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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Activation of homogeneous and heterogeneous Fenton processes by ultrasound and ultraviolet/visible irradiations for the removal of ibuprofen in water / Activation du procédé Fenton (homogène et hétérogène) par irradiation ultrasonore et rayonnement ultraviolet / visible pour l'élimination de l'ibuprofène dans l'eau

Adityosulindro, Sandyanto 07 April 2017 (has links)
Du fait de sa consommation en plein essor et d’une élimination partielle par les procédés conventionnels de traitement des eaux, l'ibuprofène, un médicament anti-inflammatoire non stéroïdien, a été détecté dans les ressources en eau, suscitant de plus en plus d'inquiétude quant à son impact possible sur l'environnement et la santé. Par ailleurs, les procédés d'oxydation avancée (POA), parmi lesquels la réaction Fenton, ont montré d’excellents résultats pour l'élimination de divers composés organiques. Traditionnellement basé sur l'utilisation du peroxyde d'hydrogène et des ions ferreux en solution, l'application à grande échelle de ce POA est encore limitée par une fenêtre de pH étroite (2 à 4) et une récupération difficile du catalyseur à base de fer. Ce travail a étudié l'oxydation Fenton de l'ibuprofène et l'activation de la réaction par irradiation ultrasonore (US) et rayonnement ultraviolet/visible (UV/Vis) et de manière à abaisser la concentration de fer dissous ou à améliorer l'activité de catalyseurs hétérogènes. A cet effet, on a d'abord évalué l'efficacité des POA individuels homogènes (sonolyse, photolyse, sono- et photo-oxydation avec H2O2, oxydation Fenton), en fonction de paramètres opératoires tels que la longueur d'onde lumineuse et la fréquence ultrasonore. Ensuite, on a examiné leurs combinaisons deux-par-deux et globale (sonophotolyse, oxydation sono-, photo- et sono-photo- Fenton) en mettant l'accent sur l'identification d'effets synergiques. En particulier, les oxydations US/Fenton et Vis/Fenton se sont révélées plus efficaces que la somme des procédés individuels grâce à la sono- et photo-régénération des ions ferreux. Ces résultats ont également servi de référence pour l'évaluation des systèmes hétérogènes. Parmi les solides testés, on a montré qu’une zéolite dopée au fer (de type Fe/ZSM5) était un catalyseur prometteur pour l'oxydation de l'ibuprofène par le peroxyde, en raison d'une efficacité élevée à pH naturel et d’une faible lixiviation du fer. Cependant, dans ce cas, on n’a observé au mieux qu'une addition d’effets des ultrasons ou de la lumière et de l'oxydation Fenton hétérogène. Outre la conversion du polluant et du carbone organique total (COT), la formation des principaux produits de dégradation a été suivie pour différents procédés et des voies possibles de dégradation ont été proposées. L’effet matrice a également été examiné en utilisant un effluent de station, qui a eu pour conséquence de réduire la performance de tous les procédés d'oxydation, en raison d'un pH tampon alcalin ou de l’atténuation de la lumière. / Due to booming consumption and only partial removal by conventional water treatment processes, ibuprofen, a non-steroidal anti-inflammatory drug, has been detected in water resources, raising increasing concerns for possible environmental and health impact. On the other hand, advanced oxidation processes (AOPs), among which Fenton reaction, have shown successful results forremoval of various organic compounds. Traditionally based on the use of hydrogen peroxide and ferrous ions in solution, large-scale application of this AOP is still limited by narrow pH window (2 to 4) and uneasy recovery of iron catalyst. This work investigated Fenton-based oxidation of ibuprofen, and reaction activation by ultrasound (US) irradiation and ultraviolet/visible light (UV/Vis) so as to lower the required concentration of dissolved iron catalyst or improve the activity of heterogeneous counterparts. To that purpose, the efficacy of individual homogeneous AOPs (sonolysis, photolysis, ultrasound/H2O2, light/H2O2, Fenton oxidation) was evaluated first, varying operating parameters such as light wavelength and ultrasound frequency. Then, their two-by-two and overall combinations (sonophotolysis, sono-Fenton, photo-Fenton and sono-photo-Fenton oxidation) were examined with emphasis on the identification of synergistic effects. In particular, combined US/Fenton and Vis/Fenton oxidation were found more effective than the sum of individualprocesses due to sono- and photo-regeneration of ferrous ions. These results also served as a reference for the assessment of heterogeneous systems. Among tested solids, iron-containing zeolite (Fe-ZSM5 type) was shown to be a promising catalyst for peroxide oxidation of ibuprofen due to high efficiency at natural pH and low iron leaching. However, in this case, no more than additive effects was observed between ultrasound/light irradiation and heterogeneous Fenton oxidation. Beside pollutant and Total Organic Carbon conversion, main degradation products were monitored for different processes and some plausible degradation pathways were proposed. Water matrix impact was also addressed using wastewater plant effluent, which resulted into hindered performance of all oxidation processes either due to alkaline buffer or light attenuation effect.
