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Megaporous adsorbents were prepared based on nonwoven polyethylene terephthalate (PET) fabrics and functionalized by covalent modification with polyvinylamine (PVAm) or monotriazinyl-β-cyclodextrin-substituted polyvinylamine (PVAm-MCT-β-CD). Mechanical properties of the resulting fabrics were maintained, as judged by tensile strength tests and scanning electron microscopy. Exceptional porosity (≥82%) and preserved hydrodynamic characteristics (Pe ≥ 63) indicated excellent structural stability when packed. The performance of the constructed adsorbents was evaluated with high molecular weight (proteins) and low molecular weight (dyes) model compounds. The static binding capacity (SBC) for bovine serum albumin (BSA) was 79.7 ± 1.3 and 92.9 ± 8.2 mg/g for PVAm-modified and PVAm-MCT-β-CD-modified fabrics, respectively. The mentioned materials also adsorbed Orange II, an acidic dye (92.4 ± 2.6 and 101.9 ± 2.6 mg/g, respectively), indicating that the hydrophobicity was a prevailing binding mechanism operating at a pH close to isoelectric point. SBC for lysozyme and toluidine blue O (TBO, a basic dye) onto PVAm-MCT-β-CD functionalized PET was 52.7 ± 5.1 and 73.3 ± 0.6 mg/g, respectively. TBOs have also shown some affinity for PVAm functionalized PET, but this was most likely to be mediated by hydrophobicity. On the other hand, operating at a superficial velocity of 90 cm/h, dynamic binding capacity for BSA was 11.4 ± 3.5 and 2.5 ± 0.6 mg/g indicating the importance of possible aggregation mechanisms during protein binding at equilibrium. Thus, PET-based adsorbents require further functional improvement for chromatography applications. However, the easy-to-construct, scalable nonwoven adsorbents deserve further attention as a potential alternative to packed-bed-chromatography adsorbents.

Konventionelle Techniken zur Trink- und Abwasseraufbereitung zur Entfernung von perfluorierten Tensiden (PFC) funktionieren eher ungenügend. Daher sind neue Adsorber für PFCs erforderlich. Im Forschungsprojekt wurden textilbasierte Adsorber auf Basis beschichteter Polyesterfasern mit verschiedenen Polyelektrolyten entwickelt. Die textilbasierten Adsorber wurden per Foulard-Ausrüstungsmethode hergestellt, was zu langlebigen, leistungsstarken und kostengünstigen Adsorbentien für die Entfernung von PFCs aus Wasser führt. Aus dem kontaminierten Grundwasser aus Düsseldorf und eines ehemaligen Textilveredlungsbetriebs in Bielefeld wurden ~95 bzw. 85 % der lang- und kurzkettigen PFCs reduziert. Dagegen zeigte das stark mit kurzkettigen PFC belastete Grundwasser aus der Papierschlammentsorgung aus Rastatt eine geringere Elimination für kurzkettige PFC. Der daraus resultierende amphiphile Charakter bewirkt eine starke Reduzierung der Oberflächenspannung von Wasser, wobei die hydrophile Kopfgruppe mit der wässrigen Phase wechselwirkt, während die hydrophobe Kette wasser-, öl- und fettabweisend ist. Ihre Oberflächenaktivität ist deutlich höher als die der analogen Kohlenwasserstofftenside [1, 2]. Aufbauend auf dieser Eigenschaft wurden daher viele fluorcarbonhaltige Ausrüstungschemikalien zur Hydrophobierung, Oleophobierung bzw. als Anti-Schmutzausrüstung für Textilien entwickelt. Sie finden z.B. für Outdoorjacken (Hydrophobierung), Schutzkleidung (Ölabweisung, Schadstoffabweisung) oder für Möbel oder Teppiche Anwendung um eine einfachere Reinigung zu ermöglichen.

Energy consumption by air-conditioning is expansive and leads to the emission of millions of tons of CO

The wet chemical deposition of solution processed transparent conducting oxides (TCO) provides an alternative low cost and economical deposition technique to realize large-areas of conducting films. Since the price for the most common TCO Indium Tin Oxide rises enormously, Aluminum Zinc Oxide (AZO) as alternative TCO reaches more and more interest. The optoelectronical properties of nanoparticle coatings strongly depend beneath the porosity of the coating on the shape and size of the used particles. By using bigger or rod-shaped particles it is possible to minimize the amount of grain boundaries resulting in an improvement of the electrical properties, whereas particles bigger than 100 nm should not be used if highly transparent coatings are necessary as these big particles scatter the visible light and lower the transmittance of the coatings. In this work we present a simple method to synthesize AZO particles with different shape and size, but comparable electronical properties. We use a simple, well reproducible polyol method for synthesis and influence the shape and size of the particles by adding different amounts of water to the precursor solution. We can show that the addition of aluminum as dopant strongly hinders the crystal growth but the addition of water counteracts this, so that both, spherical and rod-shaped particles can be obtained.

