Paderborn, Universiẗat, Diss., 2001.

In dieser Arbeit wurde der Einsatz von Amberlite XAD 7 HP imprägniert mit Di-(2-ethylhexyl)phosphorsäure als Solvent imprägniertes Harz für die Trennung von Ionen Seltener Erdelemente in einer Trennsäule untersucht. Mittels Batchversuchen wurden die Extraktionsisothermen und Extraktionskinetiken für verschiedene Seltene Erdelemente an imprägniertem Amberlite XAD 7 HP bestimmt und der Einfluss der Amberlitepartikelgröße auf diese Isothermen und Kinetiken untersucht. Versuche an der Trennsäule zeigten einen großen Einfluss des Volumenstroms des Elutionsmittels und der Amberlitepartikelgröße auf den Trennerfolg eines binären Gemischs Seltener Erdelemente. Im Gegensatz zu den unzerkleinerten Amberlitepartikeln ist es durch den Einsatz von zerkleinerten Amberlitepartikeln möglich gewesen, ein Cerium-Lanthan-Gemisch zu trennen. Die Regenerationsfähigkeit und die Wiederverwendbarkeit des hergestellten Solvent imprägnierten Harzes konnte gezeigt werden.:Inhaltsverzeichnis 1 Einleitung und Zielstellung .............................................................................. 1 2 Stand von Wissenschaft und Technik ............................................................. 3 2.1 Seltene Erdelemente ................................................................................ 3 2.1.1 Vorkommen und Anwendungsgebiete von Seltenen Erdelementen .. 4 2.1.2 Chemische und physikalische Eigenschaften von Seltenen Erdelementen ..................................................................................... 7 2.1.3 Abbau und Aufbereitung von Seltenen Erdelementen ..................... 10 2.1.4 Verfahren für die Trennung von Gemischen Seltener Erdelemente . 11 2.1.5 Alternative und umweltschonendere Verfahren für die Trennung von Gemischen Seltener Erdelemente ............................................. 18 2.2 Zerkleinern von polymeren Materialien .................................................. 22 2.2.1 Zerkleinerung von Ionentauschern in verschiedenen Mühlen .......... 23 2.2.2 Zerkleinern von polymeren Ionentauscherpartikeln in einer Trommelmühle ................................................................................. 25 2.3 Adsorptionsisotherme/Extraktionsisotherme .......................................... 27 2.4 Einführung in die Extraktionschromatographie ....................................... 31 2.4.1 Grundlagen der Extraktionschromatographie ................................... 32 2.4.2 Solvent imprägnierte Harze und Levextrel-Harze - spezielle Formen von Trägermaterialien ......................................................... 45 2.4.2.1 Herstellung und Eigenschaften von Solvent imprägnierten Harzen ................................................................................. 47 2.4.2.2 Eigenschaften und Herstellung von Levextrel-Harzen .......... 51 2.4.2.3 Einsatz von Solvent imprägnierten Harzen und LevextrelHarzen in der Metallextraktion ............................................. 52 2.4.2.4 Probleme bei dem Einsatz von Solvent imprägnierten Harzen ................................................................................. 56 IV 2.4.3 Einfluss der Struktur des Trägermaterials und der Arbeitsbe- dingungen auf die Trennleistung einer Trennsäule .......................... 57 2.4.4 Einsatz der Extraktionschromatographie für die Trennung von Gemischen Seltener Erdelemente ................................................... 60 2.4.5 Mechanismus bei der Trennung von Seltenen Erdelementen mittels Extraktionschromatographie und D2EHPA ............................ 64 3 Experimentelles Arbeiten .............................................................................. 67 3.1 Verwendetet Materialien ......................................................................... 67 3.1.1 Trägermaterialien ............................................................................. 67 3.1.2 Stationäre Phase.............................................................................. 71 3.1.3 Seltene Erdelemente ........................................................................ 72 3.2 Verwendete Apparaturen und Messgeräte ............................................. 72 3.2.1 Messmethoden für die Partikelcharakterisierung ............................. 72 3.2.2 Bestimmung der Elementkonzentration von wässrigen Proben mittels ICP OES ............................................................................... 75 3.2.3 Aufbau und Funktionsweise der Trennsäule .................................... 79 3.3 Durchführung von Versuchen zur Charakterisierung der Extraktionsmaterialien und zur Trennung binärer Gemische Seltener Erdelemente ..... 82 3.3.1 Waschung von Amberlite XAD 7 HP ................................................ 