2

Uticaj fizičko-hemijskih svojstava mikroplastike i odabranih perzistentnih organskih polutanata na interakcije u vodenom matriksu / Impact of physicochemical properties of microplastics and selected persistent organic pollutants on interactions in the aqueous matrix

Lončarski Maja 20 October 2020 (has links)
<p>Mikroplastika&nbsp; je&nbsp; sveprisutna&nbsp; u&nbsp; vodenom&nbsp; ekosistemu&nbsp; pri&nbsp; čemu&nbsp; se&nbsp; često<br />ističe značaj ispitivanja njihovog uticaja na pona&scaron;anje drugih jedinjenja u vodi.<br />Pod pojmom mikroplastika podrazumevaju se plastične čestice manje od 5 mm.<br />Imajući u vidu potrebu za unapređenjem znanja o &scaron;tetnom uticaju mikroplastike<br />u životnoj sredini u ovom radu sproveden je set eksperimenata u kom je ispitivan<br />mehanizam&nbsp; interakcija&nbsp; koje&nbsp; se&nbsp; uspostavljaju&nbsp; prilikom&nbsp; adsorpcije&nbsp; hlorovanih<br />fenola,&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; na mikroplastici&nbsp; u&nbsp; vodenom&nbsp; matriksu.&nbsp; Kako&nbsp; bi&nbsp; se&nbsp; &scaron;to&nbsp; detaljnije&nbsp; razumeo&nbsp; uticaj mikroplastike&nbsp; i&nbsp; osobina&nbsp; vodenog&nbsp; matriksa&nbsp; na&nbsp; pona&scaron;anje&nbsp; organskih&nbsp; polutanata, laboratorijska ispitivanja su sprovedena u sintetičkom i realnom vodenommatriksu.&nbsp; Takođe&nbsp; je&nbsp; sprovedena&nbsp; optimizacija&nbsp; izolovanja&nbsp; i&nbsp; karakterizacije mikroplastike iz kozmetičkih sredstava u cilju procene uticaja osobina primarne mikroplastike na uspostavljanje interakcija sa organskim polutantima. Na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata&nbsp; istraživanja&nbsp; može&nbsp; se&nbsp; zaključiti&nbsp; da&nbsp; se optimalna metoda izolovanja mikroplastike iz kozmetičkih sredstava zasniva na dodatnom&nbsp; tretiranju&nbsp; osu&scaron;enog&nbsp; materijala&nbsp; 30%&nbsp; vodonik-peroksidom,&nbsp; nakon ekstrakcije&nbsp; sredstva&nbsp; u&nbsp; destilovanoj&nbsp; vodi,&nbsp; u&nbsp; cilju&nbsp; dobijanja&nbsp; čistijih&nbsp; uzoraka mikroplastike. Promena brzine me&scaron;anja ima znčajan uticaj na promenu stepena adsorpcije ispitivanih grupa organskih jedinjenja.&nbsp; Uticaj se ogleda u povećanju stepena adsorpcije sa porastom brzine me&scaron;anja, a maksimalni procenat adsorpcije postignut&nbsp; je&nbsp; pri&nbsp; brzini&nbsp; me&scaron;anja&nbsp; od&nbsp; 150&nbsp; o/min.&nbsp; Dodatno,&nbsp; disperzija&nbsp; pra&scaron;kastih materijala u vodi nema značajan uticaj na promenu stepena adsorpcije hlorovanih fenola,&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; na mikroplastici.Ravnotežno&nbsp; stanje&nbsp; između&nbsp; koncentracije&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata<br />benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; u&nbsp; vodi&nbsp; i&nbsp; odabranih predstavnika&nbsp; mikroplastike&nbsp; (PEp,&nbsp; PE_PCPs_1,&nbsp; PE_PCPs_2,&nbsp; PEg,&nbsp; PET,&nbsp; PP&nbsp; i PLA) uspostavlja se nakon 24 i 48 h kontakta u zavisnosti od vrste jedinjenja. Na promenu&nbsp; adsorpcionog&nbsp; afiniteta&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata&nbsp; benzena&nbsp; i policikličnih aromatičnih ugljovodonika prema mikroplastici utiču kako fizičkohemijske&nbsp; osobine&nbsp; jedinjenja&nbsp; tako&nbsp; i&nbsp; karakteristike&nbsp; mikroplastike.