Adsorption of Acid Red 88 from Aqueous Solution by Calcined Layered Double Hydroxides

The removal of acid red 88(AR88), an anionic dye, from aqueous solution by calcined Mg/Al LDHs(LDO) was investigated. The effect on the decolorization rate of AR88 was studied of initial dye concentration, amount of adsorbent, initial pH values, temperature and competitive anions. The solid LDO, both fresh and after removal of AR88, was characterized by XRD and infrared spectroscopy. The results of adsorption indicate that LDO could be used to remove high concentration anionic dyes and the maximum capacity of AR88 at equilibrium (Q(e)) and percentage of adsorption (eta/%) with a fixed adsorbent dose of 1.0 g center dot L-1 are found to be 1999.0 mg center dot g(-1) and 99.95%, respectively, when AR88 concentration, temperature, pH value are 2 000 mg center dot L-1, 288 K, and 10 similar to 11, respectively. The removal rate of AR88 is above 90% for LDO after four cycles indicating the feasibility of LDO regeneration.