Information Resources on Chemistryhttp://dr.lib.sjp.ac.lk/handle/123456789/13572024-03-29T08:29:43Z2024-03-29T08:29:43ZClay-biochar composites for sorptive removal of tetracycline antibiotic in aqueous mediaPremarathna, K.S.D.Rajapaksha, Anushka UpamaliAdassoriya, NadeeshBinoy Sarkar, BinoySirimuthu, Narayana M.S.Cooray, AsithaOk, Yong SikVithanage, Meththikahttp://dr.lib.sjp.ac.lk/handle/123456789/84032019-07-03T03:47:38Z2019-01-01T00:00:00ZClay-biochar composites for sorptive removal of tetracycline antibiotic in aqueous media
Premarathna, K.S.D.; Rajapaksha, Anushka Upamali; Adassoriya, Nadeesh; Binoy Sarkar, Binoy; Sirimuthu, Narayana M.S.; Cooray, Asitha; Ok, Yong Sik; Vithanage, Meththika
The focus of this research was to synthesize novel clay-biochar composites by incorporating montmorillonite
(MMT) and red earth (RE) clay materials in a municipal solid waste (MSW) biochar for the adsorptive removal of
tetracycline (TC) from aqueous media. X-ray Fluorescence Analysis (XRF), Fourier Transform Infrared
Spectroscopy (FTIR), Powder X-ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM) were used for
the characterization of the synthesized raw biochar (MSW-BC) and clay-biochar composites (MSW-MMT and
MSW-RE). Results showed that minute clay particles were dispersed on biochar surfaces. The FTIR bands due to
Si-O functional group vibrations in the spectra of the clay-biochar composites provided further evidence for
successful composite formation. The kinetic TC adsorption data of MSW-MMT were well fitted to the Elovich
model expressing high surface activity of biochar and involvement of multiple mechanisms in the adsorption.
The kinetic TC adsorption data of MSW-BC and MSW-RE were fitted to the pseudo second order model indicating
dominant contribution of chemisorption mechanism during the adsorption. The adsorption differentiation obtained
in the kinetic studies was mainly due to the structure of the combined clay material. The adsorption
isotherm data of all the adsorbents were well fitted to the Freundlich model suggesting that the adsorption of TC
onto the materials occurred via both physisorption and chemisorption mechanisms. In comparison to the raw
biochar and MSW-RE, MSW-MMT exhibited higher TC adsorption capacity. Therefore, MSW-MMT clay-biochar
composite could be applied in the remediation of TC antibiotic residues in contaminated aqueous media.
2019-01-01T00:00:00ZFluorocarbon Separation in a Thermally Robust Zirconium Carboxylate Metal–Organic FrameworkDarshika K. J. A. WanigarathnaJiajian GaoBin Liuhttp://dr.lib.sjp.ac.lk/handle/123456789/83892019-06-11T08:52:15Z2018-01-01T00:00:00ZFluorocarbon Separation in a Thermally Robust Zirconium Carboxylate Metal–Organic Framework
Darshika K. J. A. Wanigarathna; Jiajian Gao; Bin Liu
2018-01-01T00:00:00ZBiofilm mediated synergistic degradation of hexadecane by a naturally formed community comprising Aspergillus flavus complex and Bacillus cereus groupMadushika PereraDilrukshi WijayarathnaSulochana WijesunderaManoj ChinthakaGamini Seneviratne'http://dr.lib.sjp.ac.lk/handle/123456789/83712019-05-31T04:35:16Z2019-01-01T00:00:00ZBiofilm mediated synergistic degradation of hexadecane by a naturally formed community comprising Aspergillus flavus complex and Bacillus cereus group
Madushika Perera; Dilrukshi Wijayarathna; Sulochana Wijesundera; Manoj Chinthaka; Gamini Seneviratne'
Attached
2019-01-01T00:00:00ZSynthesis, Structural Characterization, and Volatility Evaluation of Zirconium and Hafnium Arnidate ComplexesKarunarathne, M.C.Baumann, J.W.Heeg, M.J.Martin, P.D.http://dr.lib.sjp.ac.lk/handle/123456789/70062023-03-22T07:51:11Z2017-01-01T00:00:00ZSynthesis, Structural Characterization, and Volatility Evaluation of Zirconium and Hafnium Arnidate Complexes
Karunarathne, M.C.; Baumann, J.W.; Heeg, M.J.; Martin, P.D.
Attached; Treatment of tetrakis(dimethylamido)zirconium or tetrakis(dimethylamido)hafnium with four equivalents of N-rerr-butylacetamide. N-isopropylisobutyramide. N-isopropylacetamide. N-methylacetamide.
or N-terr-butylformamide in refluxing toluene. followed by sublimation of the crude products at 105
-125 °CI0.05 Torr. afforded tetrakis(N-rerr-butylacetamido )zirconium (81 %). tetrakis(Nisopropylisobutyramido )zirconium (87%). tetrakis(N-isopropylacetamido )zirconium (51 %), tetrakis(Nterr-butylacetamido )hafnium (83%), tetrakis( N-isopropyliso-butyramido )hafnium (79%), tetralds(Nisopropylacetamido)hafnium (67%), tetrakis(N-methylacetamido)zirconium (5%), and tetrakis(N-rertbutylformamido)zirconium (1%) as colorless crystalline solids. The structural assignments for the new
complexes were based upon spectral and analytical data and by X-ray crystal structure determinations
for tetr akisl N-rerr -butylaceta m ido )zircon iurn. tetrakis( N-isopropylacetamido)z ircon iurn, tetrakis( N-isopropylacetamido)hafnium. tetralds(N-methylacetamido)zirconium, and tetrakis(N-rert-butylformamido)
zirconium. These complexes are monomeric in the solid state, with eight-coordinate metal centers
surrounded by four K
2-N,O-amidate ligands. Six of the eight new complexes undergo sublimation on a
preparative scale from 130 to 140 °C at 0.05 Torr, with 84.5-95.8% sublimed recoveries and 0.68-3.06%
nonvolatile residues. Tetrakis(N-methylacetamido jzirconium and tetrakis(N-terr-butylformamido )zirconium decompose extensively upon attempted sublimation. Solid state decomposition temperatures for
the zirconium complexes range between 218 and 335 "C and 290-360 O( for the hafnium complexes.
Tetrakis(N-isopropylisobutyramido)zirconium, tetrakis(N-tert-butylacetamido)hafnium, and tetrakis(Nisopropylacetamido)hafnium exhibit the highest solid state decomposition temperatures in the series,
possess good volatility, and have useful properties for chemical vapor deposition and atomic layer
deposition precursors.
2017-01-01T00:00:00Z