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At the end of the 1940s, the production of plastics began on a large scale. Since then, a dynamic increase in their production has been observed. It is associated with a variety of applications and low costs. The negative consequences of the use of polymers and poor disposal are still growing. Microplastic is an important hazard. These are pieces of plastic, the size of which does not exceed 5 mm. Microplastic particles have already been detected all over the world. Increasingly, attention is being paid to their accumulation in the environment. During their stay in ecosystems, they undergo aging processes. Their structure and composition are changing. The washed substances are released into the environment. The aim of the research was to check the effect of artificial aging methods on the leaching of functional groups and changes in the structure of selected polymers. Polystyrene and polyethylene terephthalate were selected for the research. They belong to the most common kind of plastics. For aging, combined methods were used, with irradiation with UV lamp irradiation and hydrogen peroxide. Before and post-aging polymers were analyzed using spectroscopic methods and a microscope. ATR FTIR, Raman confocal microscope and FTIR microscope were used for this purpose. The tests showed leaching of organic products from the samples and the formation of additional bands. The structure of plastics has changed. These changes show a possible degradation path for plastics with a significant environmental impact.

Aluminum doped titania samples were synthesized as supports of copper oxide catalysts for NO reduction with ammonia. Samples were prepared by the sol-gel method with various ratios of aluminum to titanium. Their thermal stability was examined by TG/DSC methods which revealed that precursors were decomposed at 450 °C. The XRD measurements showed that aluminum caused the diminishing of titania crystallites and was built into the anatase structure or formed an amorphous phase. The admixture of aluminum in titania resulted in a significant increase in specific surface area of mesoporous supports as determined by low temperature sorption of nitrogen. Results of the catalytic tests over copper/aluminum-titania samples obtained by impregnation pointed out that the addition of aluminum broadened the temperature window of high catalytic activity. The increase in Al concentration shifted the temperature of maximum activity to higher values, and at the same time lowered nitrous oxide formation as well. Better catalytic efficiency could result from high copper dispersion on the catalysts surface, as well as the synergistic interaction between Ti and Cu causing reduction in CuO species as confirmed by XPS measurements. It was shown that copper was present as Cu+ species mainly, forming Cu-O-Ti bonds on the catalysts surface.

Activated carbon was oxidised with concentrated nitric acid and impregnated with urea to form nitrogen-containing groups. Such a support was impregnated with cobalt, copper or silver nitrates to obtain catalysts for the selective catalytic reduction of nitrogen oxides with ammonia. Infrared spectra confirmed the formation of carboxylic and other organic oxygen-containing groups during oxidation. Nitrogen-containing species resulted from urea thermal decomposition. The metal-containing samples were hydrophilic. Cobalt and copper were present in the samples as small Co3O4 and CuO crystallites, while silver occurred in the form of large metallic crystallites, as seen from the X-ray diffraction patterns. Low temperature N2 sorption revealed that all samples were microporous solids, and the chemical and thermal treatment did not change their textural properties. The copper admixture caused the highest NO conversion, but worsened the selectivity and thermal stability of functionalised carbon support.

At the end of the 1940s, mass production of plastics began. Since then, due to the very wide range of applications, a steady increase in their production has been observed. Anthropogenic activities have a significant impact on the natural environment. In this case, despite the knowledge of the problem, as early as the early 1970s, the harmful consequences continued to increase, and even if stopped immediately, their effects would last for centuries. In 2018, global production of plastics reached almost 360 million tonnes. The diverse use of plastics and low production costs mean that there are no other environmentally friendly alternatives that could replace them on a large scale. Therefore, it can be assumed that their production will continue to grow dynamically. The main hazard posed by the production of plastics is microplastic. These are plastic particles smaller than 5 mm. Research on microplastics in the environment is based mainly on diagnosing the problem in sea waters. Its concentration in soils is underestimated. The microparticles of plastics contained in the soil influence not only its structure or the ability to retain water, but also the organisms living in it. In the experiment, soil samples from the vicinity of a busy road in the city of Krakow, Poland, were examined. First, the samples were separated by density, and then the organic material was digested. The separated microplastics were analyzed both in terms of quantity and quality. Tests were carried out under the FTIR microscope, using the sensitive DRIFT method, and in the case of larger fragments, using ATR-FTIR. The results indicated the presence of a large fraction of microplastics, most often from tire abrasion.

