Experimental design modelling for the extraction of vanadium(IV) extraction V(IV)-SO4 2- (H+, Na+)-Cyanex 301-kerosene system

The vanadium(IV) extraction from acidic sulphate medium by Cyanex 301 (bis-(2,4,4-trimethylpentyl) dithiophosphinic acid) dissolved in kerosene is explored from the modelling point of view. The time of equilibration is only 10 min and above pH(eq) = 2, high extraction (>90%) occurs.On keeping organic to aqueous phase ratio of 1, factors affecting the extent of extraction (log D and log CD) are pH(eq), [V(IV)],[SO4 2-], [Cyanex 301]and temperature (T). The high (+) and low (-) levels are considered for the factors. The 25 factorial design is used to find the regression equation for the V(IV) extraction by Cyanex 301. On symbolizing pH(eq), log [V(IV)], , log [SO4 2-], log [Cyanex 301], and 1/T (K-1); where concentration terms are in mol/L, as P , M, S,E, and (1/T), respectively,the regression equation obtained is: log CD = 1.95 - 0.23 M + 1.83 P + 2.07 E + 0.84 S - (888.9/T) - 0.26 PS.The current system shows only the interaction effect among pH(eq) and [SO4 2-]. The equation can well describe the system,and it can be used to optimize factors for satisfactory extraction. Bangladesh J. Sci. Ind. Res.56(2), 95-104, 2021

ANALISIS PROFIL PENGARUH BAHAN ORGANIK TERHADAP KONSENTRASI BESI FERRO DAN SERAPANNYA DI LAHAN RAWA PASANG SURUT

<p>This study aimed to determine the similarity of the characteristics of each type of organic matter in suppressing the solubility of iron in soil and absorption in plants. This research was conducted in two stages. The first stage was conducted in the greenhouse to study the effect of organic matter to iron solubility in acidic sulphate soil. The research used a factorial design with 1 control and 3 replications. The first factor was type of organic matter used, B1 = rice straw; B2 = weeds; B3 = Combination of 50% rice straw and 50% weeds. The second factor was the incubation period of organic matter I1 = 2 weeks, I2 = 4 weeks, I3 = 8 weeks, and I4 = 12 weeks. The second stage was analyzing the profiles of the type of organic matter in order to evaluate the similarity of the characteristics of each type of organic matter. Based on the profile alignment, it was found that the three types of organic matter were not aligned. The types of organic matter had different roles in suppressing the solubility of iron in soil and its absorption in plants. There is a need to do a comparative analysis with Tukey method to the three types of organic matter.</p>