Batch adsorption

Batch adsorption is often used to adsorb solutes from liquid solutions when the quantities treated are small in amount, such as in the pharmaceutical industry or other industries. As in many other processes, an equilibrium relation such as the Freundlich or Langmuir isotherms and a material balance are needed. The initial feed concentration is Cf and the final equilibrium concentration is c. Also, the initial concentration of the solute adsorbed on the solid is qf and the final equilibrium value is q. The material balance on the adsorbate is 

When the variable q in Eq. (12.2-1) is plotted versus c, the result is a straight line. If the equilibrium isotherm is also plotted on the same graph, the intersection of both lines gives the final equilibrium values of q and c. 

EXAMPLE 12.2-1. Batch Adsorption on Activated Carbon A wastewater solution having a volume of 1.0 m contains 0.21 kg phenol/m of solution (0.21 g/L). A total of 1.40 kg of fresh granular activated carbon is added to the solution, which is then mixed thoroughly to reach equilibrium. Using the isotherm from-Example 12.1-1, what are the final equilibrium values, and what percent of phenol is extracted  

12 Liquid-Liquid and Fluid-Solid Separation Processes 

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FIG. 16-14 Constant separation factor batch adsorption curves for external mass-transfer control with an infinite fluid volume and n j = 0. 

FIG. 16-16 Batch adsorption curves for solid diffusion control. The curve for A = 0 corresponds to an infinite fluid volume (adapted from Ruthven, gen. refs., with permission). 

Parallel Pore and Solid Diffusion Control With a linear isotherm, assuming equilibrium between the pore fluid and the solid adsorbent, batch adsorption can be represented in terms of an equivalent solid diffusivity = ( pD i + ppD, )/( p + pp Q). Thus, Eqs. (16-96) and (16-99) can be used for this case with D, replaced by D. ... 

Lee [AJChE J., 24, 531 (1978)] mes the solution for batch adsorption with bidispersed particles for the case of a finite fluid volume. 

Dried shrimp was ground, defatted with benzene, and then extracted with cold water. The luciferase extracted was purified first by a batch adsorption onto DEAE cellulose (elution with 0.4 M NaCl), followed by gel filtration on a column of Sephadex G-150, anion-exchange chromatography on a column of DEAE-cellulose (gradient elution 0.05-0.5 M NaCl), and gel filtration on a column of Ultrogel AcA 34. The specific activity of the purified luciferase was 1.7 x 1015 photons s 1 mg-1, and the yield in terms of luciferase activity was about 28%. 

Such an idea was patented in 1981 (14). Besides research by Scamehom and Schechter (15) provided an experimental illustration of this by batch adsorption tests of kaolinite with some purified anionic/nonionic products. Our objective was to enlarge and test this technique under the dynamic flow conditions of industrial surfactant injection in an adsorbent porous medium. 

Batch adsorption experiments by Yee and Fein (2002) using aqueous Cd, B. subtilis, and quartz as a function of pH showed that the thermodynamic stability constants, determined from binary systems, could successfully describe the distribution of Cd between the aqueous phase and the bacterial and mineral surfaces. The constants could also be used to estimate the distribution of mass in systems, and construct a surface complexation model. 

Cyclic aromatic disulfides, polymerization reactions of, 23 706 Cyclic (arylene) disulfides, 23 712 Cyclic batch adsorption processes, 1-613 Cyclic bis(arylene tetrasulfide)s, 23 712 Cyclic carbon, polymer materials with, 15 177... 

Batch adsorption experiments were performed at a constant temperature (20 2°C) on a magnetic stirrer nsing 100 mL erlemnayer flasks. In bath experiments, adsorption time, particle size of adsorbent, adsorbent amonnt, pH profile, and adsorbent/ liquid ratio were performed to determine binding properties of adsorbent for the Cu + ions. The concentration of the metal ions in solntions before and after adsorption was measnred with an AAS. 

Batch adsorption tests were done at five different particle sizes 300, 425, 600, 710 and 850 pm. 0.1 g of the sumac leaves was weighed and 8 ttiL of ion solution was added. The volume was completed 50 ttiL. After stirring 2 h, the reaction mixtures were filtered through a filter paper to remove particulates and the filtrate was analyzed with an AAS. 

Batch adsorption experiments were carried out at the desired temperature (20°C, 30°C and 40°C) and each used a range of pH from 6 to 10. The concentration of Cu + was kept 10 pg mL particle sizes < 300 pm and amount of adsorbent 0.2 g, stirring time 4 h. 

To investigate of the effect of particle size on the adsorption of Cu " ions, batch adsorption tests were done at five particle size. The percentage of adsorption of Cn + indicates that increasing particle size was decreased the percentage adsorption (Table 28.1). Therefore <300 pm was found to be appropriate for maximum adsorption and was nsed in all subsequent measurement. 

Batch adsorption experiments. All experiments were performed with Hg-203 (TRC Amersham),to determine the distribution coefficient K defined as ... 

For a typical batch adsorption experiment 300 mg of the dry sorbent and 5.0 ml of liquid phase formulated to the desired (constant) composition and pH were sealed in acid prewashed 10 ml screw cap vials with teflon closures and shaken for 18 hours. 

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