Porphyrin assemblies display interesting photophysical properties and a relatively high thermal stability. Moreover,meso-functionalized porphyrins with virtually fourfold symmetry can be relatively readily synthesized from pyrrole and the appropriate aldehyde. A number of metallo derivatives of 5,10,15,20-tetrakis(4-cyanophenyl)porphyrin, where the N atom of the linear cyano group can act both as a donor for coordination bonds or as an acceptor for hydrogen bonds, have been structurally characterized by single-crystal X-ray analysis. The supramolecular and structural chemistry of the corresponding 2- and 3-cyanophenyl isomers of the parent porphyrin, however, has remained largely unexplored. The crystal structure of [5,10,15,20-tetrakis(3-cyanophenyl)porphyrinato]copper(II) (CuTCNPP) nitrobenzene trisolvate, [Cu(C48H24N8)]·3C6H5NO2, has been determined at 80 K by synchrotron single-crystal X-ray diffraction. CuTCNPP exhibits aC2h-symmetric ααββ conformation, despite an unsymmetrical crystal environment, and is situated on a crystallographic centre of symmetry. The CuIIion adopts a genuine square-planar coordination by the four pyrrole N atoms. The 24-membered porphyrin ring system shows no marked deviation from planarity. In the crystal, the CuTCNPP molecules and two nitrobenzene molecules are face-to-face stacked in an alternating fashion, resulting in corrugated layers. The remaining nitrobenzene guest molecule per CuTCNPP resides in the region between four neighbouring columnar stacks of CuTCNPP and sandwiched nitrobenzene molecules, and is disordered over four positions about a centre of symmetry.

Textile catalysts are a new approach utilizing immobilization of different classes of catalysts onto textile materials such as polyethylene terephthalate and polyamide. Robust, inexpensive fibrous materials are chosen because they are available in many variations. By a photochemical approach a series of different supported organocatalysts (organotextile catalysts) has been prepared, showing high catalytic activity and good reusability. The aim of this concept article is to present the scope, limits and open questions of our innovative approach. The working principle of the immobilization and its control parameters will be explained and the scope of useable catalysts is shown. Therefore we will show the significant influence of the anchoring group on loading and more importantly on catalyst activity. This concept is also applicable to organometallic catalysts and enzymes. Understanding the different phenomena allows us to develop “textile catalysts” as a new powerful tool for heterogeneous catalysis.

In this work, a pioneering study on the electrical properties of composite carbon nanofibres (CNFs) using current-sensitive atomic force microscopy (CS-AFM) has been demonstrated. CNFs are highly interesting materials which are usable in a wide array of applications

Although current desalination technologies are mature enough and advanced, the shortage of freshwater is still considered as one of the most pressing global issues. Therefore, there is a strong incentive to explore and investigate new potential methods with low energy consumption. We have previously reported that reversible thermally induced sorption/desorption process using polymeric hydrogels hold promise for water desalination with further development. In order to develop a more effective hydrogels architecture, polyelectrolyte moieties were introduced in this work as pendent chains and a thermally responsive polymer as network backbone using reversible addition-fragmentation chain transfer (RAFT) polymerisation. The ability of the comb-type polymeric hydrogels to desalinate water was evaluated. These hydrogels were proved to absorb water with low salinity from brine solution of 2 g L − 1 NaCl and release the absorbed water at relatively low temperature conditions of 50 ∘ C. The fraction of the grafted polyacrylic acid and the comb-chain length were varied to understand their influence on the swelling/deswelling behaviour for these hydrogels. The ionic fraction in the hydrogels and the resulting hydrophilic/hydrophobic balance are crucial for the proposed desalination process. In contrast, the comb-chain length impacted the swelling behaviour of hydrogels but showed relatively little influence on the dewatering process.

