The prepared adsorbent (EMDN) was stored in an air tight container.
The topography and the elemental composition of EDTA modified dika nut (EMDN) was studied using a FEIESEM quanta 200 for SEM and EDX.
In order to investigate the leaching/desorption of RhB from EMDN, deionized water, 0.1M HCl and 0.1M CH3COOH were used as desorbing agents.
Table 1 depicts the physicochemical characteristics of EMDN, the bulk density, ash content and moisture content were found to be low, low moisture content suggest that adsorbent is not diluted hence, additional weight of adsorbent is not required.
The BET surface area is low, this is a characteristic of agricultural waste  FT-IR spectrum of EMDN (figure not shown) before dye adsorption shows strong adsorption bands at 1024 cm-1, 1232 cm-1, 1731 cm-1, 2907 cm-1 and 3338 cm-1 their assignment is as listed in Table 2.
FTIR spectral characteristics of EMDN before and after RhB adsorption
Figure 1 shows the SEM analysis of EMDN, the surface of EMDN before dye adsorption was smooth and with numerous pores.
2 depicts the effects of pH on RhB adsorption onto EMDN, adsorption percentage was observed to increase as the initial solution pH increased and goes to equilibrium after pH 6.
Effects of adsorbent dosage on RhB uptake onto EMDN.
Effects of contact time and initial adsorbate concentration on RhB uptake onto EMDN.