Determination of the Optimum Conditions for the Dissolution of Stibnite in HCl Solutions

Abstract

The Taguchi method has been used to determine optimum conditions for the dissolution of stibnite in HCl solutions. Chosen experimental parameters and their ranges were (i) reaction temperature, 25−70 °C; (ii) solid-to-liquid ratio (in weight), 0.1−0.25; (iii) acid concentration (in weight), 23.71−37%; (vi) mean particle size; 0.1061−0.8426 mm; (v) stirring speed, 200−800 rpm; (vi) reaction time, 5−60 min. The optimum conditions were found to be reaction temperature, 70 °C; solid-to-liquid ratio, 0.125; acid concentration, 37%; mean particle size, 0.1061 mm; stirring speed, 700 rpm; reaction time, 60 min. Under these optimum conditions the dissolution of stibnite was approximately 99%. Next, for the experimental conditions of a time value 15 min less than its optimum value, a value of solid-to-liquid ratio twice its optimum value, and the remaining parameters at their optimum values, it was found that a benefit of 0.023 $/g SbCl3 could be gained from the cost of acid and electricity against a loss of 7.5 × 10-4 $/g SbCl3 as a result of the 1.5% decrease in the Sb recovery due to the changes in optimum conditions.

Determination of the Optimum Conditions for the Leaching of Nonsulfide Zinc Ores (High-SiO2) in Ammonium Carbonate Media

“…The two performance characteristics were evaluated using the following equations: where SNS and SNL are performance characteristics, n is the number of repetitions performed for an experimental combination, and y i is the performance value of the i th experiment . The results of variance analysis are given in Tables −9.…”

“…In such cases, the performance value corresponding to the optimum working conditions can be predicated by utilizing the balanced characteristic of OA. Under these conditions, the following additive model may be used: where μ is the overall mean of performance value, X i the fixed effect of the quantity level combination used in the i th experiment, and e i the random error in the i th experiment 7 Results of the Analysis of Variance for the Dissolution Values of Zinc a parametersum of squares, S degree of freedom, f variance, S / f variance ratio, F reaction temperature ( °C) 3.36 4 0.84 0.27 stirring speed (rpm) 5.40 4 1.35 0.44 ammonium carbonate concentration (mol) 2.03 4 0.70 0.23 reaction time (min) 3.64 4 0.91 0.30 acidity, pH 0.83 4 0.21 0.06 error 12.25 4 3.06 1 total 28.28 24 a F Table = 6.39 with 95% confidence. …”

Applying Taguchi methods to health care

“…While such vigorous research for commercially viable short-cuts and improvements in the industrial and the business sectors should not surprise anybody, the potential application of Taguchi methods to a wide and increasing range of medical applications might surprise the reader. Taguchi methods have so far been applied to Polymerase Chain Reaction (PCR) technique in biochemistry (Cobb and Clarkson, 1994), optimization of polymerization reactions, evaluation of component separation in Liquid Chromatography analysis by dynamic operating window, functionality evaluation of spray drying medicines, measurement of drug efficacy, prediction of urinary continence recovery among patients with brain disease, health examination and treatment of missing data, diabetes mellitus disease duration and capillary bed's area (Taguchi et al, 2004), determination of optimum conditions for the dissolution of Stibnite in HCl solutions in analytical chemistry (Copur et al, 1997), improvement of haemodialysis quality (Konduk and Ucisik, 1998), and a study of factors influencing patients' length of stay in emergency care units (Rinderer, 1996). Also, the variability of measured value from an oxygen sensor used…”

Optimization of leaching parameters of aluminum hydroxide extraction from bauxite waste using the taguchi method

“…Abali et al studied the optimization of the leaching of dolomite ore in hydrochloric acid solution. Copur et al determined the optimum conditions for the dissolution of stibnite in hydrochloric acid solution. Copur et al revealed the optimum conditions for the dissolution of roasted zinc sulfate in sulfuric acid solution.…”