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

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

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

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

Non-perturbative computation of double inclusive gluon production in the Glasma

The near-side ridge observed in A+A collisions at RHIC has been described as arising from the radial flow of Glasma flux tubes formed at very early times in the collisions. We investigate the viability of this scenario by performing a non-perturbative numerical computation of double inclusive gluon production in the Glasma. Our results support the conjecture that the range of transverse color screening of correlations determining the size of the flux tubes is a semi-hard scale, albeit with non-trivial structure. We discuss our results in the context of ridge correlations in the RHIC heavy ion experiments.Comment: 25 pages, 11 figures, uses JHEP3.cls V2: small clarifications, published in JHE

Liquid-gas phase transition in nuclear multifragmentation

The equation of state of nuclear matter suggests that at suitable beam energies the disassembling hot system formed in heavy ion collisions will pass through a liquid-gas coexistence region. Searching for the signatures of the phase transition has been a very important focal point of experimental endeavours in heavy ion collisions, in the last fifteen years. Simultaneously theoretical models have been developed to provide information about the equation of state and reaction mechanisms consistent with the experimental observables. This article is a review of this endeavour.Comment: 63 pages, 27 figures, submitted to Adv. Nucl. Phys. Some typos corrected, minor text change

Transient mTOR Inhibition Facilitates Continuous Growth of Liver Tumors by Modulating the Maintenance of CD133+ Cell Populations

The mammalian target of the rapamycin (mTOR) pathway, which drives cell proliferation, is frequently hyperactivated in a variety of malignancies. Therefore, the inhibition of the mTOR pathway has been considered as an appropriate approach for cancer therapy. In this study, we examined the roles of mTOR in the maintenance and differentiation of cancer stem-like cells (CSCs), the conversion of conventional cancer cells to CSCs and continuous tumor growth in vivo. In H-Ras-transformed mouse liver tumor cells, we found that pharmacological inhibition of mTOR with rapamycin greatly increased not only the CD133+ populations both in vitro and in vivo but also the expression of stem cell-like genes. Enhancing mTOR activity by over-expressing Rheb significantly decreased CD133 expression, whereas knockdown of the mTOR yielded an opposite effect. In addition, mTOR inhibition severely blocked the differentiation of CD133+ to CD133- liver tumor cells. Strikingly, single-cell culture experiments revealed that CD133- liver tumor cells were capable of converting to CD133+ cells and the inhibition of mTOR signaling substantially promoted this conversion. In serial implantation of tumor xenografts in nude BALB/c mice, the residual tumor cells that were exposed to rapamycin in vivo displayed higher CD133 expression and had increased secondary tumorigenicity compared with the control group. Moreover, rapamycin treatment also enhanced the level of stem cell-associated genes and CD133 expression in certain human liver tumor cell lines, such as Huh7, PLC/PRC/7 and Hep3B. The mTOR pathway is significantly involved in the generation and the differentiation of tumorigenic liver CSCs. These results may be valuable for the design of more rational strategies to control clinical malignant HCC using mTOR inhibitors

Resveratrol Inhibits Cancer Cell Metabolism by Down Regulating Pyruvate Kinase M2 via Inhibition of Mammalian Target of Rapamycin

Metabolism of cancer cells with pyruvate kinase M2 (PKM2) at its centre stage has assumed a prime significance in cancer research in recent times. Cancer cell metabolism, characterized by enhanced glucose uptake, production of lactate and anabolism is considered an ideal target for therapeutic interventions. Expression of PKM2 switches metabolism in favor of cancer cells, therefore, the present study was designed to investigate the hitherto unknown effect of resveratrol, a phytoalexin, on PKM2 expression and resultant implications on cancer metabolism. We observed that resveratrol down-regulated PKM2 expression by inhibiting mTOR signaling and suppressed cancer metabolism, adjudged by decreased glucose uptake, lactate production (aerobic glycolysis) and reduced anabolism (macromolecule synthesis) in various cancer cell lines. A contingent decrease in intracellular levels of ribose-5-phosphate (R5P), a critical intermediate of pentose phosphate pathway, accounted for a reduced anabolism. Consequently, the state of suppressed cancer metabolism resulted in decreased cellular proliferation. Interestingly, shRNA-mediated silencing of PKM2 inhibited glucose uptake and lactate production, providing evidence for the critical role of PKM2 and its mediation in the observed effects of resveratrol on cancer metabolism. Further, an over-expression of PKM2 abolished the observed effects of resveratrol, signifying the role of PKM2 downregulation as a critical function of resveratrol. The study reports a novel PKM2-mediated effect of resveratrol on cancer metabolism and provides a new dimension to its therapeutic potential