Health and environment
Ahmad Alahabadi; Abolfazl Rahmani Sani; Zahra Rezai; Mahnaz Torabi
Volume 25, Issue 4 , September and October 2018, , Pages 528-536
Abstract
Background and Background and goal : The attendance of humic acid in water resources is the main health problems of many Societies. There are various methods for decreasing or removing of humic acid. Of these absorbed is considered an effective method to remove it. SO Agriculture wastes were used for ...
Read More
Background and Background and goal : The attendance of humic acid in water resources is the main health problems of many Societies. There are various methods for decreasing or removing of humic acid. Of these absorbed is considered an effective method to remove it. SO Agriculture wastes were used for preparation of activated carbons by chemical activation using Ammonium chloride.Method: In this study, the standard Merck carbon and carbon produced from plant waste used as adsorbents and adsorption experiments were performed in batc. Adsorption of humic acid (HA) on SAC and NAC as a function of solution initial pH (2-10), adsorbent dosage (0.1-1 g/L), contact time (5-50 min), concentration (5-20 mg/L), on the adsorption capacity, the two-parameter equilibrium models (Langmuir and Freundlich equations) were debated. Result: The result showed that the pH effect at removal humic acid is an important parameter, and isotherm showed that the adsorption Followed of the Langmuir isotherm. Also it was found that the capacity of absorb can be markedly effected by carbon type. That it was 238, 294 , 250 mg/g For carbons Merck, Sycamore and steel respectively.Conclusion: Carbon prepared from Steel due to very high capacity could be effective for removal humic acid from aqueous solution.
Mahnaz Torabi-Hokmabadi; Ahamd Alahabadi; Abolfazl Rahmani-Sani; Somayyeh Zarei-Tazarghi; Hamidreza Karimi-Sani; Mohamadreza Behrozikhah
Volume 23, Issue 3 , July and August 2016, , Pages 504-515
Abstract
Background Painkillers such as diclofenac are widely used in human medicine and veterinary medicine. Because of their excretion into water resources and subsequent environmental hazards, their removal from the waters and wastewaters is essential. Since, these drugs cannot undergo biodegradation, an advanced ...
Read More
Background Painkillers such as diclofenac are widely used in human medicine and veterinary medicine. Because of their excretion into water resources and subsequent environmental hazards, their removal from the waters and wastewaters is essential. Since, these drugs cannot undergo biodegradation, an advanced treatment such as adsorption method must be applied for their removal and one of the best adsorbents in this regard is activated carbon. This study aimed to investigate the removal of diclofenac contaminant by NH4Cl-induced activated carbon.Materials & Methods Activated carbon produced from agricultural wastes was impregnated with ammonium chloride (NH4Cl) and activated at 800°C. The experiments were conducted in a closed system using a magnet stirrer at 100 rpm. In this investigation, the effects of several variables, namely adsorbent concentration, contact time, pH, and temperature, on the removal of diclofenac were evaluated. Then, isotherms and adsorption thermodynamic were explored. We used DR 5000 spectrophotometer model for drug analysis with the wavelength of 275 nm.Results The produced NAC (NH4Cl-induced activated carbon), having the special surface of 1029 m2/g and pores volume of 2.46 nm, was able to remove 0.81% of diclofenac from a solution of 50 mg/L at the sorbent concentration of 0.8 mg/L, pH 6, in 20 minutes time. The equilibrium adsorption experiments showed that the absorption of diclofenac on NAC followed the Longmuir model and the absorption capacity was 212.5 mg/g. Using the diclofenac concentration of 50 mg/L and other optimal conditions, thermodynamic studies of diclofenac absorption on NAC showed that the amount of drug removal increased from 73% to 95% with increasing temperature from 10°C to 40°C. Conclusion NAC can be used as a convenient and inexpensive adsorbent for the removal of diclofenac and other drug compounds from polluted waters and wastewaters.