Cu-Ce(Mn)-Al oxide catalysts to NO removal in the broad temperature range were synthesized and tested. The precursor of copper aluminium spinel was obtained with the coprecipitation method. By this method, Cu&ndash, Al spinels with various amounts of manganese and cerium were synthesized as well. These oxides crystallized in the structure of inverse spinel, however, Ce doping caused the appearance of additional CeO2 phase as determined by XRD. The samples were mesoporous solids with moderate surface area and porosity measured by low temperature sorption of nitrogen. The addition of another metal to Cu&ndash, Al spinel caused an increase of activity in selective catalytic reduction of nitrogen oxide with ammonia. The presence of manganese caused the formation of a higher amount of N2O by-product. The catalytic activity increased with the cerium concentration. For the sample with the atomic ratio Ce0.15Cu0.18, ca. 90% of NO conversion was registered between 200 and 350 &deg, C. As examined with XPS spectroscopy, such conversion was attained due to the good dispersion of copper on the catalyst surface. This copper was placed mainly in spinel octahedral positions which enable its easier reduction. The spinel structure causes the presence of cerium as the trivalent cation important in redox cycles with the participation of copper.

The mechanism of thermal degradation of poly(furfuryl alcohol) (PFA) deposited on the MCM-48 mesoporous silica was studied. The behaviour of the thin PFA film homogeneously dispersed on the silica surface (the material with the real PFA/MCM-48 mass ratio of 0.06) was compared to that of the 3D structure of PFA completely filling the MCM-48 channels (the material with the real PFA/MCM-48 mass ratio of 1.02). The progress of decomposition was controlled by thermogravimetry accompanied by infrared spectroscopy providing information on the composition of gaseous products evolved during the sample degradation. The thermal treatment of PFA/MCM-48 composites at various temperatures in the range of 523–1323 K enabled us to synthesize two series of PFA-derived carbon adsorbents: (1) containing the degraded PFA film supported on the mesoporous silica and (2) CMK-1 type carbon replicas, which were obtained by leaching of SiO2 from the PFA/MCM-48 composite after the previous pyrolysis. The structural and textural properties of these materials were determined by powder X-ray diffraction, DRIFT spectroscopy and low-temperature nitrogen adsorption. Furthermore, the samples were tested as adsorbents of different volatile organic compounds (VOCs). The PFA/MCM-48 materials showed the high adsorption capacity only in the removal of polar molecules, whereas CMK-1 was effective in the elimination of linear alkanes and aromatic VOCs as well.

The goal of the study was to modify activated carbon (AC) with nitrogen groups and ceria and to test the obtained materials in low temperature selective catalytic reduction of nitrogen oxides. For that purpose, the starting AC was oxidized with HNO3 of various concentrations, modified with urea and doped with 0.5 wt.% of Ce. It was observed that the increased concentration of acid influenced the catalytic activity, since textural and surface chemistry of activated carbon was changed. The most active sample was that modified with 14 M HNO3 and it reached 96% of NO conversion at 300 &deg, C. Additionally, the addition of Ce improved the catalytic performance of modified AC, and NO was reduced according to oxidation&ndash, reduction mechanism, characteristic for supported metal oxides. Nevertheless, the samples promoted with Ce emitted significantly higher amount of CO2 comparing to the non-promoted ones.

