Adsorption of Fluoxetine and Venlafaxine onto the Marine Seaweed Bifurcaria bifurcata

Marine macroalga Bifurcaria bifurcata was investigated as sorbent for two environmental emerging pollutants, the pharmaceuticals venlafaxine (VLF) and fluoxetine (FLX), from aqueous solutions, both in mono and bicomponent batch systems. The alga was characterized by means of IR spectroscopy, allowing to identify the most important groups for biosorption, carboxylic, sulfonic and hidroxile. The point of zero charge was determined, being 6.4. Adsorption of FLX follows a pseudo first order kinetics and kinetic constants are higher for FLX than for VLF. Its adsorption better represented by the pseudo second order model. For both pharmaceuticals, the equilibrium was reached within *100 min. Adsorption studies reveal that the process was more efficient at lower pH range and followed the Langmuir–Freundlich’s model for VLF and Langmuir’s model for FLX. Maximum adsorption capacities reached a level of 12 – 3 and 22 – 4 lmol/g for VLF and FLX, respectively, in the mono-component system. The difference was attributed to the presence of various functional groups of varying polarity within the adsorbates’ molecules that affected their interactions with the adsorbent surface. The Langmuir–Freundlich’s extended model was applied to the adsorption data of the bicomponent system and no changes in the maximum adsorption capacities were found (14 – 2 and 20 – 3 lmol/g for VLF and FLX, respectively), there is no evidence of competition between the adsorbates.Acknowledgments are due to Fundac¸a˜o para a Cieˆncia e a Tecnologia (FCT), FEDER under Programme PT2020 (Project UID/QUI/50006/2013—POCI/01/0145/FEDER/ 007265) and Programme FCT–UT Austin, Emerging Technologies (Project UTAP-ICDT/CTM-NAN/0025/2014) for the financial funding. The authors would like to thank the EU and FCT/UEFISCDI/FORMAS for funding, in the frame of the collaborative international consortium REWATER financed under the ERA-NET Cofund WaterWorks2015 Call. This ERA-NET is an integral part of the 2016 Joint Activities developed by the Water Challenges for a Changing World Joint Programme Initiative (Water JPI).W.S. also thanks FCT/ MEC for his grant (Laborato´rio Associado para Quı´mica Verde–Tecnologia e Processos Limpos–UID/QUI/50006, POCI-01-0145-FEDER-007265).info:eu-repo/semantics/publishedVersio

Manipulacja: pedagogiczno-społeczne aspekty. Cz. 1, Interdyscyplinarne aspekty manipulacji

Praca recenzowana / peer-reviewed pape

Assessment of degradation of the soil cover along tourist paths in the area of Tarnica pick and Szeroki Wierch in Bieszczadzki National Park.

The environment of Bieszczadzki National Park has been characterized , the main hazards of the nature occurred in the area and the methods of prevention of the degradation have been described. The tourist path leading from Ustrzyki Gorne through Polonina Szerokiego Wierchu to Tarnica peak was the investigated area. The assessment of degradation of the path has been made, damaged path have been photographed and classified according to the 5 degree scale. Chemical pollution of the environment and a sample of soil have been analyzed.The conclusions allowed to state that the prevention methodsare effective, no soil pollution has been found.W pracy scharakteryzowano środowisko przyrodnicze Bieszczadzkiego Parku Narodowego, przedstawiono główne zagrożenia dla przyrody występujące na jego terenie oraz sposobów zapobiegania ich skutkom. Obszarem badań był szlak turystyczny prowadzący z Tarnicy przez Połoninę Szerokiego Wierchudo Ustrzyk Górnych. Dokonano oceny degradacji gleb przy tym szlaku, uszkodzone fragmenty sfotografowano i sklasyfikowanowg pięciostopniowej skali uszkodzeń. Przeanalizowano również stan środowiska Parku pod kątem zanieczyszczenia chemicznego, dokonano analizy chemicznej pobranej próbki gleby. Stwierdzono skuteczność działań ochronnych oraz brak znaczącego zanieczyszczenia chemicznego

Dual-function hydrotalcite-derived adsorbents with sulfur storage properties : dyes and hydrotalcite fate in adsorption-regeneration cycles

