BIOFLOCULATION OF CLAY MINERAL USING BIOSURFACTANT BACTERIA-PRODUCING AS A FLOCULATION AGENT

• Main Author: Lidya Fathira, Riri
• Format: Theses
• Language: Indonesia
• Subjects: Karya Umum
• Online Access: https://digilib.itb.ac.id/gdl/view/44027
• Institution: Institut Teknologi Bandung

Flocculation is a destabilized particle forming agglomeration (floc) with the addition of flocculants so that it can be separated by filtration. Flocculation are used in the process of thickening, sedimentation, tailings treatment, wastewater treatment and water treatment. The flocculant used is usually a chemical reagent. The use of chemicals in the flocculation process is able to eliminate or reduce pollutants, but is less environmentally friendly and requires expensive costs. Therefore, an environmentally friendly and inexpensive treatment method is needed as an alternative to chemical reagents by utilizing microorganisms as bioreagents. In this study, the selection of bacteria and growing media suitable for the biofloculation process was carried out. The emulsifying index (% EI) test was also conducted to show that the effect of biosurfactant as an emulgator can reduce surface tension which causes faster deposition of clay mineral. There were nine bacteria used in biofloculation testing. The mineral content of clay minerals was analyzed using X-Ray Diffaction (XRD) and X-ray Fluorescence (XRF). In addition, FTIR (Fourier Transform Infra Red) and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) analyzes were conducted to determine the interaction of clay minerals and bacteria. The results of this biofloculation test showed LA and BS 5 bacteria with a pH of 2, contact time of 3 minutes, and a bioreagen dose of 10% were able to precipitate clay mineral and the value of turbidity levels of supernatant <200 mg / L. The flocculating rate LA and BS 5 bacteria were 0.96 and 0.85 cm / min, respectively. FTIR analysis results showed the formation of carbohydrate and carboxyl groups proves that LA and BS 5 bacteria are biosurfactant-producing bacteria.