ON THE USE OF ANOVA AND TAGUCHI METHODS TO STUDY THE SIGNIFICANCE OF THE EFFECT OF VARIABLES AND ITS OPTIMIZATION FOR BANGKA ILMENITE CONCENTRATE LEACHING EXPERIMENT IN HYDROCHLORIC ACID SOLUTION

• Main Author: El Haq, Arzaliya
• Format: Final Project
• Language: Indonesia
• Subjects: Metalurgi
• Online Access: https://digilib.itb.ac.id/gdl/view/49175
• Institution: Institut Teknologi Bandung

Ilmenite (FeTiO3) is a main titanium mineral which is a primary raw material for production of pure titanium metal and compounds. The presence of titanium in the earth crust is approximately 90% in the form of ilmenite. Ilmenite contains TiO2 ranging from 30% to 65%. One of the titanium extraction methods through hydrometallurgical route is by leaching in hydrochloric acid. Ilmenite leaching process in hydrochloric acid has been studied by numerous reseachers. However, the previous works mostly did not evaluate the significance of the effect of the experimental variables on the extraction percentage of titanium. In this study, the significance of the effect of leaching variables on the extraction percentage of titanium from ilmenite concentrate from Bangka Island in hydrochloric acid was investigated by ANOVA and experimental design as well as optimization of variable was done by Taguchi method. The experimental work began with preparation of ilmenite concentrate to obtain the concentrate sample with particle size fraction of -200+325#. Afterward, the sample was analyzed by X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) to identify the predominant mineral and chemical composition of the ilmenite concentrate. Before the leaching process was carried out, the experiment was designed by using an orthogonal array L9 (34). The leaching experiment was carried out at constant variable of particle size fraction of -200+325# and agitation speed of 500 rpm. Meanwhile, the variations used in this leaching experiment are leaching time (4 hour, 6 hour and 8 hour), leaching temperature (80°C, 90°C and 100°C), HCl concentration (4 M, 6 M and 8 M) and solid percentage (10%, 15% and 20%). After obtaining the data of extraction percentage of Ti and Fe from various experimental conditions, the data were analyzed by ANOVA and Taguchi methods to obtain the significance effect of the variables on the extraction percentage of titanium and to optimize the experimental variables. The experimental results showed that the highest extraction percentages of Ti and Fe of 95,38% and 94,10%, respectively obtained at HCl concentration of 8M, leaching temperature 90°C, solid percentage 10% and leaching time 6 hours. The variable optimization by Taguchi method indicated that the optimum conditions for obtaining the highest extraction percentage of Ti is at HCl concentration of 8M, leaching temperature 100°C, solid percentage 15% and leaching time 8 hours. Under specified variable, the results of data processing by ANOVA revealed that the most influencing variables that affects the extraction percentage of titanium is HCl concentration with contribution level of 91.38%, followed by leaching temperature with contribution of 4,04%, solid percentage with contribution of 2,82% and leaching time with contribution of 1,56%.