REMOVAL OF FLUORIDE USING NEEM LEAVES BATCH REACTOR: KINETICS AND EQUILIBRIUM STUDIES

 Objective: The aim of this paper is to study the fluoride removal efficiency of the neem leaves low-cost biosorbent for defluoridation of sewage wastewater.Methods: For finding the best operating condition for maximum removal of fluoride, batchwise experiments were performed at different contact times and keeping other parameters to be constant such as pH, initial fluoride concentration, and adsorbent dose. Various kinetic models such as intraparticle diffusion model, Bangham's model, and Elovich model had been investigated for determining the suitable adsorption mechanism. The rate of adsorption of fluoride on neem leaves has been determined by pseudo-first-order and pseudo-second-order rate models.Results: The adsorption kinetics rate and mechanism was best described by the pseudo-second-order model and Bangham's model, respectively. The optimum pH, initial concentration, adsorbent dose, and contact time were found to be 7, 20 mg/L, 10 g/L, and 40 min, respectively, for which there was maximum fluoride removal.Conclusion: The result obtained from the experiments show that the neem leaves have been proved to be a low-cost biosorbent for the defluoridation of the sewage wastewater and have high fluoride removal efficiency

COMPARING FLUORIDE REMOVAL KINETICS OF ADSORPTION PROCESS FROM AQUEOUS SOLUTION BY BIOSORBENTS

ABSTRACTObjective: In this study, we observed the defluoridation capacity of groundnut shell and Citrus limetta (commonly known as sweet lime) and aims atcomparison of their defluoridation capacity.Methods: Batch experiments were carried out for this investigation. To find out the best operating conditions for maximum fluoride removal, wevaried the contact time by keeping others parameters to be constant and observed their effects on defluoridation capacity. In this study to followadsorption process, we used various kinetic models, namely, Elovich equation, Weber and Morris intra-particle diffusion model, Bangham's porediffusion model, and the pseudo first and second order equations. We also calculated and discussed the effects of various kinetic parameters such ascorrelation coefficients, equilibrium adsorption capacities and rate constant.Results: The hand-in-hand relationship between intra-particle diffusion model and Elovich equation indicates a major role of pore diffusion processin adsorption mechanism. Furthermore, the rate kinetics is best described by pseudo second order model for both the biosorbents.Conclusion: From the performed experiments, it was found that Citrus limetta peel has more defluoridation capacity in comparison of groundnutshell in all manners.Keywords: Adsorption kinetics, Adsorption, Biosorbent, Ground nut shell, Citrus limetta peel

A COMPARISON BETWEEN BIOSORPTION AND BIOACCUMULATION OF FLUORIDE FROM WASTE WATER.

 Objective: The comparison between the properties of two removal methods viz. adsorptive removal (biosorption) and simultaneous adsorption and bioaccumulation (SAB) of fluoride from waste water was investigated.Methods: In the present study, bioaccumulation study was done on Sweet Lemon peel. Acinetobacter baumannii (Mtcc no-11451) is a water living microorganism which survives in waste water. Microorganism (Acinetobacter baumannii (Mtcc no-11451)) immobilized on the surface of Sweet Lemon peel. The size of microorganism is greater than the pore size of adsorbent. Active sites of the adsorbent are blocked due to immobilization of microorganism on the surface of adsorbent. Different optimizing parameters are studied during the experiments like adsorbent dose, pH, initial concentration and contact time for bio bioaccumulation process.Results: It was observed that adsorption and bioaccumulation process execute simultaneously but mainly bioaccumulation is responsible for removal of fluoride. The removal efficiency of fluoride sees a drastic increase from 59.59 % to 99.49 % in optimum conditions. It is to be noted that simple adsorption process removal efficiency was 95.795 % at optimum time (60 min), pH 4.0 and dose 10 g/l. Adsorption isotherm parameters are well fitted for Freundlich whereas simple adsorption follow Langmuir isotherm model.Conclusion: The removal of fluoride occurred due to the accumulation by bacteria. Kinetic result revealed that bioaccumulation is a slower process. Bioaccumulation process increase the removal efficiency but it is very time consuming and costly as compare to the simple adsorption process

ADSORPTION OF FLUORIDE FROM INDUSTRIAL WASTEWATER IN FIXED BED COLUMN USING JAVA PLUM (SYZYGIUM CUMINI)

ABSTRACTObjective: The quality of drinking water is important for public safety and quality of life. Thus, providing every person on earth safe drinking waterseems to be the biggest challenge in front of mankind. For this purpose, here we have investigated the fluoride removal capacity of java plum.Methods: In this study, removal of fluoride from industrial wastewater using fixed-bed reactor adsorption techniques by java plum seed (Syzygiumcumini) was investigated. Fixed-bed column experiments were carried out for different bed depths, influent fluoride concentrations, and various flowrates. The Thomas model and bed depth service time model were applied to the experimental results. Both model predictions verify the experimentaldata for all the process parameters studied, indicating that the models were suitable for java plum (S. cumini) seeds (Biosorbent) fix-bed columndesign.Results: The empty bed residence time (EBRT) model optimizes the EBRT, and the Thomas model showed that the adsorption capacity is stronglydependent on the flow rate, initial fluoride concentration, and bed depth and is greater under conditions of a lower concentration of fluoride, lowerflow rate, and higher bed depth.Conclusion: The experimental results were encouraging and indicate that java plum (S. cumini) seed is a feasible option to use as a biosorbent toremove fluoride in a fixed bed adsorption process.Keywords: Adsorption, Column experiment, Thomas model, Empty bed residence time, Java plum

TREATMENT OF FLUORIDE BEARING CONTAMINATED WATER USING SIMULTANEOUS ADSORPTION AND BIODEGRADATION IN A LABORATORY SCALE UP: FLOW BIO-COLUMN REACTOR BY JAVA PLUM SEED