Although current desalination technologies are mature enough and advanced, the shortage of freshwater is still considered as one of the most pressing global issues. Therefore, there is a strong incentive to explore and investigate new potential methods with low energy consumption. We have previously reported that reversible thermally induced sorption/desorption process using polymeric hydrogels hold promise for water desalination with further development. In order to develop a more effective hydrogels architecture, polyelectrolyte moieties were introduced in this work as pendent chains and a thermally responsive polymer as network backbone using reversible addition-fragmentation chain transfer (RAFT) polymerisation. The ability of the comb-type polymeric hydrogels to desalinate water was evaluated. These hydrogels were proved to absorb water with low salinity from brine solution of 2 g L − 1 NaCl and release the absorbed water at relatively low temperature conditions of 50 ∘ C. The fraction of the grafted polyacrylic acid and the comb-chain length were varied to understand their influence on the swelling/deswelling behaviour for these hydrogels. The ionic fraction in the hydrogels and the resulting hydrophilic/hydrophobic balance are crucial for the proposed desalination process. In contrast, the comb-chain length impacted the swelling behaviour of hydrogels but showed relatively little influence on the dewatering process.

Despite their excellent flame retardant properties, polyphosphazenes are currently not used as flame retardant agents for textile finishing, because a permanent fixation on the substrate surface has failed so far. Here, we present the successful synthesis and characterization of a noncombustible and foam-forming polyphosphazene derivative, that can be immobilized durably on cotton and different cotton/polyester blended fabrics using photoinduced grafting reactions. The flame retardant properties are improved, a higher limiting oxygen index is found, and the modified textiles pass several standardized flammability tests. As flame retardant mechanism a synergistic effect between the immobilized polyphosphazene and the textile substrate was observed. The polyphosphazene finishing induces an earlier decomposition of the material with a reduced mass loss in thermogravimetric analysis. The decomposition of cotton and polyester leads to the formation of phosphorus oxynitride, which forms a protecting barrier layer on the fiber surface. In addition, the permanence of the flame retardant finishing was proven by laundry and abrasion tests.

The soil and groundwater of many old industrial areas are polluted by different environmental hazards. Because of their high toxicity and carcinogenic potential, chromate contaminations are especially problematic and a complete cleanup of such areas is necessary to avoid fatal environmental and sanitary impacts. Conventionally, decontamination is carried out by the removal of the soil and a long-term filtration of groundwater with various chromate-adsorbing materials over a period of many years. Efficient, reusable and cheap adsorbing materials, however, are still missing. Here, we present a new, cheap and reusable chromate-adsorbing substrate based on polyvinylamine-coated polyester fibers. The surface modification of the fibrous material is realized by common methods in textile finishing yielding a durable, high-performing and reusable adsorbent for water-dissolved chromate. The functionalized nonwoven fabric has a high binding capacity for chromate and the chromate concentration of highly polluted waters (with concentrations around 50 mg L−1) can easily be decreased below the limit of 50 μg L−1 recommended by the WHO. Moreover, the material is reusable after regeneration under aqueous alkaline conditions. The adsorption properties at different pH values were determined with different adsorption models. In addition, adsorption kinetics were evaluated using artificial and real life chromate-contaminated water samples.

Three established test methods employed for evaluating the abrasion or wear resistance of textile materials were compared to gain deeper insight into the specific damaging mechanisms to better understand a possible comparability of the results of the different tests. The knowledge of these mechanisms is necessary for a systematic development of finishing agents improving the wear resistance of textiles. Martindale, Schopper, and Einlehner tests were used to analyze two different fabrics made of natural (cotton) or synthetic (polyethylene terephthalate) fibers, respectively. Samples were investigated by digital microscopy and scanning electron microscopy to visualize the damage. Damage symptoms are compared and discussed with respect to differences in the damaging mechanisms.

A new strategy for the biological transformation of sugar-containing wastewaters from the textile desizing process to biogas was developed. Here, industrial liquors were separated from the following washing step by squeezing the impregnated fabrics after desizing. These waters exhibit a chemical oxygen demand of 40 g/L and allow a direct use in microbial biogas reactors without further treatment or accumulation. After reaching balanced conditions, the microbes continuously produce biogas. Moreover, the chemical oxygen demand can be reduced up to 75%. This new technology seems to be practicable and even attractive for small- and medium-sized enterprises with an annual cotton production down to 2000 t. At this stage, a reliable eco-balance of the overall process is still pending. Further investigations will be carried out soon.

