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Adsorption of heavy metal ions from aqueousb solution using wheat straw as an adsorbent.

dc.contributor.advisorŠtrbac, Nada
dc.contributor.otherRajčić-Vujasinović, Mirjana
dc.contributor.otherŽivković, Dragana
dc.contributor.otherCakić, Milorad
dc.creatorGorgievski, Milan D.
dc.date.accessioned2020-07-03T09:17:06Z
dc.date.available2020-07-03T09:17:06Z
dc.date.issued2015-04-27
dc.identifier.urihttp://nardus.mpn.gov.rs/handle/123456789/5739
dc.identifier.urihttp://eteze.bg.ac.rs/application/showtheses?thesesId=3144
dc.identifier.urihttps://fedorabg.bg.ac.rs/fedora/get/o:11462/bdef:Content/download
dc.identifier.urihttp://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=47594255
dc.description.abstractU disertaciji su prikazani rezultati adsorpcije Cu2+, Ni2+, Zn2+ i Pb2+ jona iz sintetičkih rastvora korišćenjem pšenične slame kao adsorbensa. Eksperimenti adsorpcije su izvođeni u reaktoru sa mešanjem i u adsorpcionoj koloni. Izvršena je karakterizacija pšenične slame; određene su fizičke, hemijske i fizičko-hemijske osobine. Određen je sadržaj organskih materija u vodi od ispiranja slame destilisanom vodom na osnovu hemijske potrošnje kiseonika (HPK). Dobijena vrednost za HPK je iznosila 18 mgO2/dm3. Određen je sadržaj alkalnih i zemnoalkalnih metala, pre i nakon ispiranja slame destilisanom vodom, kao i nakon zasićenja datim jonima metala. Određen je i kapacitet izmene katjona (KIK) između slame i vodene faze, standardnom metodom jonske izmene sa NH4Cl. Ukupni KIK iznosio je 1,86 mmol Mez+/g slame (Mez+ ovde predstavlja jone alkalnih i zemnoalkalnih metala). Na osnovu dobijenih rezultata za KIK dominantan jon u izmenjivom položaju je Ca2+ jon. Određena je tačka nultog naelektrisanja (pHzpc) pšenične slame, pri čemu je dobijena vrednost od 6,5 za koncentraciju 0,1 M KNO3, odnosno 6,7 za koncentraciju 0,01 M KNO3. SEM analiza pšenične slame, pre i posle adsorpcije datih jona metala, ukazuje na jasne morfološke promene površine pšenične slame nakon adsorpcije. FTIR analiza pšenične slame pre i posle adsorpcije jona bakra, pokazala je da su O-H i C-O funkcionalne grupe u strukturi pšenične slame moguća mesta vezivanja Cu2+ jona. Do porasta pH vrednosti rastvora, tokom ispiranja slame destilisanom vodom, dolazi usled prelaska H+ jona iz vodene faze u strukturu slame, gde bivaju izmenjeni sa Ca2+ jonima. Porast provodljivosti rastvora, tokom ispiranja slame destilisanom vodom posledica je porasta koncentracije Na+, K+, Ca2+ i Mg2+ jona u rastvoru koji se ispiranjem samoizlužuju i prelaze iz strukture slame u vodenu fazu. Maksimalni kapacitet adsorpcije (9,3 mg g-1 slame) dobijen je za adsorpciju Pb2+ jona, dok je kapacitet adsorpcije Cu2+, Ni2+ i Zn2+ jona iznosio 5 mg g-1, 2,5 mg g−1 i 3,25 mg g−1 slame, redom. Do smanjenja pH vrednosti tokom adsorpcije Cu2+, Zn2+ i Pb2+ jona dolazi usled deprotonizacije funkcionalnih grupa u slami i prelaska H+ jona u rastvor. Porast pH vrednosti rastvora tokom adsorpcije Ni2+ jona govori o tome da se paralelno sa adsorpcijom Ni2+ jona na slami odvija i adsorpcija H+ jona. Za opisivanje kinetike adsorpcije datih jona na slami, najbolje slaganje sa eksperimentalnim podacima dao je kinetički model pseudo-drugog reda. Za opisivanje ravnoteže adsorpcije Cu2+, Ni2+ i Zn2+ jona na pšeničnoj slami najbolje slaganje sa eksperimentalnim podacima dali su Langmuir-ov i Temkin-ov model adsorpcione izoterme. Za opisivanje ravnoteže adsorpcije Pb2+ jona na slami, najbolje slaganje sa eksperimentalnim podacima dao je Temkin-ov model adsorpcione izoterme. Za eksperimente adsorpcije u koloni, stepen adsorpcije Cu2+, Ni2+ i Zn2+ jona, pre dostizanja probojne tačke, je iznosio 99,4 %, 99,1 % i 99,65 %, redom. Stepen adsorpcije Cu2+, Ni2+ i Zn2+ jona iz ternarnog rastvora datih jona metala, pre dostizanja probojne tačke, je iznosio 99,2 %, 95 % i 90 %, redom. Pretpostavka je da se zemnoalkalni metali (pre svega kalcijum), prisutni u molekulskoj strukturi pšenične slame, mehanizmom jonske izmene izmenjuju sa datim jonima teških metala i protonima iz rastvora tokom procesa adsorpcije. Afinitet adsorbensa prema datom jonu metala je u korelaciji sa fizičko-hemijskim osobinama (jonski radijus, elektronegativnost, elektronska konfiguracija) datog jona metala. Dobijeni rezultati ukazuju da se pšenična slama može uspešno koristiti kao jeftin, prirodni adsorbens za adsorpciju Cu2+, Ni2+, Zn2+ i Pb2+ jona iz vodenih rastvora.sr
