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Kinetics And Isotherm Studies On Cationic Dyes Adsorption Onto Annona Squmosa Seed Activated Carbon
T. Santhi,S. Manonmani,T.Smitha
International Journal of Engineering Science and Technology , 2010,
Abstract: The use of low - cost, locally available and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbon prepared from the Annona squmosa seed for the removal of methylene blue (MB) , methyl red (MR) and malachite green (MG) dyes from simulated wastewater. Adsorption of MB, MR and MG dyes on the Annona squmosa seed showed highest values at around pH 7.0, and followed second –order kinetic with intraparticle diffusion as one of the rate determining steps. The adsorption-equilibrium was represented with Langmuir, Freundlich, Dubinin-Radushekevich and Tempkin isotherms. Activated carbon developed from the Annona squmosa seed can be an attractive option for dyes removal from diluted industrial effluents.
Removal of methyl red from aqueous solution by activated carbon prepared from the Annona squmosa seed by adsorption  [cached]
T Santhi,S. Manonmani,T. Smitha
Chemical Engineering Research Bulletin , 2010, DOI: 10.3329/cerb.v14i1.3767
Abstract: The use of low-cost, locally available, highly efficiencient and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbon prepared from the Annona squmosaseed for the removal of methyl red (MR) dye from simulated wastewater. The effects of different system variables, adsorbent dosage, initial dye concentration, pH and contact time were investigated and optimal experimental conditions were ascertained. The results showed that as the amount of the adsorbent increased, the percentage of dye removal increased accordingly. Optimum pH value for dye adsorption was 7.0. Maximum dye was sequestered within 50 min of the start of every experiment. The adsorption of methylene blue followed the pseudo-second –order rate equation and fits the Langmuir, Freundlich, Dubinin-Radushekevich (D-R) and Tempkin equations well. The maximum removal of MR was obtained at pH 7 as 82.81% for adsorbent dose of 0.2 g/ 50 mL and 25 mg L -1 initial dye concentration at room temperature. Furthermore, adsorption kinetics of MR was studied and the rate of adsorption was found to conform to pseudo-second –order kinetics with a good correlation (R2 > 0.99) with intraparticle diffusion as one of the rate determining steps. Activated carbon developed from the Annona squmosa seed can be an attractive option for dye removal from diluted industrial effluents since test reaction made on simulated dyeing wastewater showed better removal percentage of MR. Keywords: Annona squmosa, Adsorption, Wastewater, Methyl red, Kinetics, Activated carbon DOI = 10.3329/cerb.v14i1.3767 Chemical Engineering Research Bulletin 14 (2010) 11-18
Removal of malachite green from aqueous solution by activated carbon prepared from the Annona squmosa seed by adsorption  [cached]
T. Santhi,S. Manonmani,T. Smith
Orbital : the Electronic Journal of Chemistry , 2010,
Abstract: The use of low -cost, locally available, highly efficient and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbon prepared from the Annona squmosa seed for the removal of malachite green (MG) dye from simulated wastewater. The effects of different system variables, adsorbent dosage, initial dye concentration, pH and contact time were investigated and optimal experimental conditions were ascertained. The results showed that as the amount of the adsorbent is increased, the percentage of dye removal increase accordingly. Optimum pH value for dye adsorption was 7.0. Maximum dye was sequestered within 50 min from the start of every experiment. The adsorption of malachite green followed the pseudo-second –order rate equation and fits the Langmuir, Freundlich, Dubinin-Radushekevich (D-R) and Tempkin equations well. The maximum removal of MG was obtained at pH 7 as 86.11% for adsorbent dose of 0.2 g/ 50 mL and 25 mg L -1 initial dye concentration at room temperature. Furthermore, adsorption kinetics of MG was studied and the rate of adsorption was found to conform to pseudo-second –order kinetics with a good correlation (R2 > 0.99) with intraparticle diffusion as one of the rate determining steps. Activated carbon developed from the Annona squmosa seed can be an attractive option for dye removal from diluted industrial effluents since test reaction made on simulated dyeing wastewater showed better removal percentage of MG.
