This investigation aimed to create Carboxymethyl Cellulose (CMC) from the nata de coco cellulose. The nata de coco was produced by fermentation method of coconut water used acetobacter xylinum. Bacterial cellulose (BC) was isolated by furification nata de coco with 1% NaOH and 1% acetic acid solutions respectively. In the process of making CMC, dried BC was immersed in isopropanol medium, then alkalised with 10%, 15% and 20% NaOH solutions respectively for 1 hour at a temperature of 55 oC. Then BC reacted with 18 grams of chloroacetic acid. FTIR analysis results show that CMC was successfully synthesized from BC. The increase in NaOH concentrations in the CMC preparation caused an increase in the degree of substitution (DS). DS is one of the main parameters of the success of the CMC synthesis process from the initial raw material for cellulose. At a concentration of 20% NaOH, the resulting CMC synthesized with DS 0.743 was better than 10% NaOH with DS 0.371.

An experiment has been conducted to determine corrosion rate of medium carbon stell with sulfuric acid solution, Aquades 90,2% + H2SO4 9,8% and hydrochloric acid solution, Aquades 96,8% + HCl 3,2%. By using weight loss method, if medium carbon steel dipped into sulfuric acid solution then the corrosion rate is faster than it dipped into hydrochloric solution. If medium carbon steel dipped in a long time than the corrosion rate slowing down.