Mesoporous activated carbon yielded from pre-leached cassava peels

Abstract The search for alternatives to fossil based commercial activated carbon (AC) continues to reveal new eco-friendly potential precursors, among which is agricultural waste. The key research aspect in all these endeavors is empirical ascertainment of the core properties of the resultant AC to suit a particular purpose. These properties include; yield, surface area, pore volume and the active surface groups. It is therefore pertinent to have process conditions controlled and tailored towards these properties for the required resultant AC. Highly porous AC was prepared from cassava peels by pre-treating and activating them using NaOH and KOH respectively. The carbonization temperatures were between 480 and 780°C in an activation-carbonization stepwise process using KOH as the activator at a KOH: peel ratio of 5:2 (mass basis). A 42% maximum yield of AC was realized along with a total pore volume of 0.756 cm3g− 1 and BET surface area of 1684 m2g− 1. The AC was dominantly microporous for carbonization temperatures below 780°C but a remarkable increase in mesopore volume (0.471 cm3g− 1) relative to the micropore volume (0.281 cm3g− 1) was observed at 780°C. The Fourier transform infra red (FTIR) spectroscopy for the pre-treated cassava peels showed distortion in the C-H bonding depicting possible elaboration of more lignin from cellulose disruption by NaOH. A carboxylate stretch was also observed owing to the reaction of Na+ ions with the carboxyl group in the raw peels. FTIR showed possible absorption bands for the AC between 1425 and 1712 cm− 1 wave numbers. Besides the botanical qualities of the cassava peel genotype used, pre-leaching the peels and also increasing holding activation temperature above the melting point of potassium enabled the modified process of producing highly porous AC from cassava peel. The SEM imaging showed well-developed hexagonal pores in the resultant AC.

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Mesoporous activated carbon yielded from pre-leached cassava peels

Bioresources and Bioprocessing ◽

10.1186/s40643-021-00407-0 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

R. Kayiwa ◽

H. Kasedde ◽

M. Lubwama ◽

J. B. Kirabira

Keyword(s):

Activated Carbon ◽

Electron Microscope ◽

Surface Area ◽

Pore Volume ◽

Process Conditions ◽

Koh Activation ◽

Absorption Bands ◽

Mesoporous Activated Carbon ◽

Cassava Peels ◽

Cassava Peel

AbstractThe search for alternatives to fossil-based commercial activated carbon (AC) continues to reveal new eco-friendly potential precursors, among which is agricultural waste. The key research aspect in all these endeavors is empirical ascertainment of the core properties of the resultant AC to suit a particular purpose. These properties include: yield, surface area, pore volume, and the active surface groups. It is therefore pertinent to have process conditions controlled and tailored towards these properties for the required resultant AC. Pre-leaching cassava peels with NaOH followed by KOH activation and carbonization at holding temperatures (780 °C) above the melting point of K (760 °C) yielded mesoporous activated carbon with the highest surface area ever reported for cassava peel-based AC. The carbonization temperatures were between 480 and 780 °C in an activation–carbonization stepwise process using KOH as the activator at a KOH:peel ratio of 5:2 (mass basis). A 42% maximum yield of AC was realized along with a total pore volume of 0.756 cm3g−1 and BET surface area of 1684 m2g−1. The AC was dominantly microporous for carbonization temperatures below 780 °C, but a remarkable increase in mesopore volume (0.471 cm3g−1) relative to the micropore volume (0.281 cm3g−1) was observed at 780 °C. The Fourier transform infrared (FTIR) spectroscopy for the pre-treated cassava peels showed distortion in the C–H bonding depicting possible elaboration of more lignin from cellulose disruption by NaOH. A carboxylate stretch was also observed owing to the reaction of Na+ ions with the carboxyl group in the raw peels. FTIR showed possible absorption bands for the AC between 1425 and 1712 cm−1 wave numbers. Besides the botanical qualities of the cassava peel genotype used, pre-leaching the peels and also increasing holding activation temperature above the boiling point of potassium enabled the modified process of producing highly porous AC from cassava peel. The scanning electron microscope (SEM) and transmission electron microscope (TEM) imaging showed well-developed hexagonal pores in the resultant AC and intercalated K profile in the carbon matrices, respectively.

