Characterization of Low-Pressure Nitrogen Plasma Discharge and Pre-Oxidation on the Surface Characteristics of Activated Carbons

2020 ◽  
Vol 998 ◽  
pp. 102-107
Author(s):  
Ria Grace Abdon ◽  
Top Archie Dela Peña ◽  
Camille Punongbayan ◽  
John Achilles Ricafrente
Keyword(s):  
Activated Carbon ◽  
Surface Morphology ◽  
Surface Area ◽  
Functional Groups ◽  
Activated Carbons ◽  
Low Pressure ◽  
Plasma Discharge ◽  
Total Surface Area ◽  
Micropore Volume ◽  
Nitrogen Plasma

Commercial activated carbon (CAC) was modified using low-pressure radio frequency nitrogen plasma discharge (NPD) operating at 0.3 mbar and 40 kHz. The surface chemistry of CAC was modified using HNO3 pre-oxidation to possibly influence the reactivity of NPD. The results of x-ray photoelectron spectroscopy (XPS) suggested that pre-oxidation reduces aromaticity, generates aliphatic carbons (C-C and C-H), and increases carboxylic functional groups (COOH) which probably enhances the nitrogen plasma functionalization based on the N/C ratio for CAC-O-P (4.29 %) compared to CAC-P (2.88 %). FTIR was used to confirm such effects of pre-oxidation from the functional groups present on the carbon surface. The total surface area was identified using Langmuir and Brunauer–Emmett–Teller (BET) N2 adsorption isotherms at 77 K. Both pre-oxidation and plasma treatment caused an increase in the surface area of CAC up to 150 percent. Carbon t-plot method was used to determine the micropore volume, micropore area, and external surface area. The total surface area of each activated carbon was mostly constituted of micropore area which was identified to be directly proportional to the micropore volume. Scanning electron microscope (SEM) confirms the destruction of the surface morphology for CAC-O that might have caused the increase in surface area. Development of surface threadlike structures were observed for the NPD treated CAC-O. NPD favors the development of NH2 functionalities and reduces the aromaticity of activated carbons while enhancing the surface morphology and the surface area.

scholarly journals Surface Modification and Characterization of Coconut Shell-Based Activated Carbon Subjected to Acidic and Alkaline Treatments

2017 ◽  
Vol 4 (2) ◽  
pp. 186-194 ◽  
Author(s):  
Tan I. A. W. ◽  
Abdullah M. O. ◽  
Lim L. L. P. ◽  
Yeo T. H. C.
Keyword(s):  
Activated Carbon ◽  
Surface Morphology ◽  
Surface Chemistry ◽  
Pore Structure ◽  
Surface Area ◽  
Functional Groups ◽  
Activated Carbons ◽  
Coconut Shell ◽  
Bet Surface Area ◽  
Textural Characterization

Activated carbon derived from agricultural biomass has been increasingly recognized as a multifunctional material for various applications according to its physicochemical characteristics. The application of activated carbon in adsorption process mainly depends on the surface chemistry and pore structure which is greatly influenced by the treatment method. This study aims to compare the textural characteristics, surface chemistry and surface morphology of coconut shell-based activated carbon modified using chemical surface treatments with hydrochloric acid (HCl) and sodium hydroxide (NaOH). The untreated and treated activated carbons were characterized for their physical and chemical properties including the Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and textural characterization. The FTIR spectra displayed bands confirming the presence of carboxyl, hydroxyl and carbonyl functional groups. The Brunauer–Emmett–Teller (BET) surface area of the untreated activated carbon was 436 m2/g whereas the surface area of the activated carbon modified using 1M NaOH, 1M HCl and 2M HCl was 346, 525 and 372 m2/g, respectively. SEM micrographs showed that many large pores in a honeycomb shape were clearly found on the surface of 1M HCl sample. The pore structure of the activated carbon treated with 2M HCl and NaOH was partially destroyed or enlarged, which decreased the BET surface area. The modification of the coconut shell-based activated carbon with acidic and alkaline treatments has successfully altered the surface functional groups, surface morphology and textural properties of the activated carbon which could improve its adsorptive selectivity on a certain adsorbate.

