Technische Universität Bergakademie Freiberg: Qucosa
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Modulation of growth and gene transcription of metabolic routes for nitrogen and phytohormones in Polypogon australis plants, mediated by the supernatant of a cyanobacterial culture
Get PDFÜberstände von Cyanobakterien sind ein vielversprechendes Produkt zur Förderung des Pflanzenwachstums, da sie alle Vorteile der freigesetzten bioaktiven Verbindungen, wie z. B. Phytohormone, enthalten, ohne die Zwänge der mikrobiellen Inokulationen. Es ist jedoch nur wenig darüber bekannt, wie Cyanobakterien die Reaktion der Pflanzen auf molekularer Ebene modulieren könnten.
In dieser Studie wurde das in Chile heimische Gras Polypogon australis als Modell verwendet, um die Wirkung von Überständen aus Kulturen von sieben autochthonen Bodencyanobakterien zu untersuchen. Von diesen zeigten die Überstände der Kulturen von Trichormus sp. die beste wachstumsfördernde Wirkung auf P. australis. Die ICP-MS-Analyse ergab, dass die Überstände von Trichormus sp. eine ähnliche Nährstoffzusammensetzung aufwiesen wie das für das Wachstum der Cyanobakterien verwendete Medium BG-11, mit Ausnahme der Elemente P und Mn, die in der späten exponentiellen Phase der Kulturen verarmt waren. Dann wurden Überstände von Trichormus sp.-Kulturen, die in der späten exponentiellen Phase gesammelt wurden und die eine Menge von 32,7 pmol trans-Zeatin pro mg Chl-a enthielten, zur Bewertung der Reaktion von P. australis auf transkriptioneller Ebene verwendet. Ein BG-11-Medium, das frei von P und Mn war, wurde als Kontrolle verwendet. Ganzes Pflanzengewebe wurde 3 Stunden nach der Behandlung entnommen und für eine RNA-seq-Analyse verwendet. Die Ergebnisse zeigten, dass die Überstände von Trichormus sp. die Pflanzenreaktion hauptsächlich über die N- und Phytohormonwege modulierten, die in engem Zusammenhang mit dem C- und Lipidstoffwechsel stehen. Die behandelten Pflanzen wiesen 4 und 8 Tage nach der Anwendung größere Triebe auf als die Kontrollpflanzen, aber es wurden keine Unterschiede bei der Wurzellänge festgestellt. Dieser Phänotyp lässt sich durch die Induktion von Genen für die Gibberellin-Biosynthese in P. australis erklären, die durch andere Hormone wie Auxine, Brassinosteroide und Ethylen unterstützt wird. Andererseits wurde in mit P. australis behandelten Pflanzen eine induzierte systemische Resistenzreaktion beobachtet, die hauptsächlich durch einen Ethylen-Jasmonat-Crosstalk vermittelt wurde. Diese Arbeit unterstützt die Verwendung von Überständen als eine gute Option zur Förderung des Pflanzenwachstums.:Table of content
Preliminary Page
Resumen i
Abstract ii
Übersetzung iii
DECLARATION ix
1. Introduction 1
1.1. Plant-growth promoting microorganisms 1
1.2. Soil cyanobacteria 2
1.3. Physiology of soil cyanobacteria 2
1.4. Cyanobacterial plant growth-promoting molecules 4
1.5. Plant response to bioactive compounds 6
1.6. Cyanobacterial supernatants 9
1.7. Polypogon australis as a plant study model 11
2. Methodology 13
2.1. Obtention of the cyanobacterial cultures 13
2.2. Supernatant collection from the cyanobacterial cultures 14
2.3. Cyanobacterial biomass quantification 15
2.3.1. Chlorophyll-a content 15
2.3.2. Biomass dry weight 15
2.3.3. Determination of the growth phases 15
2.4. Chemical characterization of the supernatants 16
2.4.1. Nitrate content 16
2.4.2. Total element content 16
2.4.3. Zeatin content 16
2.5. Preparation of the modified BG-11 medium (BG-11M medium) 17
2.6. Bioassays with cyanobacterial supernatants 18
2.6.1. Effect of supernatants of the 25 mL cultures on P. australis germination 18
2.6.2. Effect of supernatants of the 25 mL cultures on P. australis plants 18
2.6.3. Effect of supernatants of the 2,400 mL cultures on P. australis plants 19
2.7. Statistical analysis 19
2.8. Determination of transcriptional changes in P. australis. 20
2.8.1. Plant treatments and tissue collection 20
2.8.2. Total RNA extraction from plant tissue 20
2.8.3. DNA removal 20
2.8.4. mRNA sequencing, de novo assembly, and differential expression analysis 21
2.8.5. Contig annotation and functional classification 22
3. Results 24
3.1. Trichormus sp. cultures produce the highest biomass content 24
3.2. Trichormus sp. cultures have a low P content 25
3.3. Trichormus sp. supernatants have the best growth-promoting effect on the growth of P. australis 25
3.4. Supernatant nutrient content of Trichormus sp. cultures change through the growth phases 27