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Carbonization Temperature Effect over Activated Carbon Porosity Derived from Industrial Processing Waste

Academic Perspective Procedia ◽

10.33793/acperpro.02.03.133 ◽

2019 ◽

Vol 2 (3) ◽

pp. 1205-1209

Author(s):

Hasan Sayğılı

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Pore Volume ◽

Activated Carbons ◽

Waste Product ◽

Total Pore Volume ◽

Carbonization Temperature ◽

Bet Surface Area ◽

Processing Waste ◽

Industrial Processing

The influence of carbonization temperature (CT) on pore properties of the prepared activated carbon using lentil processing waste product (LWP) impregnated with potassium carbonate was studied. Activated carbons (ACs) were obtained by impregnation with 3:1 ratio (w/w) K2CO3/LWP under different carbonization temperatures at 600, 700, 800 and 900 oC for 1h. Activation at low temperature represented that micropores were developed first and then mesoporosity developed, enhanced up to 800 oC and then started to decrease due to possible shrinking of pores. The optimum temperature for LWP was found to be around 800 oC on the basis of total pore volume and the Brunauer-Emmett-Teller (BET) surface area. The optimum LWPAC sample was found with a CT of 800 oC, which gives the highest BET surface area and pore volume of 1875 m2/g and 0.995 cm3/g, respectively.

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Porous Lactose as a Novel Ingredient Carrier for the Improvement of Quercetin Solubility In Vitro

Bioinorganic Chemistry and Applications ◽

10.1155/2021/2586990 ◽

2021 ◽

Vol 2021 ◽

pp. 1-6

Author(s):

Wen Liu ◽

Tong-Tong Wang ◽

Xiao-Luan Tang ◽

Fei-Ya Jiang ◽

Xiao Yan ◽

...

Keyword(s):

Surface Area ◽

Pore Volume ◽

Reduction Rate ◽

Xrd Analysis ◽

Bet Surface Area ◽

Pore Width ◽

Release Rates ◽

Loading Efficiency ◽

Highly Porous

In this work, quercetin was loaded in the highly-porous lactose via the adsorption of quercetin molecules in ethanol. The method aims to improve the quercetin solubility and the loading capacity of lactose. The method relates to the synthesis of the highly-porous lactose with a particle size of ∼35 μm, a mean pore width of ∼30 nm, a BET surface area of 35.0561 ± 0.4613 m2/g, and a BJH pore volume of ∼0.075346 cc/g. After the quercetin loading in ethanol, BET surface area and BJH pore volume of porous lactose were reduced to 28.8735 ± 0.3526 m2/g and 0.073315 cc/g, respectively. The reduction rate was based on the quercetin loading efficiency of highly-porous lactose. DSC analysis and XRD analysis suggest that the sediments of quercetin in the nanopores of porous lactose are crystalline. FTIR spectroscopy results suggest that there is no significant interaction between quercetin and lactose. The highly-porous lactose had a higher loading efficiency of 20.3% (w/w) compared to the α-lactose (with 5.2% w/w). The release rates of quercetin from the highly-porous lactose tablets were faster compared to the conventional α-lactose carrier.

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Experimental Research on the Preparation of Porous Activated Carbon from Orange Wastes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.1907 ◽

2009 ◽

Vol 79-82 ◽

pp. 1907-1910

Author(s):

Zhi Gang Xie

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Pore Volume ◽

Pore Diameter ◽

Total Pore Volume ◽

Carbonization Temperature ◽

Bet Surface Area ◽

Average Pore ◽

Impregnation Ratio ◽

Heat Preservation

Porous activated carbon was prepared from orange wastes using zinc chloride as an activating agent by one-step carbonization method. Effects of impregnation ratio, carbonization temperature and heat preservation time on pore characteristics of activated carbon were studied. The porous structures of the orange wastes activated carbon were investigated by BET, D-R equations, BJH equations and Kelvin theory. The morphology was observed using transmission electron microscopy (TEM). The mesoporous activated carbon is gained when the impregnation ratio is 3:1; the carbonization temperature is 550°Cand heat preservation time is 1.0 h. The activated carbon has total pore volume 2.098 cm3/g, mesoporous pore volume 1.438 cm3/g, with a high BET surface area 1476m2/g. The pore distribution of the mesoporous activated carbon is very concentrative, with average pore diameter of 3.88nm. While, the high specific surface area activated carbon is gained when the impregnation ratio is 2:1; the carbonization temperature is 550°Cand heat preservation time is 1.0 h. The activated carbon has high BET surface area 1909 m2/g, while the total pore volume is only 1.448cm3/g and microporous pore volume is 0.889cm3/g, with average pore diameter of 2.29 nm.

