Provider: - Institution: - Data provided by Europeana Collections- Environmental protection has been a topic of great attention in recent years. Discharging azo dyes in aquatic systems leads to contamination of water and exhibits serious ecological problems. Azo dyes are subject to bioaccumulation, and due to their allergenic, cancerogenic, mutagenic and teratogenic properties they are a grave threat to people and the environment. Adsorption process is becoming incerasingly popular as a way of treatment of various kinds of wastewaters, among them the azo-dyes containing ones, because it is economically feasible, processes are simple and there is a high level of efficiency present in such processes. The increasingly interesting adsorbents are those that stem from sustainable sources and are biodegradable – both from ecological and economical point of view. The aim of this study is preparation and characterization of polymer complexes based on naturally occuring polysaccharides – pectin and chitosan. This study presents the preparation and characterization of chitosan/poly(itaconic acid) and amidated pectin/poly(itaconic acid) complexes containing between 10 and 90% of poly(itaconic acid). The complexes chitosan/montmorillonite and amidated pectin/montmorillonite having between 10 and 50% of montmorillonite were prepared as well. The complexes were characterized by elemental analisys, Fourier Transformed Infrared spectroscopy, Scanning electron microscopy and thermogravimetry. FTIR analysis confirmed the composition of all complexes. SEM analysis confirmed the morphology of these complexes, and changes in morfology after dye adsorption. It was shown that after adsorption on the surface of complexes has changed, and a large number of agglomerate and roughness appeared. Thermogravimetry has shown that the amount of montmorilonite in chitosan/montmorillonite and amidated pectin/montmorillonite complexes had big influence on thermal stability. Montmorillonite increased thermal stability of complexes, but this effect was most pronounced at low amounts of MMT in the system, while at higher content of MMT the decomposition temperature decreased. Poly(itaconic acid) improved the thermal stability of complexes. This study investigated the adsorption kinetics of Reactive Orange 16 dye from aqueous solutions on chitosan/poly(itaconic acid) and chitosan/montmorillonite complexes using various component amounts. The adsorption kinetics of Basic Yellow 28 azo-dye from aqueous solutions on amidated pectin/poly(itaconic acid) and amidated 4 pectin/montmorillonite complexes in various component amounts have also been studied. The influence of initial dye concentration (30, 50 and 80 ppm), temperature (8, 25, 37 and 55˚C), pH value of the solution (2, 4, 5, 6 and 7,4) and the composition of complexes on the kinetics and adsorption mechanisms were the main focus of this work. The kinetics and adsorption mechanisms were investigated using four kinetic models: The Lagergren pseudofirst order model, the Ho pseudo-second order model, the Elovich model and the intraparticular diffusion model. Three adsorption isotherms models were applied – Langmuir, Freundlich and Temkin. Before the experimental part the theoretical introduction has been presented containing the relevant information needed to asses the width of the problem and understanding the prniciples on which this study was based. The results have shown that adsorption of Basic Yellow 28 didn’t occur onto amidated pectin/poly(itaconic acid) complexes. Investigation of adsorption of Basic Yellow 28 onto amidated pectin/montmorillonite complexes has shown that the amount of montmorillonite had a big influence on adsorption capacity. The adsorption capacity increased with increasing the concentration of dye, up to amount of montmorillonite of 30%. Further increase in amount of montmorillonite led to the decrease in adsorption capacity. Similar observation was found for adsorption of Reactive oragne 16 onto chitosan/montmorillonite complexes. The investigation of adsorption of Reactive Orange 16 dye onto chitosan/poly(itaconic acid) complexes showed that the adsorption at 20°C occurred only at lower amounts than 30 % of poly(itaconic acid) in complexes. At increased temperatures Reactive Orange 16 got adsorbed onto complexes containing up to 50 % of poly(itaconic acid). The comparison of absorption capacities of these complexes with the previously published ones, showed that the complexes presented in this investigation can efficiently replace the conventional adsorbents for removal of azo dyes from wastewaters.