Recikliranje i oporaba skupih plemenitih metala, poput platine, zlata, paladija i srebra, odnosno rijetkih i strateških metala, poput indija, galija i rijetki zemljanih metala iz otpadnih metala i otpadnih voda dobit će na važnosti u sljedećih nekoliko godina. Stoga je potrebno usmjeriti pozornost na iznalaženje potenijalno korisnih sekundarnih izvora i razvoj jeftinih i energetski štedljivih postupaka kojima bi se selektivno razdvojili i oporabili metali (urbano rudarstvo). Zajedno s elektroničkim otpadom, industrijski procesi i otpadna voda predstavljaju značajan izvor plemenitih metala. Nedavno smo uspješno razvili inovativni tekstilni filtarski materijal za adsorpciju metala temeljen na poliesterkim vlaknima oslojenim polivinilaminom. Površinske modifikacije vlaknatog materijala lako je postići konvencionalnim metodama tekstilne dorade i tako dobiti trajno adsorpcijsko sredstvo visoke učinkovitosti, a istovremeno niske cijene. Naši se rezultati temelje na uobičajenim postupcima teksilne dorade i na adsorpciji iona plemenitih metala ovisnoj o pH vrijednosti. Provedivost čitavog postupka prikazana je na postupku obrade vode bogate paladijem, dobivene od jednog njemačkog proizvođača tiskanih ploča. Pored toga, isti inovativni adsorpcijski materijal može se koristiti za pročišćavanje površinskih voda i tla zagađenih kromatima. Najnovija istraživanja usmjerena su na korištenje ovog materijala za selektivnu oporabu rijekih zemljanih metala iz industrijske proizvodnje FCC katalizatora za naftnu industriju., The recycling and recovery of high-prized noble metals such as platinum, gold, palladium and silver or rare and strategic metals like indium, gallium, and rare earth metals from scrap metals and wastewaters will be from steadily increasing importance within the next years. Therefore, the focus has to be set on the detection of potentially usable secondary resources and the development of inexpensive and energy-saving processes to separate and recover the metals selectively (urban mining). Beside electronic scrap industrial process and wastewaters represent a considerable source for noble metals. Recently, we have successfully developed an innovative metal-adsorbing textile filter material based on polyvinylamine-coated polyester fibers. The surface modification of the fibrous material is easy to realize with common methods in textile finishing yielding a durable, high-performing and even cheap adsorbent for water-dissolved metal ions. We present results on the general textile finishing procedure and the pH-depending adsorption of noble metal ions. The feasibility of the overall process is demonstrated on palladium containing process waters obtained from a German producer of curcuit boards. Moreover, the same innovative adsorber material is useful for the decontamination of chromate-polluted ground waters and soils. Our latest investigations focus their use in the selective recovery of rare earth metals from large-scale FCC catalyst production for the petroleum refining industry.

The influence of tetrapyridylporphyrins on agglomeration and solubility of palladium nanoparticles is tested. The comparison between 3-pyridyl- and 4-pyridyl-substituted porphyrins enables to distinguish between central and peripheric binding mode.

The enzymatic desizing of starch-sized cotton fabrics leads to wastewaters with an extremely high chemical oxygen demand due to its high sugar content. Nowadays, these liquors are still disposed without use, resulting in a questionable ecological pollution and high emission charges for cotton finishing manufacturers. In this paper, an innovative technology for the production of energy from textile wastewaters from cotton desizing was developed. Such desizing liquors were fermented by methane-producing microbes to biogas. For this purpose, a semi-industrial plant with a total volume of more than 500 L was developed and employed over a period of several weeks. The robust and trouble-free system produces high amounts of biogas accompanied by a significant reduction of the COD of more than 85%. With regard to growing standards and costs for wastewater treatment and disposal, the new process can be an attractive alternative for textile finishing enterprises in wastewater management, combining economic and ecological benefits. Moreover, the production of biogas from textile wastewaters can help to overcome the global energy gap within the next decades, especially with respect to the huge dimension of cotton pretreatment and, therefore, huge desizing activities worldwide.

Throughout human history, textiles have been integral to daily life, but their exploration in catalysis has been rare. Herein, we show a facile and permanent immobilization of organocatalysts on the textile nylon using ultraviolet light. The catalyst and the textile material require no chemical modification for the immobilization. All of the prepared textile-immobilized organocatalysts (a Lewis basic, a Brønsted acidic, and a chiral organocatalyst) display excellent stability, activity, and recyclability for various organic transformations. Very good enantioselectivity (95:5 enantiomeric ratio) can be maintained for more than 250 cycles of asymmetric catalysis. Practical and straightforward applications of textile organocatalysis may be beneficial for various fields by offering inexpensive and accessible functionalized catalytic materials.