Comparison Study on Adsorption and Removal of Antimony from Acidic Aqueous Solution by Activated Carbons and Machine-Made Charcoal

Abstract

Adsorption effects of three kinds of activated carbons and a type of machine-made charcoal on the removal of antimony from acidic aqueous solution were investigated and compared. With an initial antimony solution concentration of 1000 μgL-1, the antimony adsorption by selected adsorbents were found to descend in the following order: machine-made charcoal (52.4%) > coconut activated carbon (42.6%) > coal based activated carbon (31.1%) > apricot stone based activated carbon (24.6%). The machine-made charcoal has the best adsorption capacity with a maximum adsorption values of 523.76 μgL-1. Five kinetic models were used for the fitting of the process of antimony adsorption, including Elovich, parabola diffusion, second order, first order and double-constant. Results showed that parabola diffusion and double-constant rate equation were the most suitable models in describing the relationship of antimony adsorption with time in acidic aqueous solution, implying that the adsorption kinetics of the antimony by the selected adsorbents in water might be a surface diffusion. Three adsorptive capacity indicators (iodine number, methylene blue number and phenol number) were determined in this paper. However, machine-made charcoal, which has a relatively high adsorption capacity, is of the lowest levels of the adsorptive capacity indicators. Thus, some complex mechanisms might be involved for the antimony adsorption by the machine-made charcoal, consequently considering the mechanism for the adsorption of antimony by the charcoal has not been verified, a further study still needs to be done.

The Use of Iron-Based Sorption Materials and Magnetic Fields for the Removal of Antimony from Water

“…A number of experiments and model studies of the adsorption of arsenic and other heavy metals are described in various publications [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. These studies describe sorption processes at different pH values, initial heavy metal ion concentrations in water, solid/liquid ratio, particle size of a sorption material, filtration rate, temperature and composition of water to be treated (concentration of iron, manganese, phosphorus, silicon, fluorides, sulphates, organic matter, etc.…”

Enhanced oxidative and adsorptive capability towards antimony by copper-doping into magnetite magnetic particles

“…S1 †), and this supported the reduction of Cu(II) to that with lower chemical valence, i.e., Cu 0 , Cu I . Furthermore, the thermodynamic calculation also indicated that Sb(III) may be oxidized to Sb(V) by Cu II , and the possible chemical reactions eqn (11) and (12) are given as follows: 3 as the main Sb(III) species at pH 7.0 (Fig. S3 †).…”

“…It is widely considered as one of the best available technologies for medium-and smallscale systems. 10 Conventional adsorbents such as activated carbon, 11 aluminum-based adsorbent, 12 and iron-based adsorbent 13 have been developed for Sb adsorption. However, their adsorptive capacity is not as high as expected, and the high operating costs of solid-liquid separation process which hinders their large-scale applications.…”