dc.description.abstractThe results of adsorption of Cu2+, Ni2+, Zn2+ and Pb2+ ions from synthetic solutions by using wheat straw are presented in this disertation. Physical, chemical and physico-chemical characterization of wheat straw was carried out. Chemical oxygen demand (COD) of rinsed water was determined prior to the adsorption experiments. The consumption of oxygen was 18 mg O2/dm3. The content of alkali and alkaline-earth metals, before and after rinsing of wheat straw with water, and after loading the adsorbent with Cu2+, Zn2+, Ni2+ and Pb2+ ions, was given. The cation exchange capacity (CEC) of alkali and alkaline-earth metals, exchanged in the reaction with NH4Cl, was also determined. The determined total CEC of the wheat straw was 1.86 mmol Mez+ g-1 (Mez+ denotes exchanged alkali and alkaline earth metal ions). Based on the CEC results, the dominant ion in the exchangeable position is Ca2+ ion. The point of zero charge (pHzpc) was determined. The obtained value was 6.5 for . 0.1 M KNO3, i.e., 6.7 for 0.01 M KNO3. SEM analysis of wheat straw before and after adsorption of considered metal ions indicates, the obvious morphological changes of the wheat straw surface after adsorption of the metal ions. The FTIR spectra analysis of wheat straw before and after adsorption of Cu2+ ions revealed that O-H and C-O functional groups are possible sites for Cu2+ ions bonding. The increase in the initial pH value of the solution, during rinsing wheat straw with distilled water, occurs due to a transfer of H+ ions from the aqueous phase to the molecular structure of straw, to be exchanged there with Ca2+ ions. The increase in the conductivity of the solution, during rinsing wheat straw with distilled water, was due to the increase in the concentration of Na+, K+, Ca2+ i Mg2+ ions in the solution, which were leached from the straw via a leaching mechanism. The maximum adsorption capacity of 9.3 mg g-1 was achieved for Pb2+ ions, while the adsorption capacity for Cu2+, Ni2+ and Zn2+ ions was 5 mg g-1, 2.5 mg g-1 and 3.25 mg g-1, respectively. Kinetics of adsorption was modelled by a pseudo-second order kinetic model showing a very good fitting with experimental data for all the considered metal ions. The adsorption equilibrium data for Cu2+, Ni2+ and Zn2+ ions can be well modelled by the Langmuir and Temkin adsorption isotherm model. The adsorption equilibrium data for Pb2+ ions can be well modelled by the Temkin adsorption isotherm model. In the column experiments, the adsorption degree of Cu2+, Ni2+ and Zn2+ ions, before reaching the breakthrough point, was 99.4 %, 99.1 % and 99.65 %, respectively. The adsorption degree of Cu2+, Ni2+ and Zn2+ ions from ternary solution, before reaching the breakthrough point, was 99.2 %, 95 % and 90 %, respectively. It is assumed that the alkaline-earth metals (mostly calcium), from wheat straw, are substituted by the considered heavy metal ions and protons during the adsorption process. The affinity of the adsorbent to a considered metal ion is correlated with the physico-chemical properties (ionic radius, electronegativity, electronic configuration) of a given metal ion. The obtained results show that wheat straw can be successfully used as cheap, natural adsorbent for the adsorption of Cu2+, Zn2+, Ni2+ and Pb2+ ions from aqueous solutions, contaning few ppm of heavy metal ions.en
dc.formatapplication/pdf
dc.languagesr
dc.publisherУниверзитет у Београду, Технички факултет, Борsr
dc.relationinfo:eu-repo/grantAgreement/MESTD/Technological Development (TD or TR)/34024/RS//
dc.relationinfo:eu-repo/grantAgreement/MESTD/Integrated and Interdisciplinary Research (IIR or III)/46010/RS//
dc.rightsopenAccessen
dc.sourceУниверзитет у Београдуsr
dc.subjectteški metalisr
dc.subjectheavy metalsen
dc.subjectpšenična slamasr
dc.subjectadsorpcijasr
dc.subjectmehanizam adsorpcijesr
dc.subjectkinetika adsorpcijesr
dc.subjectizoterme adsorpcijesr
dc.subjectwheat strawen
dc.subjectadsorptionen
dc.subjectadsorption mechanismen
dc.subjectadsorption kineticsen
dc.subjectadsorption isothermsen
dc.titleAdsorpcija jona teških metala iz vodenih rastvora korišćenjem pšenične slame kao adsorbensasr
dc.titleAdsorption of heavy metal ions from aqueousb solution using wheat straw as an adsorbent.en
dc.typedoctoralThesis
dc.rights.licenseBY-NC-ND
dcterms.abstractШтрбац, Нада; Рајчић-Вујасиновић, Мирјана; Живковић, Драгана; Цакић, Милорад; Горгиевски, Милан Д.; Aдсорпција јона тешких метала из водених раствора коришћењем пшеничне сламе као адсорбенса; Aдсорпција јона тешких метала из водених раствора коришћењем пшеничне сламе као адсорбенса;
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/16773/Gorgievski_Milan_D.pdf
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/16772/d_Gorgievski_disertacija.pdf


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