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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
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.
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.
Chemical Industry and Chemical Engineering Quarterly , 2011,
Abstract: TIn this work, removal of malachite green (MG) from aqueous solution using a low cost adsorbent, tamarind seed, was investigated. The adsorbent was characterized using SEM, BET surface area analyzer, and FT-IR. Decolourization of malachite green was studied as a function of different adsorption parameters such as temperature, adsorbent dose, contact time, adsorbent size and agitation speed. These parameters were optimized using response surface methodology (RSM). The significance of different adsorption parameters along with their combined effect on the adsorption process has been established through a full 50 factorial design. Langmuir, Freundlich, Redlich Petersen, Dubnin Redushkevich and Tempkin adsorption isotherm equations were used in the equilibrium modeling. Experimental data follows the Langmuir adsorption isotherm. The adsorption process follows a pseudo first order and intra-particle diffusion is found to be the rate-controlling step.
Uptake of Cationic Dyes from Aqueous Solution by Biosorption Using Granulized Annona squmosa Seed  [PDF]
T. Santhi,S. Manonmani
Journal of Chemistry , 2009, DOI: 10.1155/2009/472703
Adsorption of Malachite Green from Aqueous Solutions onto Rice Husks: Kinetic and Equilibrium Studies  [PDF]
V. M. Muinde, J. M. Onyari, B. Wamalwa, J. Wabomba, R. M. Nthumbi
Journal of Environmental Protection (JEP) , 2017, DOI: 10.4236/jep.2017.83017
Abstract: A study was done to evaluate the removal of a cationic dye from simulated waste water onto rice husks (RH). Spectroscopic methods such as FTIR and SEM/EDX were used for adsorbent characterization. Experimental dependency on solution pH, initial dye concentration, agitation speed, adsorbentparticle size, temperature of the solution and contact time was evaluated. The adsorption data was tested using both Langmuir and Freundlich isotherms. The data fitted well into Langmuir isotherm model with a monolayer adsorption capacity of 6.5 mg/g. Further, the separation factor (RL) value was less than unity indicating a favorable adsorption process. Adsorption kinetics was determined using pseudo-first-order, pseudo-second-order and intra-particle diffusion models. The results showed that the adsorption of malachite green onto rice husks followed pseudo-second-order model with a determination coefficient of 0.986. This work has revealed that rice husks have a great potential to sequester cationic dyes from aqueous solutions and therefore it can be utilized to clean contaminated effluents.
Fast Removal of Malachite Green by Adsorption on Rice Husk Activated Carbon
Y.C. Sharma, B. SinghUma
The Open Environmental Pollution & Toxicology Journal , 2009, DOI: 10.2174/1876397900901010074]
Abstract: Application of activated carbon developed from rice husk, an agricultural waste product has been investigated for the removal of malachite green from aqueous solutions and wastewaters. Batch adsorption experiments were carried out for the removal of malachite green from aqueous solutions onto rice husk activated carbon. Effect of important parameters namely initial concentration of dye and contact time, and temperature was studied on removal of the dye. The removal increased from 93.75 to 94.91% by decreasing the initial concentration from 100 to 60 mg/l. Equilibrium data were fitted to Freundlich and Langmuir isotherm equations and the isotherm constants were determined. The monolayer adsorption capacity of rice husk activated carbon for adsorption of the dye was found to be 63.85 mg/g at room temperature.
Removal of malachite green from water by Firmiana simplex wood fiber
Pan,Xiangliang; Zhang,Daoyong;
Electronic Journal of Biotechnology , 2009,
Abstract: this study shows that wood fiber of phoenix tree (firmiana simplex) is an effective adsorbent for malachite green (mg). mg sorption behavior onto the wood adsorbent was investigated in this study. basic condition was favorable for mg adsorption to the adsorbent. the pseudo second order equation well described mg adsorption onto the wood adsorbent. the freundlich isotherm could describe the sorption data. the positive value of δh0 showed that adsorption of malachite green onto the wood adsorbent was endothermic. the negative values of δg at various temperatures indicate the spontaneous nature of the adsorption process.
Thermodynamic and Isotherm Analysis on the Removal of Malachite Green Dye Using Thespesia Populnea Bark  [PDF]
R. Prabakaran,S. Arivoli
Journal of Chemistry , 2012, DOI: 10.1155/2012/629089
Abstract: Activated carbon was synthesized from Thespesia Populnea Bark, a low cost material, by sulphuric acid activation; it was tested for its ability to eliminate malachite green in aqueous solution. The parameters studied included contact time, initial dye concentration, carbon dose, pH and temperature. The adsorption followed first order rate equation. In addition, it was found that the adsorption process was described by Freundlich and Langmuir isotherm models. Those models were applied to the equilibrium data. The absorption capacities (Qm) obtained from the Langmuir isotherm plots were 349.20, 365.43, 476.44, and 389.96 mg/g at 30°, 40°, 50°, and 60°C, respectively, at an initial pH 6.0. The temperature variation study showed that the malachite green dye absorption was endothermic and spontaneous with increased randomness at the solid solution interface. The thermodynamic parameters like ?H°, ?S°, and ?G° were calculated from the slope and intercept of the linear plots.
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.
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