A series of materials based on activated carbon (AC) with copper deposited in various amounts were prepared using an incipient wetness impregnation method and tested as catalysts for selective catalytic reduction of nitrogen oxides with ammonia. The samples were poisoned with SO2 and regenerated in order to analyze their susceptibility to deactivation by the harmful component of exhaust gas. NO conversion over the fresh catalyst doped with 10 wt.% of Cu reached 81% of NO conversion at 140 &deg, C and about 90% in the temperature range of 260&ndash, 300 &deg, C. The rate of poisoning with SO2 was dependent on Cu loading, but in general, it lowered NO conversion due to the formation of (NH4)2SO4 deposits that blocked the active sites of the catalysts. After regeneration, the catalytic activity of the materials was restored and NO conversion exceeded 70% for all of the samples.

A synthesis of metal oxide modified clays based on the hydrogel template assisted route was proposed. This novel method was verified by an intercalation of poly(acrylic acid) (PAA) into the interlayer space of montmorillonite (MT) using the in situ polymerization technique. The obtained hydrogel/clay composite with a MT/PAA mass ratio close to 1.0 exhibited an expanded layered structure and an excellent adsorption capacity for transition metal cations. These features were exploited to the modification of MT-PAA material with various amounts of Fe3+ cations by deposition at controlled pH = 2.5. The introduced Fe species favored the hydrogel burning, therefore in a subsequent step the organic template could be easily removed by calcination under oxidizing conditions at temperature protecting the clay against deep dehydroxylation. A gradual delamination of MT with an increase in the Fe content was observed after thermal treatment. This effect resulted in opening of the MT structure, manifested by a relatively high surface area and a large porosity. XRD, TEM, UV–Vis-DRS and XPS measurements exhibited that the formed α-Fe2O3 nanoparticles were highly dispersed on the exfoliated clay, which comprised a framework stabilizing the nanophase.

Copper–aluminum containing precursors with various Cu/Al molar ratios (from 0.32–1.28) were prepared by co-precipitation in the presence of ammonium carbonate. The thermal stability of the obtained materials was investigated by thermal analysis, which revealed three crucial decomposition steps, finally resulting in the formation of mixed Cu–Al oxides. The changes in structure and texture of the samples at each decomposition step were examined by X-ray diffraction (XRD), diffuse reflectance UV–vis spectroscopy (UV–vis-DRS) and low temperature sorption of nitrogen. It was found that the entire removal of structural carbonates requires a calcination temperature as high as 900 °C. The samples after thermal treatment at this temperature varied in the phase composition of the bulk (determined by XRD) as well as of the surface (determined by X-ray photoelectron spectroscopy). All samples contained the CuAl 2 O 4 phase. Furthermore, an increase in Cu content led to the appearance of an increasing amount of CuO. Copper oxide in the form of relatively small crystallites turned out to be the catalytically active phase in the total oxidation of toluene.

Poly(sodium acrylate), polyacrylamide and their copolymers were introduced into the interlayer spaces of raw montmorillonite (Mt) by in-situ polymerization. The obtained clay polymer nanocomposites (CPN) retained the layered structure. The polymers were intercalated at an intended polymer-to-clay mass ratio of 1:1. Differences in the mechanism of decomposition of samples depended on the type of polymer functional groups. The CPN were tested as adsorbents of Fe3 + ions. The highest adsorption capacity was achieved for samples containing poly(sodium acrylate), which was due to their high swelling capacity and the attraction of iron ions by carboxyl groups.

A series of hydrotalcite-like materials containing Mg 2+ /Zn 2+ and Al 3+ cations in the brucite-like sheets and carbonate or benzoate anions in the interlayer gallery was prepared by the coprecipitation method. The difference in the chemical composition of the synthesized layered double hydroxides resulted in obtaining mixed metal oxides with various phase composition (caused by different cations) as well as various crystallinity and textural parameters (caused by different anions). The Mg Zn Al oxide systems obtained from the benzoate-intercalated precursors had significantly higher crystallinity and narrower pore size distribution compared to the carbonate-modified samples. The structural and textural prop- erties of the calcined materials influenced their sorption capacities in the chromate removal from an aqueous solution at the optimal pH of 6.0. The most efficient adsorbent was obtained from the calcined magnesium–zinc–aluminum hydrotalcite-like precursor containing interlayer CO 3 2 − anions. This mate- rial exhibited high efficiency in the chromate elimination even in the presence of competitive anions (Cl − or SO 4 2 −).

