Preparation and characterization of bio-safe activated charcoal derived from coffee waste residue and its application for removal of lead and copper ions

Abstract

Activated charcoal was prepared by the pyrolysis of coffee ground waste residues impregnated by phosphoric acid and potassium hydroxide at 600 C. In our study, spent coffee was collected from the university canteen and the prepared activated charcoal impregnated with potassium hydroxide gave the highest surface area of 708.1 AE 0.1 m 2 g À1 , which was determined by using the methylene blue adsorption method. The activated charcoal was characterized by using scanning electron microscopy and Fourier transform infrared spectroscopy. In order to ensure that the activated charcoal produced is bio-safe, all samples were tested for possible toxic substances, including toxic heavy metals by using ICP-OES, and toxic organics such as acrylamide by using chromatography methods. In addition, all samples showed no ecotoxicity towards Escherichia coli and no cytotoxicity toward human HaCaT skin cells. The phosphoric acid activated charcoal demonstrated a high Q max of 95.2 and 38.2 mg g À1 , respectively for lead and copper adsorption. For potassium hydroxide activated charcoal, the values of Q max were found to be 45.4 and 21.2 mg g À1 , respectively for lead and copper adsorption.

Optimisation and characterisation of hydrochar production from spent coffee grounds by hydrothermal carbonisation

“…interesting and distinctive surface morphologies. Raw SCGs exhibit a rough and irregular surface morphology, consistent with those reported in a previous study [57]. In comparison, irrespective of the varying carbonisation conditions, SCGs hydrochars showed distinctive morphologies that suggest the HTC process resulted in a major transformation of SCGs hydrochar surface morphologies.…”

Preparation and Characterization of Nanoporous Activated Carbon Derived from Prawn Shell and Its Application for Removal of Heavy Metal Ions

“…It is widely used in the remediation of industrial waste water and contaminated groundwater [1,2]. Heavy metal pollution is a serious environmental problem [3,4]. Copper is one of the most widely used and most common heavy metals in industrial production activities [5,6,7,8].…”

Porous organic polymer bifunctionalized with triazine and thiophene groups as a novel adsorbent for removing Cu (II)

“…[3][4][5][6][7][8][9] Among the methods, adsorption by porous solid adsorbents has been approved as an economical and efficient method for the removal of toxic metal ions. Many adsorbents, such as mesoporous silica [10][11][12] , porous resin [13,14] and activated carbon [15,16] , have been developed for removing toxic metal ions from polluted wastewater. To facilitate the efficiency of removing toxic metal ions, functional groups, such as carboxyl [17,18] , amine [19] , amidoxime [20] and thiol [12] , have been incorporated into porous adsorbents.…”