&nbsp; Na&nbsp; osnovu kinetičkih&nbsp; eksperimenata, najveći adsorpcioni afinitet ka mikroplastici&nbsp; ispoljili su&nbsp; derivati&nbsp; benzena&nbsp; (qt=103-350&nbsp; &micro;g/g),&nbsp; dok&nbsp; je&nbsp; najmanji&nbsp; uočen&nbsp; kod&nbsp; hlorovanih fenola&nbsp; (qt=25-225&nbsp; &micro;g/g).&nbsp; Dobijeni&nbsp; rezultati&nbsp; adsorpcije&nbsp; derivata&nbsp; benzena&nbsp; na ispitivanim&nbsp; česticama&nbsp; mikroplastike&nbsp; takođe&nbsp; su&nbsp; ukazali&nbsp; na&nbsp; veći&nbsp; afinitet&nbsp; ovih jedinjenja&nbsp; ka&nbsp; mikroplastici,&nbsp; u&nbsp; poređenju&nbsp; sa&nbsp; jedinjenjima&nbsp; iz&nbsp; grupe&nbsp; policikličnih aromatičnih&nbsp; ugljovodonika&nbsp; i&nbsp; hlorovanih&nbsp; fenola&nbsp; sličnih&nbsp; logKow&nbsp; vrednosti. Dodatno,&nbsp; uticaj&nbsp; vodenog&nbsp; matriksa&nbsp; na&nbsp; adsorpciju&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata benzena&nbsp; i&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika&nbsp; na&nbsp; mikroplastici&nbsp; zavisi&nbsp; od same grupe jedinjenja kao i od vrste mikroplastike pri čemu je najmanje izražen u&nbsp; slučaju&nbsp; ispitivanih&nbsp; policikličnih&nbsp; aromatičnih&nbsp; ugljovodonika,&nbsp; a&nbsp; najvi&scaron;e&nbsp; kod hlorovanih fenola.Visoke&nbsp; vrednosti&nbsp; koeficijenta&nbsp; determinacije&nbsp; kinetičkog&nbsp; modela&nbsp; pseudodrugog&nbsp; reda&nbsp; za&nbsp; adsorpciju&nbsp; hlorovanih&nbsp; fenola,&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; policikličnih aromatičnih ugljovodonika na čestice mikroplastike ukazjuju da je hemisorpcija mogući&nbsp; mehanizam.&nbsp; Pored&nbsp; visokih&nbsp; vrednosti&nbsp; koeficijenata&nbsp; determinacije&nbsp; u slučaju svih odabranih organskih jedninjenja dobijena konstanta brzine drugog reda&nbsp; bila&nbsp; je&nbsp; manja&nbsp; od&nbsp; po četne&nbsp; brzine&nbsp; adsorpcije&nbsp; &scaron;to&nbsp; ukazuje&nbsp; na&nbsp; znatno&nbsp; brže odvijanje&nbsp; adsorpcije&nbsp; pri&nbsp; kraćim&nbsp; vremenima&nbsp; kontakta&nbsp; (12-24&nbsp; h)&nbsp; nakon&nbsp; čega&nbsp; je<br />dolazilo do usporavanja procesa adsorpcije.Mehanizam adsorpcije hlorovanih fenola, derivata benzena i policikličnih aromatičnih ugljovodonika&nbsp; ispitivan&nbsp; je primenom Freundlich-ovog, Langmuirovog,&nbsp; Redlich-Peterson-ovog&nbsp; i&nbsp; Dubinine-Radusckevich-evog&nbsp; adsorpcionog modela. Vrednosti Freundlich-ovog eksponenta za adsorpciju hlorovanih fenola, derivata benzena i&nbsp; policikličnih aromatičnih ugljovodonika bile su manje od 1,<br />&scaron;to ukazuje na to da je slobodna energije adsorpcije na mikroplastci opadala sa povećanjem&nbsp; inicijalne&nbsp; koncetracije&nbsp; ispitivanih&nbsp; polutanata.