Hydrotalcite-like compounds (HTlcs) containing cobalt and aluminum (intended Co/Al molar ratio = 3.0) were coprecipitated at 30, 50 and 70 °C. Their crystallinity, which was confirmed by powder X-ray diffraction, increased with the precipitation temperature. Furthermore, HTlcs with various cobalt contents were prepared at 70 °C. Thermogravimetric analysis showed that HTlcs were transformed into stable oxides at 550 °C. The decrease in the crystallite size of the formed spinels with the increase in the precipitation temperature was observed. Low temperature sorption of nitrogen revealed meso-macroporous nature of the oxides with extended interparticle porosity. Aluminum segregated on the samples surface, which contained various amounts of lattice and adsorbed/electrophilic oxygen as detected by X-ray electron spectroscopy. The high ratio of lattice to adsorbed/electrophilic oxygen found for the sample with Co/Al = 3:1 caused that it turned out to be the most efficient catalyst in the total oxidation of toluene (50% conversion at 257 °C).

The aim of this study is to gain information necessary to propose the mechanism of the oxide layers’ formation on the FeCr alloy foil of 0.05 mm thickness as well as to obtain indications about thermal treatment resulting in the relatively uniform adhesive layers. The surface morphology of the oxide layers formed on the foil in the course of its thermal treatment as well as layers’ thickness and element distribution along their cross sections were investigated with scanning electron microscopy and secondary ion mass spectrometry. Observed differences were ascribed to the various orientations of FeCr alloy crystallites.

A nanostructured anatase supported V–O–Mo catalyst with V:Mo:Ti = 1:9:90, obtained by sol–gel method from inorganic substrates, was investigated. The structure of the species formed on the catalyst surface in the course of synthesis was determined and its evolution during oxidation and reduction was studied by the FT Raman spectroscopy. Vanadia-like monolayer islands with some molybdenum atoms substituted for vanadium ones were found to prevail on the surface of the catalyst. Oxidation was revealed to cause monolayer islands to join through monolayer bridges formed by vanadium segregating on the surface. However, reduction of the oxidised catalyst was shown to result in the splitting of the monolayer islands into smaller ones with higher molybdenum content. During the strong reduction irreversible transformation of the vanadia-like surface species into the resembling molybdena ones was observed. © 2004 Elsevier B.V. All rights reserved.

The aim of this paper is to investigate the processes occurring during V-O-W unsupported catalyst formation in order to gain the knowledge necessary to design supported catalysts. Sol-gel synthesis of V-W hydroxo-oxide hydrate (W:V = 9:1) from tungsten and vanadyl isopropoxides is described. The hydrate structure is shown to be related to WO 3 .0.33H 2 O. The role of vanadium in the formation of this structure is discussed. Hydrate dehydration is shown to result in the formation of V-W hydroxo-oxide isostructural with hexagonal WO 3 . Further heating of hydroxy-oxide causes a loss of hydroxy groups accompanied by the formation of V-W oxide bronze isostructural with tetragonal WO 3 . Annealing the bronze in an air atmosphere results in the removal of vanadium from the bronze crystallites as a results of its surface segregation. The formation of the surface vanadia-like species on WO 3 -related crystallites is found to be a result of vanadium segregation. Increasing the annealing temperature causes recrystallisation of the surface species. The synthesis of a V-W/TiO 2 oxide catalyst via a mixed oxide formation in the presence of titania sols followed, by surface vanadium segregation in an air containing atmosphere, is proposed. The application of the knowledge gained during our investigation of the formation of the unsupported V-O-W catalyst to the discussion of the morphology of the V-O-W/Ti(Sn)O 2 (rutile) catalyst is also demonstrated.