- Poslednjih godina se sve veća pažnja posvećuje očuvanju životne sredine. Ispuštanje azo boja u vodenu sredinu dovodi do kontaminacije vode i predstavlja ozbiljan ekološki problem. Azo boje podložne su bioakumulaciji, a zbog kancerogenih, mutagenih i teratogenih svojstava neretko su pretnja zdravlju ljudi i očuvanju okoline. Proces adsorpcije je sve zastupljeniji u obradi svih vrsta otpadnih voda, pa tako i onih koje sadrže azo boje, zbog ekonomičnosti, jednostavnosti procesa i stepena efikasnosti prečišćavanja otpadnih voda. S obzirom da se sve veća pažnja poklanja ispitivanju adsorbenata koji potiču iz obnovljivih izvora i koji su biodegradabilni, zbog ekoloških i ekonomskih uslova, predmet ovog rada je priprema i karakterizacija kompleksa koji se zasnivaju na prirodnim polisaharidima, pektinu i hitozanu. U ovom radu ispitivani su kompleksi hitozan/poli(itakonska kiselina) i amidovani pektin/poli(itakonska kiselina) pri udelima poli(itakonske kiseline) od 10-90% u kompleksu. Takodje, ispitivani su i kompleksi hitozan/montmorilonit i amidovani pektin/montmorilonit, pri udelu montmorilonita od 10-50%. Ovi kompleksi su karakterisani Elementarnom analizom, Fourier transformisanom infracrvenom spektroskopijom (FTIR), Skenirajućom elektronskom spektroskopijom (SEM) i Termogravimetrijom (TG). Analizom FTIR spektara je potvrđen sastav svih kompleksa. SEM analizom je utvrđena morfologija ovih kompleksa, kao i promene nastale na površini uzoraka nakon adsorpcije boje. Analizom termograma ustanovljeno je da montmorilonit ima veliki uticaj na termijsku stabilnost kompleksa hitozan/montmorilonit i amidovani pektin/montmorilonit. Montmorilonit pri malom udelu u kompleksu, dovodi do povećane termijske stabilnosti, naspram čistog hitozana, odnosno amidovanog pektina, dok sa porastom montmorilonita do 50% u kompleksu, dolazi do opadanja termijske stabilnosti. Poli(itakonska kiselina) takodje pospešuje termijsku stabilnost kompleksa naspram čistih komponenti. U ovom radu je ispitana kinetika adsorpcije anjonske Reactive Orange 16 boje iz vodenih rastvora na komplekse hitozan/poli(itakonska kiselina) i hitozan/montmorilonit, pri različitim odnosima komponenti u kompleksu. Takodje, ispitivana je i kinetika adsorpcije katjonske Basic Yellow 28 boje iz vodenih rastvora na komplekse amidovani pektin/poli(itakonska kiselina) i amidovani pektin/montmorilonit pri različitim odnosima komponenti. Ispitivan je uticaj početne koncentracije boje (30, 50 i 80 ppm), zatim uticaj temperature (8, 25, 37 i 55°C), uticaj pH vrednosti rastvora (2, 4, 5, 6 i 7,4) , kao i uticaj različitog odnosa komponenti u kompleksu na kinetiku adsorpcije i adsorpcioni kapacitet. Radi utvrdjivanja kinetike i 2 mehanizma adsorpcije, ispitivana su četiri različita kinetiča modela: Lagergren-ov model pseudo-prvog reda, Ho-ov model pseudo-drugog reda, Jelovičev model i model unutarčestične difuzije. Ispitivana su tri modela adsorpcionih izotermi: Langmuir-ova, Freundlich-ova i Temkin-ova adsorpciona izoterma. Rezultati su pokazali da ne dolazi do adsorpcije boje Basic Yellow 28 na komplekse amidovani pektin/poli(itakonska kiselina). Pri ispitivanju adsorpcije boje Basic Yellow 28 na komplekse amidovani pektin/montmorilonit, ustanovljeno je da udeo montmorilonita ima veliki uticaj na kapacitet adsorpcije. Kapacitet adsorpcije raste sa porastom koncentracije rastvora boje, sa porastom pH, i sa porastom udela montmorilonita do 30%. Daljim povećanjem udela montmorilonita u kompleksu dolazi do opadanja kapaciteta adsorpcije. Slična zavisnost udela montmorilonita i kapaciteta adsorpcije je uočena i kod adsorpcije boje Reactive Orange 16 na komplekse hitozan/montmorilonit. Ispitivanjem adsorpcije boje Reactive Orange 16 na komplekse hitozan/poli(itakonska kiselina) uočeno je da do adsorpcije na sobnoj temperaturi dolazi samo pri udelu poli(itakonske kiseline) u kompleksu manjem od 30%. Na povišenoj temperaturi dolazi do adsorpcije Reactive Orange 16 boje na kompleksima sa udelom poli(itakonske kiseline) i do 50%. Poredjenjem kapaciteta adsorpcije boje na pomenutim sistemima u ovom istraživanju sa podacima iz literature, utvrdjeno je da adsorbenti ispitani u ovom radu mogu efikasno zameniti konvencionalne adsorbente za uklanjanje azo boja iz otpadnih voda.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana