STUDI POTENSI ENDOSPORA BACILLUS SP. F7 DALAM FORMULASI SOL-GEL COATING SEBAGAI AGEN PENGHAMBAT BIOKOROSI BAJA ST-37 PADA MEDIA AIR FORMASI (BRINE WATER)

• Main Author: Widia Trisakti, Sheila
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/54185
• Institution: Institut Teknologi Bandung

Biocorrosion is the process of deterioration of metal materials by the activity of various microbes that are inherent in the form of biofilms in petroleum industrial pipes. It is known that the internal corrosion process in pipelines is caused by reservoir formation water (brine water) being transported along with the oil. Brine water can cause corrosion due to the presence of corrosive substances such as chloride salts, organic acids and CO2 gas. Prevention of pipe damage due to corrosion can be done by providing a barrier layer (coating). Silica-based sol-gel coatings are known to act as corrosion inhibiting agents. Bacterial cells can be added to the sol-gel coating for long-term application. One of the bacteria that has the potential as a corrosion inhibiting agent is Bacillus sp. which can form spores. This study aims to optimize the use of Bacillus sp F7 bacterial endospore production media and the sol-gel coating technique used and determine the effect of adding various concentrations of Bacillus sp. Spores. in sol-gel coating against biofilm formation and corrosion resistance level of ST-37 steel. To optimize the sol-gel coating on ST-37 steel, a metal roughness test was carried out with various grades of sandpaper and optimization of coating techniques. Optimization of spore production was carried out on two types of media, namely NB + 0.1% CCY salt and medium 2xSG. The spore viability test in sol-gel was carried out using the ALT method which then obtained variations in spore concentrations of 104, 106, and 108. The analysis of biofilm formation was carried out using the ALT method, while the resistance level and corrosion rate were carried out using the weight loss method. Based on the optimization, the roughness results were obtained with sandpaper grade 600 and the dip coating technique had the best sol-gel coating quality which was confirmed by visualization of metal immersion in 5% NaCl solution. The spore viability of Bacillus sp. The optimum F7 in the silica sol-gel system of 33% was obtained from the production of media with NB + 0.1% CCY salt. Based on the results of the dynamic analysis of the biofilm after 3 days of incubation, a reversible initial attachment stage was observed because there was still an increase in the decrease in the number of cells in the biofilm. Meanwhile, for the analysis of the corrosion rate, the trend of decreasing corrosion rate was observed in the silica sol-gel coating treatment. From the results of the study, it can be concluded that the production medium of endospore NB + 0.1% CCY salt can produce better viability. In addition, the addition of variations in the concentration of endospores Bacillus sp. F7 in ST-37 steel sol-gel coating can reduce the corrosion rate but its effect on biofilm formation has not been determined due to its short incubation time.