Yttria-stabilized zirconia (YSZ) was obtained by the coprecipitation at pH 9.0 and by the sol–gel method. These oxide systems crystallized in the tetragonal phase which was revealed by powder X-ray diffraction (XRD). The YSZ supports were mesoporous solids with different kinds of porosity and various BET specific surface areas determined by low-temperature sorption of nitrogen. The incipient wetness technique was used to modify these materials with different amounts of Cu (2.5, 5.0 and 7.5 wt%). The changes in structural and textural properties of the YSZ supports after the CuO introduction were discussed, and the surface composition of the Cu-loaded samples was studied by X-ray photoelectron spectroscopy (XPS). It was found that the intra- and interparticle porosity influences the dispersion of CuO active phase, which is the parameter determining the catalytic activity in the toluene combustion. The material based on coprecipitated YSZ containing 5 wt% of Cu turned out to be the most active catalyst with T50 = 264 °C and the total conversion of toluene observed at 350 °C.

The SCR of NO and NO decomposition were investigated over a V-W-O/Ti(Sn)O 2 catalyst on a Cr-Al steel monolith. The conversions of NO and NH 3 over the reduced and oxidised catalysts were determined. The higher conversion of NO than of NH 3 was observed in SCR over the reduced catalyst and very close conversions of both substrates were found over the oxidised one. The increase of the pre-reduction temperature was found to cause an increase in catalyst activity and its stability in direct NO decomposition. The surface tungsten cations substituted for vanadium ones in vanadia-like active species are considered to be responsible for the direct NO decomposition. The results of DFT calculations for the 10-pyramidal clusters: V 10 O 31 H 12 (V-V) and V 9 WO 31 H 12 (V-W) modelling (001) surfaces of vanadia and WO 3 -V 2 O 5 solid solution (s.s.) active species, respectively, show that preferable conditions for NO adsorption exist on W sites of s.s. species and that reduction causes an increase in their ability for electron back donation to the adsorbed molecule. Electron back donation is believed to be responsible for the electron structure reorganisation in the adsorbed NO molecule resulting in its decomposition. The high selectivity of NO decomposition to dinitrogen was considered to be connected with the formation of the tungsten nitrosyl complexes solely via the W-N bond.

This paper concerns species of WO 3 –V 2 O 5 solid solution and of vanadia–tungsta intermediate compound (IC) formed as a result of oxidation-induced vanadium segregation on the surface of an unsupported V–W–O catalyst. The evolution of the surface species during their interaction with ammonia (64 Torr) and nitric oxide (64 Torr) at room temperature was investigated by FT–Raman spectroscopy. The transformation of WO 3 –V 2 O 5 solid solution species into ammonium methavanadate (V) ones and the reduction of intermediate compound species, followed by inward vanadium diffusion into subsurface layers, were observed as a result of the catalyst interaction with ammonia. The next catalyst interaction with NO was found to cause restoration of the WO 3 –V 2 O 5 species but not of the intermediate compound ones at the surface.

Vanadia-related species formed as a result of vanadium segregation at the surface of V–W oxide bronze crystallites were investigated. The structures of these species and their transformations induced by oxygen removal and oxygen adsorption were monitored using photoelectron spectroscopy and the FT Raman technique. Assignments of the MeO vibrational bands, based on the results of DFT calculations for model clusters, have been proposed. Two kinds of surface species are dominant depending on the tungsten content: V 4+ –O–W 6+ at low tungsten content and V 5+ –O–W 5+ at higher tungsten concentration.

This paper concerns the relation between surface structure of crystalline vanadia-like active species on vanadia–tungsta catalyst and their activity in the selective reduction of NO by ammonia to nitrogen. The investigations were performed for Ti–Sn-rutile-supported isopropoxy-derived catalyst. The SCR activity and surface species structure were determined for the freshly prepared catalyst, for the catalyst previously used in NO reduction by ammonia (320 ppm NO, 335 ppm NH3 and 2.35 vol% O2) at 573 K as well as for the catalyst previously annealed at 573 K in helium stream containing 2.35 vol% O2. The crystalline islands, exposing main V2O5 surface, with some tungsten atoms substituted for V-ones, were found, with XPS and FT Raman spectroscopy, to be present at the surface of the freshly prepared catalyst. A profound evolution of the active species during the catalyst use at 573 K was observed. Dissociative water adsorption on V5+OW6+ sites is discussed as mainly responsible for the catalyst activity at 473 K and that on both V5+OW6+ and V4+OW6+ sites as determining the activity at 523 K.

