Competitive adsorption of reactive dyes from binary mixture by MgAlNO3 - layered double hydroxide

Adsorption of Reactive Black 5 (RB5) and Reactive Orange 16 (RO16) from their binary mixture using MgA-NO3 -layered double hydroxide (MgAlNO3-LDH) was conducted in a batch system. First order derivative spectrophotometric method was used for simultaneous analysis of RB5 and RO16 in binary mixtures. The effect of pH, contact time, and initial concentration were investigated. The results of these analyses showed that adsorption of reactive dyes were optimum at pH 2. Experimental data indicated that between the two reactive dyes in the mixture, RB5 was competitively better adsorbed than RO16 by LDH. Kinetic studies indicated that both pseudo first order and second order kinetic models fitted the experimental data with correlation R2> 0.96.