Study of Kinetics and Adsorption Equilibrium Employing Chemically Modified Coconut Shell for the Removal of Pb(II) from Synthetic Bath

Abstract

Currently, the industrial sector that employs lead metal in its production, such as the manufacture of cable linings, building elements, pigments, soft welds, and ammunition has caused great contamination in industrial effluents. Faced with these problems, several methods have been applied to reduce the concentration of this toxic metal. The objective of this work is to obtain a low-cost biosorbent with a capacity to remove Pb(II) ions. The modification was through a controlled polymerization reaction in sulfuric medium employing formaldehyde as the starting reagent. The Langmuir, Freundlich, and Temkin models adequately described the adsorption process. They indicated that the modified adsorbent removed Pb (II) with good efficiency and performance. The adsorption capacity of the biosorbent was found to be 120.48 mg.g-1 which is higher or comparable to the adsorption capacity of various adsorbents reported in literature. The adsorption kinetics indicated that equilibrium was reached within 30 min for the conditions studied and that intrapore diffusion is the limiting step of the Pb (II) adsorption process. The results indicated that CCFP has the high potential for removal of Pb (II) in water.

Pb(II) Ion Removal Potential in Chemically Modified Ziziphus joazeiro Barks

“…According to Table 3 and Figure 2 , the WW, N and EE adsorbents have excellent fit and very low error, in addition to the direction of the straight pointing to origin and intercepts tending to zero. Considering the interval until the time of 16 min—WW, 8 min—EE and 30 min—N, the diffusion inside the pores has its contribution in the control of the adsorption process, with particle transit occurring without the interference of the film that was still formed [ 73 ].…”

Effect of synthesis method of LaNiO3 type materials with perovskite structure on their features and in the methylene blue dye removal from aqueous media

“…It can be seen from the data in Table 3 that α values are low, indicating a low dye removal rate along the confirming a high amount of time for equilibrium to be achieved during testing as shown in Figure 4. The highest β values are for LN-G9 and LN-CCH9 materials, consequently lower dye removal efficiency due to the greatest desorption [32]. This fact can be explained according to the average crystallite size of the materials (Table 1).…”

Avaliação do perfil cinético e do equilíbrio de adsorção de Cr(III) pelas sementes de Moringa oleifera aplicadas em sistemas aquosos

“…Nesse contexto, a etapa limitante da velocidade de adsorção é controlado através de forças de valência ou troca de elétrons entre o analito metálico e o material adsorvente, principalmente quando o adsorvato se encontra em baixas concentrações. De acordo com vários estudos reportados na literatura, a cinética de adsorção de pseudo-segunda ordem tem sido o modelo que mais se adequa na adsorção de íons metálicos empregando materiais ligno-celulósicos como adsorventes [20][21][22][23] . torna a aumentar à medida que a quantidade substância adsorvida também aumenta.…”