BIOREMEDIATION OF MERCURY CONTAMINATED SOIL USING CONSORTIUM OF BACTERIA UNDER ANAEROBIC CONDITION

• Main Author: Panha, YOS
• Format: Theses
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/44118
• Institution: Institut Teknologi Bandung

: Mercury (Hg) is found as one of the most toxic heavy metal polluted into water and soil. This research aimed to study the transformation of Hg by consortium of bacteria throughout bioremediation technology. Indigenous bacteria isolated from mercury contaminated site was enriched and inoculated onto nutrient broth (NB) as the acquisition of bacteria growth. The consortium of bacteria were found to be the strain of Bacillus cereus, Bacillus Sp and Brevundimonas diminuta which had enough capability to transform the toxicity form of mercury to the less toxic form. Growth of bacteria were tested in several concentrations of Hg whereas in pure culture, 50ppm Hg, and 100ppm Hg. Result presented the potential of growth in the used medium and bacteria grew faster orderly in no/less to high Hg concentration. Bacteria started its log phase after 4 and 20 hours inoculation in pure culture and 50ppm Hg while the growth prolonged its lag phase to 52 hours in 100ppm Hg. Microcosm study of mercury reduction in liquid medium showed the rate of removal was in the range of 0.602mg/l/day to 0.672mg/l/day. Experimental treatments were done using synthetic soil under anaerobic condition with 60 days of observation. In lab scale of soil treatment, the highest removal of mercury under influence of temperature was 73.32% with 45oC while the highest removal under influence of pH was 68.82% with the pH of 4-5 and the highest removal under nutrient amendment was with CNP of 100:10:1 with efficiency of 75.02%. There was 0.02% in atom of Hg(0) was found to be adsorbed onto the activated carbon analyzed by SEM-EDS. The oxidation reduction potential (ORP) was measured in the range of -100mv to 100mv considering as reduced soil condition or anaerobic soil. To sum up, the isolated bacteria represented to potential in detoxifying Hg while Hg removal was better with anaerobic condition. High concentration of Hg did not inhibit growth of isolated bacteria but it just prolonged the adaptation stage of bacteria.