Langmuir maximum adsorption capacity

Maximum adsorption capacity The maximum amount of an adsorbate, often measured in molal, that a given mass of an adsorbent can adsorb. A Langmuir isotherm may approach the maximum adsorption capacity. 

Figure 4.2 shows the Langmuir isotherms of (a) phenobarbital and (b) mephobar-bital adsorption on activated carbon. The maximum adsorption capacity (K,/K2) of activated carbon for mephobarbital is lower than that for phenobarbital. The affinity constant (1/K2) for mephobarbital is higher than that for phenobarbital. This is expected because higher solubility gives a lower adsorption affinity. Table 4.1 illustrates the Langmuir constants of various drugs on carbon black. 

The slopes and linear coefficients of lines allow to determine the Ng and values corresponding to these runs these values are almost the same as those determined by means of Equation (19) (error percentage, +4%). Eigure 8 also reports the adsorption results obtained in the absence of irradiation, that is, in the dark. A least-squares best fitting procedure allows to determine the values (R > 0.99) of the Langmuir equilibrium constant and the maximum adsorption capacity in the absence of irradiation, that is, fCL = 350 and Ns = 4.57 x 10 mol/g of catalyst. 

Cd Zn" and on ETS-10 using a batch-type technique. Our observations have not only confirmed that ETS-10 does exhibit a remaritable adsorption rate towards heavy metal ions but also demonstrated that the maximum adsorption capacity of Pb on ETS-10 is as high as 1.12 mmol/g according to the prediction of Langmuir model. This is the highest uptake that has been observed on zeolite materials [1]. 

Figure 11.9d) fitted well with Langmuir isotherm model with the calculated maximum adsorption capacity to be 1149.4 mg/g, which is the highest capacity as compared with other polymer-based adsorbents (Figure 11.9e). Besides, the adsorption capacity had no obvious reduction even after seven... 

ABSTRACT Ephedra waste was modified by epichlorohydrin and diethylenetriamine to obtain aminated ephedra waste biosorbent. The factors affecting the adsorption efficiency, such as pH and contact time were investigated. The results showed that the optimum absorption conditions of aminated ephedra waste pH was 4.7 contact time was 3 h equilibrium was well described by Langmuir isotherms and kinetics was found to fit pseudo-second order type. According to the Langmuir equation, the maximum adsorption capacities of modified adsorbent for Cu + are 93.11 mg/g, which are higher than untreated adsorbent (17.61 mg/g). The aminated ephedra waste biosorbent had excellent absorbability toward heavy metal ions Cu f... 

The batch adsorption is assumed to be visualized by the application of adsorption isotherm models. The different isotherms give an indication of how the contaminants from MDEA solution interact with the PAAM functional groups and distribute themselves over hydrogel surface. The equilibrium adsorption isotherms of total metal ions as well as organic acid anions were determined at 23°C. The equilibrium MDEA concentration (Ce) for varions uptake capacities of heavy metal ions and HSS anions (qe) were fitted to four standard isotherm models and it was observed that Langmuir isotherm best fitted among all. The maximum adsorption capacity (qmax) valnes obtained from the isotherm model using PAAM... 

Considering the fraction of sites occupied 0a as the ratio of the concentration of the adsorbate on the solid phase (mg g-i) and the concentration of adsorbate in solid phase in saturation (mg g-i) also known as maximum adsorption capacity, we have Equations 5 and 6, the latter being known as the Langmuir s Equation. 

The Langmuir s equation can be linearized, yielding experimental values of the equilibrium constant Ka and maximum adsorption capacity according to Equation 8. 

C h is the maximum adsorption capacity while b is the ratio of rate coefficients of adsorption and desorption, or the Langmuir affinity constant, defined as ... 

Another parameter, and perhaps the most important one because it offers information about the maximum adsorption capacities of the studied materials, is the influence of the initial concentration of the studied metal ions. In all the studies the experimental data regarding the variation of the initial concentration of the metal ions are fitted with the help of isotherm models. The most widely used isotherm and which is perfectly fitted in all cases is the Langmuir isotherm. In Table 11.1 are summarized the maximum adsorption capacities obtained from the Langmuir isotherm in cases of various removal... 

Beside kinetic and thermodynamic studies, equilibrium studies were done in order to determine the influence of the initial concentration of the metals ions upon the efficiency of the adsorption process and in order to determine the maximum adsorption capacities of the phosphorylated chitin and chitosan materials in the removal process of various metal ions from aqueous solutions. The experimental equilibrium data were fitted to the Langmuir and Freundlich isotherms. In all the cases the experimental results showed a better fit to the Langmuir than to the Freundlich equation. The maximum adsorption capacities obtained from the Langmuir isotherm plot in the... 

The pure component adsorption equilibrium of ethane and propane are measured on Norit AC at three temperatures (30, 60 and 90 °C). All experimental data of two species at three temperatures are employed simultaneously to fit the isotherm equation to extract the isothermal parameters. Since an extended Langmuir equation is used to describe the local multicomponent isotherm, the maximum adsorbed capacity is forced to be the same for ethane and propane in order to satisfy the thermodynamic consistency. The saturation capacity was assumed to be temperature dependent while the other parameters, bo and u], are temperature independent but species dependent. The derived isotherm parameters for ethane and propane are tabulated in Table 1. The experimental data (symbols) and the model fittings (solid lines)... 

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