3.5. Supernatants used in the transcriptomic assay and BG-11M medium have a lower nutrient content than BG-11 medium 30
3.6. Trichormus sp. supernatants promote the growth of P. australis to a greater extent than the BG-11M medium 32
3.7. Trichormus sp. supernatants contain zeatin 33
3.8. Trichormus sp. supernatants modulated more P. australis genes than the BG-11M medium 34
3.9. Trichormus sp. supernatants regulate the gene expression of growth and defense responses in P. australis 37
4. Discussion 57
4.1. The plant-growth promoting effect of Thrichormus sp. supernatants 57
4.2. The role of P and Mn in the growth-promoting effect of Trichormus sp. supernatants 58
4.3. Modulation of P. australis N-metabolism by Trichormus sp. supernatants 59
4.4. P. australis nitrogen and carbon metabolism in response to Trichormus supernatants 63
4.5. P. australis phytohormone-metabolism modulated by Trichormus supernatants 64
4.6. The role of lipid metabolism in the response to Trichormus supernatants 67
4.7. P. australis defense response triggered by Trichormus supernatants 68
4.8. Phytohormone crosstalk and defense response in P. australis treated with Trichormus sp. supernatants 71
4.9. Perspectives and challenges for the biotechnological use of Trichormus sp. supernatants 73
5. Conclusion 76
Bibliographic references 77
Annexes 116Cyanobacterial supernatants are a promising plant growth-promoting product since they contain all the advantages of the released bioactive compounds, such as phytohormones, without the constraints of microbial inoculations. However, little is known about how cyanobacteria could modulate the plant response at a molecular level.
In this research, the Chilean native grass, Polypogon australis, was used as a model for assaying the effect of supernatants obtained from cultures of seven autochthonous soil cyanobacteria. Of them, supernatants of Trichormus sp. cultures showed the best growth-promoting effects on P. australis. Analysis by ICP-MS showed that Trichormus sp. supernatants had a similar nutrient composition to the medium used for the cyanobacteria growth, BG-11, except for the elements P and Mn, which were depleted when the late exponential phase of the cultures was reached. Then, supernatants of Trichormus sp. cultures collected in the late exponential phase, which contained an amount of 32.7 pmol of trans-zeatin per mg of Chl-a, were employed for evaluating the P. australis response at a transcriptional level. A BG-11 medium free of P and Mn was utilized as a control. Whole plant tissue was collected 3 h-post treatment and used for an RNA-seq analysis. Results showed that Trichormus sp. supernatants modulated the plant response mainly by the N and phytohormones pathways, in close relation with C and lipid metabolism. Treated plants showed larger shoots than control plants 4 and 8 days after application, but no differences were observed in root length. This phenotype can be explained by the induction in P. australis of gibberellin biosynthesis genes, supported by other hormones such as auxins, brassinosteroids, and ethylene. On the other hand, an induced systemic resistance response was observed in P. australis-treated plants, mostly mediated by an ethylene-jasmonate crosstalk. This work supports the use of supernatants as a good plant growth-promoting option.:Table of content
Preliminary Page
Resumen i
Abstract ii
Übersetzung iii
DECLARATION ix
1. Introduction 1
1.1. Plant-growth promoting microorganisms 1
1.2. Soil cyanobacteria 2
1.3. Physiology of soil cyanobacteria 2
1.4. Cyanobacterial plant growth-promoting molecules 4
1.5. Plant response to bioactive compounds 6
1.6. Cyanobacterial supernatants 9
1.7. Polypogon australis as a plant study model 11
2. Methodology 13
2.1. Obtention of the cyanobacterial cultures 13
2.2. Supernatant collection from the cyanobacterial cultures 14
2.3. Cyanobacterial biomass quantification 15
2.3.1. Chlorophyll-a content 15
2.3.2. Biomass dry weight 15
2.3.3. Determination of the growth phases 15
2.4. Chemical characterization of the supernatants 16
2.4.1. Nitrate content 16
2.4.2. Total element content 16
2.4.3. Zeatin content 16
2.5. Preparation of the modified BG-11 medium (BG-11M medium) 17
2.6. Bioassays with cyanobacterial supernatants 18
2.6.1. Effect of supernatants of the 25 mL cultures on P. australis germination 18
2.6.2. Effect of supernatants of the 25 mL cultures on P. australis plants 18
2.6.3. Effect of supernatants of the 2,400 mL cultures on P. australis plants 19
2.7. Statistical analysis 19