84 3.3.2 Zerkleinern und Klassieren von Amberlite XAD 7 HP ...................... 84 3.3.3 Imprägnierung von Amberlite XAD 7 HP .......................................... 85 3.3.4 Batchversuche zur Ermittlung geeigneter Parameter, Extraktionskinetiken, Extraktionskapazitäten und Säurekonzentrationen .......... 86 3.3.5 Trennung von Ionen Seltener Erdelemente mittels Trennsäule ....... 89 3.3.6 Prüfung auf Reproduzierbarkeit der Versuche an der Trennsäule ... 93 3.3.7 Prüfung auf Wiederverwendbarkeit des Extraktionsmaterials .......... 93 3.3.8 Hydrophobierung von hydrophilen Oberflächen ............................... 94 4 Ergebnisse .................................................................................................... 96 4.1 Zerkleinerung des Trägermaterials Amberlite XAD 7 HP ....................... 96 V 4.2 Reaktionsmechanismus von Ionen Seltener Erdelemente bei der Extraktion ............................................................................................. 100 4.3 Imprägnierung des Trägermaterials Amberlite XAD 7 HP .................... 101 4.4 Charakterisierung des Trägermaterials Amberlite XAD 7 HP vor und nach der Imprägnierung mit D2EHPA ................................................... 103 4.4.1 Unzerkleinertes Trägermaterial Amberlite XAD 7 HP ..................... 103 4.4.2 Zerkleinertes Trägermaterial Amberlite XAD 7 HP ......................... 107 4.4.3 Auswertung der 3D-Röntgenmikroskopie einer mit Neodym beladenen Amberliteschüttung ........................................................... 110 4.5 Vorversuche zur Ermittlung von geeigneten Versuchsparametern und zur Bestimmung der Kapazitäten des Extraktionsmaterials ........... 112 4.5.1 Ermittlung des optimalen pH-Werts für die Trennung von Ge- mischen Seltener Erdelemente ...................................................... 112 4.5.2 Ermittlung der optimalen Schüttelzeit für maximale Extraktionskapazitäten ..................................................................................... 113 4.5.3 Extraktionskinetik ........................................................................... 115 4.5.4 Ermittlung von Extraktionsisothermen ausgewählter Seltener Erdelemente ................................................................................... 118 4.5.5 Bestimmung der Trennfaktoren von binären Gemischen Seltener Erdelemente mittels imprägniertem Amberlite XAD 7 HP .............. 124 4.5.6 Variation der Stoffmengenkonzentration des Elutionsmittels Salzsäure für die Trennung von Gemischen Seltener Erdelemente ..... 127 4.5.7 Typische Störkomponenten ........................................................... 129 4.6 Charakterisierung der Trennsäule ........................................................ 130 4.6.1 Überprüfung der Reproduzierbarkeit der Ergebnisse ..................... 131 4.6.2 Variation des Volumenstroms der mobilen Phase in der Trennsäule ..................................................................................... 132 4.6.3 Prüfung der Wiederverwendbarkeit des Extraktionsmaterials ........ 137 4.6.4 Lokale Masseverteilung der Seltenen Erdelemente in der Trennsäule ..................................................................................... 140 VI 4.7 Trennung binärer Gemische Seltener Erdelemente mittels unzerkleinertem imprägniertem Amberlite XAD 7 HP ........................... 146 4.8 Trennung binärer Gemische Seltener Erdelemente mittels zer- kleinertem imprägniertem Amberlite XAD 7 HP .................................... 152 4.9 Untersuchung zum Trennverhalten eines Eisen-Lanthan-Gemischs (mögliche Störkomponenten) ............................................................... 159 4.10 Weitere Trägermaterialien .................................................................... 162 4.10.1 Lewatit VP OC 1026 ....................................................................... 162 4.10.2 Celite-512 ....................................................................................... 169 4.10.3 Divergan RS ................................................................................... 171 4.10.4 Vergleich aller eingesetzten Trägermaterialien .............................. 173 5 Zusammenfassung und Ausblick ................................................................ 175 6 Literaturverzeichnis ..................................................................................... 178 Abbildungsverzeichnis .................................................................................... 197 Tabellenverzeichnis ........................................................................................ 208 Anhang ........................................................................................................... 210

