scholarly journals Use of Poly(vinyl alcohol)-Malic Acid (CLHPMA) Hydrogels and Chitosan Coated Calcium Alginate (CCCA) Microparticles as Potential Sorbent Phases for the Extraction and Quantitative Determination of Pesticides from Aqueous Solutions

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3993
Author(s):  
Cristian Valdés ◽  
Oscar Valdés ◽  
Daniel Bustos ◽  
Diana Abril ◽  
Gustavo Cabrera-Barjas ◽  
...  

Pesticides are used worldwide to increase crop yields in agriculture. However, their toxicity and accumulation capacity can make them toxic to the environment, animals and humans. In the case of workers chronically exposed to these substances, they must be sampled continuously, so urine is an excellent option. In this sense, this study proposes to use poly(vinyl alcohol)-malic acid hydrogels, and chitosan-coated calcium alginate as new sorbent phases to be used in pesticide determination processes in urine. To better understand the behavior of these materials in the capture and desorption process, molecular dynamics simulations (MDS) were used, and desorption experiments were performed, using mechanical agitation, ultrasound, and pH variation in the desorption process, in order to optimize the parameters to obtain better recoveries. Under the optimal experimental conditions, the maximum recoveries were of the order of 11% (CFN), 3% (KCF), 53% (DMT), 18% (MTD) and 35% (MTL). Although the recoveries were not exhaustive, they are a first approximation for the use of these new sorbent phases in the determination of this type of compound in aqueous solutions and urine.

2021 ◽  
Vol 10 (1) ◽  
pp. 72-83
Author(s):  
Sarina Hanifah ◽  
◽  
Rusnadi Rusnadi ◽  
M. Bachri Amran ◽  
◽  
...  

This work aims to study the removal of lead (II) from aqueous solutions with Ca-Alginate (CA) and Coffee-Calcium-Alginate (CCA). The coffee biomass were successfully prepared as the material to be encapsulated in calcium alginate. The characterization of the synthesized CA and CCA was performed using fourier transform infrared and scanning electron microscopy. The method used was batch study. Various factors which affected adsorption efficiency of lead (II) ions by CA and CCA, such as pH, agitation time, and adsorbent dose were investigated for determination of optimum experimental conditions. The result showed that CA and CCA had significant effects on adsorption of lead (ІІ) ions at pH = 4, agitation time of more than 120 min, and the adsorbent dose was 0.05 gram. Moreover, the Langmuir isotherm model showed that maximum adsorption capacity (qm) was 163.66 mg/g and 176.99 mg/g respectively for CA and CCA. The Langmuir isotherm was better described the adsorption equilibrium. Both of the adsorbent fitted to pseudo second order equations. These results demonstrated that CA and CCA show great potential to remove Pb(ІІ) ions from aqueous solutions.


Polymer ◽  
2021 ◽  
pp. 123960
Author(s):  
Chang Liu ◽  
Xinhong Yu ◽  
Yinghan Li ◽  
Xinyue Zhao ◽  
Quan Chen ◽  
...  

1996 ◽  
Vol 12 (1) ◽  
pp. 55-59 ◽  
Author(s):  
Yoshiaki KURAUCHI ◽  
Tohru OGATA ◽  
Naoyoshi EGASHIRA ◽  
Kazuya OHGA

Sign in / Sign up

Export Citation Format

Share Document