ABSTRACTObjective: Here, we aimed for the treatment of fluoride bearing contaminated water using simultaneous adsorption and biodegradation in a biocolumnreactor by using java plum seed.Methods: We immobilized Acinetobacter baumannii bacteria on the java plum seed in the bio-column reactor. The water used contained a sample offluoride with concentration of 20 mg/L. The bed depth service time design model and empty bed residence time were used to analyze the performance thebio-column. We examined and observed closely the effect of different operating parameters such as flow rate of bed depth and initial concentration on thissimplified bio-column reactor design model. Desorption experiment was conducted to evaluate the possibilities of regeneration and to reutilize of media.Results: We observed that the bio-column reactor is capable to reduce the concentration of the pollutants in the effluent water below their permissiblelimit. Reduction in DO along the bed height of the reactor was also observed, which supports the aerobic nature of the bacteria.Conclusion: The experimental results were encouraging and indicate that java plum (Syzygium cumini) seed is a feasible option to use as a biosorbentto remove fluoride in the bio-column reactor.Keywords: Bio-reactor, Simultaneous adsorption and biodegradation, Flow rate, Acinetobacter baumannii MTCC 11451, Physicochemical adsorption,Bed depth service time, Empty bed residence time

EXPLORING DEFLUORIDATION CAPACITY OF TURMERIC ON INDUSTRIAL SEWAGE

ABSTRACTObjective: This research was carried out for developing a low-cost agro-based biosorbent for defluoridation of wastewater. Here, we investigated thedefluoridation capacities of simple turmeric and MnO2-coated turmeric.Methods: The defluoridation capacity of turmeric had been investigated through batch sorption techniques. In the batch sorption technique, theeffect of various parameters such as adsorbent dose, initial fluoride concentration, and pH had been studied, and these parameters are optimized formaximum fluoride removal efficiency. Each adsorbent was characterized using various techniques such as Fourier transform infrared spectroscopy,scanning electron micrograph, and Energy Dispersive Analysis of1 X-Ray. The adsorption kinetics had been studied through different kinetics modelssuch as intra-particle diffusion model and pseudo-first order model. For adsorption equilibrium, we studied the conventional equilibrium modelssuch as Langmuir isotherm model and Freundlich isotherm model.Results: The result of the performed experiments shows that for turmeric and MnO-coated turmeric, the values of pH, adsorbent dose, initialconcentration, and contact time were 7 and 6, 12 and 14 g/l, 20 and 20 mg/l, 60 and 75 minutes at which optimum defluoridation of about 89.9% and94.34% occurs, respectively.Conclusion: The result obtained from the experiments shows that the MnOKeywords: Defluoridation, Turmeric, MnO222 coating has increased the defluoridation capacity of the turmeric.-coated turmeric, Fourier transform infrared spectroscopy, Scanning electron micrograph, EnergyDispersive Analysis of X-Ray, Langmuir isotherm, Freundlich isotherm

A COMPARISON BETWEEN BIOSORPTION AND BIOACCUMULATION OF FLUORIDE FROM WASTE WATER.

 Objective: The comparison between the properties of two removal methods viz. adsorptive removal (biosorption) and simultaneous adsorption and bioaccumulation (SAB) of fluoride from waste water was investigated.Methods: In the present study, bioaccumulation study was done on Sweet Lemon peel. Acinetobacter baumannii (Mtcc no-11451) is a water living microorganism which survives in waste water. Microorganism (Acinetobacter baumannii (Mtcc no-11451)) immobilized on the surface of Sweet Lemon peel. The size of microorganism is greater than the pore size of adsorbent. Active sites of the adsorbent are blocked due to immobilization of microorganism on the surface of adsorbent. Different optimizing parameters are studied during the experiments like adsorbent dose, pH, initial concentration and contact time for bio bioaccumulation process.Results: It was observed that adsorption and bioaccumulation process execute simultaneously but mainly bioaccumulation is responsible for removal of fluoride. The removal efficiency of fluoride sees a drastic increase from 59.59 % to 99.49 % in optimum conditions. It is to be noted that simple adsorption process removal efficiency was 95.795 % at optimum time (60 min), pH 4.0 and dose 10 g/l. Adsorption isotherm parameters are well fitted for Freundlich whereas simple adsorption follow Langmuir isotherm model.Conclusion: The removal of fluoride occurred due to the accumulation by bacteria. Kinetic result revealed that bioaccumulation is a slower process. Bioaccumulation process increase the removal efficiency but it is very time consuming and costly as compare to the simple adsorption process

REMOVAL OF FLUORIDE USING NEEM LEAVES BATCH REACTOR: KINETICS AND EQUILIBRIUM STUDIES

 Objective: The aim of this paper is to study the fluoride removal efficiency of the neem leaves low-cost biosorbent for defluoridation of sewage wastewater.Methods: For finding the best operating condition for maximum removal of fluoride, batchwise experiments were performed at different contact times and keeping other parameters to be constant such as pH, initial fluoride concentration, and adsorbent dose. Various kinetic models such as intraparticle diffusion model, Bangham's model, and Elovich model had been investigated for determining the suitable adsorption mechanism. The rate of adsorption of fluoride on neem leaves has been determined by pseudo-first-order and pseudo-second-order rate models.Results: The adsorption kinetics rate and mechanism was best described by the pseudo-second-order model and Bangham's model, respectively. The optimum pH, initial concentration, adsorbent dose, and contact time were found to be 7, 20 mg/L, 10 g/L, and 40 min, respectively, for which there was maximum fluoride removal.Conclusion: The result obtained from the experiments show that the neem leaves have been proved to be a low-cost biosorbent for the defluoridation of the sewage wastewater and have high fluoride removal efficiency