&nbsp; Vrednosti maksimalnog adsorpcionog kapaciteta dobijene za&nbsp; adsorpcione procese PAH&nbsp; na česticama mikroplastike bile su u opsegu od 29,7-2596,5 &micro;g/g. Visoke vrednosti maksimalnih adsorpcionih kapaciteta dobijene su takođe za adsorpciju derivata benzena na ispitivanim vrstama mikroplastike&nbsp; 39,3-2010,1 &micro;g/g. S druge strane, uočeno&nbsp; je&nbsp; različito&nbsp; adsorpciono&nbsp; pon&scaron;anje&nbsp; hlorovanih&nbsp; fenola&nbsp; u&nbsp; zavisnosti&nbsp; od vodenog metriksa u kom su eksperimenti sprovedeni pri čemu su&nbsp; qmax&nbsp; vrednosti iznosile 20,00-205,6 &micro;g/g. Značajan uticaj&nbsp; pH vrednosti vodenog matriksa&nbsp; utvrđen je&nbsp; za adsorpciju hlorovanih&nbsp; fenola&nbsp; na&nbsp; mikroplastici,&nbsp; dok&nbsp; u&nbsp; slučaju&nbsp; derivata&nbsp; benzena&nbsp; i&nbsp; PAH promena pH vrednosti vodenog matriksa nije pokazala značajan uticaj. Rezultati dobijeni&nbsp; za&nbsp; adsorpciju&nbsp; hlorovanih&nbsp; fenola&nbsp; na&nbsp; mikroplastici&nbsp; ukazuju&nbsp; na&nbsp; nižu tendenciju&nbsp; ka&nbsp; formiranju&nbsp; interakcija&nbsp; hlorovanih&nbsp; fenola&nbsp; sa&nbsp; česticama mikroplastike pri pH 4 i pH 10, pri čemu se stepen adsorpcije kretao u opsegu od 8-35% i 15-35%, respektivno, u odnosu na pH 7 (55-65%). Najniži&nbsp; adsorpcioni&nbsp; afinitet&nbsp; uočava&nbsp; se&nbsp; pri&nbsp; adsorpciji&nbsp; ispitivanih&nbsp; grupa jedinjenja na PLA. Može se pretpostaviti da će se organski polutanti,&nbsp;&nbsp; ukoliko ova vrsta mikroplastike dospe u vodene sisteme, slabo vezivati na ovaj materijal pri čemu će značajno manje uticati na njihov trasport kroz životnu sredinu, u odnosu<br />na druge ispitivane vrste mikroplastike. Na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata&nbsp; istraživanja&nbsp; može&nbsp; se&nbsp; zaključiti&nbsp; da&nbsp; na adsorpciju ispitivanih grupa organskih jedinjenja i mikroplastike značajan uticaj imaju&nbsp; fizičko-hemijske&nbsp; osobine&nbsp; ispitivanih&nbsp; jedinjenja&nbsp; kao&nbsp; &scaron;to&nbsp; su&nbsp; kiselinska konstanta, veličina molekula, hidrofobnost, stukturni raspored i dr. Pored toga, karakteristike vodenog matriksa, među kojima je najvažnija pH vrednost, imaju značajan&nbsp; uticaj&nbsp; na&nbsp; adsorpcioni&nbsp; afinitet&nbsp; jedinjenja&nbsp; ka&nbsp; mikroplastici.&nbsp; Dodatno,<br />struktura&nbsp; i&nbsp; poreklo&nbsp; polimera&nbsp; ima&nbsp; veliki&nbsp; uticaj&nbsp; na&nbsp; formiranje&nbsp; interakcija&nbsp; sa<br />ispitivanim grupama organskih polutanata. Dobijeni rezultati takođe ukazuju na<br />nemogućnost&nbsp; određivanje&nbsp; unifomnog&nbsp; mehanizma&nbsp; adsorpcije&nbsp; organskih<br />jedinjenja na česticama mikroplastike u vodi.