Efficient anionic dye adsorption on natural untreated clay: Kinetic study and thermodynamic parameters

Silica Gels from Coal Fly Ash as Methylene Blue Adsorbent: Isotherm and Kinetic Studies

“…The peaks featured the functional groups of SiO2. Peaks 1, 2, and 3 from all samples can be seen at wavelengths of 465; 700; and 1,085 cm -1 showing sequential bending, symmetrical stretching, and asymmetrical stretching on inter tetrahedral oxygen atom Si -O-Si (siloxane) as the main structure of SiO2 [21]. In addition, the peak at wavelength 1,630 cm -1 (peak 4) and a broad peak at 3,440 cm -1 (peak 7) showed consecutively the characteristic of bending and stretching of -OH attached to the SiO2 frameworks to become silanol group (Si-OH).…”

“…The larger of the value of C was the greater of the effect of the barrier layer. [21] is typed in Equation 7:…”

“…Pseudo-first-order Model by isothermal Lagergren is typed as in Equation 4 [21]: (4) qt and qe are the amounts of adsorbate adsorbed in time t and equilibrium (mg.g -1 ), k1 is a constant pseudo-first-order (min -1 ) and t is the interaction time (min). Determining the value of k1 may be determined by the plot between log (qe-qt) versus t.…”

Anionic and Cationic Dyes Removal from Aqueous Solutions by Adsorption onto Synthetic Mg/Al Hydrotalcite-Like Compound

“…Therefore, in the past few years, there is a growing need to find low-cost, locally available, effective adsorbent for the removal of dyes. The extensive research has been undertaken to study the application of a number of natural resources including solid wastes such as natural and synthetic clay, as dye adsorbents have attracted interests [4][5].…”

Adsorption of Methylene Blue from Aqueous Solution Using Steam-Activated Carbon Produced from <i>Lantana camara</i> Stem

“…As a result, there has been a great interest in developing new adsorbent materials with diverse compositions, properties and functionalities. Although commercial activated carbon is the most widely used adsorbent for dye removal, it is too expensive [9]; consequently, numerous low-cost alternative adsorbents have been proposed including chemically modified sugarcane bagasse lignin [10], pistachio hull waste [11], coffee husk-based activated carbon [12], pine cone [13], rice husk [14], synthetic calcium phosphates [15], natural untreated clay [16], pillared clays [17], and swelling clays [18].…”