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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. -
The Role of Hydrogen Bonding in Paracetamol–Solvent and Paracetamol–Hydrogel Matrix Interactions
materials Article The Role of Hydrogen Bonding in Paracetamol–Solvent and Paracetamol–Hydrogel Matrix Interactions Marta Miotke-Wasilczyk *, Marek Józefowicz * , Justyna Strankowska and Jerzy Kwela Insitute of Experimental Physics, Faculty of Mathematics, Physics and Informatics, University of Gda´nsk, Wita Stwosza 57, 80-308 Gda´nsk,Poland; [email protected] (J.S.); [email protected] (J.K.) * Correspondence: [email protected] (M.M.-W.); [email protected] (M.J.) Abstract: The photophysical and photochemical properties of antipyretic drug – paracetamol (PAR) and its two analogs with different substituents (acetanilide (ACT) and N-ethylaniline (NEA)) in 14 solvents of different polarity were investigated by the use of steady–state spectroscopic technique and quantum–chemical calculations. As expected, the results show that the spectroscopic behavior of PAR, ACT, and NEA is highly dependent on the nature of the solute–solvent interactions (non- specific (dipole-dipole) and specific (hydrogen bonding)). To characterize these interactions, the multiparameter regression analysis proposed by Catalán was used. In order to obtain a deeper insight into the electronic and optical properties of the studied molecules, the difference of the dipole moments of a molecule in the ground and excited state were determined using the theory proposed by Lippert, Mataga, McRae, Bakhshiev, Bilot, and Kawski. Additionally, the influence of the solute polarizability on the determined dipole moments was discussed. The results of the solvatochromic studies were related to the observations of the release kinetics of PAR, ACT, and NEA from polyurethane hydrogels. The release kinetics was analyzed using the Korsmayer-Peppas and Hopfenberg models. -
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. -
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, -
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. -
Solvent Dependent Absorption and Fluorescence Ofaketocyanine Dye
Indian Journal of Chemistry Vol. 34A, February 1995, pp. 94-101 Solvent dependent absorption and fluorescence of a ketocyanine dye in neat and binary mixed solvents Debashis Banerjee, Ashis Kumar Laha & Sanjib Bagchi" Department of Chemistry, Burdwan University, Burdwan 713 104, India Received 11 March 1994; revised and accepted 23 September 1994 The environmental effect on the ground and excited state properties of a ketocyanine dye has been studied by monitoring its absorption and fluorescence characteristics in various pure and bi- nary mixed solvents. The spectroscopic transition leading to the longest wavelength absorption or fluorescence has been found to involve considerable intramolecular charge transfer as evidenced by semiempirical MO calculations at the AMI level. Ground state complexation is indicated in protic solvents, aromatic hydrocarbons and cyclic ethers. The fluorescence maximum, E (F), shows a corre- lation with ET (30) scale of solvent polarity. A multiple linear correlation of E(F) with Kamlet-Taft parameter representing solvent dipolarity (n*) and hydrogen bonding ability (a and (3) suggests that apart from dipolar interactions specific solute-solvent interactions are important in determining flu- orescence maxima. Study of E (F) in mixed binary solvents points to a preferential solvation of the solute in the S 1 state. The polarity probes have found extensive applic- nine dye in pure and mixed binary solvents by ations during the last couple of years, especially monitoring its longest wavelength absorption and for the evaluation of various microenvironrnental fluorescence band. The dye chosen for the pre- properties 1-5. Although a large number of miCTOP- sent study is (1-1 ),(9-1)-di-l ,9-di-(2,3-dihydroindo- olarity reporters involving solvatochromic spectral lyl)- 4,6-dimethylene- nona-l,3,6,8-tetraene-5-one transition are known, e.g., 4-methoxycarbonylpyri- (Fig. -
Acid Dissociation Constant - Wikipedia, the Free Encyclopedia Page 1
