Modification of the adsorption properties of high surface area graphites by oxygen functional groups

The adsorption properties of two nanomorphologies of trititanate, nanotubes (TiNT) and plates (TiNP), prepared by the hydrothermal reaction of concentrated NaOH with different phases of TiO2, were examined. It was found that the capacity for both morphologies towards methylene blue (MB), an ideal pollutant, was extremely high, with the TiNP having a capacity of 130 mg/g, higher than the TiNT, whose capacity was 120 mg/g at 10 mg/L MB concentration. At capacity, the well-dispersed powders deposit on the floor of the reaction vessel. The two morphologies had very different structural and adsorption properties. TiNT with high surface area and pore volume exhibited exothermic monolayer adsorption of MB. TiNP with low surface area and pore volume yielded a higher adsorption capacity through endothermic multilayer adsorption governed by pore diffusion. TiNP exhibited a higher negative surface charge of −23 mV, compared to −12 mV for TiNT. The adsorption process appears to be an electrostatic interaction, with the cationic dye attracted more strongly to the nanoplates, resulting in a higher adsorption capacity and different adsorption modes. We believe this simple, low cost production of high capacity nanostructured adsorbent material has potential uses in wastewater treatment.

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Rice Husk-Derived High Surface Area Nanoporous Carbon Materials with Excellent Iodine and Methylene Blue Adsorption Properties

C – Journal of Carbon Research ◽

10.3390/c5010010 ◽

2019 ◽

Vol 5 (1) ◽

pp. 10 ◽

Cited By ~ 10

Author(s):

Lok Shrestha ◽

Mamata Thapa ◽

Rekha Shrestha ◽

Subrata Maji ◽

Raja Pradhananga ◽

...

Keyword(s):

Methylene Blue ◽

Surface Area ◽

Rice Husk ◽

Carbon Materials ◽

High Surface ◽

High Surface Area ◽

Nanoporous Carbon ◽

Adsorption Properties ◽

Methylene Blue Adsorption ◽

Nanoporous Carbon Materials

Iodine and methylene blue adsorption properties of the high surface area nanoporous carbon materials derived from agro-waste and rice husk is reported. Rice husk was pre-carbonized at 300 °C in air followed by leaching out the silica nanoparticles by extraction with sodium hydroxide solution. The silica-free rice husk char was mixed with chemical activating agents sodium hydroxide (NaOH), zinc chloride (ZnCl2), and potassium hydroxide (KOH) separately at a mixing ratio of 1:1 (wt%) and carbonized at 900 °C under a constant flow of nitrogen. The prepared carbon materials were characterized by scanning electron microscopy (SEM), Fourier transformed-infrared spectroscopy (FT-IR), powder X-ray diffraction (pXRD), and Raman scattering. Due to the presence of bimodal micro- and mesopore structures, KOH activated samples showed high specific surface area ca. 2342 m2/g and large pore volume ca. 2.94 cm3/g. Oxygenated surface functional groups (hydroxyl, carbonyl, and carboxyl) were commonly observed in all of the samples and were essentially non-crystalline porous particle size of different sizes (<200 μm). Adsorption study revealed that KOH activated samples could be excellent material for the iodine and methylene blue adsorption from aqueous phase. Iodine and methylene blue number were ca. 1726 mg/g and 608 mg/g, respectively. The observed excellent iodine and methylene blue adsorption properties can be attributed to the well-developed micro- and mesopore structure in the carbon material. This study demonstrates that the agricultural waste, rice husk, and derived nanoporous carbon materials would be excellent adsorbent materials in water purifications.

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Hierarchical flowerlike magnesium oxide hollow spheres with extremely high surface area for adsorption and catalysis

Journal of Materials Chemistry A ◽

10.1039/c5ta08542j ◽

2016 ◽

Vol 4 (2) ◽

pp. 400-406 ◽

Cited By ~ 55

Author(s):

Shuliang Yang ◽

Peipei Huang ◽

Li Peng ◽

Changyan Cao ◽

Yanan Zhu ◽

...

Keyword(s):

Heavy Metal ◽

Surface Area ◽

Magnesium Oxide ◽

Heavy Metal Ions ◽

Catalytic Properties ◽

Condensation Reaction ◽

High Surface ◽

Hollow Spheres ◽

High Surface Area ◽

Adsorption Properties

3D hierarchical flowerlike MgO hollow spheres with extremely high surface area showed excellent adsorption properties for heavy metal ions and catalytic properties for the Claisen–Schmidt condensation reaction.

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Ultra-high adsorption of tetracycline antibiotics on garlic skin-derived porous biomass carbon with high surface area

New Journal of Chemistry ◽

10.1039/c9nj05396d ◽

2020 ◽

Vol 44 (3) ◽

pp. 1097-1106 ◽

Cited By ~ 8

Author(s):

Shujian Liu ◽

Mingdi Pan ◽

Zhongmin Feng ◽

Yangchun Qin ◽

Yun Wang ◽

...

Keyword(s):

Surface Area ◽

High Surface ◽

High Surface Area ◽

Water Environment ◽

High Specific Surface Area ◽

Adsorption Properties ◽

Porous Carbon Material ◽

Biomass Carbon ◽

High Adsorption ◽

Tetracycline Antibiotics

A porous carbon material with ultra-high specific surface area was prepared from waste garlic skin, and exhibited excellent adsorption properties to TCs in a water environment.

