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phenol-removals
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Removal of phenols with encapsulated horseradish peroxidase in calcium alginate
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 28, Issue 2 , 2009 , Pages 43-49 ; 10219986 (ISSN) ; Nejati, S ; Sharif University of Technology
2009
Abstract
Horseradish peroxidase was encapsulated in calcium alginate for the purpose of phenol removal. Considering enzyme encapsulation efficiency, retention activity and enzyme leakage of the capsules, the best gelation condition was found to be 1 % w/v of sodium alginate solution and 5.5 % w/v of calcium chloride hexahydrate. Upon immobilization, pH profile of enzyme activity changes as it shows higher value at basic and acidic solution. Besides, for each phenol concentration there would be an enzyme concentration which going further than this value has no significant effect on phenol removal. Investigation into time course of phenol removal for both encapsulated and free enzyme showed that...
Immobilization of Enzymes to Nanoparticles for use in Wastewater Treatment
, M.Sc. Thesis Sharif University of Technology ; Alemzadeh, Iran (Supervisor)
Abstract
Nowadays , application of enzymes as biocatalysts in wastewater treatment processes is increasing. It is economically important to reuse enzymes and increase their stability in these types of processes. Therefore, was immobilization of enzymes and using them in wastewater treatment have a great importance.In this project, Horseradish peroxidase enzyme, whose effect on phenol removal reactions in other studies has been proven before, was immobilized on the alginate-coated magnetic nanoparticles, to investigate the effect of immobilization on the stability and function of this enzyme for phenol removal. The enzyme was immobilized at the temperature of 25 ° C and pH = 8, according to the data...
Phenols removal by immobilized horseradish peroxidase
, Article Journal of Hazardous Materials ; Volume 166, Issue 2-3 , 2009 , Pages 1082-1086 ; 03043894 (ISSN) ; Nejati, S ; Sharif University of Technology
2009
Abstract
Application of immobilized horseradish peroxidase (HRP) in porous calcium alginate (ca-alginate) for the purpose of phenol removal is reported. The optimal conditions for immobilization of HRP in ca-alginate were identified. Gelation (encapsulation) was optimized at 1.0% (w/v) sodium alginate in the presence of 5.5% (w/v) of calcium chloride. Upon immobilization, pH profile of enzyme activity changes as it shows higher value at basic and acidic solution. Increasing initial phenol concentration results in a decrease in % conversion. The highest conversion belongs to phenol concentration of 2 mM. Investigation into time course of phenol removal for both encapsulated and free enzymes showed...
Simulation of Phenol Biodegradation by Pseudomonas Putida in a Continuous Stirred Biofilm Reactor
,
M.Sc. Thesis
Sharif University of Technology
;
Yaghmaei, Soheila
(Supervisor)
;
Askaripour, Hossein
(Supervisor)
Abstract
The use of microorganisms to remove or produce a substace is a fundamental part of biotechnology. An example is the bioreactors for phenol removal in wastewater. Biological processes are commonly done in batch reactors in which suspended cells grow in the liquid phase. The batch process needs alternate reactor washes and alternate cell cultivation, which leades to a longer time constant for for each batch. If these reactors operate in continuous conditions, the cells will leave the reactor in liquid flow, and high cell concentrations will be impossible. The biofilm layer makes a batch phase, so the liquid phase flows in and out continuously, but the cells in the biofilm layer stay in the...
The comparision of Coprinus cinereus peroxidase enzyme and TiO 2 catalyst for phenol removal
, Article Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering ; Volume 48, Issue 3 , 2013 , Pages 300-307 ; 10934529 (ISSN) ; Tavakoli, O ; Sarrafzadeh, M. H ; Kariminia, H. R ; Sharif University of Technology
2013
Abstract
This article investigates phenol removal from an aqueous solution by using enzymatic and photocatalytic methods and the efficiency of these methods has been compared. In enzymatic and photocatalytic methods, Coprinus cinereus, peroxidase enzyme and commercial TiO2 powders (Degussa P-25) in aqueous suspension were used, respectively, in ambient temperature. The effects of different operating parameters such as duration of process, catalyst dosage or enzyme concentration, pH of the solution, initial phenol concentration and H2O2 concentration on both processes were examined. In enzymatic method, efficiency of degradation reached 100% within 5min, while in the photocatalytic method, the...
Removal of chlorophenolic derivatives by soil isolated ascomycete of Paraconiothyrium variabile and studying the role of its extracellular laccase
, Article Journal of Hazardous Materials ; Volume 209-210 , 2012 , Pages 199-203 ; 03043894 (ISSN) ; Movahednia, M. M ; Yaghmaei, S ; Tabatabaei Sameni, M ; Rastegar, H ; Sadighi, A ; Faramarzi, M. A ; Sharif University of Technology
2012
Abstract
The ability of Paraconiothyrium variabile, a laccase producing ascomycete recently isolated from soil, was studied to eliminate chlorophenol derivatives in submerged culture medium. Among the tested compounds, ρ-chlorophenol (ρ-CP) and pentachlorophenol (PCP) were found to have minimum and maximum toxic effects, respectively, on the growth of the microorganism and at the same time high and low bioelimination percentages. The fungal strain was able to remove 86% of ρ-CP (with initial concentration of 40mgl -1) and 56% of 2,4-dichlorophenol (2,4-DCP; with same concentration as ρ-CP) after 9 days of incubation while no elimination was observed in the presence of 2,4,6-trichlorophenol...