</p> / <p>Microplastics&nbsp; are&nbsp; ubiquitous&nbsp; in&nbsp; aquatic&nbsp; ecosystems,&nbsp; so&nbsp; it&nbsp; is&nbsp; essential&nbsp; to study their&nbsp; impact on the behaviour of other compounds which are commonly present in water. The term microplastics refers to all plastic particles smaller than 5 mm. In order&nbsp; to address knowledge gaps relating to the potential harmful effects of microplastics in the environment, the experiments conducted during this thesis were designed to investigate the adsorption mechanism of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastics in water.&nbsp; To&nbsp; provide&nbsp; a&nbsp; more&nbsp; detailed&nbsp; understanding&nbsp; of&nbsp; the&nbsp; influence&nbsp; of&nbsp; different water&nbsp; matrices&nbsp; on&nbsp; adsorption&nbsp; properties&nbsp; of&nbsp; microplastics,&nbsp; experiments&nbsp; were conducted in both synthetic and real water matrices. In the course of this work, methods were optimised for the isolation and characterization of microplastifrom personal care products, in order to allow investigation&nbsp; of the influence of the&nbsp; properties&nbsp; of&nbsp; primary&nbsp; microplastics&nbsp; on&nbsp; their&nbsp; interactions&nbsp; with&nbsp; organic pollutants.Base on the obtained results, it can be concluded that the optimal method of isolating microplastics from personal care products is based&nbsp; on treating already dried&nbsp; material&nbsp; with&nbsp; 30%&nbsp; hydrogen&nbsp; peroxide,&nbsp; after&nbsp; extraction&nbsp; of&nbsp; the&nbsp; agent&nbsp; in distilled water, in order to obtain cleaner microplastic samples. The mixing rate was&nbsp; found&nbsp; to&nbsp; have&nbsp; a&nbsp; significant&nbsp; effect&nbsp; on&nbsp; the&nbsp; degree&nbsp; of&nbsp; adsorption&nbsp; of&nbsp; the investigated&nbsp; organic&nbsp; compounds.&nbsp; Increasing&nbsp; the&nbsp; mixing&nbsp; speed&nbsp; led&nbsp; to&nbsp; a&nbsp; higher<br />degree&nbsp; of&nbsp; adsorption,&nbsp; with&nbsp; the&nbsp; maximum&nbsp; adsorption&nbsp; percentage&nbsp; reached&nbsp; at&nbsp; a<br />mixing speed of 150 rpm. In addition, the dispersion of powdered materials in the&nbsp; water&nbsp; had&nbsp; no&nbsp; significant&nbsp; effect&nbsp; on the&nbsp; degree&nbsp; of&nbsp; adsorption&nbsp; of&nbsp; chlorinated phenols,&nbsp; benzene&nbsp; derivatives,&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; on microplastics.<br />The&nbsp; adsorption&nbsp; equilibrium&nbsp; between&nbsp; the&nbsp; concentration&nbsp; of&nbsp; chlorinated phenols,&nbsp; benzene derivatives and polycyclic aromatic hydrocarbons in water and selected types of microplastics (PEp, PE_PCPs_1, PE_PCPs_2, PEg, PET, PP, and&nbsp; PLA) was established after 24 and 48 h of contact time, depending on the selected&nbsp; group&nbsp; of&nbsp; organic&nbsp; pollutants.