2.8. Determination of transcriptional changes in P. australis. 20
2.8.1. Plant treatments and tissue collection 20
2.8.2. Total RNA extraction from plant tissue 20
2.8.3. DNA removal 20
2.8.4. mRNA sequencing, de novo assembly, and differential expression analysis 21
2.8.5. Contig annotation and functional classification 22
3. Results 24
3.1. Trichormus sp. cultures produce the highest biomass content 24
3.2. Trichormus sp. cultures have a low P content 25
3.3. Trichormus sp. supernatants have the best growth-promoting effect on the growth of P. australis 25
3.4. Supernatant nutrient content of Trichormus sp. cultures change through the growth phases 27
3.5. Supernatants used in the transcriptomic assay and BG-11M medium have a lower nutrient content than BG-11 medium 30
3.6. Trichormus sp. supernatants promote the growth of P. australis to a greater extent than the BG-11M medium 32
3.7. Trichormus sp. supernatants contain zeatin 33
3.8. Trichormus sp. supernatants modulated more P. australis genes than the BG-11M medium 34
3.9. Trichormus sp. supernatants regulate the gene expression of growth and defense responses in P. australis 37
4. Discussion 57
4.1. The plant-growth promoting effect of Thrichormus sp. supernatants 57
4.2. The role of P and Mn in the growth-promoting effect of Trichormus sp. supernatants 58
4.3. Modulation of P. australis N-metabolism by Trichormus sp. supernatants 59
4.4. P. australis nitrogen and carbon metabolism in response to Trichormus supernatants 63
4.5. P. australis phytohormone-metabolism modulated by Trichormus supernatants 64
4.6. The role of lipid metabolism in the response to Trichormus supernatants 67
4.7. P. australis defense response triggered by Trichormus supernatants 68
4.8. Phytohormone crosstalk and defense response in P. australis treated with Trichormus sp. supernatants 71
4.9. Perspectives and challenges for the biotechnological use of Trichormus sp. supernatants 73
5. Conclusion 76
Bibliographic references 77
Annexes 116Los sobrenadantes de cianobacterias son prometedores productos promotores del crecimiento vegetal, pues contienen todas las ventajas de los compuestos bioactivos liberados, como fitohormonas, sin las limitaciones de las inoculaciones microbianas. Lamentablemente, poco se sabe sobre cómo las cianobacterias modularían la respuesta de las plantas a nivel molecular.
En esta investigación, se utilizó la gramínea nativa chilena Polypogon australis como modelo para evaluar el efecto de sobrenadantes de cultivos de siete cianobacterias autóctonas de suelo. Los sobrenadantes de Trichormus sp. mostraron mejores efectos promotores del crecimiento de P. australis. Análisis mediante ICP-MS evidenciaron que estos sobrenadantes tenían un contenido nutricional similar al medio de crecimiento de las cianobacterias, BG-11, excepto por los elementos P y Mn, que se agotaron al alcanzarse la fase exponencial tardía de los cultivos. Para evaluar la respuesta de P. australis a nivel transcripcional, se emplearon sobrenadantes colectados en fase exponencial tardía de cultivos de Trichormus sp., que contenían una cantidad de 32,7 pmol de trans-zeatina por mg de Chl-a. Un medio BG-11 libre de P y Mn se utilizó como control. Tres horas después del tratamiento se recogió tejido de plantas completas y se le hizo un análisis de RNA-seq. Como resultado, los sobrenadantes principalmente modularon las vías de N y fitohormonas de la planta, en estrecha relación con los metabolismos de C y lípidos. Las plantas tratadas mostraron brotes más grandes que las plantas control, 4 y 8 días después de la aplicación, pero no se observaron diferencias en la longitud radicular. Este fenotipo puede explicarse por la inducción de biosíntesis de giberelina, apoyada por otras hormonas como auxinas, brasinoesteroides y etileno. Además, se observó una inducción de resistencia sistémica en las plantas tratadas, mediada por una interacción etileno-jasmonatos. Este trabajo corrobora el uso de sobrenadantes como una buena opción para promover el crecimiento de las plantas.:Table of content
Preliminary Page
Resumen i
Abstract ii
Übersetzung iii
DECLARATION ix
1. Introduction 1
1.1. Plant-growth promoting microorganisms 1
1.2. Soil cyanobacteria 2
1.3. Physiology of soil cyanobacteria 2
1.4. Cyanobacterial plant growth-promoting molecules 4
1.5. Plant response to bioactive compounds 6
1.6. Cyanobacterial supernatants 9
1.7. Polypogon australis as a plant study model 11
2. Methodology 13
2.1. Obtention of the cyanobacterial cultures 13
