Activated carbons from coffee husk: Preparation, characterization, and reactive red 195 adsorption

Abstract

Activated carbons are prepared from coffee husks by chemical activation with ZnCl2 and are characterized by employing Brunauer, Emmett and Teller, scanning electron microscopy, Fourier-transform infrared spectroscopy, and Boehm titrations. The effects of ZnCl2/coffee husks, activation temperature, and activation time are studied, and the results show that the sample ACZ3-600-2 has a high surface area of 1383 m2 g−1, a high pore volume of 1.6482 cm3 g−1, and numerous surface functional groups. The adsorption of reactive red 195 onto the prepared coffee husk activated carbon can be well-described by the pseudo-second-order kinetic model and is found to be controlled by film diffusion followed by intra-particle diffusion. The adsorption isotherm data obtained at 10–40 °C are analyzed and found to follow the Sips model at lower temperatures (10 and 20 °C) and the Redlich–Peterson model at higher temperatures (30 and 40 °C). The obtained thermodynamic parameters (Δ G° < 0, Δ H° = 33.487 kJ mol−1, and Δ S° = 202.30 J K−1 mol−1) suggest that the adsorption of reactive red 195 onto the prepared activated carbon is spontaneous, endothermic, and demonstrates an increasing of randomness at the adsorbate–adsorbent interface. The investigated results show that coffee husk activated carbon is an efficient adsorbent for the removal of reactive red 195 from aqueous solutions.

Adsorptive performance of bentonite-chitosan nanocomposite as a dual antibacterial and reusable adsorbent for Reactive Red 195 and crystal violet removal: kinetic and thermodynamic studies

“…In order to reveal the preferability of the as-prepared nanocomposite for the RR and CV dyes removal over the reported ones, a comparative study has been constructed between the prepared nano-adsorbent and the other previously published ones as indicated in Tables 6 and 7. As indicated, the exploited nano-adsorbent displayed the highest removal efficiency for both RR and CV dyes [65][66][67][68][69][70][71][72][73][74][75][76][77][78][79] using lower adsorbent dose [67,68,70,[73][74][75][76][77][78][79] after shorter contact time [66][67][68][69][70][71][73][74][75][76][77] than the reported ones affirming its superior performance for the removal of the dyes under investigation.…”

Characteristics and performance analysis of activated carbons derived from different precursors and activators for waste water adsorption

“…The adsorption process needs a substance with the capacity to adsorb. One of the greatest adsorbents for removing pollutants from waste water is activated carbon [15,16]. Activated carbons made from coconut shell [9], acacia erioloba seed pods [10], agricultural waste [11], corn stigmata fiber [12], and algae [13] produced by different activation methods have been used for methyl blue adsorption.…”

Adsorption of methylene blue dye onto modified activated carbon produced from groundnut shells

“…Various industrial processes that produce products ranging from textile, plastic, paper, cosmetics, dyestuffs, ink, tannery, to leather starting materials use cationic dye especially methylene blue as coloring agent (Yaseen andScholz, 2018, Genetie, 2020). The release of such dyes into the aqueous environment may cause damage to the aquatic system and food chain (Gupta, 2009, Yaqub et al, 2014, Harshananda et al, 2020, Jawad et al, 2021, Thuy et al, 2021. Hence, the treatment of industrial effluents are required in accordance with legal requirements to protect human health, sources of livelihood, and the environment.…”