keywords: Biosorbent; calcareous and cockle shell; heavy metal ions; sorption equilibrium
This study examined the suitability of cockle shell (CS) powder in the removal of Pb2+ and Zn2+ metal ions. The high rate of discharge of heavy metals often regarded as cumulative poisons into the environment through industrial processes and metallic waste prompted this research. The properties of this calcareous adsorbent were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) channel structure measurements and Fourier Transform Infrared spectrometry (FTIR). The influences of concentration, pH, contact time, adsorbent dose and temperature on the sorption capacity of these adsorbents were investigated. The results revealed cockle shell as a good adsorben t for both Pb2+ and Zn2+ ions in aqueous media with both ions exhibiting competitive adsorption behaviour. At a solution concentration of 100 mg/L, Pb2+ and Zn2+ uptake by cockle shell were 24.66 and 21.70 mg/g, respectively. The adsorption of these metal ions was modelled using Langmuir, Freundlich, Temkin and Dubinin-Raduskevich isotherms. Freundlich and Dubinin-Radushkevichisotherms adequately described the sorption Zn2+ and Pb2+, respectively by the cockle shell. The thermodynamics and kinetics studies also revealed that the adsorption process was endothermic in nature and followed pseudo second order.
Abdus-salam N&Adekola FA 2005.The influence of pH and adsorbent concentration on adsorption of lead and zinc on a natural goethite.African Journal of Science and Technology (AJST) Science and EngineeringSeries, 6(2): 55 – 66. Aiyesanmi AF, Okoronkwo AE &Akinmolayan, BM 2013.Equilibrium Sorption of Lead and Nickel from Solutions by Flame of the Forest (Delonixregia) Pods: Kinetics and Isothermic Study. Journal of Environmental Protection, 4: 261-269. Asi H &Gautam A 2013.Cadmium biosorption potential of shell dust of the fresh water invasive snail (Physaacuta).Journal of Environmental Chemical Engineering,1: 574–580. Awang-Hazmi AJ, Zuki ABZ, Nordin MM,Jalila A &Norimah Y 2007. Mineral composition of the cockle (Anadaragranosa) shells of west coast of peninsular Malaysia and its potential as biomaterial for use in bone repair. Journal of Animal and Veterinary Advances,6(5): 591-594. Badmus MAO, Audu TOK &Anyata BU 2007.Removal of Lead ion from Industrial Wastewaters by Activated Carbon Prepared from Periwinkle Shells (Typanotonusfuscatus).Turkish Journal of Engineering and Environmental Science, 31: 251 – 263. Bharathi KS & Ramesh SP 2012. Equilibrium, thermodynamic and kinetic studies on adsorption of a basic dye by Citrulluslanatusrind. Iranica J. Energy and Environ., 3(1): 23-34. Brown TL, LeMay HE &Bursten BE 1991. Chemistry: The Central Science, 5th ed., New Jersey: Prentice Hall, 495. Dahiya S, Tripathi RM &Hedge AG 2008.Biosorption of lead and copper from aqueous solutions by pre-treated crab and arca shell biomass.Bioresource Tech., 99: 179–187. Edu I, Ubong E, Eduok U& Joseph E 2012.Heavy metals sorption potential of calcareous shells of animal origin.Int. J. Chemical, Environmental and Pharmaceutical Res.,3(3): 184-194. Faust DS & Aly MO 1983.Chemistry of Wastewater Treatment.Butterworthworts. Boston. Freundlich H 1907. Ueber die Adsorption in Loesungen Z. Physik Chemistry,57: 385 – 470. Genson M, CharlesOO & Gerald KM 2012.Kinetic and equilibrium study for the sorption of pb(ii) ions from aqueous phase by water hyacinth (Eichhorniacrassipes). Bull. Chem. Soc. Ethiopia, 26(2): 181-193. Gerente C, Lee, VKC, Le Cloirec P & McKay G 2007. Application of chitosan for the removal of metals from wastewaters by adsorption – mechanisms and models review.Critical Reviews in Envtal. Sci.