On the Adsorption Mechanisms of Copper Ions over Modified Biomass

Sustainable natural adsorbents for heavy metal removal from wastewater: lead sorption on pine bark (Pinus radiataD.Don)

“…The experimentally observed rate constants for lead sorption at these pulp densities are on the order of 10 −8 l min −1 mol −1 (Table ), which is approximately one to two orders of magnitude higher than the value previously observed for copper ions under otherwise identical experimental conditions . At a pulp density of 5 g l −1 the kinetics observed were too fast to reliably distinguish between first and second order kinetics.…”

“…[16] At a pulp density of 5 g l À1 the kinetics observed were too fast to reliably distinguish between first and second order kinetics. Table 3 shows the results of the EDX elemental analysis of original washed bark and after the sulfuric acid treatment.…”

“…[1,15] Previous research has indicated that the adsorption process can be usefully performed at pH values under which heavy metal ions remain in solution on one hand while high bark pulp densities can be maintained on the other. [2,16] The kinetics of adsorption under these conditions is usually parametrically presented as a function of either the pulp density or the ion concentration. The maximum adsorption capacity depends in a complex manner on the properties of both the ion solution and the substrate.…”

Kinetic and Isotherm Adsorption Studies of Methylene Blue on Sulfuric Acid Treated Spent Grated Coconut (<i>Cocos nucifera)</i>

“…Chemical activation by H 2 SO 4 in particular is widely used as it improves pores development [8]. The treatment method was adapted from Montes et al [9] and Lin et al [10] with some modification where HSGC was mixed in the ratio of 3.0 g of HSGC to 50 mL, 2.0 M H 2 SO 4 (3:50, w/v). The concentration of 2.0 M H 2 SO 4 was chosen after the optimization studies done for a series of H 2 SO 4 concentration ranging from 0.5 to 5.0 M. The mixture was stirred continuously at 480 rpm and at temperature 373 K for 3 h, cooled to room temperature (298 K), and washed twice with 200 mL of distilled water.…”

Evaluation of an Adsorption–Desorption Process for Concentrating Heavy Metal Ions from Acidic Wastewaters

“…The efficiency of an overall wastewater treatment process is dependent on the type of natural sorbent employed, the nature of the metal ion to be bound to it, the initial dissolved metal ion concentration, the pH, the temperature, the pulp density, the cell design (batch, column, etc. ) and the contacting time (Krosshavn et al 1993;Montes et al 2006). One of the most popular techniques for wastewater treatment, involving small and medium water flow rates, is the utilisation of natural and synthetic sorbents, such as ion-exchange resins (Jensen et al 2005;Bailey et al 1999;Zamzow et al 1990).…”