Acid dissociation constant - Wikipedia, the free encyclopedia Page 1 Help us provide free content to the world by donating today ! Acid dissociation constant From Wikipedia, the free encyclopedia An acid dissociation constant (aka acidity constant, acid-ionization constant) is an equilibrium constant for the dissociation of an acid. It is denoted by Ka. For an equilibrium between a generic acid, HA, and − its conjugate base, A , The weak acid acetic acid donates a proton to water in an equilibrium reaction to give the acetate ion and − + HA A + H the hydronium ion. Key: Hydrogen is white, oxygen is red, carbon is gray. Lines are chemical bonds. K is defined, subject to certain conditions, as a where [HA], [A−] and [H+] are equilibrium concentrations of the reactants. The term acid dissociation constant is also used for pKa, which is equal to −log 10 Ka. The term pKb is used in relation to bases, though pKb has faded from modern use due to the easy relationship available between the strength of an acid and the strength of its conjugate base. Though discussions of this topic typically assume water as the solvent, particularly at introductory levels, the Brønsted–Lowry acid-base theory is versatile enough that acidic behavior can now be characterized even in non-aqueous solutions. The value of pK indicates the strength of an acid: the larger the value the weaker the acid. In aqueous a solution, simple acids are partially dissociated to an appreciable extent in in the pH range pK ± 2. The a actual extent of the dissociation can be calculated if the acid concentration and pH are known. -
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. -
Fundamental Insights Into the Dissolution and Precipitation of Cellulosic Biomass from Ionic Liquid Mixtures
Fundamental Insights into the Dissolution and Precipitation of Cellulosic Biomass from Ionic Liquid Mixtures By David L. Minnick Submitted to the graduate degree program in Chemical and Petroleum Engineering and the Graduate Faculty of the University of Kansas in partial fulfillment of the requirements for the degree of Doctor of Philosophy. ________________________________ Chairperson: Aaron M. Scurto ________________________________ Bala Subramaniam ________________________________ Raghunath V. Chaudhari ________________________________ Laurence Weatherley ________________________________ Belinda Sturm Date Defended: July, 14th 2016 The Dissertation Committee for David L. Minnick certifies that this is the approved version of the following dissertation: Fundamental Insights into the Dissolution and Precipitation of Cellulosic Biomass from Ionic Liquid Mixtures ________________________________ Chairperson: Aaron M. Scurto Date approved: July, 22nd 2016 ii Abstract Ionic liquids (ILs) are a unique class of molecular salts that melt at temperatures below 100oC. The ionic functionality of ILs provide this class of molecules numerous advantages for applications in reactions, separations, and materials processing due to their molecular flexibility through cation/anion selection. Additionally, ionic liquids possess negligible vapor pressures and may lead to more sustainable or “green” processes by eliminating solvent-based air pollution. For these reasons ionic liquids are being targeted for implementation in a range of industrial processes as sustainable solvent technologies. The primary objective of this dissertation targets the application of ionic liquids to cellulosic biomass processing. For instance, chemical processing of biomass remains a challenge as the rigid inter- and intra- molecular hydrogen bonding network of cellulose renders it insoluble in nearly all aqueous and organic solvents. Alternatively, select ionic liquids (ILs) are capable of dissolving significant quantities. -
The Pennsylvania State University the Graduate School Department
The Pennsylvania State University The Graduate School Department of Chemistry STUDY OF SOLVATION EFFECTS IN POLAR-PROTIC SOLVENTS USING COMPUTER SIMULATIONS A Thesis in Chemistry by Scot Richard Mente Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy May 1999 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 9938021 UMI Microform 9938021 Copyright 1999, by UMI Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. UMI 300 North Zeeb Road Ann Arbor, MI 48103 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. We approve the thesis of Scot Richard Mente. Date of Signature Mark Maroncelli Professor of Chemistry Thesis Advisor Chair of Committee Professor of Vy/v Desjarlais Assistant Professor of