Thermal treatment of hydrotalcite at increasing temperatures resulted in formation of mixed oxides that exhibited different adsorption behavior toward anionic and cationic industrial dyes. The material annealed at 450 °C was characterized by the highest maximum adsorption capacity for both types of dyes. The adsorption was strongly pH dependent and for the anionic dye abatement low pH was favored whilst higher pH was more preferable for removal of the cationic dye. According to the equilibrium experiments, the maximum adsorption capacity increased from 179 ± 5 to 291 ± 8 mg g−1 in case of the anionic dye at pH 3.5 and from 6 ± 2 to 48 ± 2 mg g−1 in case of the cationic dye at pH 8.0, on starting and thermally treated material at 450 °C, respectively. Detailed characteristics of spent adsorbent and its reconstructed form revealed that after each cycle of adsorption and thermal regeneration the maximum adsorption capacity of the material decreased due to changes in the structure and accumulation of sulfur compounds. Evolution of specific surface area and porosity was correlated with annealing temperatures and behavior of dye's residues.info:eu-repo/semantics/publishedVersio

Interaction between adsorbed molecules and tailor made large chelating ligands grafted on SBA-15 studied by means of thermoporometry

Modified mesoporous silicas were examined as adsorbents for efficient removal of model pollutants from wastewaters. Functionalized SBA-15 materials for capture of cationic pollutants such as metal cations and anionic dyes were obtained using post-synthesis grafting method. Large organic ligands containing acetyloacetone, 2-aminopyridine, 2-aminothiazole and 2-aminobenzothiazole groups were incorporated into the adsorbents' structure. The adsorption capacities reached levels of 38.6, 43.1, 64.3, 68.6 and 88.9 mg g−1 for Cu2+, Rose Bengal, Congo Red, Levafix Amber CA gran and Methyl Orange, respectively. Moreover, the adsorption efficiency depended on a type of the model molecule and a type of the surface chelating group. The pores' size and the pores' volume of the hybrid materials before and after adsorption was determined in hydrated state using thermoporometry. For the first time, by means of this methodology, it was possible to propose a model of interactions between the adsorbed molecules and the grafted organosilanes. Adsorption of organic dyes resulted in most cases in formation of J-aggregates.Part of the research was carried out with the equipment purchased thanks to the financial support of the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program (contract no. POIG.02.01.00-12-023/08) and within the scope of the project of Labóratorio Associado para Química Verde – Technologia e Processos Limpos – UID/QUI/50006, is financed by national founds of FCT/MEC and co-financed by Fundos FEDER (POCI-01-0145-FEDER-007265) within the scope of the partnership agreement PT2020. To all financing sources the authors are greatly indebted.info:eu-repo/semantics/publishedVersio

Sustainable adsorbents formed from by-product of acid activation of vermiculite and leached-vermiculite-LDH hybrids for removal of industrial dyes and metal cations

Hydrotalcite-like layered double hydroxide (LDH) materials were synthesized from liquid waste by-product produced during acid activation of vermiculite (raw (W) and expanded (Ve)), and by combining the waste with the activated mineral, novel hybrid vermiculite-hydrotalcite-like materials were obtained in one-pot synthesis. Batch system adsorption experiments were performed on fresh and calcined (at 450 °C) materials using two anionic dyes (Congo Red - CR, and Reactive Red 184 - R), a cationic dye (Astrazon Red - AR), and Cu2+. Calcination significantly increased the materials' adsorption capacities for all the pollutants. The highest adsorption capacities of the LDH derived from W were 289 ± 2, 137 ± 2, 38.2 ± 0.6 and 64 ± 2 mg g−1, while for the ones derived from Ve were 214 ± 2, 119.5 ± 0.3, 35.9 ± 0.7 and 66 ± 3 mg g−1 for CR, R, AR and Cu2+, respectively. The hybrids obtained from W attained removal levels of 238 ± 3, 111 ± 2, 44 ± 1 and 70 ± 1 mg g−1 and their counterparts derived from Ve reached 84 ± 1, 34.1 ± 0.5, 43 ± 2 and 75 ± 1 mg g−1 for CR, R, AR and Cu2+, respectively. Strong synergic effect on adsorption was observed in the hybrid materials, especially in these derived from Ve. These adsorbents had higher (up to 400%) adsorption capacities than theoretical ones prepared by mixing ex-situ appropriate amounts of activated vermiculite and LDH. All the materials were characterized by XRD, SEM-EDS, and ATR techniques. The proposed procedure is a sustainable approach to clay minerals valorization and my open new possibilities in fields such as wastewater treatment or catalysis.This work, within the scope of the project of Labóratorio Associado para Química Verde – Technologia e Processos Limpos – UID/QUI/50006, is financed by national founds of FCT/MEC and co-financed by Fundos FEDER (POCI-01-0145-FEDER-007265) within the scope of the partnership agreement PT2020. Part of the research was carried out with the equipment purchased thanks to the financial support of the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program (contract no. POIG.02.01.00-12-023/08). To all financing sources the authors are greatly indebted.info:eu-repo/semantics/publishedVersio

