Metal Adsorbent Prepared from Coir Pith as Agricultural Waste: Adsorption of Zn(II) and Pb(II) from Aqueous Solution

Abstract

Adsorption of Zn(II) and Pb(II) from aqueous solution were studied by using modified coir pith as an adsorbent. The extended adsorption conditions were investigated as a function of calcination temperature, contact time, adsorbent size, initial pH of solution and initial Zn(II) and Pb(II) concentrations. The adsorption capacity increased rapidly in first 5 minute and reached equilibrium in 120 minutes for Zn(II) and 10 minutes for Pb(II). In case of Zn(II); the results showed that the calcination temperature of modified coir pith above 600oC gave the higher adsorption capacity. The sizes of modified coir pith have no effect on the adsorption capacity. The adsorption capacity increased with increasing initial solution pH value. In case of Pb(II); the calcination temperature of modified coir pith showed no effect on the adsorption capacity. The sizes of modified coir pith showed a little effect on the adsorption capacity. The adsorption capacity increased with increasing of initial solution pH value up to pH of 3 and then stable. The results also corresponded with the Langmuir and Freundlich isotherms and pseudo second order kinetic adsorption models. The modified coir pith gave a higher Zn(II) and Pb(II) adsorption capacity of 29.33 mg Zn(II)/g adsorbent and 36.50 mg Pb(II)/g adsorbent, respectively.

Application of Kenaf Bast Fiber to Adsorb Cu(II), Pb(II) and Zn(II) in Aqueous Solution: Single- and Multi-metal Systems

“…The adsorption process can occur at any sites of the adsorbent due to randomly distribution of active sites and their energies [51], [53]. The linear form of the Freundlich isotherm model is given as equation (4) (4) where n is the Freundlich constant that representing adsorption intensity and K F (mg/g) related to the adsorption capacity. The linear plot of log q e against log C e will give values of K F and n.…”

“…Industrial activities such as electroplating, alloys and acid batteries manufacturing and, electrical components and paints manufacturing are the main sources of heavy metals [3], [4].…”

“…They cannot be degraded or destroyed naturally therefore persist in our environment [5], [6]. Heavy metals are dangerous especially when they contaminate the aquatic ecosystem [7] thus increasing risks of diseases such as insomnia, nausea, anemia, Wilson's disease, liver damage, skin irritations to human [4], [8].…”

Bio-adsorbent derived from papaya peel waste and magnetic nanoparticles fabricated for lead determination

“…Recently, employment of adsorbents originating from biomaterial and agricultural waste has become an interesting approach in adsorption methodology due to their natural capability and inherently environmentally friendly characteristics [26,27]. These bio-adsorbents have also been used successfully for heavy metal analysis in water decontamination processes [4,28,29].…”