Enhancement of Caloric Value of Scirpus grossus After Phytotoxicity Test of Lead (Pb)

Abstract

Phytoremediation is one of the methods to clean up the environment from heavy metal contamination. This method has some advantages such as aesthetically pleasing, less disruptive than current techniques, effective in contaminant reduction, low cost, applicable for wide range of contaminants and an environmental friendly method. However, the main concern is the amount of plant biomass produced, because this can create another problem of contamination that has to be solved. There are many kinds of plants that could act as a hyperaccumulator and play an important role in phytoremediation process. Several studies have been conducted to use plant biomass as phytoremediation by product as bioenergy alternative in order to get advantage from the limitation factor of this method. This study aims to get information about the enhancement of caloric value of Scirpus Grossus after it is being used in phytotoxicity test of Lead (Pb). The phytotoxicity test was conducted in a single exposure system, by diluting analytical grade of iron salt Pb(NO3)2 in deionized water. The concentration of Pb was varied in 0 mg/L (control), 100 mg/L, 200 mg/L, 400 mg/L, and 800 mg/L, and all treatment were done in triplicate. The caloric value was measured by using Bomb Calorimeter which showed the increment as the Pb concentration increased up to 400 mg/L Pb exposure, and started decreasing with the increase of concentration of Pb exposure (600 and 800 mg/L). The caloric value for the lead exposure of 100, 400, 600 and 800 mg/L was respective 10,200, 14,400, 8,000 and 9,600 J/g. The decrease in 600 and 800 mg/L were expected since in both exposures, all plants were withered. However, all values were still higher than that of plants in the control pail (without contaminant) of 6,300 J/g. This result shows that the use of plant as contaminant uptake in phytoremediation can enhance the caloric value of the plant. And this will over rule the limitation of large production of plant biomass whereby it can be used as bioenergy alternative according to the enhancement of its caloric value.