Toxicological Evaluation of Annotemoyin-1 Isolated from Annona squmosa Linn. on Long Evan?s Rats  [PDF]
Mst. Shahnaj Parvin,M. Ekramul Islam,Md. Motiur Rahman,Md. Ekramul Haque
Pakistan Journal of Biological Sciences , 2003,
Abstract: The potential toxicity of annotemoyin-1 isolated from the seeds of Annona squamosa Linn., collected from the relevant areas of Bangladesh was evaluated on Long Evan`s rats. Annotemoyin-1 (100 μgm and 200 μgm) was administered daily for 14 days and the effects on body weight, hematological and biochemical parameters of the blood and histopathological parameters of heart, kidney, lungs and liver were studied. There was no significant difference between weight gain in rats receiving annotemoyin-1 and control rats. The changes of hematological and biochemical parameters were statistically insignificant. No abnormalities were found in the histopathological parameters of heart, kidney, lungs and liver of the experimental groups of rats when compared with control groups of rats. From this study, it was inferred that annotemoyin-1 (100 μgm and 200 μgm) over 14 days, had no toxic effect on rats.
A Biosorption Isotherm Model for the Removal of Reactive Azo Dyes by Inactivated Mycelia of Cunninghamella elegans UCP542  [PDF]
Sandra T. Ambrósio,José C. Vilar Júnior,Carlos A. Alves da Silva,Kaoru Okada,Aline E. Nascimento,Ricardo L. Longo,Galba M. Campos-Takaki
Molecules , 2012, DOI: 10.3390/molecules17010452
Abstract: The biosorption of three reactive azo dyes (red, black and orange II) found in textile effluents by inactive mycelium of Cunninghamella elegans has been investigated. It was found that after 120 hours of contact the adsorption led to 70%, 85%, 93% and 88% removal of reactive orange II, reactive black, reactive red and a mixture of them, respectively. The mycelium surface was found to be selective towards the azo dyes in the following order: reactive red > reactive black > orange II. Dye removal from a mixture solution resulted in 48.4 mg/g retention by mycelium and indicated a competition amongst the dyes for the cellular surface. A Freundlich adsorption isotherm model exhibited a better fit, thus suggesting the presence of heterogeneous binding sites. Electrondense deposits observed on the mycelium ultrastructure suggest that the dyes are mainly retained under the cellular surface of the inactive biomass of C. elegans.
BIOSORPTION IN TREATMENT OF WASTE WATER  [cached]
Lavinia Tofan,Daniela Suteu,Laura Bulgariu,Ovidiu Toma
Analele ?tiin?ifice Ale Universit??ii Alexandru Ioan Cuza din Ia?i,Sectiunea II A : Genetica si Biologie Moleculara , 2003,
Abstract: The imperative of environment protection brings out the biomass use in recovery of toxic or valuable metals from diluted effluents. This fact is due to biosorption, which is more efficient in retention of cations present at low concentrations in aqueous solutions, that the conventional treatment, involving reduced energetic consumptions too.
Biosorption of Basic Dyes Using Sewage Treatment Plant Biosolids  [PDF]
Md. Zahangir Alam
Biotechnology , 2004,
Abstract: Studies on the removal of three basic dyes (Basic Blue 3, Basic Red 22, Basic Black 9) from aqueous solutions by adsorption on Sewage Treatment Plant (STP) biosolids (sludge) as an adsorbent were carried out with an aim to obtain information on treating effluents from textile and/or dye industries. A series of experiments were undertaken in a batch adsorption technique to access the effect of the process variables i.e. initial dye concentration, contact time, initial pH, adsorbent dose, temperature and agitation rate. The adsorption capacity of basic dyes was higher (22-24 mg g-1) with the lower values of the temperature (25-30 C), adsorbent dosage (0.5-0.75% w/v), higher values of the initial pH (8-9) and agitation rate (150-200 rpm). The equilibrium in the solution was observed within 2 h of operation. The equilibrium isotherm for each dye was determined to describe the biosorption processes. The results showed that the equilibrium data were fitted by both of the Langmuir and Freundlich isotherms while Freundlich isotherms was slightly better fitted for Basic Blue 3 and Langmuir was for the Basic Black 9 in terms of regression coefficients (R2).
