Screening of some algal species for adsorption of iron, copper and mercury from untreated textile effluent in Kano, Nigeria

Abstract

The research was carried out to screen endogenous species of algae for the adsorption of heavy metals from untreated effluents of Africa Textile Manufacturer (ATM) in Kano between July 2014- June, 2015. Primary field investigation and laboratory analysis were the main sources of data in the study. The study areas were divided into three strata within which samples were collected using stratified sampling techniques from a depth of 0-30cm. The study assessed the adsorption capacity of heavy metals namely: Iron (Fe), Copper (Cu) and Mercury (Hg) by some algal species using Atomic Absorbance Spectrophotometer (AAS). Indigenous algal species identified and isolated were Anabaena planctonica, Microcystis aeruginosa and Spirulina major using microscopy and standard phycological chart as described by Komerak and Anagnostidis, (1989). Bioremediation Bioassay was conducted to assess the adsorption capacity of the isolated organisms. The results showed that, tested organisms reduced the concentration level of heavy metals in the effluents to the standard limit proposed by FEPA (1997), WHO (1999) and (ICLARM, 1997). Spirulina major was found to sequester more Cu (22.80%) followed by Microcystis aeruginosa (21.34%). Higher concentration of Fe (5.77%) and Hg (5.15%) were removed by Microcystis aeruginosa. These findings indicated that all the tested organisms possessed great potential in removing heavy metals from untreated textile effluents. These findings also showed that adsorption of heavy metals by the tested organisms increased with time from 3-9 weeks of inoculation and adsorption was significantly higher at 9 weeks after inoculation.

Keywords: Algal Species, ATM, Effluent and Heavy metals