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Recent Extraction Techniques with Emphasis on Supercritical Fluid Extraction and Microwave-assisted Extraction

Sparr Eskilsson, Cecilia LU (2003)
Abstract (Swedish)
Popular Abstract in Swedish

För att kunna mäta ett ämnes halt i ett prov behövs en analysmetod. Det första steget i en analysmetod innefattar provupparbetning. Med det menas att ämnet man vill mäta halten av avskiljs (extraheras) från provet med någon sorts extraktionsteknik. I laboratorier världen över görs dagligen många analytiska extraktioner. Det kan handla om t.ex. livsmedelsanalyser, miljöanalyser eller medicinska analyser. I de flesta laboratorier utförs analyserna med extraktionstekniker, som är mycket tidskrävande (vanligtvis 3-48 timmar) och som förbrukar stora mängder organiska lösningsmedel (upp till 0,5 l per prov). Dessa äldre tekniker där vissa har använts under mer än 100 år, behöver idag ersättas. Dagens... (More)
Popular Abstract in Swedish

För att kunna mäta ett ämnes halt i ett prov behövs en analysmetod. Det första steget i en analysmetod innefattar provupparbetning. Med det menas att ämnet man vill mäta halten av avskiljs (extraheras) från provet med någon sorts extraktionsteknik. I laboratorier världen över görs dagligen många analytiska extraktioner. Det kan handla om t.ex. livsmedelsanalyser, miljöanalyser eller medicinska analyser. I de flesta laboratorier utförs analyserna med extraktionstekniker, som är mycket tidskrävande (vanligtvis 3-48 timmar) och som förbrukar stora mängder organiska lösningsmedel (upp till 0,5 l per prov). Dessa äldre tekniker där vissa har använts under mer än 100 år, behöver idag ersättas. Dagens krav på snabba, pålitliga och selektiva analysmetoder tillsammans med förbud av användning av vissa lösningsmedel, samt kravet på att avfallshantera förbrukade lösningsmedel, har lett till utveckling av moderna extraktionstekniker. Dessa innefattar överkritisk vätskeextraktion (eng. Supercritical fluid extraction), vätskeextraktion med uppvärming med hjälp av mikrovågor (eng. Microwave-assisted extraction) och trycksatt vätskeextraktion (eng. Pressurized liquid extraction). Gemensamt för dessa extraktionstekniker är att de utförs vid förhöjt tryck och temperatur. Detta medför ökad frisättningshastighet av de ämnen man vill mäta och därmed en snabbare extraktion med extraktionstider på mellan 10 minuter och 1 timme. Med dessa nya tekniker kan samtidigt konsumtionen av hälsofarliga, organiska lösningsmedel minskas drastiskt. Det kan räcka med 2-100 ml lösningsmedel per prov. Några av teknikerna är ännu mer miljövänliga där koldioxid eller vatten används som lösningsmedel. I mitt avhandlingsarbete har analysmetoder baserade på en eller flera moderna extraktionstekniker utvecklats för några olika ämnen och prover såsom bestämning av bekämpningsmedel i industriellt damm (artikel I & VII), cancerogena aminer i läder som bildas då azofärger bryts ner (artikel II & VI), alkylfenoler i vattenprover (artikel III), den verksamma substansen i ett läkemedel (artikel IV) och toxin i vete och majs (artikel V). I alla arbeten visas att de moderna extraktionsteknikerna är snabbare, kräver mindre mängder lösningsmedel, samt är lika eller mer effektiva än de traditionella teknikerna. Sammanfattningsvis kan man säga att moderna extraktionstekniker bör användas i framtiden för rutinanalyser. (Less)
Abstract
Today’s requirements of fast, reliable and selective analytical methods with minimal usage of organic solvents have accelerated the development of new, automated extraction techniques. In this thesis recent extraction techniques with emphasis on supercritical fluid extraction (SFE) and microwave-assisted extraction (MAE) were investigated. Different environmental and industrial applications such as extraction of pesticides from process dust, active compounds in pharmaceutical tablets, mycotoxins in cereals and aromatic amines released from azo dyes in leather have been studied to outline advantages and limitations of the techniques. In all cases the extraction efficiencies were similar or better, solvent usage reduced and extraction times... (More)
Today’s requirements of fast, reliable and selective analytical methods with minimal usage of organic solvents have accelerated the development of new, automated extraction techniques. In this thesis recent extraction techniques with emphasis on supercritical fluid extraction (SFE) and microwave-assisted extraction (MAE) were investigated. Different environmental and industrial applications such as extraction of pesticides from process dust, active compounds in pharmaceutical tablets, mycotoxins in cereals and aromatic amines released from azo dyes in leather have been studied to outline advantages and limitations of the techniques. In all cases the extraction efficiencies were similar or better, solvent usage reduced and extraction times shortened compared to traditional extraction techniques such as sonication and liquid-solid extraction (shaking) procedures. Even though recent extraction