ABSTRACT PRECONCENTRATION OF SOME PRECIOUS METALS USING DEBT IMPREGNATED RESIN Refiker, H&uuml / rm&uuml / s M. Sc., Department of Chemistry Supervisor: Prof. Dr. R. Sezer Ayg&uuml / n Co-supervisor: Assoc. Prof. Dr. Melek Merdivan August 2005, 107 pages In this thesis, trace amounts of gold and silver have been determined by flame absorption spectrometry (FAAS) after preconcentration by N,N-diethyl-N&#039 / -benzoylthiourea (DEBT) impregnated resin (Amberlite XAD-16). In the first part of the thesis, sorption behaviours of gold and silver with DEBT impregnated resin under optimized conditions / stirring time, pH, desorption of metals and metal ion capacities of the resin have been studied in batch process. Metal ion capacity of resin is calculated as 0.17 mmol/g resin and 0.104 mmol/g resin for silver and for gold, respectively. In the second part of the thesis, preconcentration of gold and silver was tried by DEBT impregnated resin using column process under optimized conditions / pH, flow rate and volume of sample solution, nature of eluent, flow rate and volume of eluent However, due to partial leaching of DEBT by time, no satisfactory and reproducible results could be obtained. In the final part of the study, metal chelates prepared in aqueous solutions were passed through the column under optimized conditions and satisfactory sorption-desorption and selective preconcentration could be achieved. Under optimized conditions, silver and gold ions at the concentrations of 0.05 &amp / #61549 / g/mL and 0.015 &amp / #61549 / g/mL with preconcentration factors of 7.7 and 6.7, respectively could be determined by FAAS. The proposed method is highly selective without the need for any interference elimination process. Keywords: Precious metals, Solid-phase extraction, DEBT, Amberlite XAD-16

The work has been focused on the preconcentration techniques for determination of 9Be, 51V, 59Co, 60Ni, 89Y, 111Cd, 208Pb, 232Th and 238U on the modified sorbents, all measurements were performed on ICP-MS. The instrument setup was optimized. The solution of internal standard (200 µg•l-1) was used during all measurements. The internal standard were chosen as follows: 6Li for 9Be, 45Sc (51V), 72Ge (59Co, 60Ni, 89Y), 103Rh (111Cd), 209Bi (206Pb, 207Pb, 208Pb, 232Th and 238U). Another parameters such as influence of mineral acids (HCl, HNO3), surfactant (Septonex®, Zephyramin, Ajatin, Brij 35 and Sodium dodecyl sulphate) and organic reagents (Ammonium pyrrolidinedithiocarbamate, 8-Hydroxyquinoline-5-sulphonic acid, 1,2-Dihydroxyanthraquinone-3-sulphonic acid and 4-(2-Pyridylazo)resorcinol) and the effect of some matrix components on intensity of instrument signal determination was investigated. For preconcentration polar Silicagel and modified nonpolar Silicagels (Silicagel-C18, C8 nad Phenyl) were used. Another experimantal part was dedicated to preconcentration on nonpolar Amberlite XAD-16 and Strata SDB-L and intermediately polar sorbent Amberlite XAD-7. Recoveries of sorption process were observed in the presence of all testing types of surfactants in certified concentration 5•10-4 mol•l-1. Surfactants were always applied in the conditioning step. The suitable combinations of surfactant and organic reagent were tested for increasing of recoveries of analytes. Testing organic reagents were added in five times mass excess againts concentration of analytes, the concentration of the organic reagents was 900 µg•l-1. The organic reagent was always added to the solution for preconcentration before this solution was led on the sorbent. The composition and a necessary volume of elution mixture for quantitative elution were tested, too. Only one sorbent was chosen from each group of sorbents with similar properties. The chosen sorbent showed the best recoveries in majority of target analytes. The highest recoveries from silica-group was reached for Silicagel-C18, from nonpolar Amberlite was chosen Strata SDB-L and intermediately polar Amberlite XAD-7. The influence of some matrix components (anionts and cations) on recoveries of analytes was investigated for chosen sorbent. The optimized process was applied on real samples of nature water and industry water. In experimental part all analytes are marked as specific izotopes, which were measured by ICP-MS. Of course, all izotopes of analytes undergo preconcentration techniques.

