EKERE, N. R.; AGWOGIE, A. B.; IHEDIOHA, J. N.. Removal of of Pb(II), Cd(II), Cu(II) and Ni(II) Ions from Aqueous Solution Using Pentaclethra Macrophylla Stem Activated Carbon. Pakistan Journal of Analytical & Environmental Chemistry, [S.l.], v. 19, n. 2, p. 195-204, dec. 2018. ISSN 2221-5255. Available at: <http://pjaec.pk/index.php/pjaec/article/view/475>. Date accessed: 18 aug. 2019. doi: http://dx.doi.org/10.21743/pjaec/2018.12.21.