Biomedical subjects

Gurusamy Annadurai

Publications and source records attributed to Gurusamy Annadurai.

4 recordsLinked to original sources

PubMed2002

Use of cellulose-based wastes for adsorption of dyes from aqueous solutions.

Low-cost banana and orange peels were prepared as adsorbents for the adsorption of dyes from aqueous solutions. Dye concentration and pH were varied. The adsorption capacities for both peels decreased in the order methyl orange (MO) > methylene blue (MB) > Rhodamine B (RB) > Congo red (CR) > methyl violet (MV) > amido black 10B (AB). The isotherm data could be well described by the Freundlich and Langmuir equations in the concentration range of 10-120 mg/l. An alkaline pH was favorable for the adsorption of dyes. Based on the adsorption capacity, it was shown that banana peel was more effective than orange peel. Kinetic parameters of adsorption such as the Langergren rate constant and the intraparticle diffusion rate constant were determined. For the present adsorption process intraparticle diffusion of dyes within the particle was identified to be rate limiting. Both peel wastes were shown to be promising materials for adsorption removal of dyes from aqueous solutions.

Adsorption↗

PubMed2002

Microbiological degradation of phenol using mixed liquors of Pseudomonas putida and activated sludge.

This work investigated the biodegradation potential of phenol using mixed liquors of Pseudomonas putida (ATCC 31800) and activated sludge. Experiments were made as a function of solution pH (6-10), temperature (30-36 degrees C), nitrogen source (NH4)2SO4 (0.5-0.8 g/l), and carbon source glucose (0.5-0.8 g/l). Response surface methodology by the Box-Behnken model was used to examine the role of four process factors on phenol degradation. It was shown that a second-order polynomial regression model could properly interpret the experimental data with an R2-value of 0.9997 and an F-value of 3605.45, based on which the maximum degradation of phenol was estimated up to 80.1% within the range examined. Interactions between process parameters and each significance effect on phenol degradation were also discussed.

Biodegradation, Environmental↗

PubMed2002

Factor optimization for phenol removal using activated carbon immobilized with Pseudomonas putida.

Removal efficiency of phenol from aqueous solutions was measured using a suspended culture of Pseudomonas putida (ATCC 3180) or the activated carbon on which the microorganisms were immobilized. Experiments were performed as a function of pH (7-9), temperature (30-36 degrees C), and concentrations of glucose (0.5-0.7 g/l) and ammonium sulfate (0.5-0.7 g/l). The Box-Behnken design was applied in a second-degree quadratic, polynomial regression model to identify the significant effects and the interactions among the above four factors. Based on response curve method the conditions for maximizing phenol removal (initially 0.2 g/l) were recognized as pH 7, temperature 30 degrees C, glucose 0.6 g/l, and ammonium sulfate 0.6 g/l. The inhibition effect of carbon and nitrogen sources beyond a concentration of 0.6 g/l on phenol removal was obvious.

Biodegradation, Environmental↗

PubMed2002

Biodegradation and adsorption of phenol using activated carbon immobilized with Pseudomonas putida.

This paper examined the removal efficiency of phenol from aqueous solution using a suspended culture of Pseudomonas putida (ATCC 3180) or the activated carbon on which the microorganism was immobilized. The kinetics of phenol degradation by immobilized and pure cells was studied. Experiments were performed at various phenol concentrations (0.1-0.4 g/L), pH, temperature (30-36 degrees C), and concentrations of glucose (0.5-0.7 g/L) and (NH4)2SO4 (0.5-0.7 g/L). The presence of activated carbon markedly enhanced the degradation efficiency, showing its ability of protecting microbes from confronting shock loads of organic pollutants. Degradation rate increased with increasing substrate concentration and decreased after reaching a maximum, indicating substrate-inhibition kinetics. In addition, the degradation rate for immobilized cells was much higher than that of free cells. The inhibition effect for phenol degradation was described by the Andrews model. The kinetic parameters were also determined.

Adsorption↗