2.2. Supernatant collection from the cyanobacterial cultures 14
2.3. Cyanobacterial biomass quantification 15
2.3.1. Chlorophyll-a content 15
2.3.2. Biomass dry weight 15
2.3.3. Determination of the growth phases 15
2.4. Chemical characterization of the supernatants 16
2.4.1. Nitrate content 16
2.4.2. Total element content 16
2.4.3. Zeatin content 16
2.5. Preparation of the modified BG-11 medium (BG-11M medium) 17
2.6. Bioassays with cyanobacterial supernatants 18
2.6.1. Effect of supernatants of the 25 mL cultures on P. australis germination 18
2.6.2. Effect of supernatants of the 25 mL cultures on P. australis plants 18
2.6.3. Effect of supernatants of the 2,400 mL cultures on P. australis plants 19
2.7. Statistical analysis 19
2.8. Determination of transcriptional changes in P. australis. 20
2.8.1. Plant treatments and tissue collection 20
2.8.2. Total RNA extraction from plant tissue 20
2.8.3. DNA removal 20
2.8.4. mRNA sequencing, de novo assembly, and differential expression analysis 21
2.8.5. Contig annotation and functional classification 22
3. Results 24
3.1. Trichormus sp. cultures produce the highest biomass content 24
3.2. Trichormus sp. cultures have a low P content 25
3.3. Trichormus sp. supernatants have the best growth-promoting effect on the growth of P. australis 25
3.4. Supernatant nutrient content of Trichormus sp. cultures change through the growth phases 27
3.5. Supernatants used in the transcriptomic assay and BG-11M medium have a lower nutrient content than BG-11 medium 30
3.6. Trichormus sp. supernatants promote the growth of P. australis to a greater extent than the BG-11M medium 32
3.7. Trichormus sp. supernatants contain zeatin 33
3.8. Trichormus sp. supernatants modulated more P. australis genes than the BG-11M medium 34
3.9. Trichormus sp. supernatants regulate the gene expression of growth and defense responses in P. australis 37
4. Discussion 57
4.1. The plant-growth promoting effect of Thrichormus sp. supernatants 57
4.2. The role of P and Mn in the growth-promoting effect of Trichormus sp. supernatants 58
4.3. Modulation of P. australis N-metabolism by Trichormus sp. supernatants 59
4.4. P. australis nitrogen and carbon metabolism in response to Trichormus supernatants 63
4.5. P. australis phytohormone-metabolism modulated by Trichormus supernatants 64
4.6. The role of lipid metabolism in the response to Trichormus supernatants 67
4.7. P. australis defense response triggered by Trichormus supernatants 68
4.8. Phytohormone crosstalk and defense response in P. australis treated with Trichormus sp. supernatants 71
4.9. Perspectives and challenges for the biotechnological use of Trichormus sp. supernatants 73
5. Conclusion 76
Bibliographic references 77
Annexes 11
Binding modes of methyl α-d-glucopyranoside to an artificial receptor in crystalline complexes
Get PDFCompared to the numerous X-ray crystal structures of protein-carbohydrate complexes, the successful elucidation of the crystal structures of complexes between artificial receptors and carbohydrates has been very rarely reported in the literature. In this work, we describe the binding modes of two complexes formed between methyl α-D-glucopyranoside and an artificial receptor belonging to the class of compounds consisting of a 1,3,5-trisubstituted 2,4,6-trialkylbenzene scaffold. It is particularly noteworthy that these two complexes are present in one crystal structure, as was observed by us for the first time in the case of the recently reported three crystal structures of the complexes with methyl β-D-glucopyranoside, each containing two different receptor–carbohydrate complexes. The noncovalent interactions stabilizing the new complexes are compared with those observed in the aforementioned crystalline complexes with methyl β-D-glucopyranoside
Phase Stability of Iron Nitride Fe4N at High Pressure—Pressure-Dependent Evolution of Phase Equilibria in the Fe–N System