Acid-base treated vermiculite as high performance adsorbent : insights into the mechanism of cationic dyes adsorption, regeneration, recyclability and stability studies

Additional treatment with NaOH of acid activated vermiculite results in even higher increase in the adsorption capacity in comparison to samples modified only in acidic solution (first step of activation) with respect to raw material. Optimization of treatment conditions and adsorption capacity for two cationic dyes (methylene blue (MB) and astrazon red (AR)), also as binary mixture, was evaluated. The capacity, based on column studies, increased from 48 ± 2 to 203 ± 4 mg g-1 in the case of methylene blue and from 51 ± 1 to 127 ± 2 mg g-1 in the case of astrazon red on starting and acid-base treated material, respectively. It was shown that adsorption mechanism changes for both cationic dyes after NaOH treatment and it results in decrease of adsorption rate. In binary mixtures methylene blue is bound stronger by adsorbent and astrazon red may be removed in initial stage of adsorption. Extensive studies on desorption/regeneration process proved high efficiency in recyclable use of all materials. Although cation exchange capacity decreases due to acid treatment, after base treatment exchange properties are used more efficiently. On the other hand, increased specific surface area has less significant contribution into the adsorption potential of studied materials. Obtained adsorbents worked efficiently in 7 adsorption-regeneration cycles and loss of adsorption capacity was observed only in two first cycles.info:eu-repo/semantics/publishedVersio

Simultaneous removal of dyes and metal cations using an acid, acid-base and base modified vermiculite as a sustainable and recyclable adsorbent

The aimof thiswork was the modification of vermiculite in order to produce a lowcost, efficient and sustainable adsorbent for dyes and metals. Three activation methods consisting of acid, base and combined acid/base treatment were applied to improve the of vermiculite's adsorption properties. Adsorbents were tested in single, biand tricomponent solutions containing cationic dyes and Cu2+ cations. The rawmaterial showed lowadsorption capacity for dyes and metal. The acid/base treated vermiculite had very good adsorption capacity toward dyes while the maximumadsorption capacity for Cu2+ did not change comparing to the startingmaterial. The alkaline treated vermiculite was a good adsorbent for metals,while still being able to remove dyes on the level of the not treated material. Moreover, it was shown that the materials may be regenerated and used in several adsorptiondesorption cycles. Furthermore, itwas possible to separate adsorbed dyes from metals thatwere desorbed, using as eluents ethanol/NaCl and 0.05MHNO3, respectively. This opens a possibility for sustainable disposal and neutralization of both of the pollutants or for their further applications in other processes.info:eu-repo/semantics/publishedVersio

The influence of acid treatments over vermiculite based material as adsorbent for cationic textile dyestuffs

The influence of different acid treatments over vermiculite was evaluated. Equilibrium, kinetic and column studies have been conducted. The results showed that vermiculite first treated with nitric acid and then with citric acid has higher adsorption capacity, presenting maximum adsorption capacities in column experiments: for Astrazon Red (AR), 100.8 ± 0.8 mg g−1 and 54 ± 1 mg g−1 for modified and raw material, respectively; for Methylene Blue (MB) 150 ± 4 mg g−1 and 55 ± 2 mg g−1 for modified and raw material, respectively. Materials characterization by X-ray diffraction, UV–vis-diffuse reflectance spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, X-ray fluorescence, N2 adsorption and CEC determination, has been performed. The results suggest the existence of exchange of interlayer cations, leaching of metals from vermiculite's sheets and formation of an amorphous phase in the material. Adsorption follows pseudo 2nd order model kinetics for both dyestuffs and equilibrium occurs accordingly to Langmuir's model for AR and Freundlich's model for MB. In column systems Yan's model is the best fit. The enhanced properties of acid treated vermiculite offer new perspectives for the use of this adsorbent in wastewater treatment.info:eu-repo/semantics/publishedVersio