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Ferromagnetic activated carbon from cassava (Manihot dulcis) peels activated by iron(III) chloride: Synthesis and characterization

BioResources ◽

10.15376/biores.15.2.2133-2146 ◽

2020 ◽

Vol 15 (2) ◽

pp. 2133-2146

Author(s):

Gervais Kounou Ndongo ◽

Ndi Julius Nsami ◽

Ketcha Joseph Mbadcam

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Total Pore Volume ◽

Volatile Matter ◽

Proximate Analysis ◽

Sem Analysis ◽

Raw Material ◽

Bet Surface Area ◽

X Ray ◽

Cassava Peel

Ferromagnetic activated carbon (FAC) was prepared through impregnation of cassava peel with FeCl3 (3.75%) solution and pyrolyzed at 800 °C. Samples were characterized using iodine number, methylene blue number, X-ray fluorescence, Fourier transformation infrared, X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled to energy dispersive X-ray spectroscopy, elemental analysis and N2 adsorption for surface area determination. The proximate analysis of cassava peel showed that the moisture content, fixed carbon, ash content, and the volatile matter were 3.52%, 82.97%, 4.97%, and 8.54%, respectively. The prepared FAC had a BET surface area of 405.9 m2/g, pore size of 2.03 nm and total pore volume of 0.11 cm3/g. The SEM analysis showed the presence of both micro and mesopores on the FAC sample. The XRD pattern of FAC showed the presence of characteristic peaks of magnetite–maghemite, confirming that the prepared material is ferromagnetic. According to the experimental results, the cassava peels are considered as appropriate raw material for FAC preparation.

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A Preliminary Study on the Preparation of Activated Carbon from Cyrtosperma chamissonis Petioles via Single Step H3PO4 Activation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.799-800.47 ◽

2015 ◽

Vol 799-800 ◽

pp. 47-51

Author(s):

M.S. Mohammed Yahya ◽

Jeyashelly Andas ◽

Ghani Zaidi Ab

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Activated Carbons ◽

Value Added ◽

Single Step ◽

Bet Surface Area ◽

Impregnation Temperature ◽

Preliminary Study ◽

Adsorption Desorption ◽

Highly Porous

In this study, highly porous activated carbon was prepared fromCyrtospermachamissonispetioles via single step H3PO4activation. The effect of impregnation temperature (RT – 90 °C) on the yield, porosity and surface area was investigated. The synthesized activated carbons were characterized by Na2S2O3volumetric method, SEM/EDX and N2adsorption-desorption analyses. The optimization investigation clearly showed that the impregnation temperature affected on the yield and the specific surface area of the materials. Under the optimum impregnation temperature of 75 °C, the registered iodine number and BET surface area were 1129.23 mgg-1and 1390.41 m2g-1respectively with yield percentage of 35.82. This preliminary study proves the successful conversion of plant waste into value added porous materials.

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Effect of textural and chemical characteristics of activated carbons on phenol adsorption in aqueous solutions

Polish Journal of Chemical Technology ◽

10.1515/pjct-2017-0072 ◽

2017 ◽

Vol 19 (4) ◽

pp. 87-93 ◽

Cited By ~ 2

Author(s):

Diana P. Vargas ◽

Liliana Giraldo ◽

Juan Carlos Moreno-Piraján

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Surface Area ◽

Pore Volume ◽

Activated Carbons ◽

Chemical Activation ◽

Chemical Properties ◽

Granular Activated Carbon ◽

Bet Surface Area ◽

Phenol Adsorption

Abstract The effect of textural and chemical properties such as: surface area, pore volume and chemical groups content of the granular activated carbon and monoliths on phenol adsorption in aqueous solutions was studied. Granular activated carbon and monolith samples were produced by chemical activation. They were characterized by using N2 adsorption at 77 K, CO2 adsorption at 273 K, Boehm Titrations and immersion calorimetry in phenol solutions. Microporous materials with different pore size distribution, surface area between 516 and 1685 m2 g−1 and pore volumes between 0.24 and 0.58 cm3 g−1 were obtained. Phenol adsorption capacity of the activated carbon materials increased with increasing BET surface area and pore volume, and is favored by their surface functional groups that act as electron donors. Phenol adsorption capacities are in ranged between 73.5 and 389.4 mg · g−1.