scholarly journals Coffee residue-based activated carbons for phenol removal

2021 ◽  
Author(s):  
Hemavathy Palanisami ◽  
Mohamad Rafiuddin Mohd Azmi ◽  
Muhammad Abbas Ahmad Zaini ◽  
Zainul Akmar Zakaria ◽  
Muhd Nazrul Hisham Zainal Alam ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Functional Groups ◽  
High Performance ◽  
Activated Carbons ◽  
Phenol Removal ◽  
Surface Functional Groups ◽  
Maximum Capacity ◽  
Second Stage ◽  
Adsorptive Properties

Abstract This work was aimed to evaluate the adsorptive properties of activated carbons from coffee residue for phenol removal. The coffee residue was activated using H3PO4 and KOH, and the resultant activated carbons were characterized for surface area and functional groups. The values of surface area were recorded as 1,030 m2/g and 399 m2/g for H3PO4- and KOH-activated carbons, respectively. The maximum capacity for phenol removal is comparable for both activated carbons at 43 mg/g. The pores might be inaccessible due to electrostatic repulsion by surface functional groups and hydroxyl anions. The second stage in a two-stage adsorber design is necessary to accomplish the process with high performance and minimum dosage of activated carbon. Coffee residue is a promising activated carbon precursor for phenol removal.

Increase the Microporosity and CO2 Adsorption of a Commercial Activated Carbon

2015 ◽  
Vol 749 ◽  
pp. 17-21 ◽  
Author(s):  
Joanna Sreńscek Nazzal ◽  
Karolina Glonek ◽  
Jacek Młodzik ◽  
Urszula Narkiewicz ◽  
Antoni W. Morawski ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Carbon Materials ◽  
Micropore Volume ◽  
Microporous Carbon ◽  
Microporous Carbons ◽  
Adsorption Capacities

Microporous carbons prepared from commercial activated carbon WG12 by KOH and/or ZnCl2 treatment were examined as adsorbents for CO2 capture. The micropore volume and specific surface area of the resulting carbons varied from 0.52 cm3/g (1374 m2/g) to 0.70 cm3/g (1800 m2/g), respectively. The obtained microporous carbon materials showed high CO2 adsorption capacities at 40 bar pressure reaching 16.4 mmol/g.

The influential factors towards graphene oxides removal by activated carbons: Activated functional groups vs BET surface area

2018 ◽  
Vol 271 ◽  
pp. 142-150 ◽  
Author(s):  
Ju Sun ◽  
Xia Liu ◽  
Shengxia Duan ◽  
Ahmed Alsaedi ◽  
Fengsong Zhang ◽  
...  
Keyword(s):  
Surface Area ◽  
Functional Groups ◽  
Activated Carbons ◽  
Influential Factors ◽  
Bet Surface Area ◽  
Graphene Oxides

scholarly journals Optimisation of durian peel based activated carbon preparation conditions for dye removal

2013 ◽  
Vol 16 (1) ◽  
pp. 22-31
Author(s):  
Phung Thi Kim Le ◽  
Kien Anh Le
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Surface Area ◽  
Dye Removal ◽  
Activated Carbons ◽  
Low Cost ◽  
Waste Water Treatment ◽  
Impregnation Ratio ◽  
Carbon Production ◽  
Removal Capacity

Agricultural wastes are considered to be a very important feedstock for activated carbon production as they are renewable sources and low cost materials. This study present the optimize conditions for preparation of durian peel activated carbon (DPAC) for removal of methylene blue (MB) from synthetic effluents. The effects of carbonization temperature (from 673K to 923K) and impregnation ratio (from 0.2 to 1.0) with potassium hydroxide KOH on the yield, surface area and the dye adsorbed capacity of the activated carbons were investigated. The dye removal capacity was evaluated with methylene blue. In comparison with the commercial grade carbons, the activated carbons from durian peel showed considerably higher surface area especially in the suitable temperate and impregnation ratio of activated carbon production. Methylene blue removal capacity appeared to be comparable to commercial products; it shows the potential of durian peel as a biomass source to produce adsorbents for waste water treatment and other application. Optimize condition for preparation of DPAC determined by using response surface methodology was at temperature 760 K and IR 1.0 which resulted the yield (51%), surface area (786 m2/g), and MB removal (172 mg/g).