Equilibrium and Spectroscopic Studies on Biosorption of Mercury by Algae Biomass
Abbas Rezaee,Bahman Ramavandi,Faezeh Ganati
Pakistan Journal of Biological Sciences , 2006,
Abstract: Mercury has been used in many industries and the removal of mercury ions from waste waters is significant. Biosorption equilibrium of mercury ions to algae biomass was studied in a batch system with respect to temperature and initial metal ion concentration. Langmuir isotherm models was applied to experimental equilibrium data of mercury biosorption. The maximum adsorption of mercury ions on algae biomass was observed at pH 4.0. The biosorption of mercury ions by the algae biomass increased as the initial concentration of the mercury ions increased in the biosorption medium. Biosorption equilibrium was established in about 60 min and the equilibrium was well described by the Langmuir biosorption isotherms. The biomass could be regenerated using 0.1 M HCl, with up to 98% recovery, which allowed the reuse of the biomass in two biosorption-desorption cycles without any considerable loss of biosorption capacity. The functional groups involved in mercury biosorption were identified using spectroscopy analysis. Spectroscopic analysis of algal biomass revealed the presence of amino, carboxyl, hydroxyl and carbonyl groups, which were responsible for biosorption of mercury ions.
Alkaloids from Annona dioica
Santos, Paulo R. D. dos;Morais, Anselmo A.;Braz-Filho, Raimundo;
Journal of the Brazilian Chemical Society , 2003, DOI: 10.1590/S0103-50532003000300009
Abstract: from the ethanolic extract of the wood of annona dioica were isolated the known 1-aza-4-methylanthraquinone, lasiodiplodin, liriodenine, a mixture of 1-aza-5,9,10-trimethoxy-4-methyl-2-oxo-1,2-dihydroanthracene and 1-aza-8,9,10-trimethoxy-4-methyl-2-oxo-1,2-dihydroanthracene (geovanine) and the new alkaloid 1,2-methylenedioxy-6a,7-dehydroaporphine-4(s )-(4-hydroxy-3,5-dimethoxyphenyl)-3,4-dihydro-2(1h)-pyridinone. the structures of these natural products were elucidated on the basis of their spectral data, including noe experiments and homonuclear 1h-1h-cosy e heteronuclear 1h-13c-cosy-njch (hmqc, n=1 and hmbc, n=2 and 3) 2d-shift-correlated nmr spectra.
Alkaloids from Annona dioica  [cached]
Santos Paulo R. D. dos,Morais Anselmo A.,Braz-Filho Raimundo
Journal of the Brazilian Chemical Society , 2003,
Abstract: From the ethanolic extract of the wood of Annona dioica were isolated the known 1-aza-4-methylanthraquinone, lasiodiplodin, liriodenine, a mixture of 1-aza-5,9,10-trimethoxy-4-methyl-2-oxo-1,2-dihydroanthracene and 1-aza-8,9,10-trimethoxy-4-methyl-2-oxo-1,2-dihydroanthracene (geovanine) and the new alkaloid 1,2-methylenedioxy-6alpha,7-dehydroaporphine-4(S )-(4-hydroxy-3,5-dimethoxyphenyl)-3,4-dihydro-2(1H)-pyridinone. The structures of these natural products were elucidated on the basis of their spectral data, including NOE experiments and homonuclear 1H-1H-COSY e heteronuclear 1H-13C-COSY-nJ CH (HMQC, n=1 and HMBC, n=2 and 3) 2D-shift-correlated NMR spectra.
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