|Ultima descărcare din IBN:|
| SM ISO690:2012|
GOREACIOC, Tatiana; NASTAS, Raisa; LUPASCU, Tudor; RUSU, Vasile. Removal of nitrite ions from natural water by using ag-5. In: Ecological and environmental chemistry 2017The 6th International Conference. 2-3 martie 2017, Chișinău. Chisinau, Republic of Moldova: Academy of Sciences of Moldova, 2017, p. 104.
|Ecological and environmental chemistry 2017 2017|
Conferința "Ecological and environmental chemistry 2017" |
Chișinău, Moldova, 2-3 martie 2017
The purpose of this work was to study the removal of nitrite ions from water by using commercial active carbon AG-5. The effect of surface chemistry (functional groups) of active carbon on the nitrite ions adsorption/removal efficiency was investigated. Surface chemistry of active carbon has been modified by oxidation with nitric acid and characterized by Boehm titration method and IR spectroscopy. Obtained results show an increase of adsorption capacity for nitrite ions after active carbon oxidation (AG-5ox) by about 8 times. The experimental data of adsorption isotherms have been analyzed using the Langmuir and Freundlich isotherm models. Removal of nitrite ions from natural underground water (village Isacova, district Orhei, Republic of Moldova) was investigated by using laboratory installation (semipilot installation) provided with an air bubbler and recovery flask. Underground water had initial concentration of nitrite ions of 7.3 mg/L, nitrate ions of 5.9 mg/L and pH value 8.3. The efficiency of adsorbents was estimated by studying the kinetics of the process, being monitored the concentration of nitrite and nitrate ions, as well as pH value. Comparative studies of efficiency of carbonaceous adsorbents highlight the adsorbent AG-5ox modified by oxidation with nitric acid. The results showed that the recommended process, by using carbonaceous adsorbent AG-5ox, ensures 100% efficiency for the removal of nitrite ions from model solution and 75% from natural underground water.