Kinetics of batch microbial degradation of phenols by indigenous Pseudomonas fluorescence

Abstract

ABSTRACT:The potential of various organisms to metabolize organic compounds has been observed to be a potentially effective means in disposing of hazardous and toxic wastes. Phenols and their compounds have long been recognized as one of the most recalcitrant and persistent organic chemicals in the environment. The bioremediation potential of an indigenous Pseudomonas fluorescence was studied in batch culture using synthetic phenol in water in the concentration range of (100 -500) mg/L as a model limiting substrate. The effect of initial phenol concentration on the degradation process was investigated. Phenol was completely degraded at different cultivation times for the different initial phenol concentrations. Increasing the initial phenol concentration from 100 mg/L to 500 mg/L increased the lag phase from 0 to 66 h and correspondingly prolonged the degradation process from 84 h to 354 h. There was decrease in biodegradation rate as initial phenol concentration increased. Fitting data into Monod kinetic model showed the inhibition effect of phenol The kinetic parameters have been estimated up to initial phenol concentration of 500 mg/ L. The r smax decreased and K s increased with higher concentration of phenol. The r smax has been found to be a strong function of initial phenol concentration. The culture followed substrate inhibition kinetics and the specific phenol consumption rates were fitted to Haldane, Yano and Koga, Aiba et al., Teissier and Webb models. Between the five inhibition models, the Haldane model was found to give the best fit. Therefore, the biokinetic constants estimated using these models showed good potential of the Pseudomonas fluorescence and the possibility of using it in bioremediation of phenol waste effluents.

Two-step treatment of harmful industrial wastewater: an analysis of microbial reactor with integrated membrane retention for benzene and toluene removal

“…According to the results obtained by balancing the RO module (Equation (21)), the interrelation between the permeate streams from the MF (Q 8 ) and RO (Q 6 ) modules also exerts an effect on the concentration c S, 6 . (21) A higher ratio of the streams corresponds to the lower concentration of pollutant in the stream leaving the system.…”

“…In expanded version of the model, the MF/UF membrane entirely separates the biomass (R X =1), hence (5) and the substrate is separated on the NF/RO module: (6) where R S -substrate retention coeffi cient Hence: Taking the stationary condition of the process:…”

“…Due to a limited range of concentrations, the kinetics of low water solubility substrates are usually fi rst order 3, 4 . However, even at these relatively low concentrations, substrate inhibition is observed for highly toxic compounds 5,6 . In such case, in CSTR two steady-states can occur at: (1) where: Y X/S -biomass yield coeffi cient, g X g S -1…”

Decontamination of 4-Chloro-2-Nitrophenol from Aqueous Solution by Graphene Adsorption: Equilibrium, Kinetic, and Thermodynamic Studies

“…Thus, development of suitable methods for the decontamination of phenols is necessary. Research has studied the removal of phenol from aqueous solutions, including advanced oxidation processes [5,6], biological degradation [7,8], ozonation [9,10], adsorption [11][12][13][14], etc. Among these methods, adsorption has been developed as a simple and cheap method to treat phenolic compounds.…”

Comparative Adsorption Of Dyes Unto Activated Carbon Prepared From Maize Stems And Sugar Cane Stems

“…Thus, uses of dye contaminated water without any treatment may cause adverse effect on human health, domestic animals, wildlife and on the environment. So it is necessary to treat or remove colour from the industrial effluent before discharge [2]. A wide range of various treatment methods (namely, ion exchange, biodegradation, oxidation, solvent extraction and adsorption) have been reported to be used for removal of organic pollutants from industrial effluents [3].…”