Adsorption of 2,4-Dichlorophenol and Phenol from Aqueous Solutions by Silicate Sorbent

The adsorption of phenol and 2,4-dichlorophenol by diatomite sorbent SMD-Sorb from aqueous solutions is studied. Scanning electron microscopy and energy dispersive X-ray spectral analyses are performed to determine the surface morphology and elemental composition of SMD Sorb diatomite. The specific surface area and total pore volume of the adsorbent are measured via the dynamic low-temperature adsorption of liquid nitrogen. The values of sorption capacity (for phenol and 2,4-dichlorophenol), bulk density, moisture content, and water absorption are estimated. It is shown that the sorbent has fairly low adsorption capacity with respect to the considered substances. The parameters of adsorption equilibria in the surface layers of the studied sorbent are calculated: i.e., the distribution coefficient, limiting adsorption, Henry constants, change in Gibbs energy, adsorption coefficient, and degree of filling, depending on temperature.