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The biosorption properties ofCocos nuciferashell andMoringa oleiferaseeds for Pb(II) were investigated under batch mode. The optimum pH values obtained for the removal of Pb(II) by theCocos nuciferashell and theMoringa oleiferaseeds were 5 and 2, respectively. The equilibrium biosorption capacities obtained were 2.3 mg g−1 (Moringa oleiferaseeds) and 1.6 mg g−1 (Cocos nuciferashell). The Freundlich isotherm model described the removal of Pb(II) by the biosorbents better than the Langmuir model. TheCocos nuciferashell sorbed 83.34% of the Pb(II) ions in 30 min, while 94.03% was sorbed by theMoringa oleiferaseeds in the same time. The results indicated a fast kinetics for Pb(II) sorption by the biosorbents investigated. The biosorption of Pb(II) ontoCocos nuciferashell andMoringa oleiferaseeds followed the pseudo second-order kinetics withR2values of 0.9997 and 0.9999, respectively. The second-order rate constant (k2) obtained were 0.205 g mg−1min−1(Cocos nuciferashell) and 0.067 g mg−1min−1(Moringa oleiferaseeds). The results indicate that intraparticle diffusion controls the rate of biosorption in this study. This study shows thatCocos nuciferashell andMoringa oleiferaseeds can be important low-cost biosorbents for Pb(II) ions. [ABSTRACT FROM AUTHOR]