Removal of Cadmium(II) from Aqueous Solutions by Calcium Alginate Beads

Cadmium (Cd) is a metal that can negatively interfere with the metabolic systems of living beings. The objective of this work was to evaluate the capacity for cadmium removal in aqueous solutions by immobilized Chlorella sp. in calcium alginate beads. Beads without Chlorella sp. were used as a control. All the treatments were established in triplicate for 80 min, at four concentrations of cadmium (0, 20, 100 and 200 ppm), taking samples of aqueous solution every 10 min, to be read using atomic absorption equipment. The study determined that the treatment of alginate beads with immobilized Chlorella sp. removed 59.67% of cadmium at an initial concentration of 20 ppm, this being the best removal result.

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Synthesis of phosphate-embedded calcium alginate beads for Pb(II) and Cd(II) sorption and immobilization in aqueous solutions

Transactions of Nonferrous Metals Society of China ◽

10.1016/s1003-6326(16)64340-6 ◽

2016 ◽

Vol 26 (8) ◽

pp. 2230-2237 ◽

Cited By ~ 24

Author(s):

Yun-yan WANG ◽

Wen-bin YAO ◽

Qing-wei WANG ◽

Zhi-hui YANG ◽

Li-fen LIANG ◽

...

Keyword(s):

Aqueous Solutions ◽

Calcium Alginate ◽

Alginate Beads ◽

Calcium Alginate Beads

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Thermodynamic, Kinetic, and Equilibrium Parameters for the Removal of Lead and Cadmium from Aqueous Solutions with Calcium Alginate Beads

The Scientific World JOURNAL ◽

10.1155/2014/647512 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 24

Author(s):

Ruth Alfaro-Cuevas-Villanueva ◽

Aura Roxana Hidalgo-Vázquez ◽

Consuelo de Jesús Cortés Penagos ◽

Raúl Cortés-Martínez

Keyword(s):

Aqueous Solutions ◽

Thermodynamic Parameters ◽

Calcium Alginate ◽

Alginate Beads ◽

Second Order ◽

Order Kinetic ◽

Calcium Alginate Beads ◽

Kinetic And Thermodynamic Parameters ◽

Lead And Cadmium ◽

Cadmium And Lead

The sorption of cadmium (Cd) and lead (Pb) by calcium alginate beads (CAB) from aqueous solutions in batch systems was investigated. The kinetic and thermodynamic parameters, as well as the sorption capacities of CAB in each system at different temperatures, were evaluated. The rate of sorption for both metals was rapid in the first 10 minutes and reached a maximum in 50 minutes. Sorption kinetic data were fitted to Lagergren, pseudo-second-order and Elovich models and it was found that the second-order kinetic model describes these data for the two metals; comparing kinetic parameters for Cd and Pb sorption a higher kinetic rate (K2) for Pb was observed, indicating that the interaction between lead cations and alginate beads was faster than for cadmium. Similarly, isotherm data were fitted to different models reported in literature and it was found that the Langmuir-Freundlich (L-F) and Dubinin-Radushkevich (D-R) models describe the isotherms in all cases. CAB sorption capacity for cadmium was 27.4 mg/g and 150.4 mg/g for lead, at 25°C. Sorption capacities of Cd and Pb increase as temperature rises. According to the thermodynamic parameters, the cadmium and lead adsorption process was spontaneous and endothermic. It was also found that pH has an important effect on the adsorption of these metals by CAB, as more were removed at pH values between 6 and 7.

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