Design of a multi-stage stirred adsorber using mesoporous metal oxides for herbicide removal from wastewaters

Optimization of Removal Efficiency and Minimum Contact Time for Cadmium and Zinc Removal onto Iron-modified Zeolite in a Two-stage Batch Sorption Reactor

“…1 shows the schematic diagram of the two-stage batch sorption process. 7,13,14,[18][19][20] To design a two-stage batch sorption system, the concentration of metal ions was reduced from C o to C 1 in stage 1, and from C 1 to C 2 in stage 2. At the initial time, t = 0, the amount of sorbent was added with the solid-phase concentration, q o equal to zero (as fresh sorbent is added), and finally the metal concentration on the sorbent increased to q t .…”

“…The overall removal percentage of metal ion onto the sorbent in two stages, R represents the sum of values of removal percentages obtained in each stage, R 1 and R 2 , is calculated by using the following equations: [4][5][6][7]14,19,20 ( ) ( )…”

Kinetic Modeling of Multiple Adsorption of Heavy Metal Ions Using Activated Carbon from Nigerian Bamboo for Design of Adsorbers

“…In the removal of chromium(VI) using magnetically modified graphene oxide-chitosan composite, a single stage batch adsorber was proposed for removal of Cr(VI) concentration up to 0.05 mg L −1 [2] while for the removal of Cu(II) from aqueous solutions when clay of the Gulbarga region, Karnataka, India was used as an adsorbent, a two-stage batch adsorber was designed for the removal of Cu(II) from aqueous solutions, which reduced the adsorbent dose by 51% when compared to that of a single-stage adsorption system [3]. Stirred batch adsorbers are often used in adsorption studied because they offer a number of advantages in comparison to fixed bed systems, as they reduce mass transfer resistances, pressure drops and fouling of the sorbent particles [4]. Minimizing the contact time for a fixed percentage of pollution removal using a fixed mass of adsorbent will result in being able to process more batches of polluted wastewater per day, thus enabling the required treatment plant items to be reduced in size, with a decrease in the plant capital cost.…”

Removal of pesticide from wastewater: Contact time optimization for a two-stage batch stirred adsorber

“…On the contrary, the adoption of a three-stage system allows only a limited reduction of adsorbent in comparison to a two-stage system having the same total volume [26]. As far as we know, no other papers have been so far published about the design of stirred adsorption systems for the removal of herbicides [26].…”

“…Several authors, dealing with stirred systems in which the adsorption equilibrium is reached within a short time, or expensive sorbents are to be used, or the adsorption capacity of the adsorbent is small, have obtained the mass of adsorbent and optimized the number of stages of a multi-stage adsorber by using a steady-state analysis: with equilibrium data it is possible to determine the minimum mass of adsorbent required to remove a given amount of herbicide from a given volume of wastewater [9,10,12,13,26,27].…”