Get PDFAlthough the general instability of the iron nitride γ′-Fe4N with respect to other phases at high pressure is well established, the actual type of phase transitions and equilibrium conditions of their occurrence are, as of yet, poorly investigated. In the present study, samples of γ′-Fe4N and mixtures of α Fe and γ′-Fe4N powders have been heat-treated at temperatures between 250 and 1000 °C and pressures between 2 and 8 GPa in a multi-anvil press, in order to investigate phase equilibria involving the γ′ phase. Samples heat-treated at high-pressure conditions, were quenched, subsequently decompressed, and then analysed ex situ. Microstructure analysis is used to derive implications on the phase transformations during the heat treatments. Further, it is confirmed that the Fe–N phases in the target composition range are quenchable. Thus, phase proportions and chemical composition of the phases, determined from ex situ X-ray diffraction data, allowed conclusions about the phase equilibria at high-pressure conditions. Further, evidence for the low-temperature eutectoid decomposition γ′→α+ε′ is presented for the first time. From the observed equilibria, a P–T projection of the univariant equilibria in the Fe-rich portion of the Fe–N system is derived, which features a quadruple point at 5 GPa and 375 °C, above which γ′-Fe4N is thermodynamically unstable. The experimental work is supplemented by ab initio calculations in order to discuss the relative phase stability and energy landscape in the Fe–N system, from the ground state to conditions accessible in the multi-anvil experiments. It is concluded that γ′-Fe4N, which is unstable with respect to other phases at 0 K (at any pressure), has to be entropically stabilised in order to occur as stable phase in the system. In view of the frequently reported metastable retention of the γ′ phase during room temperature compression experiments, energetic and kinetic aspects of the polymorphic transition γ′⇌ε′ are discussed
Untersuchungen zur CO2-Insertion in Al-N-Bindungen
Get PDFIn dieser Arbeit wurden Tris(N,N-dialkylamido)alane (TDAs) synthetisiert und strukturell aufgeklärt. Durch die Verwendung eines festen Monoalan-Etherats (AlH3 · 1/5 DEE (s)) als Zwischenprodukt ist es möglich, alle TDA-Derivate unabhängig von dem sterischen Anspruch der Amidliganden aus Lithiumaluminiumhydrid herzustellen. Die vorhandenen Al–N-Bindungen wurden im Hinblick auf ihre Reaktivität gegenüber CO2 untersucht. Mittels Insertionsreaktionen wurden aus den TDAs Aluminium-tris(N,N-dialkylcarbamat)-Verbindungen (ADCs) synthetisiert. Die gezielte Hydrolyse der ADCs ergab strukturell einzigartige N,N-dialkylcarbamatverbrückte {Al3(μ3-O)}7+-Komplexverbindungen. Es zeigte sich, dass die an der zentralen Substruktur koordinierenden Neutralliganden gegen andere Lewisbasen austauschbar sind. Darauf aufbauend wurde versucht, durch den Umsatz mit zweizähnigen Linkermolekülen ein Koordinationsnetzwerk zu bilden. Die Charakterisierung des polymeren Reaktionsproduktes ergab jedoch wesentliche Abweichungen von der angestrebten Struktur.:1. Einleitung
2. Tris(N,N-dialkylamido)alane
2.1. Grundlagen und Literaturübersicht
2.2. Ergebnisse und Diskussion
2.2.1. Verwendung einer alternativen Monoalanspezies für die Synthese von TDAs
2.2.2. Klärung der widersprüchlichen Daten von Tris(dimethylamido)alan (TDA3)
2.2.3. Tris(N-methylpiperazino)alan (TDA6) als neuer Vertreter der TDAs
2.2.4. Temperaturabhängige NMR-Untersuchungen der Verbindungen TDA3 und TDA6
2.2.5. Vergleich der synthetisierten TDAs mit der allgemeinen Formel [Al(NR2)3]n (n = 1, 2)
2.2.6. Zusammenfassung
3. Aluminium-tris(N,N-dialkylcarbamat)-Verbindungen
3.1. Grundlagen und Literaturübersicht
3.2. Ergebnisse und Diskussion
3.2.1. Synthese von ADCs mittels CO2-Insertion
3.2.2. Mechanistische Untersuchungen mittels in situ IR-Spektroskopie
3.2.3. Kristallstruktur der Verbindung ADC4a
3.2.4. Zusammenfassung
4. N,N-Dialkylcarbamatverbrückte {Al3(μ3-O)}7+-Komplexverbindungen
4.1. Grundlagen und Literaturübersicht
4.2. Ergebnisse und Diskussion
4.2.1. Erste Daten von {Al3(μ3-O)}7+-Komplexen
4.2.2. Kristallstrukturen der Verbindungen AO1 und AO2
4.2.3. Weitere Informationen bezüglich {Al3(μ3-O)}7+-Komplexen mittels 2DNMR-Untersuchungen
4.2.4. Experimente zum Austausch der gebundenen Neutralliganden
4.2.5. Zusammenfassung
5. Aluminiumorganische Gerüstverbindungen
5.1. Grundlagen und Literaturübersicht
5.2. Ergebnisse und Diskussion
5.2.1. Ligandenaustauschexperimente und Charakterisierung des Produktes
5.2.2. Elementare Zusammensetzung und thermische Zersetzung der Verbindung AO1a
5.2.3. Ergebnisse der 17O-Markierungen der Verbindungen AO1 und AO1a
5.2.4. Porosität und spezifische Oberfläche der Verbindung AO1a
5.2.5. Zusammenfassung
6. Zusammenfassung und Ausblick
Anhang
I. Chemikalien
II. Software
III. Analysemethoden
IV. Versuchsvorschriften
V. Wissenschaftliche Veröffentlichungen
VI. Erlaubnisse zur Nutzung von publiziertem Material
VII.Verzeichnisse
Abkürzungsverzeichnis
Formelzeichen
Literaturverzeichnis
Abbildungsverzeichnis
Tabellenverzeichni
Modellgestützte Optimierung von Hochtemperatur-Konversionsprozessen: Potenziale und Einsatzgrenzen
Get PDFHochtemperatur-Konversionsprozesse sind ein wesentlicher Bestandteil von industriellen Produktionsprozessen, die maßgeblich den Prozesswirkungsgrad und die Produktionskosten beeinflussen. Die modellgestützte Optimierung ermöglicht eine gezielte Verbesserung verschiedener Parameter unter Berücksichtigung von prozesstechnischen, ökonomischen und ökologischen Aspekten. Bisher existiert in der Literatur kein Vergleich der Einsatzmöglichkeiten verschiedener Modellierungsmethoden zur modellgestützten, multikriteriellen Optimierung von Hochtemperatur-Konversionsprozessen. Daher werden in dieser Arbeit drei exemplarische Konversionsprozesse mit unterschiedlichen Modellierungsmethoden optimiert und anhand der Ergebnisse die Potenziale und Einsatzgrenzen für die modellgestützte Optimierung bewertet. Die Modellierung eines Wirbelschichtvergasers zeigt, dass detaillierte CFD-Modelle für komplexe mehrphasige Prozesse zu rechenaufwändig sind. Hingegen ist für einfache einphasige Prozesse wie ein Quench-Reaktor die Optimierung mit reduzierten CFD-Modellen realisierbar. Die Integration von Ersatzmodellen beschleunigt das Optimierungskonzept bei gleicher Ergebnisqualität, was die Optimierung von komplexen Prozessen für einfache Optimierungsprobleme ermöglicht. Die Optimierung der Partialoxidation von flüssigen Einsatzstoffen zur Methanolproduktion zeigt, dass sich Fließbildmodelle gut zur Optimierung von vollständigen Produktionsprozessen und komplexen Optimierungsproblemen eignen. Die Ergebnisse dieser Arbeit können als Basis für die Erstellung von Modellierungs- und Optimierungskonzepten für weitere Hochtemperatur-Konversionsprozesse genutzt werden
Life cycle assessment of feedstock recycling processes
Get PDFThis study examines the ecological impact of exemplary processes for the feedstock recycling of waste fractions. It is shown that the material process efficiency of gasification and pyrolysis has a low impact on the greenhouse gas balance in the short term, but that high product yields are necessary in the long term to avoid an increasing climate impact. In a systemic context, different process routes of syngas and pyrolysis oil utilization are compared, and their efficiency and quantitative potential for greenhouse gas reduction compared to electricity-based alternatives of process direct heating of conventional processes and electrolysis-based process chains are classified. It is shown that direct utilization options with few process steps are ecologically more efficient. Feedstock recycling shows a similar reduction potential to direct heating, while the use of electrolysis-based process chains is inefficient but necessary to achieve systemic climate neutrality.:1. Introduction and outline 1
2. Life cycle assessment methodology 5
2.1. Previous LCA investigation on feedstock recycling 7
2.2. Assessment scope 9
2.3. Attributional vs. consequential LCI modelling 11
2.4. Inventory modelling consistency 12
2.5. Prospective technology assessment 13
2.6. Conclusions for the applied methodology 14
3. Process description and modelling 16
3.1. Feedstock recycling technologies 18
3.1.1. Gasification 18
3.1.2. Syngas conditioning and purification 23
3.1.3. Pyrolysis 29
3.1.4. Pyrolysis oil hydroprocessing 32
3.2. Chemical production technologies 34
3.2.1. Steam cracking 35
3.2.2. Catalytic reforming 37
3.2.3. Olefin and BTX recovery 38
3.2.4. Conventional syngas production 41
3.2.5. Methanol and methanol-based synthesis 43
3.2.6. Ammonia synthesis 48
3.3. Electric power integration options 49
3.4. Conventional waste treatment processes 53
3.4.1. Mechanical biological treatment and material recovery 54
3.4.2. Waste incineration 57
3.5. Utility processes and process chain balancing 59
3.6. Electricity and heat supply modelling 65
4. Individual assessment of feedstock recycling processes 68
4.1. Goal and scope definition 68
4.2. Life cycle inventory 68
4.3. Impact assessment 72
4.4. Interpretation 80
5. System-based assessment of feedstock recycling processes 82
5.1. Goal and scope definition 82
5.2. Life cycle inventory 86
5.2.1. Utility, background system inventory and system integration 88
5.2.2. Assessment scenario definition and parameter variation 90
5.3. Impact assessment 93
5.3.1. Framework Status Quo (FSQ) 93
5.3.2. Framework Energy Integration (FEI) 99
5.4. Interpretation 106
6. Summary and conclusion 109
6.1. Results 110
6.2. Recommendations and outlook 111
References 113
Supplementary Material 13
Open Access – Publikationsunterstützung an der TUBAF
Get PDFIn diesem Beitrag stellen wir die aktuellen Möglichkeiten der Open-Access-Publikationsunterstützung für Angehörige der TU Bergakademie Freiberg (TUBAF) vor und präsentieren eine Statistik zum Open-Access-Publizieren an der TUBAF für die Jahre 2014-2023
Reciprocal influence between MgO-C refractory materials with different MgO grade and a steel melt and the resulting effect on non-metallic inclusions
Get PDFThe thesis addressed the effect of a varying MgO grade in MgO-C refractories on both their behavior in contact with a steel melt and the resulting effect on the non-metallic inclusion (NMI) population in the solidified steel. For this purpose, immersion tests were conducted in a semi-industrial steel casting simulator. In addition, the effect of the steel melting process parameters on the NMI population was thoroughly investigated, providing a guideline for the result interpretation for future experiments in the steel casting simulator. Here, a fundamental concept of data evaluation for the NMI characterization in a steel matrix using automated feature analysis was developed. The main NMI types detected in the solidified steel samples were alumina and MnSi-based inclusions. Their number density depended on the steel melt's temperature and amount of dissolved oxygen. A lower MgO grade refractory specimen in contact with the steel melt resulted in a higher proportion of low melting phases on its surface compared to a higher MgO grade specimen. These low-melting phases promoted the formation of MnSi-based inclusions and triggered NMI agglomeration leading to the formation of large alumina inclusions
Application of X-ray Diffraction (XRD) and Rock–Eval Analysis for the Evaluation of Middle Eastern Petroleum Source Rock
Get PDFIn this study, collected samples of nine different wells from the Middle East are used for various geochemical analyses to determine the hydrocarbon generation potential. The determination is carried out following the grain density, specific surface area, XRD, and Rock–Eval pyrolysis analyses. Four different types of kerogen are plotted based on the Rock–Eval analysis result. Kerogen type I usually has high hydrogen index (e.g., HI > 700) and low oxygen index, which is considered oil-bearing. Kerogen Type II has hydrogen index between type I and type II and oxygen index higher than type I (e.g., 350 < HI < 700) and is also considered to have oil-bearing potential. Kerogen type III has a lower hydrogen index (e.g., HI < 350) and is considered to have a primarily gas-generating potential with terrigenous organic matter origination. Kerogen type IV has a very low hydrogen index and higher oxygen index (compared with other types of kerogen), which is considered the inert organic matter. The kerogen quality of the analyzed samples can be considered as very good to fair; the TOC content ranges from 1.64 to 8.37 wt% with most of them containing between 2 and 4 wt%. The grain density of these examined samples is in the range of 2.3–2.63 g/cc. The TOC and density of the samples have an inversely proportional relationship whereas the TOC and the specific surface area (BET) has a positive correlation. The specific surface area (BET) of the examined samples is in the range of 1.97–9.94 m2/g. The examined samples are dominated by clay, primarily kaolinite and muscovite. Additionally, few samples have a higher proportion of quartz and calcite. The examined samples from the Middle East contain kerogen type III and IV. Only two samples (JF2-760 and SQ1-1340) contain type I and type II kerogen. Considering Tmax and Hydrogen Index (HI), all of the samples are considered immature to early mature. Rock–Eval (S2) and TOC plotting indicate that most of the samples have very poor source rock potential only with an exception of one (JF2-760), which has a fair-to-good source rock potential
Leaching of copper and gold concentrate in the presence of halides
Get PDFIonometallurgy is a new trend to utilise ionic liquids as alternative green solvents for oxidic and sulfidic copper minerals. It has broad potential for traditional pyrometallurgy and hydrometallurgy. Ionometallurgy utilises ionic liquids (ILs), highly potent complexing ligands (chloride), to process oxide and copper sulfide minerals. This work focused on using the deep eutectic solvents (DES) of ionic liquids, which and provide alternative options for processing various metals, alloys, and concentrates.
For this job, various analytical methods were used to determine the copper concentrate and its residue after leaching (MLA-SEM and XRPD), quantify the elements in the solution (IC and ICP-OES/MS) and explain the oxidation behaviour (CV and UV-Vis spectroscopy). Combining the analytical and electrochemical methods to the leaching experiment provided the control to improve the results and understand its oxidation behaviour.
Chosen DES, Oxaline (ChCl + oxalic acid, 1:1), and Ethaline (ChCl + ethylene glycol, 1:2) were tested and enhanced on the actual copper concentrates with and without oxidative additives (FeCl3 and I2). Those oxidative additives are selected for leaching experiments by their redox potential in Ethaline.
However, there are many acceptable values; the most exciting result related to Ethaline plus iodine was the potential leaching system for chalcopyrite and copper-gold concentrates leaching. Because ion chromatography (IC) and UV-Vis’s analysis confirm iodine oxidizes the Cu+ species quickly in Ethaline. Whilst identical results and oxidation behaviour appeared in chalcocite (Cu2S), chalcopyrite (CuFeS2) and copper-gold concentrates leaching.
During the iodine reduction to iodide in the system, IC proved that chalcopyrite releases the Fe3+, oxidizing the chalcopyrite particles. Also, iodine oxidized the natural gold in copper-gold concentrate successfully, and gold concentration quantified ICP-MS and MLA-SEM proved there is no visible gold in the leaching residue.
Based on the optimal Ethaline + I2 leaching condition, the copper concentrate was carried out with the bottle roller leaching to represent the tank leaching. Thus, DES shows that it has a high potential to be continued to scale up the experiment. Also, water was given to the Ethaline leaching system, and water had a good influence on the leaching due to reducing the viscosity and saving the Ethaline amount. Hence Ethaline plus water is used for the copper ore leaching in the column, and it can be seen that Ethaline + I2 with water (up to 20%) has a high potential to process the low-grade copper sulfide ores.:Acknowledgements
Abstract
Abbreviations
TABLE OF CONTENTS
CHAPTER ONE – INTRODUCTION OF COPPER PROCESSING TECHNOLOGIES
1.1. Overview
1.2. Copper
1.3. Gold
1.4. Hydrometallurgy and pyrometallurgy of copper and gold
1.5. Current copper and gold concentrate processing methods
1.6. An alternative copper concentrate processing method
Summary of chapter 1
CHAPTER TWO – FUNDAMENTALS FOR PROCESS DEVELOPING
2.1. Introduction
2.2. Effect of temperature and stirring in leaching
2.3. Analytical methods and experimental
2.4. Experimental for leaching
2.5. Discussion of experimental errors
CHAPTER THREE: ANALYTICAL EXPERIMENTS FOR LEACHING
3.1. Introduction
3.2. Analysis of copper concentrate
3.3. Cyclic voltammetry
3.4. UV-Vis spectroscopy analysis of target metals
3.5. Metals solubility in DES
3.6. Summary and conclusions
CHAPTER FOUR: FUNDAMENTAL LEACHING EXPERIMENT AND INITIAL INVESTIGATION
4.1. Introduction
4.2. Initial study and fundamental leaching experiments
4.3. Study of mineral oxidation
4.4. Deep eutectic solvents leaching
4.5. Chapter summary and conclusion
CHAPTER FIVE: LEACHING OF MODEL SYSTEMS IN ETHALINE WITH OXIDATIVE ADDITIVES
5.1. Introduction
5.2. Iodine effect on Cu2S and CuS leaching in Ethaline
5.3. Ferric chloride effect on CuS and Cu2S leaching
5.4. Leaching of natural gold in Ethaline with the presence of iodine
5.5. Cyclic voltammetry investigation of Cu+/2+ sulfides in DES
5.6. Chapter summary and conclusion
CHAPTER SIX: LEACHING OF COPPER-GOLD CONCENTRATES IN DES AND WITH OXIDATIVE ADDITIVES
6.1. Introduction
6.2. Effect of ferric chloride (FeCl3)
6.3. Effect of iodine (I2)
6.4. Electrochemical and spectroscopic analysis of copper-gold concentrate leachates
6.6. Chapter summary and conclusion
CHAPTER SEVEN: OVERALL CONCLUSION AND FUTURE WORK
7.1. Overall conclusions
7.2. Recommendations for future research
CHAPTER EIGHT: APPENDIX
8.1. Chemicals and materials
8.2. Appendix
Reference