Amino-functionalization of methacrylate based polymers and their interaction with cr(vi), tc(vii), re(vii) and mo(vi) oxyanions in aqueous systems

Cilj ove doktorske disertacije je bio ispitivanje uticaja stepena umreženja i makroporoznosti na strukturne karakteristike i termička svojstva neporoznih i makroporoznih metakrilatnih homopolimera i kopolimera sintetizovanih suspenzionom (ko)polimerizacijom. Pored toga u disertaciji je ispitivana mogućnost primene kopolimera glicidilmetakrilata (GMA) i etilenglikoldimetakrilata (EGDMA) sa različitim udelom umreživača funkcionalizovanih dietilentriaminom (skraćeno PGME-deta) za uklanjanje oksianjona teških metala i radionuklida Cr(VI), 99Tc(VII), Re(VII) i Mo(VI) iz vodenih sistema. Šaržnom metodom pri nekompetitivnim uslovima je ispitan uticaj nekoliko ključnih faktora na kapacitet i kinetiku sorpcije u ovim sistemima: vremena kontakta, početne koncentracije metala u rastvoru, pH rastvora, temperature i parametara porozne strukture kopolimera. Polimeri su okarakterisani fizičkohemijskim metodama: mikroanalizom, skenirajućom elektronskom mikroskopijom sa energetski disperzivnom spektroskopijom x-zraka (SEM/EDS) i transmisionom elektronskom mikroskopijom (TEM), infracrvenom spektroskopijom (FTIR-ATR), živinom porozimetrijom, adsorpciono–desorpcionim izotermama N2 na 77 K i termijskom analizom (TG/DSC) sa masenom spektrometrijom (MS). Rezultati dobijeni ispitivanjem sorpcije Cr(VI), 99Tc(VII), Re(VII) i Mo(VI) iz vodenih rastvora na amino-funkcionalizovanim kopolimerima u laboratorijskim uslovima bili su osnova za proučavanje kinetičkih reakcionih i difuzionih modela, adsorpcionih izotermi i termodinamike sorpcije, da bi se dobio uvid u mehanizam procesa i ocenila efikasnost ovih sorbenasa.The goal of this doctoral dissertation was to investigate the influence of crosslinking extent and macroporosity on structural characteristics and thermal properties of nonporous and macroporous methacrylate-based homopolymers and copolymers synthesized by suspension (co)polymerization. Also, the possible application of the copolymers of glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EGDMA) with different crosslinker content functionalized with diethylene triamine (abbreviated PGME-deta) was investigated for the removal of heavy metal and radionuclide oxyanions Cr(VI), 99Tc(VII), Re(VII) and Mo(VI) from aqueous systems. The influence of several key characteristics on sorption capacity and kinetics: contact time, initial metal concentration in the solution, solution pH, temperature and parameters of porous structure, was investigated using batch method under noncompetitive conditions. Polymers were characterized using physicochemical methods: microanalysis, scanning electron microscopy with energy-dispersive x-ray spectroscopy (SEM/EDS) and transmission electron microscopy (TEM), infrared spectroscopy (FTIR-ATR), mercury porosimetry, N2 adsorption‒desorption isotherms at 77 K and thermal analysis (TG/DSC) with mass spectrometry (MS). The obtained results of Cr(VI), 99Tc(VII), Re(VII) and Mo(VI) sorption from aqueous solutions on the amino-functionalized copolymers in laboratory conditions were the base of the analysis of the surface reaction-based and pore diffusion-based kinetic models, adsorption isotherms and thermodynamics of sorption, in order to gain insight into the mechanism of the process and evaluate the efficiency of these sorbents

Amino-functionalization of methacrylate based polymers and their interaction with cr(vi), tc(vii), re(vii) and mo(vi) oxyanions in aqueous systems