<p>To improve the adsorption capacity of polyacrylonitrile (PAN) fibres, hydrophilic amidoxime fibres were prepared by subsequent conversion of the cyano groups to an amidoxime group by reacting with hydroxylamine at 80&deg / C at an optimum amidoximation time of 2 hrs. The amidoxime fibre was hydrolyzed/alkali treated in a solution of sodium hydroxide to enhance or improve the adsorption properties. This was followed by characterization of the amidoxime and hydrolyzed fibres using Scanning electron microscopy (SEM) / Fourier transform Infrared Spectroscopy (FTIR) and exchange capacity (cationic and anionic). SEM showed that the hydrolysis process made the surface of Amidoxime fibre rougher than that of Polyacrylonitrile fibre. FTIR revealed that the hydrolyzed Amidoxime fibres contained conjugated imine (-C=N-) sequences. Functionalization enhanced the sorption of amidoxime fibres by an increase of 20 % in the cationic exchange capacity. This was achieved by the part conversion of the cyano groups into the carboxylic acid groups. The fibres showed faster kinetics largely due the available exchange sites on the surface of the fibres hence the equilibration was achieved much quicker.</p>

<p>To improve the adsorption capacity of polyacrylonitrile (PAN) fibres, hydrophilic amidoxime fibres were prepared by subsequent conversion of the cyano groups to an amidoxime group by reacting with hydroxylamine at 80&deg / C at an optimum amidoximation time of 2 hrs. The amidoxime fibre was hydrolyzed/alkali treated in a solution of sodium hydroxide to enhance or improve the adsorption properties. This was followed by characterization of the amidoxime and hydrolyzed fibres using Scanning electron microscopy (SEM) / Fourier transform Infrared Spectroscopy (FTIR) and exchange capacity (cationic and anionic). SEM showed that the hydrolysis process made the surface of Amidoxime fibre rougher than that of Polyacrylonitrile fibre. FTIR revealed that the hydrolyzed Amidoxime fibres contained conjugated imine (-C=N-) sequences. Functionalization enhanced the sorption of amidoxime fibres by an increase of 20 % in the cationic exchange capacity. This was achieved by the part conversion of the cyano groups into the carboxylic acid groups. The fibres showed faster kinetics largely due the available exchange sites on the surface of the fibres hence the equilibration was achieved much quicker.</p>

Natural plant growth regulators (phytohormones) are a group of organic compounds which, in very small amounts, act as regulators of physiological processes in plants.Methods were developed for the analysis of phytohormones in samples from Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris (L.) Karst»). Identification of abscisic acid, 3-indoleacetic acid, gibbe-rellin Ag and the conjugate N-(3-indoleacetyl)aspartic acid was performed by GC-MS as their methyl esters. A quantitative determination of abscisic acid was made by GC-ECD and this method was also applied to anther samples of Anemone canadensis. 3-Indole-acetic acid and N-(3-indoleacetyl)aspartic acid were quantified by reversed-phase HPLC and spectrofluorimetric detection. Dichlorophene, used as a growth regulator in containerized seedlings of pine and spruce, was analysed by GC-MID in peat and paper. / digitalisering@umu

Magister Scientiae - MSc / To improve the adsorption capacity of polyacrylonitrile (PAN) fibres, hydrophilic amidoxime fibres were prepared by subsequent conversion of the cyano groups to an amidoxime group by reacting with hydroxylamine at 80°C at an optimum amidoximation time of 2 hrs. The amidoxime fibre was hydrolyzed/alkali treated in a solution of sodium hydroxide to enhance or improve the adsorption properties. This was followed by characterization of the amidoxime and hydrolyzed fibres using Scanning electron microscopy (SEM); Fourier transform Infrared Spectroscopy (FTIR) and exchange capacity (cationic and anionic). SEM showed that the hydrolysis process made the surface of Amidoxime fibre rougher than that of Polyacrylonitrile fibre. FTIR revealed that the hydrolyzed Amidoxime fibres contained conjugated imine (-C=N-) sequences. Functionalization enhanced the sorption of amidoxime fibres by an increase of 20 % in the cationic exchange capacity. This was achieved by the part conversion of the cyano groups into the carboxylic acid groups. The fibres showed faster kinetics largely due the available exchange sites on the surface of the fibres hence the equilibration was achieved much quicker. / South Africa

M.Tech. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology. / In the present study, the removal of Ca2+ and Mg2+ from cooling tower water using Amberlite IR120 and Amberjet 1200 was studied by the application of one factor at a time method (OFAT) and response surface modelling (RSM). The effect of operational parameters such as contact time (min), pH, dosage (mL), concentration (mg/L) and temperature (K) were investigated using central composite design. The regeneration of the Amberlite IR120 and Amberjet were also studied. The purpose of the study was to apply OFAT and RSM to investigate and optimize the ion exchange operating parameters. Furthermore, the second-order empirical model that was developed, using the analysis of variance (ANOVA), presented a sufficient correlation to the ion exchange experimental data. The optimal ion exchange operating conditions for Amberlite IR120 and Amberjet 1200 were found to be: contact time was 120 min, dosage of 150mL, initial pH level of 2, concentration of 400mg/L and temperature of 343K. Regeneration of Amberlite IR120 and Amberjet 1200 using 0.5 M NaCl stripping solution initially showed an increase in % Ca2+ and Mg2+ removal, then a decrease in subsequent cycles. The correlation coefficients (R2) of Langmuir, Freudlich and Tempkin isotherms were found to range from 0.92 to 1 and this suggest that experimental data best described the models. However correlation coefficients (R2) for Dubinin–Radushkevich (D-R) model were found to range between 0.5 to 0.8 and this means that experimental data does not fit the model. Thermodynamic functions such as entropy (Δ𝑆𝑜), enthalpy (Δ𝐻𝑜) and change of free energy (Δ𝐺𝑜) were obtained from the gradient and intercepts of straight line graphs. The positive values of ΔG° were found meaning that the adsorption is not spontaneous and positive values of ΔH° were found meaning the endothermic type of adsorption which indicate the chances of physical adsorption.The correlation coefficient (R2) values of pseudo-first-order, pseudo-second-order and intraparticle models were found to range from 0.89 to 1 on both metals as shown in table 4.4. This observation clearly indicates that pseudo-first-order, pseudo-second-order and intraparticle diffusion models best describe the experimental data in the removal Ca2+ and Mg2+ from cooling tower water.

The aim of this thesis was to introduce and apply the possibilities of using waste glycerol from biodiesel production and partly waste low-stiffen coolant from cars that could be applied in industry. At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. There are described the ion exchange mechanism, ion exchange resin properties and the properties of the acids and salts generated by neutralization with NaOH contained in the waste glycerol. Also is described herein the wood protection and properties of ethylene glycol coolants and properties of boroglycerol and boroglycol as protection for wood and mechanism of their preparation. Next is described the mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured, then was measured the exact amount of NaOH in the glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol.