8 research outputs found

    Adsorption of Pb(II) from Aqueous Solution using Dendritic Fibrous Type SBA-15 (DFSBA-15)

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    The presence of heavy metals in the environment is undeniably harmful and toxic to living things, where the presence of Pb(II) inside human foods and drinks results in various diseases. The use of adsorption as a method of wastewater treatment is widespread, and effective adsorption performance depends on appropriate adsorbent selection. In this research, dendritic fibrous type SBA-15 (DFSBA-15) was prepared and used for lead (Pb(II)) adsorption. The physicochemical properties of the DFSBA-15 were characterized using TEM, BET, and FTIR. The characterization analyses confirmed the formation of fibrous morphology, moderate surface area, and bulk -OH. Several factors, including contact time (min), adsorbent dosage (g/L), pH, and initial concentration (mg/L), were examined for Pb(II) adsorption. The best adsorption performance (89.88%) was attained at 180 min, 1 g/L of adsorbent dosage, pH 5, and 100 mg/L of Pb(II) initial concentration. Pseudo-second-order reaction type and Langmuir isotherm provided good fits to the experimental data, with R2 ≥ 0.9943 and R2 = 0.9982, respectively. In short, the DFSBA-15 exhibits great potential for excellent Pb(II) removal

    Occurrence and Removal of Persistent Organic Pollutants (POPs)

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    Since the revelation in the detection of the persistent organic pollutants (POPs) in industrial wastewater in the early 1990s, a notable progress has been achieved on the research and different removal applications or methods of this challenge at hand. This book chapter entails a decent understanding on the occurrence, effects, and amputation of POPs in the water sector in advancement of municipal performances of treating industrial wastewaters and environment at large. This current chapter also presents an overview of research associated to the amputation of persistent organic pollutants (POPs) from various water bodies, i.e., river sediments, sewage plants, industrial sludges, and wastewater. Also, discussing the relationships with actual pre-treatment and removal rates. Vital characteristics such as the wastewater matrix, location, sources of POPs, materials and modules, operational parameters and problems are presented with a clear focus on removal of these organic pollutant’s different sources (like, textile wastewater). The particular methods to the removal of POPs can be associated with the application of ultrafiltration, nanofiltration and reverse osmosis as advanced treatment stages are considered in correlation with the textile wastewater characteristics and removal efficiencies requirements. This gives significance to the amalgamation of physico-chemical and biological treatment with membrane processes which is likely to represent an efficient solution for the removal of POPs from textile wastewater. However, since membrane fouling and hydrophilicity are apparent in the execution of this process, this chapter also covers the effective strategies like fabrication of membrane with a suitable additive to counterattack these challenges, which are often used in membrane technological research. This chapter also proposes an updated understanding of fouling and improvement of membrane properties

    Sustainable Synthesis of Cadmium Sulfide, with Applicability in Photocatalysis, Hydrogen Production, and as an Antibacterial Agent, Using Two Mechanochemical Protocols

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    CdS nanoparticles were successfully synthesized using cadmium acetate and sodium sulfide as Cd and S precursors, respectively. The effect of using sodium thiosulfate as an additional sulfur precursor was also investigated (combined milling). The samples were characterized by XRD, Raman spectroscopy, XPS, UV-Vis spectroscopy, PL spectroscopy, DLS, and TEM. Photocatalytic activities of both CdS samples were compared. The photocatalytic activity of CdS, which is produced by combined milling, was superior to that of CdS, and was obtained by an acetate route in the degradation of Orange II under visible light irradiation. Better results for CdS prepared using a combined approach were also evidenced in photocatalytic experiments on hydrogen generation. The antibacterial potential of mechanochemically prepared CdS nanocrystals was also tested on reference strains of E. coli and S. aureus. Susceptibility tests included a 24-h toxicity test, a disk diffusion assay, and respiration monitoring. Bacterial growth was not completely inhibited by the presence of neither nanomaterial in the growth environment. However, the experiments have confirmed that the nanoparticles have some capability to inhibit bacterial growth during the logarithmic growth phase, with a more substantial effect coming from CdS nanoparticles prepared in the absence of sodium thiosulfate. The present research demonstrated the solvent-free, facile, and sustainable character of mechanochemical synthesis to produce semiconductor nanocrystals with multidisciplinary application.DFG, 248198858, GRK 2032: Grenzzonen in urbanen Wassersysteme

    Técnicas no convencionales para la remediación de contaminantes orgánicos persistentes (COP): Revisión sistemática.

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    Este estudio asumió el objetivo de analizar aspectos más apreciables en el estudio de las técnicas no convencionales para la remediación de contaminantes orgánicos persistentes; y se desarrolló 3 problemas mediante planteamiento de una metodología cualitativa aplicada; permitiendo la selección de 80 literaturas, donde se incluyeron 20 más completas al estudio. Se obtuvo que las técnicas no convencionales más desarrolladas para la eliminación de COPs son, un 60% la aplicación de fotocatalizadores, seguido del proceso avanzado de oxidación (AOPs) con 35% de veces empleado y en menor cantidad al electro oxidación con 5%. Los COP con mayor persistencia y toxicidad en el ambiente son el ácido perfluorooctanoico (C8 HF15 O2), con 18% veces empleados, también con 18% se encuentra el Pentaclorofenol (C6 Cl5 OH), de las ventajas y desventajas de los procesos de tratamientos no convencionales para la eliminación de COP se enfoca en procesos de operación, presentando mayores ventajas aquellos que no requieren adición de productos como la electro oxidación, o por presentar alta eficiencia como la fotocatálisis, la cual presenta en promedio 65% a 91% de degradación de los COP, también la reacción de fenton es ampliamente aceptada como remediador de contaminantes por COP por su alta eficiencia

    Synthesis and Characterization of Nanoporous Resin Particles for Water Purification

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    Through progressive industrialization and the relentless consumption of natural raw materials, man is exerting a negative influence on his habitat. In particular, water as the basis of life and almost all processes of our economy is contaminated by various pollutants due to excessive use and insufficient purification. Here, oxyanions, heavy metal ions and organic pollutants pose a high risk to aquatic habitats and ultimately to humans. Due to insufficient removal, they also contribute to the loss of non-renewable raw materials for industrial cycles. Due to a mostly low effect concentration and potential interactions with diverse living organisms, the removal of many contaminants is extremely important to avoid further altering existing ecosystems. Adsorption represents an energy-efficient method of removal using adsorbents suitable for this purpose. Highly cross-linked resin polymers such as poly(melamine-co-formaldehyde) (PMF) with its excellent chemical resistance, high number of functional groups and ease of preparation, represent promising starting points for adsorbents. This dissertation describes the colloidal aqueous synthesis of nanoporous resin particles (e.g. PMF) by templating with SiO2 nanoparticles (SiO2 NPs), which are subsequently used to adsorb water pollutants. An overall goal of this work consists of elucidating the mechanism for particle and pore formation by systematically varying various synthesis parameters. Electron microscopy, N2-soprtion and particle size measurement are used to analyze the morphology, size and pore structure of the particles. Comprehensive investigations thus allow to determine the influence of each tested synthesis parameter on these properties. A very important goal, especially for future large-scale applicability, is the colloidal production of uniform particles, which have both a high ordered porosity and particle diameters in the range of a few micrometers. This enables an application as a fixed-bed adsorber that can be flowed through. This goal is closely linked to the mechanistic elucidation of pore and particle formation in the synthesis. The prepared nanoporous PMF particles were tested for various adsorption applications after their characterization. In order to obtain a comprehensive picture of the applicability of PMF particles, experiments with oxyanions, with pharmaceuticals as representatives of organic pollutants and with heavy metal ions will be carried out respectively. On the one hand, these experiments will focus on investigating the adsorption performance and mechanism of PMF with the respective pollutant. On the other hand, the influence of the changed porosity on the adsorption mechanism is investigated by using different particles of a varied synthesis parameter. Sulfate and phosphate ions were investigated in the oxyanion class. Extremely high separation rates were demonstrated for both ions, significantly outperforming previous commercially available materials. In experiments concerning a potential selective adsorption and thus separation of both species, the PMF/SiO2 hybrid particles, in which the template had not yet been removed, showed a selective sulfate adsorption. The immobilization of heavy metal ions was analyzed with special focus on the simultaneous separation of the Cu2+ ions and respective anions used here. Investigations of the adsorbent after the adsorption experiments by means of electron microscopy, X-ray scattering and electron spin resonance spectroscopy elucidated the adsorption mechanism, which had been insufficiently analyzed so far. Here, adsorption and surface-induced precipitation were identified as partially separate subprocesses, both of which are responsible for the separation of both metal and anions from solution. In adsorption experiments with the monovalent ions nitrate and chloride, a two-step uptake process was identified, which was mathematically described for the first time via a new adsorption isotherm. In the scope of organic water pollutants, the separation of the pharmaceutical diclofenac is being tested. In particular, the adsorption of pharmaceuticals is an urgent issue due to their low effect concentration and ubiquity in surface and tap waters. Pharmaceutical separation using PMF has hardly been investigated worldwide despite its promising properties. In these experiments, particles templated with SiO2 NPs of different sizes and stabilized in different ways were tested. This resulted in pore systems that varied from each other especially in their accessibility of the pore system and in the diameter of the connecting channels between the main cavities. These characteristics significantly affected the adsorption capacity and separation rates in low concentration range. A final goal is to synthesize a resin network that uses an equally highly functional triazine-based monomer instead of melamine. The monomer 2,4,6-tris(2,4,6-trihydroxyphenyl)-1,3,5-triazine (3PT) possesses nine hydroxyl groups each, whereby a polymer based on it should exhibit strongly modified adsorption properties compared to PMF. This monomer was used in an aqueous polymerization analogous to PMF to produce a previously unknown polymer network, which was designated P(3PT-F). Here, templating was omitted because the newly prepared material already exhibited intrinsic nanoporosity due to the size of the 3PT monomer. In subsequent adsorption experiments, very high separation rates were demonstrated for the toxic metal ions Pb2+, Cd2+ and Ni2+. In realistic initial concentrations, the contamination was reduced to drinking water quality in each case. P(3PT-F) also showed highly selective removal of Pb2+ over the common ions Ca2+, Mg2+, K+ and Fe2+. As fundamental evidence, reusability was also demonstrated by complete desorption with dilute HCl and subsequent re-adsorption without significant reduction in capacity. Overall, starting from the fundamental study of PMF particle synthesis, a more general understanding of aqueous dispersion polymerization of hydrophobic resins was first derived and templating with hydrophilic SiO2 NPs was implemented. With the help of understanding the particle growth processes and interactions responsible for templating, the properties of the resulting particles could be controlled. Subsequently, the influence of the changed porosity in particular on the separation performance could be investigated in the adsorption studies. In addition, it was possible to analyze which interactions PMF enters into with the respective pollutant types. By replacing the monomer melamine with a hydroxyl-containing monomer, a novel resin polymer could be produced. With its altered porosity and reactivity, this can now serve as a new starting point for adsorption experiments with strongly altered adsorption performance, e.g. towards heavy metal ions.:Abstract 1 Kurzfassung 5 List of Publications 9 First-Author Publications 9 Co-Author Publications 10 Patent 12 Conference Proceedings 12 Oral Presentations 12 Poster 12 List of Figures 13 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 14 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 15 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 16 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 18 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 19 List of Tables 21 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 21 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 21 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 22 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 22 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 23 Abbreviations 25 Symbols 26 1. Introduction 1 2. Objectives and Experimental Design 5 3. Scientific Background 11 3.1. Poly(melamine-co-formaldehyde) 11 3.1.1. Polymerization Mechanism 11 3.1.2. Synthesis Strategies for the Preparation of Porous PMF Particles. 13 3.1.3. Fields of Application of PMF 13 3.2. Adsorption 15 3.2.1. Adsorption Isotherms and Mathematical Modeling 16 3.3. Surface Precipitation 20 4. Fundamentals of Instrumental Analytics 23 4.1. Gas Sorption Measurements 23 4.1.1. Determination of Pore Sizes 26 4.1.2. Determination of Specific Surface Area 27 4.2. Transmission Electron Microscopy 29 4.3. Inductively Coupled Plasma Optical Emission Spectroscopy 31 Results and Discussion 33 Chapter Overview 33 5. Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal 37 Graphical Abstract 37 Abstract 37 1. Introduction 38 2. Results and Discussion 39 2.1. Synthesis and Characterization of the PMF Particles 40 2.2. Sorption Experiments 47 3. Materials and Methods 54 3.1. Materials 54 3.2. Methods 54 3.3. Synthesis of the PMF Particles 56 3.4. Water Treatment Experiments 57 4. Conclusions 59 6. Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal 65 Graphical Abstract 65 Abstract 65 1. Introduction 66 2. Materials 68 3. Methods 68 3.1. Synthesis of the PMF particles 70 3.2. Water treatment experiments with diclofenac solution 72 3.3. Theoretical model 72 3. Results and Discussion 73 3.1. Synthesis and characterization of the PMF particles 74 3.2. Adsorption of Pharmaceutics 80 4. Conclusion 84 7. Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles 89 Graphical Abstract 89 Abstract 89 1. Introduction 90 2. Materials and methods 91 2.1. Materials 91 2.2. Synthesis of the Poly(melamine-co-formaldehyde) particles 92 2.3. Methods 93 2.4. Water treatment experiments 96 3. Results and discussion 97 3.1. Synthesis and characterization of the PMF particles 98 3.2. Cu2+ uptake experiments 102 3.3. Mechanism for Cu2+ and Anion Removal 115 3.4. Investigation of other heavy metal salts 116 4. Conclusions 117 8. SiO₂ Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles 121 Graphical Abstract 121 Abstract 121 1. Introduction 122 2. Materials and methods 123 2.1. Materials 123 2.2. Methods 124 2.3. Synthesis of the PMF particles 125 2.4. Water treatment experiments 128 2.5. Theoretical model 129 3. Results and Discussion 132 3.1. PMF-Std 133 3.2. Influence of the reaction mixture composition 136 3.3. Variation of the process parameters 140 3.4. Conclusion on the templating mechanism for PMF-Std 146 3.5. Acquiring µm-sized porous PMF particles for adsorption application 149 3.6. Adsorption experiments with K2Cr2O7 solution 151 4. Conclusion 155 9. Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions 161 Graphical Abstract 161 Abstract 161 1. Introduction 162 2. Materials and methods 163 2.1. Materials 163 2.2. Synthesis 164 2.3. Characterization 166 2.4. Batch adsorption experiments 169 2.5. Calculation and theoretical models 170 3. Results and discussion 172 3.1. Synthesis and characterization of the polymer particles 172 3.2. Adsorption experiments with Ni2+, Cd2+, and Pb2+ onto P(3PT-F)-3L 178 4. Conclusions 184 10. Conclusion and Outlook 191 Contribution to Publications 197 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal 197 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal 198 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles 199 SiO₂ Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles 200 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions 201 Danksagung 203 Appendix 205 References 207 Eidesstattliche Versicherung 217Durch fortschreitende Industrialisierung und den schonungslosen Verbrauch natürlicher Rohstoffe übt der Mensch negativen Einfluss auf seinen Lebensraum aus. Insbesondere Wasser als Grundlage des Lebens und fast aller Prozesse unserer Wirtschaft wird durch eine übermäßige Nutzung und unzureichende Reinigung mit diversen Schadstoffen kontaminiert. Hierbei stellen Oxyanionen, Schwermetallionen und organische Schadstoffe ein hohes Risiko für aquatische Lebensräume und letztendlich auch den Menschen dar. Durch unzureichende Entfernung tragen sie außerdem zum Verlust nicht-erneuerbarer Rohstoffe für industrielle Kreisläufe bei. Durch eine meist geringe Effektkonzentration und potentielle Wechselwirkungen mit diversen Lebewesen ist die Entfernung vieler Verunreinigungen extrem wichtig, um bestehende Ökosysteme nicht weiter zu verändern. Adsorption stellt eine energieeffiziente Methode zur Entfernung dieser Schadstoffe durch hierfür geeignete Adsorbentien dar. Hochgradig vernetzte Harzpolymere wie Poly(melamin-co-formaldehyd) (PMF) stellen mit ihrer sehr hohen chemischen Beständigkeit, einer hohen Zahl funktioneller Gruppen und einfachen Herstellbarkeit einen vielversprechenden Ausgangspunkt für Adsorbentien dar. Diese Dissertation beschreibt die kolloidale, wässrige Synthese nanoporöser Harzpartikel (z. B. PMF) durch eine Templatierung mit SiO2 Nanopartikeln (SiO2 NPs), welche anschließend zur Adsorption von Wasserschadstoffen eingesetzt werden. Ein übergeordnetes Ziel dieser Arbeit besteht aus der Aufklärung des Mechanismus zur Partikel- und Porenbildung durch systematische Variation verschiedener Syntheseparameter. Mittels Elektronenmikroskopie, N2-Sorption und Partikelgrößenmessung wird die Morphologie, Größe und Porenstruktur der Partikel analysiert. Umfassende Untersuchungen ermöglichen somit, den Einfluss der einzelnen getesteten Syntheseparameter auf diese Eigenschaften zu bestimmen. Ein sehr wichtiges Ziel, besonders für eine zukünftige großtechnische Anwendbarkeit, ist dabei die kolloidale Herstellung uniformer Partikel, welche sowohl eine hohe geordnete Porosität als auch Partikeldurchmesser im Bereich einiger Mikrometer aufweisen. Dies ermöglicht einen Einsatz als durchströmbaren Festbett-Adsorber. Dieses Ziel ist eng mit der mechanistischen Aufklärung der Poren- und Partikelbildung in der Synthese verknüpft. Die hergestellten nanoporösen PMF-Partikel wurden nach ihrer Charakterisierung für verschiedene Adsorptionsanwendungen getestet. Um ein umfassendes Bild über die Einsetzbarkeit von PMF-Partikeln zu erhalten, sollen jeweils Versuche mit Oxyanionen, mit Schwermetallionen und mit Pharmazeutika als Vertreter organischer Schadstoffe durchgeführt werden. Bei diesen Versuchen steht zum einen die Untersuchung der Adsorptionsleistung und des Adsorptionsmechanismus des jeweiligen Schadstoffes an PMF im Vordergrund. Zum anderen wird durch die Verwendung verschiedener Partikel, bei welchen ein einzelner Syntheseparameter variiert wurde, der Einfluss der veränderten Porosität auf den Adsorptionsmechanismus untersucht. Sulfat- und Phosphationen wurden in der Klasse der Oxyanionen untersucht. Für beide Ionen wurden extrem hohe Abtrennraten nachgewiesen, welche bisherige kommerziell erhältliche Materialien signifikant übertraf. In Versuchen hinsichtlich einer potentiellen selektiven Adsorption und somit Trennung beider Spezies, zeigten die PMF/SiO2-Hybridpartikel, bei welchen das Templat noch nicht entfernt wurde, eine selektive Sulfatadsorption. Die Immobilisierung von Schwermetallionen wurde mit besonderem Fokus auf die gleichzeitig auftretende Abtrennung der dafür verwendeten Cu2+-Ionen und jeweiliger Anionen analysiert. Durch Untersuchungen des Adsorbens nach den Adsorptionsversuchen mittels Elektronenmikroskopie, Röntgenstreuung und Elektronenspinresonanz-Spektroskopie wurde der bisher unzureichend analysierte Adsorptionsmechanismus aufgeklärt. Hierbei wurden Adsorption und oberflächeninduzierte Fällung als separate Teilprozesse identifiziert, welche beide jeweils für die Abscheidung von sowohl Metall- als auch Anionen aus der Lösung verantwortlich sind. Bei Adsorptionsversuchen mit den einwertigen Ionen Nitrat und Chlorid wurde ein zweistufiger Prozess identifiziert, welcher erstmals über eine neue Adsorptionsisotherme mathematisch beschrieben wurde. Im Bereich organischer Wasserschadstoffe wird die Abtrennung des Pharmazeutikums Diclofenac getestet. Insbesondere die Adsorption von Pharmazeutika stellt aufgrund von deren geringen Effektkonzentration und Allgegenwärtigkeit in Oberflächen- und Leitungswässern ein dringliches Thema dar. Die Pharmazeutika-Abtrennung mittels PMF wurde trotz seiner vielversprechenden Eigenschaften weltweit bisher kaum untersucht. Im Rahmen dieser Versuche wurden Partikel getestet, welche mit unterschiedlich großen und unterschiedlich stabilisierten SiO2 NPs templatiert wurden. Dadurch entstanden Porensysteme, die besonders in derer Zugänglichkeit ihres Porensystems und in dem Durchmesser der Verbindungskanäle zwischen den Hauptkavitäten voneinander variierten. Diese Eigenschaften wirkten sich signifikant auf die Adsorptionskapazität und die Abtrennraten im niedrigen Konzentrationsbereich aus. Ein abschließendes Ziel ist die Synthese eines Harznetzwerkes, welches statt Melamin auf einem ebenso hochfunktionellen, triazinbasierten Monomer basiert. Das Monomer 2,4,6-Tris(2,4,6-trihydroxyphenyl)-1,3,5-triazin (3PT) besitzt jeweils neun Hydroxylgruppen, wodurch ein darauf basierendes Polymer stark veränderte Adsorptionseigenschaften gegenüber PMF aufweisen soll. Mit diesem Monomer wurde in einer analog zu PMF durchgeführten wässrigen Polymerisation ein bisher unbekanntes Polymernetzwerk hergestellt, welches als P(3PT-F) bezeichnet wurde. Hierbei wurde auf Templatierung verzichtet, da das neu hergestellte Material bereits intrinsische Nanoporosität durch die Größe des verwendeten 3PT-Monomers aufwies. In anschließenden Adsorptionsversuchen wurden sehr hohe Abtrennraten für die toxischen Metallion Pb2+, Cd2+ und Ni2+ nachgewiesen. In realistischen Ausgangskonzentrationen wurde die Kontamination mit diesen Ionen jeweils auf Trinkwasserqualität reduziert. P(3PT-F) zeigte außerdem eine sehr selektive Abtrennung von Pb2+ gegenüber den häufig vorkommenden Ionen Ca2+, Mg2+, K+ und Fe2+. Als grundlegender Beweis konnte eine Wiederverwendbarkeit durch die vollständige Desorption mit verdünnter HCl gezeigt werden und eine anschließende erneute Adsorption ohne signifikante Verringerung der Kapazität. Insgesamt wurde ausgehend von der grundlegenden Untersuchung der PMF-Partikelsynthese erst ein generelleres Verständnis der wässrigen Dispersionspolymerisation hydrophober Harze abgeleitet und die Templatierung mit hydrophilen SiO2 NPs implementiert. Mithilfe des Verständnisses der Partikelwachstumsprozesse und der Wechselwirkungen, welche für die Templatierung verantwortlich sind, konnten die Eigenschaften der entstehenden Partikel gesteuert werden. Im Rahmen der Adsorptionsuntersuchungen konnte anschließend der Einfluss insbesondere der veränderten Porosität auf die Abtrennleistung untersucht werden. Außerdem konnte analysiert werden, welche Wechselwirkungen PMF mit den jeweiligen Schadstoffarten eingeht. Durch den Austausch des Monomers Melamin gegen das hydroxylhaltiges Monomer 3PT konnte ein neuartiges Harzpolymer hergestellt werden. Dieses kann mit seiner veränderten Porosität und Reaktivität nun als neuer Ausgangspunkt für Adsorptionsexperimente mit stark veränderter Adsorptionsleistung z. B. gegenüber Schwermetallionen dienen.:Abstract 1 Kurzfassung 5 List of Publications 9 First-Author Publications 9 Co-Author Publications 10 Patent 12 Conference Proceedings 12 Oral Presentations 12 Poster 12 List of Figures 13 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 14 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 15 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 16 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 18 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 19 List of Tables 21 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 21 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 21 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 22 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 22 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 23 Abbreviations 25 Symbols 26 1. Introduction 1 2. Objectives and Experimental Design 5 3. Scientific Background 11 3.1. Poly(melamine-co-formaldehyde) 11 3.1.1. Polymerization Mechanism 11 3.1.2. Synthesis Strategies for the Preparation of Porous PMF Particles. 13 3.1.3. Fields of Application of PMF 13 3.2. Adsorption 15 3.2.1. Adsorption Isotherms and Mathematical Modeling 16 3.3. Surface Precipitation 20 4. Fundamentals of Instrumental Analytics 23 4.1. Gas Sorption Measurements 23 4.1.1. Determination of

    Persistent Organic Pollutants (POPs)

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    Persistent organic pollutants (POPs) are toxic organic compounds that resist environmental degradation through biological, chemical, and photolytic processes. Many POPs are currently used as pesticides, pharmaceuticals, solvents, and industrial chemicals. Because of their persistence, POPs bioaccumulate and adversely affect human health and the environment. Persistent Organic Pollutants (POPs) - Monitoring, Impact and Treatment deals with several aspects of POP monitoring, occurrence, impact, and treatment technologies. The book is divided into two sections containing nine chapters that address such topics as the effect of POPs on wildlife, their role in hepatocarcinogenesis, treatment of POPs in wastewater, and much more
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