Study of CaCl2 as an agent that modifies the surface of activated carbon used in sorption/treatment cycles for nitrate removal

Abstract

-The efficiency of the application of a chemically-modified activated carbon surface was investigated. The purpose of this study was to examine the effect of treatment with CaCl 2 solution at a concentration of 2000 mg.L -1 on the sorption of nitrate ions from aqueous solutions in successive sorption/t reatment cycles. The sorbent was initially subjected to chemical treatment with CaCl 2 and subsequently to the sorption process. Nine sorption cycles were performed. The concentrations of nitrate ions in the solution were measured by UV-Vis spectrophotometry before and after sorption. The results show that treatment with CaCl 2 caused a significant increase in the percentage removal for each treatment step, reaching a removal rate of 80% of nitrate in the solution after nine cycles.

Development of Newer Adsorbents: Activated Carbons Derived from Carbonized Cassia fistula

“…EDX data show significant proportions of K, Ca, and Fe, while XPS shows presence of additional elements such as Si, Mg, Na in varying amounts as per the nature of treatment.These heteroatoms can influence the acidic and basic properties of the carbon surface and hence affect the adsorption behavior . For example, the presence of Ca may impart positive character and enhance the treatment efficiency for specific pollutants or increase the mesopore volume which is in agreement with Table showing CF-450 with the least micropore volume (0.005 cm 3 /g) and highest Ca content of 2.62%, while Fe is known for its ability to introduce acidic functional groups . The presence of heterogeneous elements like Mg (0.09–0.66 ppm) and Ca (0.51–1.62 ppm) and transition element like Fe (0.02–0.21 ppm) in the carbon matrix of the five adsorbents was also confirmed by ICP-OES analysis (Spectro-Arcos, ARCOS-FHS-12).…”

Adsorptive degradation of hexavalent chromium from aqueous solution using coconut shell as a green adsorbent

“…The ground and dried coconut shells were treated with CaCl 2 for chemical activation of the adsorbent. The chemical activation of the adsorbent was carried out using the following method adopted by Zanella et al, 2014 37 . A 15% CaCl 2 solution was prepared by adding 45 g of CaCl 2 in 300 ml of distilled water.…”

“…The chemical activation of the adsorbent was carried out using the following method adopted by Zanella et al, 2014. 37 A 15% CaCl 2 solution was prepared by adding 45 g of CaCl 2 in 300 ml of distilled water. The slurry part of the powder was adequately mixed and was kept in an oven at 120 C for 24 h until the mixture became thick dry black powder.…”

Removal of Phenol from Olive Mill Wastewater Using Activated Rice Husk

“…The chemical activation procedure involved immersing a 25.0 g of RH in 25% of CaCl 2 solution for 24 hrs. After that the resulting activated carbon was filtered, washed with distilled water, and dried in an oven at 105 °C for 1 hour (Zanella et al, 2014).…”