techniques in most cases are superior to the conventional techniques, they differ in terms of selectivity, simplicity and sample throughput as discussed in this thesis. By utilizing an elongated trap in SFE further selectivity in the collection step was achieved for extractions of aromatic amines and for separation of fat-soluble vitamins from lipids. Devices to perform direct SFE of liquid samples were tested, resulting in a selective extraction of alkylphenols from real waste water samples. Furthermore, a fractionated MAE procedure including a reaction/extraction step was developed for the determination of amines after reductive cleavage of azo dyes in leather. A variant of pressurized liquid extraction (PLE) that utilizes water as extracting media is pressurized hot water extraction (PHWE). This technique was investigated for extraction of pesticides from process dust and obtained results were compared with results obtained using SFE. With better understanding of the characteristics of the recent techniques, conventional techniques can in most cases be replaced. In the future it is anticipated that combinations of different extraction techniques will appear in a single analytical method, where the inherent advantages of each technique are utilized. This was here demonstrated , where leather samples were degreased using SFE and further treated using MAE. (Less)
Please use this url to cite or link to this publication:
author
opponent
  • Dr Chester, Thomas L., The Procter & Gamble Company, Miami Valley Laboratories, Cincinnati, USA
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Analytisk kemi, Analytical chemistry, Pressurized hot water extraction, Pressurized liquid extraction, Microwave-assisted extraction, Recent extraction techniques, Supercritical fluid extraction
pages
196 pages
publisher
Cecilia Sparr Eskilsson, Analytical Chemistry, Lund University
defense location
Hall B at Center for Chemistry and Chemical Engineering, Lund
defense date
2003-05-03 10:15
ISBN
91-628-5626-X
language
English
LU publication?
yes
id
f5edc990-6abd-4cb8-965d-b6397353f691 (old id 465707)
date added to LUP
2007-10-14 14:37:02
date last changed
2016-09-19 08:45:07
@misc{f5edc990-6abd-4cb8-965d-b6397353f691,
  abstract     = {Today’s requirements of fast, reliable and selective analytical methods with minimal usage of organic solvents have accelerated the development of new, automated extraction techniques. In this thesis recent extraction techniques with emphasis on supercritical fluid extraction (SFE) and microwave-assisted extraction (MAE) were investigated. Different environmental and industrial applications such as extraction of pesticides from process dust, active compounds in pharmaceutical tablets, mycotoxins in cereals and aromatic amines released from azo dyes in leather have been studied to outline advantages and limitations of the techniques. In all cases the extraction efficiencies were similar or better, solvent usage reduced and extraction times shortened compared to traditional extraction techniques such as sonication and liquid-solid extraction (shaking) procedures. Even though recent extraction techniques in most cases are superior to the conventional techniques, they differ in terms of selectivity, simplicity and sample throughput as discussed in this thesis. By utilizing an elongated trap in SFE further selectivity in the collection step was achieved for extractions of aromatic amines and for separation of fat-soluble vitamins from lipids. Devices to perform direct SFE of liquid samples were tested, resulting in a selective extraction of alkylphenols from real waste water samples. Furthermore, a fractionated MAE procedure including a reaction/extraction step was developed for the determination of amines after reductive cleavage of azo dyes in leather. A variant of pressurized liquid extraction (PLE) that utilizes water as extracting media is pressurized hot water extraction (PHWE). This technique was investigated for extraction of pesticides from process dust and obtained results were compared with results obtained using SFE. With better understanding of the characteristics of the recent techniques, conventional techniques can in most cases be replaced. In the future it is anticipated that combinations of different extraction techniques will appear in a single analytical method, where the inherent advantages of each technique are utilized. This was here demonstrated , where leather samples were degreased using SFE and further treated using MAE.},
  author       = {Sparr Eskilsson, Cecilia},
  isbn         = {91-628-5626-X},
  keyword      = {Analytisk kemi,Analytical chemistry,Pressurized hot water extraction,Pressurized liquid extraction,Microwave-assisted extraction,Recent extraction techniques,Supercritical fluid extraction},
  language     = {eng},
  pages        = {196},
  publisher    = {ARRAY(0x8882458)},
  title        = {Recent Extraction Techniques with Emphasis on Supercritical Fluid Extraction and Microwave-assisted Extraction},
  year         = {2003},
}