Chemistry z/'+n 1 tong-Qing Associate Professor of Materials Science and Engineering f o si tin Peter C. Jurs( Professor of Chemistry Acting Head of the Department of Chemistry Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT Computational chemistry techniques are used to study various aspects of solvation and solvent effects in polar-protic systems. A variety of methods have been utilized, including Monte Carlo and molecular dynamics simulations, as well as semi-empirical and ab initio calculations. The first part of this thesis examines the solvent catalyzed proton transfer reaction in 7-Azaindole and 1 -Azacarbazole. In Chapter 2 classical Monte Carlo and molecular dynamics simulations are used to examine the structure and dynamics of solvation of aza- aromatic solutes in alcohol and water solvents in an effort to determine whether the existing interpretations of the solvent participation in these reactions are reasonable. -
Review of Extraction Techniques
International Journal of Advanced Research in Chemical Science (IJARCS) Volume 6, Issue 3, 2019, PP 6-21 ISSN No. (Online) 2349-0403 DOI: http://dx.doi.org/10.20431/2349-0403.0603002 www.arcjournals.org Review of Extraction Techniques Extraction Methods: Microwave, Ultrasonic, Pressurized Fluid, Soxhlet Extraction, Etc Komal Patel1, Namrata Panchal2, Dr. Pradnya Ingle3* 3Associate Professor Department of Chemical Engineering, Shivajirao S. Jondhale College of Engineering, Dombivli (East), 421201, University of Mumbai, India. *Corresponding Author: Dr. Pradnya Ingle, Associate Professor Department of Chemical Engineering, Shivajirao S. Jondhale College of Engineering, Dombivli (East), 421201, University of Mumbai, India. Abstract: In recent years, variety of Extraction techniques has been introduced for the recovery of organic compounds. Extraction Methods are widely used in various Industries for Separation of components and has wide range of applications. Details of basic theories applicable to types of Extraction such as - Liquid- Liquid Extraction, Solid Phase Extraction, Solid Liquid Extraction and Supercritical Extraction, etc. including the choice of solvent, procedure, respective advantages disadvantages and their applications are explained. Finally, the specific extraction techniques such as Microwave Extraction, Ultrasonic Extraction, Pressurized Fluid Extraction and Soxhlet Extraction along with their applications are also explained. Keywords: Extraction, Liquid-Liquid Extraction, Solid Phase Extraction, Solid Liquid Extraction, -
Solvent Supercritical Fluid Technologies to Extract Bioactive Compounds from Natural Sources: a Review
molecules Review Solvent Supercritical Fluid Technologies to Extract Bioactive Compounds from Natural Sources: A Review Kooi-Yeong Khaw ID , Marie-Odile Parat ID , Paul Nicholas Shaw ID and James Robert Falconer * School of Pharmacy, Pharmacy Australia Centre of Excellence, University of Queensland, Brisbane, QLD 4102, Australia; [email protected] (K.-Y.K.); [email protected] (M.-O.P.); [email protected] (P.N.S.) * Correspondence: [email protected]; Tel.: +86-10-8210-8797 Received: 16 June 2017; Accepted: 12 July 2017; Published: 14 July 2017 Abstract: Supercritical fluid technologies offer a propitious method for drug discovery from natural sources. Such methods require relatively short processing times, produce extracts with little or no organic co-solvent, and are able to extract bioactive molecules whilst minimising degradation. Supercritical fluid extraction (SFE) provides a range of benefits, as well as offering routes to overcome some of the limitations that exist with the conventional methods of extraction. Unfortunately, SFE-based methods are not without their own shortcomings; two major ones being: (1) the high establishment cost; and (2) the selective solvent nature of CO2, i.e., that CO2 only dissolves small non-polar molecules, although this can be viewed as a positive outcome provided bioactive molecules are extracted during solvent-based SFE. This review provides an update of SFE methods for natural products and outlines the main operating parameters for extract recovery. Selected processing considerations are presented regarding supercritical fluids and the development and application of ultrasonic-assisted SFE methods, as well as providing some of the key aspects of SFE scalability.