The Experts below are selected from a list of 1134 Experts worldwide ranked by ideXlab platform

Dinesh Kumar - One of the best experts on this subject based on the ideXlab platform.

Naba Kumar Mondal - One of the best experts on this subject based on the ideXlab platform.

  • Adsorption of fluoride from aqueous solution by a new low-cost adsorbent: thermally and chemically activated coconut fibre dust
    Clean Technologies and Environmental Policy, 2015
    Co-Authors: Ria Bhaumik, Naba Kumar Mondal
    Abstract:

    Fluoride is a persistent and non-Biodegradable Pollutant that accumulates in soil, plants, wildlife and human beings. Therefore, knowledge of its removal, using the best technique with optimum efficiency, is needed. In the present study, the potential usage of coconut fibre ( Cocos nucifera ), which is an agricultural waste, in the adsorption of fluoride from aqueous solutions was evaluated with respect to various experimental parameters including pH, adsorbent dose, contact time, agitation speed, initial fluoride concentration and temperature. The objective is to expand upon research of new and existing fluoride removal technologies or promote a new, alternative process. In the present study, the maximum adsorption capacity was recorded as 12.66, 25.64 and 38.46 mg/g for CFD-1, CFD-2 and CFD-3, respectively. From the kinetic study, it was found that fluoride adsorption by coconut fibre dust followed pseudo-second-order kinetics with an average constant of 0.002, 0.003 and 0.004 g/mg min for CFD-1, CFD-2 and CFD-3, respectively. Intraparticle diffusion model was studied to determine the rate-limiting step of the adsorption process. Thermodynamic parameters such as Gibb’s free energy (∆ G °), enthalpy (∆ H °) and entropy (∆ S °) changes were determined for the adsorption process. Negative ∆ H ° value signified that the adsorption process was exothermic in nature. Results from this study demonstrated potential utility of CFD adsorbent which could be developed into a suitable method for fluoride removal from aqueous solution.

Vaishali Tomar - One of the best experts on this subject based on the ideXlab platform.

Ria Bhaumik - One of the best experts on this subject based on the ideXlab platform.

  • Adsorption of fluoride from aqueous solution by a new low-cost adsorbent: thermally and chemically activated coconut fibre dust
    Clean Technologies and Environmental Policy, 2015
    Co-Authors: Ria Bhaumik, Naba Kumar Mondal
    Abstract:

    Fluoride is a persistent and non-Biodegradable Pollutant that accumulates in soil, plants, wildlife and human beings. Therefore, knowledge of its removal, using the best technique with optimum efficiency, is needed. In the present study, the potential usage of coconut fibre ( Cocos nucifera ), which is an agricultural waste, in the adsorption of fluoride from aqueous solutions was evaluated with respect to various experimental parameters including pH, adsorbent dose, contact time, agitation speed, initial fluoride concentration and temperature. The objective is to expand upon research of new and existing fluoride removal technologies or promote a new, alternative process. In the present study, the maximum adsorption capacity was recorded as 12.66, 25.64 and 38.46 mg/g for CFD-1, CFD-2 and CFD-3, respectively. From the kinetic study, it was found that fluoride adsorption by coconut fibre dust followed pseudo-second-order kinetics with an average constant of 0.002, 0.003 and 0.004 g/mg min for CFD-1, CFD-2 and CFD-3, respectively. Intraparticle diffusion model was studied to determine the rate-limiting step of the adsorption process. Thermodynamic parameters such as Gibb’s free energy (∆ G °), enthalpy (∆ H °) and entropy (∆ S °) changes were determined for the adsorption process. Negative ∆ H ° value signified that the adsorption process was exothermic in nature. Results from this study demonstrated potential utility of CFD adsorbent which could be developed into a suitable method for fluoride removal from aqueous solution.

Fabio Fava - One of the best experts on this subject based on the ideXlab platform.

  • Development and assessment of an innovative soil-washing process based on the use of cholic acid-derivatives as Pollutant-mobilizing agents.
    Biotechnology and Bioengineering, 2006
    Co-Authors: Sara Berselli, Emilio Benitez, Stefano Fedi, Davide Zannoni, Alessandro Medici, Leonardo Marchetti, Fabio Fava
    Abstract:

    Surfactant-aided soil washing is often proposed for the restoration of aged organic Pollutant-contaminated soils. As many of commercial surfactants have been found to be toxic and recalcitrant, the opportunity to use in this process cheap, non-toxic, and Biodegradable Pollutant-mobilizing agents, such as deoxycholic acid (DA), bovine bile (BB), and the residue resulting from DA extraction from BB (BBR), was studied in this work. A soil historically contaminated by chlorinated anilines and benzenes, thiophenes, and several polycyclic aromatic hydrocarbons was suspended at 15% w/v and washed in water or water amended at 1.0% (w/v) with DA, BB, BBR, or Triton X-100 (TX). The resulting effluents were supplemented with nutrients and subjected to aerobic bioremediation. The biogenic agents enhanced the water Pollutant elution potential by 230/440%. TX enhanced the same parameter by about 540%; however, it mediated a lower depletion of the initial soil ecotoxicity and a more extensive mobilization of soil constituents with respect to the biogenic agents. Furthermore, TX adversely affected the biotreatability of resulting effluents, by adversely affecting the growth of cultivable bacterial biomass and the structure of eubacterial community of the effluent. On the contrary, the biogenic agents, and in particular DA and BB, enhanced the effluents bioremediation, by sustaining the growth and increasing the complexity of the effluent eubacterial communities. Thus, DA and BB are very promising additives for an effective and environmental friendly soil washing treatment of aged (chloro)organics contaminated soils. © 2005 Wiley Periodicals, Inc.

  • Effects of cyclodextrins, humic substances, and rhamnolipids on the washing of a historically contaminated soil and on the aerobic bioremediation of the resulting effluents
    Biotechnology and Bioengineering, 2004
    Co-Authors: Sara Berselli, Gabriella Milone, Pietro Canepa, Diana Di Gioia, Fabio Fava
    Abstract:

    Nontoxic and Biodegradable Pollutant-mobilizing agents, instead of chemical surfactants, were tested in the washing of an actual-site chloroaromatic-contaminated soil. A soil historically contaminated by chlorinated anilines and benzenes, thiophenes and several polycyclic aromatic hydrocarbons was subjected to washing by suspending it (15% w/v) in water or in water with 1.0% (w/v) beta-clodextrin (beta-CD), hydroxypropyl-beta-cyclodextrin (HP-beta-CD), rhamnolipid (RL), dissolved humic substances (HS), or Triton X-100 (TX) in shaken batch reactors for 24 hr. The resulting wastewaters were amended with nutrients and treated aerobically in shaken reactors for 65 days. The biogenic agents markedly enhanced (by 237%, beta-CD; 265%, HP-beta-CD; 400%, RL; 566%, HS) the capability of water of eluting organic Pollutants from the soil. TX enhanced the overall Pollutant removal by about 660%; however, a lower depletion of the initial soil ecotoxicity, along with a more extensive impact on the soil organic matter, was observed. Furthermore, TX adversely affected the bioremediation of the resulting effluent by apparently inducing a premature decrease of specialized bacterial biomass. By contrast, the biogenic agents, and in particular HS and RL, sustained the biodegradation and dechlorination of Pollutants by apparently enhancing the availability of specialized bacteria in the reactors. Thus, the biogenic agents proposed here seem to be promising nontoxic and nonaggressive soil washing agents for the integrated physicochemical (washing) and biological (aerobic posttreatment) restoration of poorly bioremediable (chloro) organics-contaminated soils.