Synthesis, SDBS modification and phenol adsorption capability of Mg-Al hydrotalcites

To explore treatment of phenol wastewater, carbonate pillared Mg/Al hydrotalcites and four kinds of modified Mg/Al hydrotalcites with different concentration of SDBS were synthesized by coprecipitation method and characterized by XRD and FTIR respectively. Then the five kinds of Mg/Al hydrotalcites were used as adsorbent to adsorb phenol in solution, in the meantime the adsorption mechanism and influencing factors were investigated. The results show that the adsorption equilibrium time was less than 120min; the adsorption of phenol was in accord with first-order kinetics; the adsorption capabilities of Mg/Al hydrotalcites were proportional to the initial concentration of phenol; the adsorption capabilities of the SDBS modified Mg/Al hydrotalcites were higher than carbonate pillared Mg/Al hydrotalcites, and proportional to the concentration of SDBS used in modification; the adsorption capabilities were higher under weak alkaline condition than neutral condition. However, the adsorption effects were mediocre, so increasing the quantity of adsorbent, using multistage adsorption, and recovering of hydrotalcites should be all taken into consideration, in order to make the treatment of phenol wastewater cost-effective.