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Preparation and Adsorption Properties of Corncob-Derived Activated Carbon with High Surface Area

Journal of Chemical & Engineering Data ◽

10.1021/je1002913 ◽

2010 ◽

Vol 55 (11) ◽

pp. 4669-4676 ◽

Cited By ~ 26

Author(s):

Y. X. Wang ◽

B. S. Liu ◽

C. Zheng

Keyword(s):

Activated Carbon ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Adsorption Properties

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Preparation of Ammonia Dealuminated Metakaolinite and Its Adsorption against Bixin

Indonesian Journal of Chemistry ◽

10.22146/ijc.44706 ◽

2020 ◽

Vol 20 (4) ◽

pp. 791

Author(s):

Winda Rahmalia ◽

Jean-Francois Fabre ◽

Thamrin Usman ◽

Zéphirin Mouloungui

Keyword(s):

Surface Area ◽

Room Temperature ◽

High Surface ◽

High Surface Area ◽

Total Pore Volume ◽

Adsorption Properties ◽

Order Kinetic ◽

X Ray Diffraction ◽

X Ray ◽

Pseudo Second Order

This study aims to prepare dealuminated metakaolinite which has a high surface area by using NH4OH as an activator. The natural kaolinite sample was treated at 600 °C for 6 h in order to obtain metakaolinite. A dealuminated metakaolinite was then prepared by the repeated activation method using concentrated ammonia (5 M NH4OH) at room temperature. Depending on the nature of each type of material, natural kaolinite, NH4OH treated kaolinite, metakaolinite and NH4OH treated metakaolinite were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET-N2) measurements. XRD and FTIR results confirmed that structural transformation from kaolinite to metakaolinite had occurred. According to SEM-EDS data, the activation of metakaolinite by NH4OH allowed the dealumination of metakaolinite. The increase in the Si/Al ratio was almost twice as high as in kaolinite. BET-N2 analysis showed that the specific surface area and the total pore volume increased significantly after activation. Its adsorption properties were tested against bixin. Bixin adsorption on dealuminated metakaolinite followed pseudo-second order kinetic where k2 = 0.20 g/mg min. The adsorption isotherm followed the Langmuir model where qm = 0.72 mg/g.

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Preparation of high surface area mesoporous activated carbon fiber and its adsorption properties of sulfides from light oil

Nanoporous Materials IV, Proceedings of the 4th International Symposium on Nanoporous Materials - Studies in Surface Science and Catalysis ◽

10.1016/s0167-2991(05)80308-8 ◽

2005 ◽

pp. 951-956 ◽

Cited By ~ 3

Author(s):

W.Z. Shen ◽

J.T. Zheng ◽

Q.J. Guo

Keyword(s):

Activated Carbon ◽

Carbon Fiber ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Adsorption Properties ◽

Activated Carbon Fiber ◽

Mesoporous Activated Carbon ◽

Light Oil

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COVID-19 Prevention: Role of Activated Carbon

Journal of Engineering and Technological Sciences ◽

10.5614/j.eng.technol.sci.2021.53.4.4 ◽

2021 ◽

Vol 53 (4) ◽

pp. 210404

Author(s):

Md Sumon Reza ◽

ABM Kamrul Hasan ◽

Abu Saleh Ahmed ◽

Shammya Afroze ◽

Muhammad Saifullah Abu Bakar ◽

...

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Functional Groups ◽

Human Body ◽

High Surface ◽

High Surface Area ◽

Preliminary Stage ◽

Novel Virus

Recently, Coronavirus Disease 2019 (COVID-19) has brought the whole world into a pandemic condition, where the number of infected cases and deaths is exponentially high. A number of vaccines are available for this novel virus, but these are in the preliminary stage and are also not available to everyone. As the virus is very contagious, protection and prevention are the best way to survive and get rid of this disease. The virus affects the human body by entering through the nose, mouth, and eyes, so face protection with an appropriate mask is highly advisable. Combined masks made with activated carbon (AC) can effectively adsorb the virus because of its high surface area and broad functional groups. Such combined masks can also control coronavirus transmission by capturing harmful gases and smoke as they help in decreasing the spread of the virus

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Tenacious Mass Transfer Limitations Drive Catalytic Selectivity during Electrochemical Carbon Dioxide Reduction

10.26434/chemrxiv.7770338.v1 ◽

2019 ◽

Cited By ~ 1

Author(s):

Kailun Yang ◽

Recep Kas ◽

Wilson A. Smith

Keyword(s):

Surface Area ◽

High Surface ◽

High Surface Area ◽

Catalyst Layer ◽

Active Surface ◽

Active Surface Area ◽

High Concentration ◽

Copper Electrodes ◽

Surface Enhanced ◽

Local Current

This study evaluated the performance of the commonly used strong buffer electrolytes, i.e. phosphate buffers, during CO2 electroreduction in neutral pH conditions by using in-situ surface enhanced infrared absorption spectroscopy (SEIRAS). Unfortunately, the buffers break down a lot faster than anticipated which has serious implications on many studies in the literature such as selectivity and kinetic analysis of the electrocatalysts. Increasing electrolyte concentration, surprisingly, did not extend the potential window of the phosphate buffers due to dramatic increase in hydrogen evolution reaction. Even high concentration phosphate buffers (1 M) break down within the potentials (-1 V vs RHE) where hydrocarbons are formed on copper electrodes. We have extended the discussion to high surface area electrodes by evaluating electrodes composed of copper nanowires. We would like highlight that it is not possible to cope with high local current densities on these high surface area electrodes by using high buffer capacity solutions and the CO2 electrocatalysts are needed to be evaluated by casting thin nanoparticle films onto inert substrates as commonly employed in fuel cell reactions and up to now scarcely employed in CO2 electroreduction. In addition, we underscore that normalization of the electrocatalytic activity to the electrochemical active surface area is not the ultimate solution due to concentration gradient along the catalyst layer.This will “underestimate” the activity of high surface electrocatalyst and the degree of underestimation will depend on the thickness, porosity and morphology of the catalyst layer.

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