Kinetic Process of Purple Cabbage Pigment on Macro Porous Absorbent Resin

2011 ◽  
Vol 236-238 ◽  
pp. 1987-1990
Author(s):  
Jian Hua Yi ◽  
Zhen Bao Zhu ◽  
Yuan Fang Wu

The adsorption kinetics of purple cabbage pigment (PCP) on LSA-21 macro porous adsorbent resin were studied at different adsorbent resin concentrations (1, 2, 4, 8 g adsorbent resin per liter of purple cabbage extraction solution) for the temperature range of 20~50°C. The results showed that the adsorption of PCP in purple cabbage extraction solution onto LSA-21 macro porous adsorbent resin is highly in agreement with both Langmuir and Freundlich models. Heat of adsorption (ΔH) value of 11.976 kJ/mol indicates the endothermic adsorption process. A decrease of Gibbs free energy (ΔG) with temperature increase also indicates the spontaneous nature of the process.

2014 ◽  
Vol 809-810 ◽  
pp. 907-911
Author(s):  
Jun Long Wang ◽  
Jie Hou ◽  
Ting Jiang ◽  
Yong Jun He ◽  
Yao Dong Liang

Dry waters with an average diameter of 82 μm were prepared by a high speed mixed route. The formaldehyde absorption kinetics of dry waters was investigated by simulating indoor formaldehyde pollution in glass chamber. The results showed that pseudo-second order model could be used to simulate the adsorption process; the adsorption rate was highest in the initial 60 minutes; when the adsorption lasted for 180 minutes, the adsorption reached equilibrium.


2020 ◽  
Vol 23 (10) ◽  
pp. 370-376
Author(s):  
Thamrin Azis ◽  
La Ode Ahmad ◽  
Keke Awaliyah ◽  
Laode Abdul Kadir

Research on the equilibrium and adsorption kinetics of methylene blue dye using tannin gel from the Tingi tree (Ceriops tagal) has been carried out. This study aims to determine the capacity and adsorption kinetics of tannin gel against methylene blue dye. Several parameters, such as the effect of contact time, pH, and methylene blue dye concentration on adsorption, were also studied. Based on the research results, the optimum adsorption process is a contact time of 30 minutes and a pH of 7. The adsorption capacity increased to a concentration of 80 mg/L with a maximum adsorption capacity (qm) of 49.261 mg/g. The adsorption process follows the pseudo-second-order adsorption kinetics model and the Langmuir isotherm model.


2018 ◽  
Vol 29 (2) ◽  
pp. 103-109 ◽  
Author(s):  
Habibat Faith Chahul ◽  
Gloria Ihuoma Ndukwe ◽  
David Ogwu Ogwu

Abstract The dissolution of aluminum alloy AA 1060 in 0.5 M and 1.0 M HCl was investigated using thermometric measurements. The reaction number of the aluminum coupons varied linearly with the concentration of the acid. Addition of Napoleonaea imperialis seed extract to the dissolving aluminium coupons lowered the reaction number in both concentrations of HCl by inhibiting the dissolution process. The inhibition efficiency of Napoleonaea imperialis seed extract was enhanced to a considerable extent in the presence of iodide ions with the synergistic parameter S > 1. The adsorption of Napoleonaea imperialis extract on the aluminium surface best aligned with the Langmuir adsorption isotherm model. The values of the free energy, ΔGadsfor the adsorption process revealed the process to be spontaneous and physisorptive.


2012 ◽  
Vol 12 (1) ◽  
pp. 28-34 ◽  
Author(s):  
Susy Yunita Prabawati ◽  
Jumina Jumina ◽  
Sri Juari Santosa ◽  
Mustofa Mustofa ◽  
Keisuke Ohto

A research has been conducted to investigate the capability of a series of novel calix[6]arenes-based polymers: poly-monoallyloxycalix[6]arene (2a), poly-monoallyloxypenta-estercalix[6]arene (2b) and poly-monoallyloxypenta-acidcalix[6]arene (2c) for trapping of heavy metal cations such as Cd(II), Cu(II) and Cr(III). The existence of active hydroxy group (-OH) and with a tunnel-like structure of the polymers, caused the polymers can be used as adsorbents for heavy metals. The adsorption process was carried out in batch method in the variation of acidity (pH), contact time and initial concentration of metal ions. The results showed that the amount of adsorbed metal increased with the increasing of the pH of metal solution. For these three polymers, the amount of metal ions Cd(II), Cu(II) and Cr(III) adsorbed was optimum at pH 7, 6 and 5 respectively. The optimum contact time for Cd(II) and Cu(II) was 120 min, while that for Cr(III) was 60 min. Study of the adsorption kinetics showed that the adsorption of Cd(II), Cu(II) and Cr(III) using polymer 2a followed kinetics model of Ho. For adsorbent 2b and 2c, the adsorption kinetics of Cd(II) and Cr(III) also followed kinetics model of Ho while for the Cu(II) followed Lagergren kinetic models. Isothermal studies showed that the adsorption of metal ions on all adsorbents tend to follow the Langmuir isotherm. The adsorption energies of the three adsorbents were higher than 23 kJ/mole and polymer 2c has the largest adsorption capacity for Cr(III).


2011 ◽  
Vol 396-398 ◽  
pp. 592-595 ◽  
Author(s):  
Ying Hua Song

Experiments were carried out to study the adsorption kinetics of grape seed procyanidins onto macroporous resin HZ818 from aqueous solutions.The effects of temperature,initial concentration and agitation on the adsorption kinetics have been investigated.Both the Lagergren-first-order equation and intra-particular diffusion model were used to describe the adsorption mechanisms. And the adsorption process were affected both by film diffusion and by intra-particle diffusion.The intra-particle diffusion rate constants increase with an increase in temperature,initial concentration and agitation speed.


Author(s):  
Daniel P. da Silva ◽  
Samuel G. F. dos Santos ◽  
Isneider L. Silva ◽  
Hellismar W. da Silva ◽  
Renato S. Rodovalho

ABSTRACT Bitter melon (Momordica charantia L.) is a versatile plant that can be consumed as a food and has therapeutic applications. Studying its drying process is important to maintain their leaf quality during storage. The objective of this study was to evaluate the drying kinetics of bitter melon leaves and determine their thermodynamic properties. The leaves were placed in polyethylene trays and subjected to drying in an oven at temperatures of 20, 30, 40, and 50 °C until reaching hygroscopic equilibrium. The experimental data were fitted to several non-linear regression models to characterize the drying process. The Arrhenius model was used to obtain the coefficients of diffusion and the activation energy, which were used to calculate the enthalpy, entropy, and the Gibbs free energy. Midilli and Page were the best models to represent the drying kinetics of bitter melon leaves at temperatures of 20, 30, 40, and 50 °C. Increases in the drying air temperature increased the Gibbs free energy and water diffusivity in the interior of the leaves. Enthalpy and entropy decreased as the temperature was increased.


1991 ◽  
Vol 10 (5) ◽  
pp. 292-293 ◽  
Author(s):  
D. Jayaraman ◽  
C. Subramanian ◽  
P. Ramasamy

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