by the National Measurement Laboratory, the National Engineering Laboratory, and the Institute for Computer Sciences and Technology. THE NATIONAL MEASUREMENT LABORATORY provides the national system ot physical and chemical and materials measurement; coordinates the system with measurement systems of other nations and furnishes essential services leading to accurate and uniform physical and chemical measurement throughout the Nation's scientific community, industry, and commerce; conducts materials research leading to improved methods of measurement, standards, and data on the properties of materials needed by industry, commerce, educational institutions, and Government; provides advisory and research services to other Government agencies; develops,
    [Show full text]
  • 2.1.2 Extractive Crystallization
    EUROPEAN ROADMAP OF PROCESS INTENSIFICATION - TECHNOLOGY REPORT - TECHNOLOGY: EXTRACTIVE CRYSTALLIZATION TECHNOLOGY CODE: 2.1.2 AUTHOR: Mark Roelands, TNO Science & Industry, Delft, Netherlands Table of contents 1. Technology 1.1 Description of technology / working principle 1.2 Types and “versions” 1.3 Potency for Process Intensification: possible benefits 1.4 Stage of development 2. Applications 2.1 Existing technology (currently used) 2.2 Known commercial applications 2.3 Known demonstration projects 2.4 Potential applications discussed in literature 3. What are the development and application issues? 3.1 Technology development issues 3.2 Challenges in developing processes based on the technology 4. Where can information be found? 4.1 Key publications 4.2 Relevant patents and patent holders 4.3 Institutes/companies working on the technology 5. Stakeholders 5.1 Suppliers/developers 5.2 End-users 6. Expert’s brief final judgment on the technology 1 1. Technology 1.1 Description of technology / working principle (Feel free to modify/extend the short technology description below) Extractive crystallization is a hybrid process in which crystallization and extraction are combined. There are several process configurations possible. Either the solute or the solvent can be extracted from a solution. In case the solute is extracted, the solute accumulates in the extractant until this phase becomes supersaturated and crystallization starts. In one configuration a reactive extractant is applied. Subsequently the crystals are separated from the mother liquor. In this case the crystal are the desired product. In a second configuration absorption of a compound from a gas stream into a reactive extractant takes place, followed by crystallization of one of the compounds.
    [Show full text]
  • 1 Supplementary Material to the Paper “The Temperature and Pressure Dependence of Nickel Partitioning Between Olivine and Sili
    SUPPLEMENTARY MATERIAL TO THE PAPER “THE TEMPERATURE AND PRESSURE DEPENDENCE OF NICKEL PARTITIONING BETWEEN OLIVINE AND SILICATE MELT” A. K. Matzen, M. B. Baker, J. R. Beckett, and E. M. Stolper. In this Supplement, we provide seven sections that expand and/or illustrate specific topics presented in the main text. The first section is a sample calculation using our preferred partitioning expression, equation (5), from the main text. Section 2 compares our fitted values of ∆ r HT ,P ∆ r ST ,P − ref ref and ref ref for equation (5) to those calculated using tabulated thermodynamic R R data. In Section 3, we present details of the mass-balance calculations used to evaluate the experiments from both this work and the literature, and in Section 4 we describe in detail the construction of the Filter-B dataset. Section 5 details the construction and fits of the regular solution partitioning models. Section 6 is a comparison of the results of this work and the Beattie-Jones family of models. Finally, Section 7 lists all of the references incorporated into our database on olivine-liquid Ni partitioning. 1. EXAMPLE CALCULATION USING OUR PREFERRED PARTITIONING EXPRESSION (EQUATION 5) FROM THE MAIN TEXT Although one of the simplest equations listed in the text, we think it useful to present a detailed accounting of how to use equation (5) along with the fitted parameters presented in Table 4 to ol /liq ol /liq ol liq predict DNi (where DNi = NiO /NiO , by wt.) given the temperature and compositions of the coexisting olivine and liquid. In our example calculation, we predict the partition coefficient for one of our 1.0 GPa experiments, Run 6.
    [Show full text]
  • Liquid-Liquid Extraction Technology
    Liquid-Liquid Extraction Technology 0610 4501 Liquid-Liquid Extraction Technology at Sulzer Chemtech Sulzer Chemtech, a member of the Sulzer Corporation, with headquarters in Winterthur, Switzerland, is active in the field of process engineering, employing 3’000 persons worldwide. Sulzer Chemtech is represented in all important industrial countries setting standards in the field of mass transfer and static mixing with its advanced and economical solutions. Sulzer Chemtech is organized into four business units, one of which is the Process Technology group. This business unit was formed in early 2009 following the acquisition of Kühni, a Swiss company with more than 75 years experience in innovative separation processes. Today, Sulzer Chemtech Process Technology is headquartered in Allschwil (Basel), Switzerland. We provide a unique and wide portfolio of separation and application technologies, amongst which liquid-liquid extraction. Working Principle Fields of Application Liquid-liquid extraction is an important the liquids are transported countercur- Liquid-liquid extraction is a complex sepa- separation technology, with a wide range rently. The viscosity and interfacial tension ration process. An additional component of applications in the modern process in- are additional important parameters. has to be introduced as extractant, which dustry. The extraction process is based on makes other subsequent separation steps In nearly all liquid-liquid extraction pro- different solubilities of components in two necessary. Therefore, liquid-liquid extrac- cesses one of the liquids is dispersed into immiscible, or partially miscible, liquids. tion is mostly used when separation of the second liquid in the form of droplets. The components that need to be recov- components by distillation is either un- The key for a high process performance ered are extracted from the feed stream economical, or even impossible.
    [Show full text]