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Preparation and characterization of activated carbons from different kinds of coal

Proceedings of the Mongolian Academy of Sciences ◽

10.5564/pmas.v60i3.1422 ◽

2020 ◽

pp. 25-31

Author(s):

Batkhishig Damdin ◽

Purevsuren Barnasan ◽

Chung-Jun Lin ◽

Batbileg Sanjaa ◽

Ariunaa Alyeksandr

Keyword(s):

Methylene Blue ◽

Activated Carbon ◽

Iodine Number ◽

Surface Area ◽

Pore Volume ◽

Activated Carbons ◽

Bet Surface Area ◽

Water Steam ◽

Initial Coal

Initial coal was purified in heavy liquid with a density 1.3 cm3 of ZnCl2 solution and purified coal was carbonized and the initial coal samples of each deposits were purified by pyrolysis. Thus, the yield of pyrolysis hard residue in the enriched sample was slightly higher than in the hard residue of initial coal. Therefore, pyrolysis hard residue of purified coal (carbonized sample) was activated at 800°C for 2 hours by preheated water steam. Activated carbons (ACs) and non-activated and non-carbonized coal from Baganuur, Ereen and Nariin Sukhait deposits were technically analyzed and their iodine number, BET surface area, pore volume and adsorption of methylene blue (MB) were determined. When these results were compared, these indicators increased 5-17 times in the Baganuur activated carbon (BN-AC), Ereen activated carbon (E-AC) and Nariin Sukhait activated carbon (NS-AC) as compared to inactivated coal.

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Properties of activated carbon regulated by rapid cooling treatment after pyrolysis

BioResources ◽

10.15376/biores.14.4.7935-7942 ◽

2019 ◽

Vol 14 (4) ◽

pp. 7935-7942

Author(s):

Bing Wang ◽

Huiyuan Chen ◽

Yonggang Li ◽

Hongyu Si ◽

Haomin Wei ◽

...

Keyword(s):

Activated Carbon ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Activated Carbons ◽

Raw Materials ◽

Average Pore Size ◽

Process Conditions ◽

Rapid Cooling

Effects of rapid cooling following pyrolysis were studied relative to the properties of activated carbon using different biomass as the raw materials. Coconut shell-based activated carbon (CSAC), bamboo-based activated carbon (BAC), and straw-based activated carbon (WSAC) were activated via high temperature and subsequently rapidly cooled to below minus 150 °C. The results showed that rapid cooling effectively increased the specific surface area, pore volume, and yield of activated carbons. Compared to natural cooling, rapid cooling increased the specific surface area of CSAC from 1076 m2/g to 1484 m2/g, increased the pore volume from 1.46 mL/g to 1.57 mL/g, decreased the average pore size from 2.25 nm to 2.13 nm, and increased the yield from 27.1% to 31.5%. The variation of the properties of activated carbon after rapid cooling using different raw materials and process conditions were studied using orthogonal experiments.

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Effect of Formaldehyde to Phenol Ratio in Phenolic Beads on Pore Structure, Adsorption and Mechanical Properties of Activated Carbon Spheres

Defence Science Journal ◽

10.14429/dsj.69.12821 ◽

2019 ◽

Vol 69 (1) ◽

pp. 46-52 ◽

Cited By ~ 2

Author(s):

Arjun Singh ◽

Sanjeevan Aggrawal ◽

Darshan Lal

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Activated Carbon ◽

Pore Structure ◽

Surface Area ◽

Pore Volume ◽

Bet Surface Area ◽

Activation Process ◽

Carbon Spheres ◽

Activated Carbon Spheres

Phenolic beads (PBs) prepared from different formaldehyde to phenol (F/P) molar ratios were used as polymeric precursor for activated carbon. Activated carbon spheres (ACSs) have been produced from PBs via the physical activation process using carbon dioxide (CO2) as activating agent at 950 °C for different burn-off. The prepared ACSs were investigated for nitrogen adsorption, surface morphology and compressive strength by means of BET surface area analyser, scanning electron microscopy (SEM) and carbon and sphere tester techniques. The results indicated that the effects of F/P ratio observed, especially variation in the adsorption and mechanical properties. It was found that ACSs obtained from F/P ratio one showed the superior adsorption properties, possessed a high BET surface area in a range of 836 m2 g-1 to 3694 m2 g-1 with high pore volume (0.47 cm3 g-1 - 2.47 cm3 g-1) and 73-97 per cent microporosity. The BET surface area and pore volume increased, while the microporosity gradually decreased, with increasing the extent of burn-off. Compressive strength decreased with increasing F/P ratio as well as the extent of burn-off. ACSs upheld improved compressive strength (from 160 N mm-2 to 9 N mm-2) than those obtained from F/P ratio 2 and 3 in PBs. SEM studies of ACSs demonstrated well developed pore structure.

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