DEVELOPMENT OF POTASSIUM CARBONATE PRODUCTION TECHNOLOGY FROM PALM OIL WASTE AS A SUBSTITUTION OF POTASSIUM CHLORIDE FERTILIZER RAW MATERIALS

• Main Author: Annisa Amalia, Ratu
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/45052
• Institution: Institut Teknologi Bandung

DEVELOPMENT OF POTASSIUM CARBONATE PRODUCTION TECHNOLOGY FROM PALM OIL WASTE AS A SUBSTITUTION OF POTASSIUM CHLORIDE FERTILIZER RAW MATERIALS Oil palm is a plantation commodity that is most widely used in vegetable oil production in Indonesia. In the process of growth, oil palm plants need high amounts of nutrients. The nutrients contained in oil palm plants are mostly stored in palm fruit bunches (FFB). As a result, harvesting FFB from oil palm plantations causes most of the nutrients of oil palm plants to be lost. The missing nutrients, especially potassium, need to be replaced through the addition of fertilizer. At present, KCl fertilizer, one of the fertilizers widely used in oil palm plantations, is entirely from imported products. On the other hand, the palm oil industry produces palm oil waste such as OEFB, shells, and palm fibers which have high potassium content. Potassium in the waste has the potential to be utilized in the production of KCl fertilizer. Thus, the success of potassium recovery from palm oil waste can realize a cycle of potassium utilization in the oil industry which is then expected to reduce Indonesia's dependence on imported KCl fertilizer. One method that can be done to recover potassium is by the extraction process of potassium from waste palm oil. The process of extracting potassium from biomass ash has been carried out in previous studies. However, the extraction process that has been carried out is still on a laboratory scale only. In addition, previous studies tend to focus solely on OEFB only so that data on the extraction process of potassium from other palm waste ash is lack. Therefore, this study was conducted to define the mass balance of the pilot scale extraction process for the recovery of potassium from palm waste ash, to support the cycle of potassium utilization in the oil palm industry. The raw materials used in this study are oil palm empty fruit bunches (OEFB), palm kernel shell charcoal, palm fiber charcoal, and boiler industrial ash. The process of recovering potassium from palm oil ash includes a preliminary experiment and the main experiment. The preliminary experiment consists of the steps of determining the extraction equilibrium time, the number of stages, the ash-solvent ratio, and the ashing temperature. Preliminary experiments showed that the optimum conditions of extraction can be achieved by multi-stage extraction of 3 stages each for 3 hours, using the ash: solvent ratio, 1: 2. The higher ashing temperature used causes the potassium content in the ash to decrease. Overall, the optimum ashing temperature for all raw materials is 400 ° C. iv Meanwhile, the main experiments include the stages of ashing, extracting, evaporation, and making KCl. The extraction process is carried out at a temperature of 80 ° C with continuous stirring using a stirring motor. The solvent used is demineralized water. The number of extraction stages, the ash: solvent ratio and the extraction time used was in accordance with the results of the preliminary experiment. The results of the SEM-EDS analysis showed that the potassium content in the samples of OEFB ash, shell ash, fibrous ash, and boiler ash were respectively 21.68; 10.04; 7.56; and 4.27% -mass. The final product in the form of potassium salt obtained from each OEFB ash, shell ash, fibrous ash, and boiler ash is 36.64; 3.96; 2.94; and 1.98% ash mass. Potassium yield obtained is 89.98% from OEFB ash; 18.75% from shell ash; 14.22% from fiber ash; and 20.36% from boiler ash. Salt from OEFB ash is dominated by potassium carbonate while salt from other ash is dominated by other potassium salts namely KCl and K2SO4. Salt with the highest content of potassium carbonate was obtained from extraction using OEFB ash that is equal to 70.28% K2CO3 mass. In this experiment, the production of KCl from potassium carbonate salt from OEFB ash extract was also carried out and gave a product with a dominant KCl content. However, the KCl content of the salt product produced is only 67.11% so that further refining processes need to be carried out to produce KCl salts that comply with commercial KCl specifications.