&nbsp; The&nbsp; adsorption&nbsp; affinity&nbsp; of&nbsp; chlorinated phenols,&nbsp; benzene&nbsp; derivatives,&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; towards microplastics&nbsp; was&nbsp; influenced&nbsp; by&nbsp; both&nbsp; the&nbsp; physicochemical&nbsp; properties&nbsp; of&nbsp; the compounds&nbsp; and&nbsp; the&nbsp; characteristics&nbsp; of&nbsp; the&nbsp; microplastics.&nbsp; Based&nbsp; on&nbsp; the&nbsp; kinetic experiments,&nbsp; the&nbsp; highest&nbsp; adsorption&nbsp; affinity&nbsp; for&nbsp; microplastics&nbsp; was&nbsp; shown&nbsp; by benzene derivatives (qt=103-350 &micro;g/g), while the lowest was&nbsp; observed during the adsorption of chlorinated phenols (qt=25-225 &micro;g/g). Benzene derivatives showed higher&nbsp; adsorption&nbsp; affinities&nbsp; for&nbsp; the&nbsp; selected&nbsp; microplastic&nbsp; particles&nbsp; than&nbsp; the polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; and&nbsp; &nbsp; chlorinated&nbsp; phenols&nbsp; which&nbsp; had&nbsp; similar logKow&nbsp; values. The influence of the water matrix on adsorption of chlorinated phenols,&nbsp; benzene&nbsp; derivatives,&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; on microplastics&nbsp; depended&nbsp; on&nbsp; the&nbsp; specific&nbsp; functional&nbsp; groups&nbsp; of&nbsp; the&nbsp; investigated compounds as well as on the type of microplastics. Water matrix had little impact on&nbsp; the&nbsp; adsorption&nbsp; of&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; on&nbsp; microplastics&nbsp; but greatly impacted the adsorption of chlorinated phenols. Fitting the pseudo-second order kinetic&nbsp; model to the&nbsp; adsorption data of chlorinated phenols, benzene derivatives, and polycyclic aromatic hydrocarbons on microplastic particles resulted in high correlation coefficients, indicating that chemisorption&nbsp; is&nbsp; the&nbsp; likely&nbsp; adsorption&nbsp; mechanism.&nbsp; In&nbsp; addition&nbsp; to&nbsp; the&nbsp; high correlation coefficients obtained for all the organic pollutants investigated, the pseudo-second order rate constants obtained were lower than the initiaadsorption rate, indicating significantly faster adsorption at shorter contact times (12-24 h), with adsorption slowing down as equilibrium was reached.The adsorption mechanism of chlorinated phenols, benzene derivatives,<br />and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons&nbsp; was&nbsp; investigated&nbsp; using Freundlich,Langmuir,&nbsp; Redlich-Peterson,&nbsp; Dubinine-Radusckevich,&nbsp; and&nbsp; Temkin&nbsp; adsorption models.&nbsp; The&nbsp; Freundlich&nbsp; exponent&nbsp; values&nbsp; for&nbsp; the&nbsp; adsorption&nbsp; of&nbsp; chlorinated phenols, benzene&nbsp; derivatives, and polycyclic&nbsp; aromatic&nbsp; hydrocarbons were&nbsp; less than 1 which indicates that the free energy of adsorption of these compounds on microplastics&nbsp; decreases&nbsp; as&nbsp; the&nbsp; initial&nbsp; concentration&nbsp; increases.