scholarly journals Preparation and characterization of activated carbons from albizia saman pod

2017 ◽  
Vol 36 (3) ◽  
pp. 44-53
Author(s):  
G. D. Akpen ◽  
M. I. Aho ◽  
N. Baba
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Activated Carbons ◽  
High Surface ◽  
High Surface Area ◽  
Volatile Matter ◽  
Sieve Analysis ◽  
Albizia Saman ◽  
Temperature Surface

Activated carbon was prepared from the pods of Albizia saman for the purpose of converting the waste to wealth. The pods were thoroughly washed with water to remove any dirt, air- dried and cut into sizes of 2-4 cm. The prepared pods were then carbonised in a muffle furnace at temperatures of 4000C, 5000C, 6000C ,7000C and 8000C for 30 minutes. The same procedure was repeated for 60, 90, 120 and 150 minutes respectively. Activation was done using impregnationratios of 1:12, 1:6, 1:4, 1:3, and 1:2 respectively of ZnCl2 to carbonised Albizia saman pods by weight. The activated carbon was then dried in an oven at 1050C before crushing for sieve analysis. The following properties of the produced Albizia saman pod activated carbon (ASPAC) were determined: bulk density, carbon yield, surface area and ash, volatile matter and moisture contents. The highest surface area of 1479.29 m2/g was obtained at the optimum impregnation ratio, carbonization time and temperature of 1:6, 60 minutes and 5000C respectively. It was recommended that activated carbon should be prepared from Albizia saman pod with high potential for adsorption of pollutants given the high surface area obtained.Keywords: Albizia saman pod, activated carbon, carbonization, temperature, surface area

scholarly journals Pinecone-Derived Activated Carbons as an Effective Medium for Hydrogen Storage

Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2237
Author(s):  
Sara Stelitano ◽  
Giuseppe Conte ◽  
Alfonso Policicchio ◽  
Alfredo Aloise ◽  
Giovanni Desiderio ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Hydrogen Storage ◽  
Adsorption Capacity ◽  
Surface Area ◽  
Hydrogen Adsorption ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Textural Properties ◽  
Biomass Waste ◽  
Wavelength Dispersive Spectrometry

Pinecones, a common biomass waste, has an interesting composition in terms of cellulose and lignine content that makes them excellent precursors in various activated carbon production processes. The synthesized, nanostructured, activated carbon materials show textural properties, a high specific surface area, and a large volume of micropores, which are all features that make them suitable for various applications ranging from the purification of water to energy storage. Amongst them, a very interesting application is hydrogen storage. For this purpose, activated carbon from pinecones were prepared using chemical activation with different KOH/precursor ratios, and their hydrogen adsorption capacity was evaluated at liquid nitrogen temperatures (77 K) at pressures of up to 80 bar using a Sievert’s type volumetric apparatus. Regarding the comprehensive characterization of the samples’ textural properties, the measurement of the surface area was carried out using the Brunauer–Emmett–Teller method, the chemical composition was investigated using wavelength-dispersive spectrometry, and the topography and long-range order was estimated using scanning electron microscopy and X-ray diffraction, respectively. The hydrogen adsorption properties of the activated carbon samples were measured and then fitted using the Langmuir/ Töth isotherm model to estimate the adsorption capacity at higher pressures. The results showed that chemical activation induced the formation of an optimal pore size distribution for hydrogen adsorption centered at about 0.5 nm and the proportion of micropore volume was higher than 50%, which resulted in an adsorption capacity of 5.5 wt% at 77 K and 80 bar; this was an increase of as much as 150% relative to the one predicted by the Chahine rule.

scholarly journals Synthesis of activated carbon doped with transition metals for hydrogen storage

2019 ◽  
Vol 90 ◽  
pp. 01016 ◽  
Author(s):  
Nazlina Ya’aini ◽  
Arjun Pillay A/L Gopala Krishnan ◽  
Adnan Ripin
Keyword(s):  
Activated Carbon ◽  
Transition Metals ◽  
Surface Area ◽  
Hydrogen Adsorption ◽  
Activated Carbons ◽  
High Porosity ◽  
Carbon Doped ◽  
Copper Nickel ◽  
Bet Analysis ◽  
Oxygen Groups

Carbon materials with high porosity and surface area such as activated carbons with a combination of metal possess great materials to obtain maximum hydrogen adsorption via the hydrogen spillover effect. The properties of activated carbon doped with metals (copper, nickel and palladium) were studied to evaluate the capacity of hydrogen sorption on the materials. Characteristics of the activated carbon doped with copper (AC-Cu), nickel (AC-Ni) and palladium (AC-Pd) were evaluated using particle density test, Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD) and surface and pore analysis (BET). The performance of hydrogen adsorption of the materials was carried out at different pressures of 50, 100 and 150 psi. Characterization of the materials shows that FTIR spectroscopy manage to detect surface functional groups meanwhile the carbon structure and metal content was determined using XRD. BET analysis shows the presence of oxygen groups was decrease the specific surface area whereas the presence of transition metals had increased the surface area. Hydrogen adsorption test at 150 psi indicates that oxygen groups are not a good adsorption characteristic with only a maximum of 0.39 wt% of hydrogen was adsorbed compared to pristine activated carbon’s 0.42 wt% at 150 psi. The presence of transition metals, copper, nickel and palladium increased the overall hydrogen uptake with 0.52 wt%, 0.44 wt% and 0.62 wt% respectively at 150 psi.

scholarly journals Parabens Adsorption onto Activated Carbon: Relation with Chemical and Structural Properties

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4313 ◽  
Author(s):  
Astrid Roxanna Moreno-Marenco ◽  
Liliana Giraldo ◽  
Juan Carlos Moreno-Piraján
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Surface Area ◽  
Endocrine Disruptor ◽  
Emerging Contaminants ◽  
Activated Carbons ◽  
Elaeis Guineensis ◽  
Acid Sites ◽  
Co2 Atmosphere

Parabens (alkyl-p-hidroxybenzoates) are antimicrobial preservatives used in personal care products, classified as an endocrine disruptor, so they are considered emerging contaminants. A raw version of activated carbons obtained from African palm shell (Elaeis guineensis) modified chemically by impregnation with salts of CaCl2 (GC2), MgCl2 (GM2) and Cu(NO3)2 (GCu2) at 2% wt/v and carbonized in CO2 atmosphere at 1173 K was prepared. The process of adsorption of methyl (MePB) and ethylparaben (EtPB) from aqueous solution on the activated carbons at 18 °C was studied and related to the interactions between the adsorbate and the adsorbent, which can be quantified through the determination of immersion enthalpies in aqueous solutions of corresponding paraben, showing the lowest-value carbon GM2, which has a surface area of 608 m2 × g−1, while the highest values correspond to the activated carbon GCu2, with a surface area of 896 m2 × g−1 and the highest content of surface acid sites (0.42 mmol × g−1), such as lactonic and phenolic compounds, which indicates that the adsorbate–adsorbent interactions are favored by the presence of these, with interaction enthalpies that vary between 5.72 and 51.95 J × g−1 for MePB adsorption and 1.24 and 52.38 J × g−1 for EtPB adsorption showing that the process is endothermic.

Modification of Activated Carbon and its Application on Adsorption of UDMH Gas

2013 ◽  
Vol 634-638 ◽  
pp. 1026-1030 ◽  
Author(s):  
Huan Chun Wang ◽  
Xiao Li Gou ◽  
Xiao Meng Lv
Keyword(s):  
Activated Carbon ◽  
High Temperature ◽  
Transition Metal ◽  
Surface Structure ◽  
Functional Groups ◽  
Room Temperature ◽  
Activated Carbons ◽  
Metal Solution ◽  
Modified Activated Carbons

Two kinds of modified activated carbons were prepared by dipping with Zn(NO3)2 solution and by reducing in the atmosphere of N2 at high temperature respectively, which were characterized by FTIR,DSC,SEM and EDS. The surface structure was strongly changed in the process, along with the changes of chemical functional groups. The results of adsorption experiments revealed that the adsorbent capacities of UDMH gas at room temperature were enhanced obviously by modification compared with the raw activated carbon, especially dipped by transition metal solution. The mechanism probably involved was also discussed.

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