Abstract:
In this study, the adsorption and desorption kinetics of lanthanum (La) on micro algal cells was investigated.
The internal transcribed spacer (ITS) and 18S ribosomal RNA gene (rRNA) were used for molecular
identification of the species. The algal species were found to have 95–98% identities to Desmodesmus multivariabilis,
Scenedesmus acuminutus, Chloroidium saccharophilum and Stichococcus bacillaris. The species
were cultured and tested independently. D. multivariabilis was found to be the most efficient at adsorbing
lanthanum with a maximum sorption capacity (qmax) of 100 mg/g and a high affinity (b) of 4.55 L/g.
Desorption of La was also highest in D. multivariabilis with recovery up to 99.63% at initial concentration
as high as 100 mg/L. Desorption data fitted best to the modified pseudo second-order with a better correlation
coefficient (R2) of 60.98 than first order model. The results showed feasibility of lanthanum
recovery using algal sorbents, a cost effective method.