&nbsp; The&nbsp; maximum adsorption capacities of PAHs on microplastic particles were in the range of 29.7-2596.5&nbsp; &micro;g/g.&nbsp; High&nbsp; maximum&nbsp; adsorption&nbsp; capacities&nbsp; were&nbsp; also obtained&nbsp; for the adsorption&nbsp; of&nbsp; benzene&nbsp; derivatives&nbsp; on&nbsp; the&nbsp; tested&nbsp; types&nbsp; of&nbsp; microplastics:&nbsp; 39.3-2010.1&nbsp; &micro;g/g.&nbsp; The&nbsp; chlorinated&nbsp; phenols&nbsp; behaved&nbsp; differently,&nbsp; and&nbsp; were&nbsp; more effected by the water matrix, with qmax values in&nbsp; the range 20.00-205.6 &micro;g/g. The pH of the water matrix was found to have a significant effect on the adsorption&nbsp; of&nbsp; chlorinated&nbsp; phenols&nbsp; on&nbsp; microplastics,&nbsp; whereas&nbsp; in&nbsp; the&nbsp; case&nbsp; of benzene&nbsp; derivatives&nbsp; and&nbsp; polycyclic&nbsp; aromatic&nbsp; hydrocarbons,&nbsp; the&nbsp; degree&nbsp; of<br />adsorption&nbsp; was&nbsp; largely&nbsp; independent&nbsp; of&nbsp; the&nbsp; water&nbsp; pH.&nbsp; For&nbsp; the&nbsp; adsorption&nbsp; of chlorinated&nbsp; phenols&nbsp; on&nbsp; microplastics,&nbsp; neutral&nbsp; pH&nbsp; conditions&nbsp; resulted&nbsp; in&nbsp; the greatest degrees of adsorption (55-65% at pH 7), while adsorption was inhibited under acidic (8-35% at pH 4) and basic (15-35% at pH 10) conditions. The microplastic type with the lowest observed adsorption affinities was PLA. It can be thus be assumed that in the event that this type of microplastic enters water systems, organic pollutants will only adsorb weakly to this material, such&nbsp; that&nbsp; it&nbsp; will&nbsp; have&nbsp; significantly&nbsp; less&nbsp; impact&nbsp; on&nbsp; the&nbsp; transport&nbsp; of&nbsp; the se compounds through the environment, than the other tested&nbsp; types of microplastics. The results obtained in this research demonstrate that the adsorption of the selected&nbsp; groups&nbsp; of&nbsp; organic&nbsp; pollutants&nbsp; on&nbsp; the&nbsp; microplastics&nbsp; investigated&nbsp; is significantly&nbsp; controlled&nbsp; by&nbsp; the&nbsp; physicochemical&nbsp; properties&nbsp; of&nbsp; the&nbsp; tested compounds, such as the dissociation constant, molecule&nbsp; size, hydrophobicity,<br />structural properties, etc. In addition, the characteristics of the water matrix play an important role in controlling adsorption of organic pollutants on microplastic, especially the water pH. In addition, the structure and aging of the polymers had a major influence&nbsp; on their interactions with the selected organic pollutants. The obtained&nbsp; results&nbsp; also&nbsp; demonstrate&nbsp; the&nbsp; difficulty&nbsp; in&nbsp; determining&nbsp; a&nbsp; uniform mechanism&nbsp; of&nbsp; adsorption&nbsp; between&nbsp; the&nbsp; various&nbsp; organic&nbsp; compounds&nbsp; and microplastic particles in water.</p>

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