Water used in industries creates a wastewater that has a potential hazard for our
environment because of introducing various contaminants such as heavy metals into soil and water
resources. In this study, removal of cadmium, lead and nickel from industrial wastewaters has been
investigated by using teawaste as a natural adsorbent. The research is a bench scale experimental type
and analyses have performed by using different amounts of adsorbent in solutions with 5 different
concentrations of each metal and also in a mixed combination. Besides, the effect of various amounts
of teawaste used in adsorption efficiency experiments has been investigated. Results indicate that the
removal efficiency is highest for lead and is minimum for cadmium. About 94 and 100% lead removal
were achieved by using 0.5 and 1.5g adsorbent for solutions having concentrations of 5 and 10 mg/L
Pb. Whereas, 1.5g teawaste can treat nickel solution of 5 mg/L concentration with an efficiency of not
more that 85.7%. For cadmium, the efficiency was only 77.2% in the same conditions. On the other
hand, for mixtures of metals and by applying 0.5 g teawaste, we considered a 3.5% decrease in lead
removal efficiency and a 13.2% decrease in nickel adsorption for a mixed solution of 5 mg/L.