Cilj ove doktorske disertacije je bio ispitivanje uticaja stepena umreženja imakroporoznosti na strukturne karakteristike i termička svojstva neporoznih imakroporoznih metakrilatnih homopolimera i kopolimera sintetizovanih suspenzionom(ko)polimerizacijom. Pored toga u disertaciji je ispitivana mogućnost primenekopolimera glicidilmetakrilata (GMA) i etilenglikoldimetakrilata (EGDMA) sarazličitim udelom umreživača funkcionalizovanih dietilentriaminom (skraćenoPGME-deta) za uklanjanje oksianjona teških metala i radionuklida Cr(VI), 99Tc(VII),Re(VII) i Mo(VI) iz vodenih sistema. Šaržnom metodom pri nekompetitivnim uslovimaje ispitan uticaj nekoliko ključnih faktora na kapacitet i kinetiku sorpcije u ovimsistemima: vremena kontakta, početne koncentracije metala u rastvoru, pH rastvora,temperature i parametara porozne strukture kopolimera.Polimeri su okarakterisani fizičkohemijskim metodama: mikroanalizom,skenirajućom elektronskom mikroskopijom sa energetski disperzivnomspektroskopijom x-zraka (SEM/EDS) i transmisionom elektronskom mikroskopijom(TEM), infracrvenom spektroskopijom (FTIR-ATR), živinom porozimetrijom,adsorpciono–desorpcionim izotermama N2 na 77 K i termijskom analizom (TG/DSC) samasenom spektrometrijom (MS).Rezultati dobijeni ispitivanjem sorpcije Cr(VI), 99Tc(VII), Re(VII) i Mo(VI) izvodenih rastvora na amino-funkcionalizovanim kopolimerima u laboratorijskimuslovima bili su osnova za proučavanje kinetičkih reakcionih i difuzionih modela,adsorpcionih izotermi i termodinamike sorpcije, da bi se dobio uvid u mehanizamprocesa i ocenila efikasnost ovih sorbenasa.The goal of this doctoral dissertation was to investigate the influence ofcrosslinking extent and macroporosity on structural characteristics and thermalproperties of nonporous and macroporous methacrylate-based homopolymers andcopolymers synthesized by suspension (co)polymerization. Also, the possibleapplication of the copolymers of glycidyl methacrylate (GMA) and ethylene glycoldimethacrylate (EGDMA) with different crosslinker content functionalized withdiethylene triamine (abbreviated PGME-deta) was investigated for the removal of heavymetal and radionuclide oxyanions Cr(VI), 99Tc(VII), Re(VII) and Mo(VI) from aqueoussystems. The influence of several key characteristics on sorption capacity and kinetics:contact time, initial metal concentration in the solution, solution pH, temperature andparameters of porous structure, was investigated using batch method undernoncompetitive conditions.Polymers were characterized using physicochemical methods: microanalysis,scanning electron microscopy with energy-dispersive x-ray spectroscopy (SEM/EDS)and transmission electron microscopy (TEM), infrared spectroscopy (FTIR-ATR),mercury porosimetry, N2 adsorption‒desorption isotherms at 77 K and thermal analysis(TG/DSC) with mass spectrometry (MS).The obtained results of Cr(VI), 99Tc(VII), Re(VII) and Mo(VI) sorption fromaqueous solutions on the amino-functionalized copolymers in laboratory conditionswere the base of the analysis of the surface reaction-based and pore diffusion-basedkinetic models, adsorption isotherms and thermodynamics of sorption, in order to gaininsight into the mechanism of the process and evaluate the efficiency of these sorbents

Amino-functionalization of methacrylate based polymers and their interaction with cr(vi), tc(vii), re(vii) and mo(vi) oxyanions in aqueous systems