Powder X-ray diffraction, Fourier transform Raman spectroscopy, solid-state NMR and X-ray photoelectron spectroscopy were used to determine the composition and structure of a mixed oxide containing 10 mol% V2O5 and 90 mol% WO3. The parent sample consists of hybrid crystallites of a tungsta-bronze isostructural with tetragonal WO3 but containing atomic vanadium in the bulk of the crystals and V(III) in the surface region, and of small crystals of strongly reduced vanadia-like surface species (V2O5–x with x=0.42). Further thermal treatment causes progressive surface segregation of vanadium from the V2O5–WO3 solid solution, accompanied by the formation of a WO3–V2O5 solid solution and partial tetragonal–monoclinic structural transformation of the bronze.

Poly(acrylic acid)/montmorillonite (MMT) composites with various polymer contents were synthesized by in situ polymerization technique. The structure of obtained materials was characterized by powder X-ray dif- fraction and infrared spectroscopy (FTIR). It was found that only a limited amount of hydrogel could be introduced between the clay layers. The remaining part of polymer was deposited on the external surface of clay particles. The introduction of the polymer modifier significantly increased the adsorption capacity of MMT in the elimination of $Fe^{3+}$ ions from aqueous solution. The thermal behavior of the samples before and after the $Fe^{3+}$ adsorption was examined by thermogravimetry and differential thermal analysis. Moreover, the composition of gaseous products evolved during decomposition was determined by FTIR. The mate- rials after $Fe^{3+}$ adsorption exhibited different thermal sta- bility in oxidizing atmosphere than the fresh samples. $Fe^{3+}$ cations, forming $FeO_x$ species during thermal treatment, appeared to be effective catalysts of polymer oxidation.

The increased interest in arguments for the existence of God appeared in the XI century, with the development of the dialectic. One of the most famous ontological proof is a proof of Anselm of Canterbury – to prove the existence of God by going out only with HIS idea. In the XIII century, the ontological argument has lost its importance to the „five ways” of the Saint Thomas Aquinas, inspired by Aristotle and based on experience.

Highly crystalline mixed cobalt– and copper–aluminium oxides were obtained from coprecipitated precursors. These Co–Al and Cu–Al oxide systems appeared to be active catalysts of the total oxidation of toluene in the temperature range of 250–450 °C. The study on chemical and phase composition, thermal stability, texture and reducibility of the synthesized samples allowed to identify their active phases in toluene combustion.

Polymer/layered silicate nanocomposites based on polymeric quaternary ammonium salts (ionenes) intercalated into the interlayer galleries of montmorillonite were synthesized. Zeta potential measurements were conducted to determine the amount of ionenes required to neutralize the negative charge of clay. The composition and structure of the obtained nanocomposites were examined by elemental analysis, ATR-FTIR and XRD. High dye sorption capacity was observed for the composite containing ionene 6,2.

The FeCrAl-alloy foils of 0.1 and 0.05 mm thickness, being the supports of metallic monolithic environmental catalysts, were investigated by XRD and TEM to determine the reasons of the differences in morphology of the alumina adhesive layers grown during oxidation. Alumina adhesive layers of stable thickness and outgrowing scale-like crystallites were observed on 0.1 mm foil and alumina layers of different thickness with lower population of outgrowing scale-like crystallites on 0.05 mm foil. αFe was found to be the only phase seen by XRD in both kinds of the foil. The density of dislocations on the surface of 0.1 mm foil was found to be of one order of magnitude higher than this on the surface of the 0.05 mm one. Both kinds of the foil reveal different texturing investigated with X-ray. Different texturing connected with various face development results in various possibilities of growing Al2O3 layers. However, the high dislocation density is responsible for the high population of scale-like crystallites on 0.1 mm foil.