#TITLE_ALTERNATIVE#

• Main Author: FITRIANTO, KARUNIAWAN
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/28402
• Institution: Institut Teknologi Bandung

<p align="justify">Paint demand in the world is continuing to increase by 3.7% per year, projected to reach 54.7 million metric tons in 2020. The increase of the demand affect to the rise of paint materials supply, one of them is filler. One of the materials that can be used as a filler is magnesite. Known to have a good level of dispersion in paint solution, magnesite can improve the quality of paint. To produce magnesite with optimal performance, magnesite particles size needs to be at least <10 ?m (ultrafine particle). Two main methods for the production of the ultrafine particle are precipitation and ultrafine grinding. The ultrafine grinding method can be carried out in two conditions: wet and dry. However, precipitation and wet ultrafine grinding methods have several constraints such as the difficulty of separating solid particles from the liquid phase or the reagglomeration/reaggregation of particles after the drying process. As an alternative to these two processes, dry ultrafine grinding can be used as an option. Therefore, it is necessary to study the effect of operating variables of the ultrafine grinding process on the grinding product properties. In this study, the effect of %ball filling and ball to powder ratio (BPR) variations on the ultrafine grinding products properties are studied. <br /> <br /> <br /> In this study, the source of the magnesite used was from Padamarang Island, Southeast Sulawesi. The grinding process was carried out for 15 minutes using a Shaker Mill. A steel ball with a diameter of 5 mm was used as the grinding ball. The dry grinding process was carried out with variation of 6%, 8%, 10%, and 12% ball filling and also variation of 2:1, 4:1, 6:1, and 8:1 BPR. Grinding products were then analyzed using PSA, XRD, and SEM to investigate the changes of particle size, particle morphology and the factors that influence those variations. <br /> <br /> <br /> The smallest particle size was obtained at 12% ball filling and 4:1 BPR with d50 and d90 values of 2.48 ?m and 9.19 ?m. The results of SEM image in this treatment indicate that most of the particles did not form agglomerate/aggregate particles. Crystal damage obtained in this treatment is lower compared to other treatments. The increase of %ball filling from 6% to 12% causes smaller crystal damage level, agglomeration/aggregation level, and particle size. The largest particle size was obtained in the treatment of 6% ball filling and BPR 8: 1 with d50 and d90 values of 4.07 ?m and 27.54 ?m. The increase of BPR from 2:1 to 8:1 resulted in larger particle sizes. In addition, increasing BPR also caused crystal damage level and agglomeration/aggregation level to be higher.<p align="justify">