Cilj ove doktorske disertacije je bio ispitivanje uticaja stepena umreženja imakroporoznosti na strukturne karakteristike i termička svojstva neporoznih imakroporoznih metakrilatnih homopolimera i kopolimera sintetizovanih suspenzionom(ko)polimerizacijom. Pored toga u disertaciji je ispitivana mogućnost primenekopolimera glicidilmetakrilata (GMA) i etilenglikoldimetakrilata (EGDMA) sarazličitim udelom umreživača funkcionalizovanih dietilentriaminom (skraćenoPGME-deta) za uklanjanje oksianjona teških metala i radionuklida Cr(VI), 99Tc(VII),Re(VII) i Mo(VI) iz vodenih sistema. Šaržnom metodom pri nekompetitivnim uslovimaje ispitan uticaj nekoliko ključnih faktora na kapacitet i kinetiku sorpcije u ovimsistemima: vremena kontakta, početne koncentracije metala u rastvoru, pH rastvora,temperature i parametara porozne strukture kopolimera.Polimeri su okarakterisani fizičkohemijskim metodama: mikroanalizom,skenirajućom elektronskom mikroskopijom sa energetski disperzivnomspektroskopijom x-zraka (SEM/EDS) i transmisionom elektronskom mikroskopijom(TEM), infracrvenom spektroskopijom (FTIR-ATR), živinom porozimetrijom,adsorpciono–desorpcionim izotermama N2 na 77 K i termijskom analizom (TG/DSC) samasenom spektrometrijom (MS).Rezultati dobijeni ispitivanjem sorpcije Cr(VI), 99Tc(VII), Re(VII) i Mo(VI) izvodenih rastvora na amino-funkcionalizovanim kopolimerima u laboratorijskimuslovima bili su osnova za proučavanje kinetičkih reakcionih i difuzionih modela,adsorpcionih izotermi i termodinamike sorpcije, da bi se dobio uvid u mehanizamprocesa i ocenila efikasnost ovih sorbenasa.The goal of this doctoral dissertation was to investigate the influence ofcrosslinking extent and macroporosity on structural characteristics and thermalproperties of nonporous and macroporous methacrylate-based homopolymers andcopolymers synthesized by suspension (co)polymerization. Also, the possibleapplication of the copolymers of glycidyl methacrylate (GMA) and ethylene glycoldimethacrylate (EGDMA) with different crosslinker content functionalized withdiethylene triamine (abbreviated PGME-deta) was investigated for the removal of heavymetal and radionuclide oxyanions Cr(VI), 99Tc(VII), Re(VII) and Mo(VI) from aqueoussystems. The influence of several key characteristics on sorption capacity and kinetics:contact time, initial metal concentration in the solution, solution pH, temperature andparameters of porous structure, was investigated using batch method undernoncompetitive conditions.Polymers were characterized using physicochemical methods: microanalysis,scanning electron microscopy with energy-dispersive x-ray spectroscopy (SEM/EDS)and transmission electron microscopy (TEM), infrared spectroscopy (FTIR-ATR),mercury porosimetry, N2 adsorption‒desorption isotherms at 77 K and thermal analysis(TG/DSC) with mass spectrometry (MS).The obtained results of Cr(VI), 99Tc(VII), Re(VII) and Mo(VI) sorption fromaqueous solutions on the amino-functionalized copolymers in laboratory conditionswere the base of the analysis of the surface reaction-based and pore diffusion-basedkinetic models, adsorption isotherms and thermodynamics of sorption, in order to gaininsight into the mechanism of the process and evaluate the efficiency of these sorbents

Introduction of transition metal cations (Co2+ and Zn2+) into dealuminated NaY zeolite obtained by citric acid treatment

Aluminum ions were extracted from the framework of the faujasite type zeolite NaY (Si/Al=2.4) by citric acid treatment. Dealuminated CoY and ZnY zeolites of high cobalt and zinc content were prepared by replacing sodium ions with Co2+ and Zn2+ in dealuminated Y zeolites, with increased framework Si/Al ratio. Chemical and XRD analyses of zeolites were performed and the FTIR-ATR spectra were recorded. The results of physicochemical analyses are discussed in terms of unit cell (u.c.) composition

Makroporozni kopolimer na bazi glicidilmetakrilata funkcionalizovan sa dietilentriaminom kao sorbent tekstilne boje Reactive Black 5

In this paper, macroporous glycidyl methacrylate and ethylene glycol dimethacrylate copolymer functionalized with diethylene triamine (PGME-deta), was evaluated as Reactive Black 5 (RB5) sorbent. Batch RB5 removal from aqueous solution by PGME-deta was investigated by varying pH, contact time, sorbent dosage, initial dye concentration and temperature. The sorption is pH sensitive having maximum at pH 2 (dye removal of 85%), decreasing with the increase of pH (dye removal of 24% at pH 11) after 60 min. Sorption kinetics was fitted to chemical-reaction and particle-diffusion models (pseudo-first-, pseudo-second-order, intraparticle diffusion and Mckay models). The pseudo-second-order kinetic model accurately predicted the RB5 amount sorbed under all investigated operating conditions, while the intraparticle diffusion was the dominant rate-limiting mechanism. The diffusion mechanism was more prevalent with the decrease in temperature and the increase in concentration. The isotherm data was best fitted with the Langmuir model, indicating homogeneous distribution of active sites on PGME-deta and monolayer sorption, with the maximum sorption capacity of 353 mg g(-1). The calculated sorption rates improved with increasing temperature and an activation energy close to 40 kj mol(-1) was determined, suggesting that chemisorption was also rate-controlling.U okviru ovog rada ispitana je mogućnost korišćenja makroporoznog kopolimera glicidilmetakrilata i etilenglikoldimetakrilata funkcionalizovanog reakcijom otvaranja epoksidnih grupa sa dietilentriaminom (PGME-deta) kao sorbenta reaktivne tekstilne boje Reactive Black 5 (RB5). U šaržnim uslovima je ispitano uklanjanje RB5 iz vodenog rastvora pomoću PGME-deta, variranjem pH, vremena kontakta, mase sorbenta, početne koncentracije boje i temperature. PGME-deta je pokazao afinitet za sorpciju RB5 zbog prisustva protonovanih amino grupa koje privlače anjonske sulfonatne grupe u molekulu boje i mogućnosti stvaranja vodoničnih veza između sorbenta i sorbata. Kinetika sorpcije je analizirana pomoću četiri kinetička modela (pseudo-prvog, pseudo-drugog reda, unutarčestične difuzije i Mekej) da bi se odredilo koji model najbolje opisuje sorpciju RB5. Zapažen je izrazit uticaj pH vrednosti na sorpciju RB5, sa maksimumom na pH 2 (pri čemu je efikasnost uklanjanja boje 85%), i smanjenjem količine sorbovane boje sa povećanjem pH (količina uklonjene boje na pH 11 posle 60 min iznosi samo 24%). Izučavanjem kinetike sorpcije pokazalo se da sorpcija RB5 pomoću PGME-deta sledi kinetički model pseudo-drugog reda (PSO), sugerišući da je brzina sorpcije kontrolisana kapacitetom sorbenta i koncentracijom sorbata. Mehanizam procesa dominantno čini unutarčestična difuzija, uz manji uticaj difuzije kroz film. Ovi mehanizmi difuzije su izraženiji pri nižim temperaturama i većim koncentracijama. Langmirov model najbolje opisuje ravnotežnu izotermu, ukazujući na homogenu raspodelu aktivnih mesta na površini PGME-deta i monoslojnu sorpciju. Maksimalni sorpcioni kapacitet izračunat iz Langmirove izoterme iznosi 353 mg g-1. Zapaženo je da se brzina sorpcije povećava sa povećanjem temperature. Izračunata vrednost aktivacione energije od oko 40 kJ mol-1 potvrđuje da se radi o procesu koji dominantno kontroliše hemisorpcija

