Utilization of New Activated Carbon Derived from Oak Leaves for Removal of Crystal Violet from Aqueous Solution

Low-cost Adsorbents Derived from Agricultural By-products/Wastes for Enhancing Contaminant Uptakes from Wastewater: A Review

“…The equilibrium has occurred by agitation at 130 rpm during contact time of 20 min, leading to a sorption percentage of 87.8%. In terms of time creating the equilibrium, the data obtained can be obviously seen as shorter in contact time than in the batch process conducted at 90 rpm [13]. In the process of dye colour adsorption, initially the dye molecule has to first encounter the boundary layer effect and then it has to diffuse from the boundary layer film onto adsorbent surface and then finally it has to diffuse into the porous structure of the adsorbents.…”

“…The percentage of adsorption increased with increases in adsorbent dosage, but the amount of molecules adsorbed per unit mass of adsorbent decreased [13]. As the amount of adsorbent increases, this definitely enhances the increase in the number of adsorption sites and thus increases the adsorbent surface area.…”

“…In the United States, about 30 million tons of oak leaves are collected and burned every year. A new activated carbon from oak l. dead leaves as low-cost adsorbent has been produced [13]. In India, national walnut production oscillates between 40,000 to 45,000 tons per year, and the process involved to obtain unshelled walnuts generates more than 25,000 tons of shell, and approximately 11,000 tons of almond shell waste every year [56].…”

“…Sorbents such as AC can be manufactured from both agricultural by-products and wastes [16], in addition to industrial by-products and wastes [14], while sorbents in the form of unprocessed or semi-processed agricultural by-products/wastes such as dry plant leaves can be found in abundance in public gardens, national forests [13], and private farms [59] as a result of natural annual falling withered leaves in the autumn; they are also called forestry wastes. Waste or spent tea leaves are also known as lowcost biologically originated and have been recommended as novel adsorbents for the removal of toxic HMs such as Pb(II) [60], Cu(II) [61], and some organic pollutants (e.g., pesticides, SD, etc.)…”

“…These wastes can be classified into two groups. One belonging to those residues remaining in the field after harvest or autumn season where leaves wither and fall, for example tree fronds [12] and oak tree (L.) dead leaves [13]. The other group can belong to by-products of industrial processing, for example date stones [14][15], olive stones [16], and tea leaves [17][18].…”