& Tech., 37: 41–127. Gifford S, Dunstan RH, O’Connor W, Koller CE & MacFarlane GR 2006. Aquatic Zoo-remediation: Deploying animals to remediate contaminated aquatic environment. Trends in Biotech, 25: 60–65. Hutson ND & Yang RT 1997.Theoretical basis for the Dubinin–Radushkevitch (D–R) adsorption isotherm equation. Adsorption, 3: 189–195. Kathrine C & Hans C 2007.Sorption of zinc and lead on coir.Bioresource Tech., 98: 89–97. Langmuir I 1918.The adsorption of gases on plane surfaces of glass, mica and platinum.J. American Chem. Soc., 40(9):1361 – 1403. Liu Y, Sun C, Xu J & Li Y 2009. The use of raw and acid pretreated Bivalve mollusc to remove metals from aqueous solutions. Journal of Hazardous Material, 168: 156–162. Low KS, Lee CK & Lee KP 1993.Sorption of copper by dye-treated oil palm fibre.Bioresource Tech., 44: 109-112. Monika J, Garg V&Kadirvelu K 2009.Chromium (VI) Removal from aqueous solution, using sunflower stem waste.Journal of Hazardous Materials, 162: 365 – 372. Mustakimah M, Suzana Y &Saikat M 2012.Decomposition study of calcium carbonate in cockle shell.J. Engineering, Sci. and Tech., 7(1): 1 – 10. Ozcan A, Ozcan AS &Gok O 2007.Adsorption kinetics and isotherms of anionic dye of reactive blue 19 from aqueous solutions onto DTMA-sepiolite. In: A.A. Lewinsky (ed.), hazardous materials and wastewater–treatment, removal and analysis.Nova Science Publishers, New York. Pena-Rodriguez S, Fernandez-Calvino D, Novoa-Munoz JC, Nunez-Delgado A, Fernandez-Sanjurjo MJ & Alvarez-Rodriguez A 2010. Kinetics of Hg(II) adsorption and desorption in calcined mussel shells. J. Hazardous Material, 180: 622–627. Qadeer R &Hanif J 1994.Kinetics of zirconium ions adsorption on activated charcoal from aqueous solution. American J. of Biochem. and Biotech. 3(2): 34-43. RRUFF 2014. Calcite [Online]. Available from: http://rruff.info/Calcite/R040078. Accessed: 13-06-2014. Santhi T, Manonmani S &Smitha T 2010.Kinetics and Isotherm Studies on Cationic Dyes Adsorption onto AnnonaSqumosaseed activated carbon.Int. J. of Engineering Sci. and Tech., 2(3): 287-295. Stevens AO &Nnabuk OE 2009.Studies on the use of oyster, snail and periwinkle shells as adsorbents for the removal of Pb2+from aqueous solution.E-Journal of Chemistry,6(1):213-222. Unuabonah EI, Adebowale KO &Olu-Owolabi BI 2007.Kinetic and thermodynamic studies of the adsorption of lead (II) ions onto phosphate-modified kaolinite clay.J. Hazardous Material, 144: 386–395. Wikipedia 2013.Heavy Metals.[Online]. Available from:http://en.wikipedia.org/wiki/Heavy_metal_chemistry. Accessed: 16-12-2013. Wu FC, Tseng RL &Juang RS 2009.Initial behavior of intraparticle diffusion model used in the description of adsorption kinetics.Chem. Engineering J., 153: 1–8. Xin-jiang H, Yun-guo L, Guang-ming Z, Hui W, Xi H, An-wei C, Ya-qin W, Yi-ming G, Ting-ting L, Lu Z, Shao-heng L & Xiao-xia Z 2014.Effect of aniline on cadmium adsorption by sulfanilic acid-grafted magnetic graphene oxide sheets.J. Colloid and Interface Sci.,426: 213–220. Yeddou N &Bensmaili A 2007.Equilibrium and kinetic modeling of iron adsorption by eggshells in a batch system: Effect of temperature. Desalination, 206(1–3): 127–134.