Removal of metronidazole antibiotic from aqueous solution by ammonia-modified activated carbon: adsorption isotherm and kinetic study

Abstract

This article was aimed at investigating the removal of metronidazole (MNZ) from aquatic solutions by modified activated carbon (MAC) with amine groups. The effect of various parameters on the adsorption rate such as the initial pH, adsorbent dose and initial concentration of MNZ and contact time were scrutinized. MAC was characterized by Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller techniques. The obtained results illustrated that under the optimum conditions (pH = 3, contact time = 50 min, initial MNZ concentration = 5 mg/L and MAC dose = 0.5 g/L), the maximum adsorption efficiency was 95%. Furthermore, the kinetic studies indicated the applicability of the pseudo-second-order kinetic model, whereas the adsorption isotherm fitted well with the Freundlich model (0.996), and the maximum adsorption capacity was 66.22 mg/g. The SBET and the total pure volume of MAC were 706.92 m2/g and 0.532 cm3/g, respectively. Also, the regeneration tests demonstrated that MAC had good stability after five cycles (73%). It can be concluded that MAC, as an effective adsorbent, has a high ability to remove MNZ from aqueous solutions.

Review: Ammonia adsorbent development for white-shrimp ponds

“…If you use bagasse fly ash, only transportation costs are needed. Many researchers have used bagasse fly ash as an adsorbent for various pollutants from liquid waste, including metals [33][34], organic [35]- [37], and COD [38]. But unfortunately, the efficiency of the adsorbent on ammonia removal using bagasse fly ash is only around 45.72% [21].…”

Improving the Radon Adsorption Capacity of Activated Carbon by Liquid Nitrogen Modification

“…These nitrogen adsorption isotherms are type I according to IUPC classification and indicate there are abundant micropores in all samples. When the partial pressure P/P0 > 0.4, a slight hysteresis ring appears, which suggests that samples have a small amount of mesopores [23][24][25].…”

“…These nitrogen adsorption isotherms are type I according to IUPC classification and indicate there are abundant micropores in all samples. When the partial pressure P/P0 > 0.4, a slight hysteresis ring appears, which suggests that samples have a small amount of mesopores[23][24][25].As a rule, the macropores are conducive to radon transport. The mesopore can foreshorten the distance between the radon and the micropores, which is conducive to improving the adsorption efficiency.…”

Adsorption and separation of Cs(I) and Ba(II) from aqueous solution using zinc ferrite-humic acid nanocomposite

“…Natural exchanger materials, such as zeolites, different types of clay, and oxide materials, have been investigated and applied to remove radioactive wastes. Also, synthetic exchangers such as composite materials, polymeric materials, and porous materials have been of greatest interest for removing wastes [9][10][11][13][14][15][16][17] .Magnetic adsorbents get the feature of being efficiently recovered from the aqueous system by utilizing a magnetic field [18][19][20][21][22][23][24][25][26] . Spinel ferrites possess unique chemical and physical features that distinguish them from their bulk form; hence they are often utilized as adsorbents.…”

“…Natural exchanger materials, such as zeolites, different types of clay, and oxide materials, have been investigated and applied to remove radioactive wastes. Also, synthetic exchangers such as composite materials, polymeric materials, and porous materials have been of greatest interest for removing wastes [9][10][11][13][14][15][16][17] .…”