Hexavalent chromium sorption by glycidyl methacrylate based copolymer

Macroporous crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate), PGME, was synthesized by suspension copolymerization and functionalized with diethylene triamine [PGME-deta]. Competitive sorption kinetics was studied from multicomponent Cr(VI), Cu(II), Co(II) and Cd(II) solution. Two kinetic models (the pseudo-first and the pseudo-second order) were used to determine the best-fit equation for the metals sorption by PGME-deta

Kinetics study of molybdenum sorption on amino-functionalized copolymer

Macroporous crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) [PGME-deta] functionalized with diethylene triamine was used for removal of Mo(VI) oxyanions from aqueous solutions. Kinetics of Mo(VI) sorption was investigated in batch experiments by varying initial Mo(VI) concentration. Sorption kinetics data was fitted to chemical-reaction and particle-diffusion models. It was shown that Mo(VI) sorption adhered to the pseudo-second-order kinetic model, with a definite influence of pore diffusion. The maximum Mo(VI) sorption capacity at pH 2.0 and 298K was 391 mg g-1

Efficient separation of Tc-99 from aqueous solution using pinecone activated carbon

Sorption of radioactive 99Tc-pertechnetate onto activated carbon prepared from pinecones was investigated. The parameters of contact time and Tc-99 concentration were varied. It was established that the sorption half-life, t1/2, was very short ~ 2.2 min, thus making this sorbent an excellent candidate for immediate pollution remediation, which is very important in the case of nuclear accidents. The kinetic data were found to follow closely the pseudosecond- order (PSO) kinetic model. Boyd model established the sorption dependence only on film diffusion. The partitioning/distribution coefficient, Kd, attained was 2729 cm3 g-1. The equilibration time was 3 h at room temperature (T=298 K)

Textural properties of macroporous acid modified montmorillonite nanocomposites

Macroporous crosslinked copolymer, poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) and its nanocomposites with acid modified montmorillonite (WA) were synthesized by radical suspension copolymerization. Nanocomposites were obtained by introducing various amounts of WA into the reaction system. Textural properties of synthesized samples were analyzed by mercury intrusion porosimetry. The synthesized nanocomposites have significantly higher specific surface area in comparison to the copolymer. Total pore volume and the most dominant pore diameter decrease with incorporation of acid modified montmorillonite in copolymer matrix.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 201

Thermal behaviour of some nonporous methacrylate polymers

Three nonporous methacrylate polymer samples were synthesized by suspension polymerization, and subsequently investigated. The surface area and the surface morphology of the spherical beads were examined by the BET method from the low-temperature adsorption isotherms and by scanning electron microscopy (SEM), respectively. Thermal behaviour of the two homopolymer samples, poly(glycidyl methacrylate) (PGMA) and poly(ethylene glycol dimethacrylate) (PEGDMA), and the copolymer sample poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) (PGME) was investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). All samples exhibit complex thermal degradation behavior. The copolymer is intermediate in stability between PGMA and PEGDMA