Activated carbon microspheres derived from hydrothermally treated mango seed shells for acetone vapor removal

Abstract

Mango fruit seed shells were used as starting materials to produce activated carbons for the capture of acetone, a typical volatile organic compound (VOC), from gaseous streams. This fruit waste presents high volatiles and low ashes contents, as expected for the lignocelulosic materials commonly used for the preparation of activated carbons. The starting material was hydrothermally treated at 180 or 250 °C for 5 h and the obtained hydrochars were activated with KOH solutions. The carbon samples were characterized by SEM, EDX, TG/DTA, Raman spectroscopy and textural analysis by physisorption. The adsorption capacity and adsorption cycles were investigated by TG. The hydrochars presented spherical morphology and the activated carbons derived from them presented heterogeneous micropore structures allowing to high capacity of acetone vapor removal, namely 472 mg/g, at 30 °C and 363 mg/g, at 50 °C. The results indicate that the adsorption capacity of the activated carbons is directly related to their Dubinin-Astakhov micropore surface areas and microporous volumes determined by NLDFT. The adsorption of acetone vapor showed a pseudo-first order kinetics and both external and intraparticle transport contributed for the overall process. Highly efficient and stable acetone vapor removal was observed over the activated carbons after five cycles.

Exploring the Micropore Functional Mechanism of N2O Adsorption by the Eucalyptus Bark-based Porous Carbon

“…The FTIR spectra before and after adsorption are displayed in Figure . The broad peak at 3700–3200 cm –1 was attributed to the existence of hydroxyl functional groups; the peaks at 1570 and 670 cm –1 corresponded to the stretching vibration of CC on the benzene ring skeleton and the out-of-plane bending vibration of C–H, respectively. , The small peak around 1380 cm –1 represented the symmetric stretching vibration of carboxyl groups and the peak observed near 1020 cm –1 could be ascribed to C–O and C–C tensile vibration . The strong absorption peak near 1167 cm –1 was assigned to the C–O–C stretching vibration .…”

Performance of Gas-Phase Toluene by Adsorption onto Activated Carbon Prepared from Robinia Pseudoacacia L. as Lignocellulosic Material

“…Adsorption capacities varied according to pollutant type and ambient conditions. Andrade et al [48] were investigated VOC removal by activated carbon from mango fruit shells. The adsorption capacity was found at 472 mg/g at 30 °C and 363 mg/g at 50 °C for acetone gaseous.…”

Modification, Production, and Methods of KOH‐Activated Carbon

“…The atmosphere for carbonization and activation is crucial in KOH‐activated carbon preparation. Nitrogen atmosphere is mostly reported 4, 7, 11, 12, 28, 49, 57, 69, 70, 173–175, 177, 183, 185–187, 190–197 and some researchers did not state the atmospheric condition under which their KOH‐activated carbons were prepared, e.g., Donnaperna et al. 19 Guizhen et al.…”

“…To fully comprehend the mechanism, thermodynamics, desorption studies, and spectroscopic analyses are also needed. As a re- Acetone removal 363-472 a) [190] Acid red 88 1486 a) [192] Supercapacitor material 449 c) and 92 b) [195] Supercapacitor material 297 c) [196] a) mg g -1 maximum sorption capacity, b) percent efficiency, n.a -not available, c) F g -1 specific capacitance, d) mmol g -1 sorption capacity sult, we accomplished our discussion on the adsorbate adsorption process using this entire body of research reports.…”

“…[4] Sewage sludge/corn straw 1 n.a 3:7:0-10 3 M HCl < 0.5 mm N 2 [7] Aerogel 3 n.a n.a n.a n.a N 2 [49] Kraft lignin KL 2 6.0-7.0 1:1-4 Hot distilled H 2 O n.a N 2 [57] Coconut leaves 1 7.0 1:1 3 M HCl 150-212 mm n.a [8] Peach stone 2 7.0 1:1, 3 0.1 M HCl n.a Steam/N 2 [10] Coconut carbon electrodes 1 n.a n.a 12 M HNO 3 n.a N 2 [69] Tobacco stem 1 6.5-7.0 n.a 0.1 mol HCl n.a N 2 [11] Tobacco stem 1.5 7.0 1:1 1 M HCl n.a N 2 [12] Polymer waste fullerene 1 n.a 1:1-5 0.5 N HCl n.a N 2 [70] Waste rubber tires 2 n.a 1:4 0.1 M HCl n.a N 2 [28] Thevetia peruviana shells 2 n.a 1:2 4 N HCl n.a N 2 [1] MWCNTs 2 n.a 1:5 Distilled H 2 O n.a n.a [19] n.a -not available. Corn cobs 1 6.0-7.0 1:0.5-4 0.1 mol HCl 0.18-0.42 mm N 2 [16] Rubber seed shells 2 7.0 150 g/500 mL n.a 1 mm N 2 [13] Lignin paper making black liquor 2.5 n.a 1:0.5-4 1 M HCl 420 mm N 2 [41] Gulfweed 3 7.0 3:4.5 0.1 M HCl n.a N 2 [9] MgO template porous carbon 3 n.a 1:1 n.a n.a N 2 [52] MWCNTs 2 n.a 1:6 1 M HCl n.a Ar [20] Coal 2 n.a 1:4 20 % HCl, 25 % HF n.a N 2 [71] Robusta coffee grounds 1 n.a 2:1 0.1 N HCl 300-500 mm N 2 /CO 2 [15] Walnut shell 1 n.a 1:2 n.a 0.5 mm N 2 [17] Olive cake 3 n.a 1:4 0.05 M HCl n.a n.a [75] Petroleum coke 1 n.a 1:2 10 % HCl n.a N 2 [44] Coffee shell n.a 6.0-7.0 1:1-5 0.1 M HCl 3 mm n.a [58] [190] Olive pomace 560, 700, 840 2 7 1:1, 1:2, 1:4 1 M HCl n.a N 2 [191] Pomelo peel 650-800 1.5 7 1:1-2.5:1 0.1 M HCl n.a N 2 [192] Garlic peel 400-700 2 7 4:1 0.1 M HCl n.a N 2 [193] Corn cob carbon 400 0.5 7 n.a 1 M HCl/absolute ethanol n.a N 2 [194] Coconut shell carbon 800 4 6-7 1:1-1:3 0.2 M HCl n.a N 2 [195] Agave tequilana plant 800 1 7 1:2-1:4 0.01 M HCl n.a N 2 [196] Castor shell 800 2 7 2 M:4 g 2 M HCl n.a N 2…”