The Adsorption/Desorption Dynamics Properties of N-Alkanes in Light Naphtha on 5A Zeolites

Self-made JH4 zeoite was characterized by BET, mercury and other methods. The dynamic adsorption capacity of nC5/nC6 in light naphtha on JH4 zeolite fixed bed was investigated. The effect of cyclic purge exhaust composition, which simulate different condensation conditions, on desorption performance of JH4 zeolite bed was studied. The results shows that, the microporous BET specific surface area and pore volume of JH4 zeolite is 710.05 m2/g and 0.32 cm3/g; macropore specific surface area and pore volume is 3.64 m2/g and 0.29 cm3/g, respectively. Under the adsorption conditions of 0.1 MPa, 165 °C, adsorption capacity of n-pentane and n-hexane in light naphtha on JH4 zeolite reaches, 7.24 g/100gadsand 3.11 g/100gadsrespectively.If the content of pentane and hexane achieves 3.68% and 0.21% in nitrogen purge gas, total desorption amount of JH4 zeolite is 2.07 g/100gads, falling 60.19% than that of pure N2purge.

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Study of the Porous Structure and High Adsorption Capacity of Biomass-Based Activated Carbon Prepared from Aspen Wood by Ferric Nitrate III Activation

Journal of Biobased Materials and Bioenergy ◽

10.1166/jbmb.2021.2047 ◽

2021 ◽

Vol 15 (2) ◽

pp. 131-144

Author(s):

Chunjiang Jin ◽

Huimin Chen ◽

Luyuan Wang ◽

Xingxing Cheng ◽

Donghai An ◽

...

Keyword(s):

Activated Carbon ◽

Specific Surface ◽

Adsorption Capacity ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Mass Ratio ◽

Aspen Wood ◽

Surface Functional Groups ◽

Wood Sawdust

In this study, aspen wood sawdust was used as the raw material, and Fe(NO3)3 and CO2 were used as activators. Activated carbon powder (ACP) was produced by the one-step physicochemical activation method in an open vacuum tube furnace. The effects of different mass ratios of Fe(NO3)3 and aspen wood sawdust on the pore structure of ACP were examined under single-variable experimental conditions. The mass ratio was 0–0.4. The detailed characteristics of ACP were examined by nitrogen adsorption, scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The adsorption capacity of ACP was established by simulating volatile organic compounds (VOCs) using ethyl acetate. The results showed that ACP has a good nanostructure with a large pore volume, specific surface area, and surface functional groups. The pore volume and specific surface area of Fe-AC-0.3 were 0.26 cm3/g and 455.36 m2/g, respectively. The activator played an important role in the formation of the pore structure and morphology of ACP. When the mass ratio was 0–0.3, the porosity increased linearly, but when it was higher than 0.3, the porosity decreased. For example, the pore volume and specific surface area of Fe-AC-0.4 reached 0.24 cm3/g and 430.87 m2/g, respectively. ACP presented good VOC adsorption performance. The Fe-AC-0.3 sample, which contained the most micropore structures, presented the best adsorption capacity for ethyl acetate at 712.58 mg/g. Under the action of the specific reaction products nitrogen dioxide (NO2) and oxygen, the surface of modified ACP samples showed different rich C/O/N surface functional groups, including C-H, C=C, C=O, C-O-C, and C-N.

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The Effect of NaOH and KOH on the Characterization of Mesoporous AlOOH Nanostructures in the Hydrothermal Route

Journal of the Mexican Chemical Society ◽

10.29356/jmcs.v58i2.163 ◽

2017 ◽

Vol 58 (2) ◽

Cited By ~ 3

Author(s):

Nahid Haghnazari ◽

Mozaffar Abdollahifar ◽

Farahnaz Jahani

Keyword(s):

Specific Surface ◽

Surface Area ◽

Hydrothermal Treatment ◽

Specific Surface Area ◽

Analytical Techniques ◽

Aluminium Nitrate ◽

Hydrothermal Route ◽

Bet Specific Surface Area ◽

Adsorption Desorption

Mesoporous AlOOH was synthesized by hydrothermal treatment from aluminium nitrate and NaOH or KOH. The effect of NaOH and KOH as precipitating agents on the characterization of samples were investigated. xrd, ftir, fesem and N<sub>2</sub> adsorption-desorption analytical techniques were used to characterize the products. Our results showed that using KOH as precipitating agent was favourable for the formation of mesoporous and crystalline AlOOH with high bet-specific surface area of 98 m<sup>2</sup>/g.

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The influence factors for gas adsorption with different ranks of coals

Adsorption Science & Technology ◽

10.1177/0263617417730186 ◽

2017 ◽

Vol 36 (3-4) ◽

pp. 904-918 ◽

Cited By ~ 6

Author(s):

Deyong Guo ◽

Xiaojie Guo

Keyword(s):

Moisture Content ◽

Specific Surface ◽

Pore Structure ◽

Adsorption Capacity ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Gas Adsorption ◽

Total Pore Volume ◽

Factors Influencing

In this paper, scanning electron microscopy, low-temperature N2 adsorption and CH4 isothermal adsorption experiments were performed on 11 coal samples with Ro,max between 0.98 and 3.07%. The pore structure characteristics of coals (specific surface area, total volume distribution) were studied to assess the gas adsorption capacity. The results indicate that there is significant heterogeneity on coal surface, containing numerous channel-like pores, bottle-shaped pores and wedge-shaped pores. Both Langmuir volume (VL) and Langmuir pressure (PL) show a stage change trend with the increase of coalification degree. For different coalification stages, there exist different factors influencing the VL and PL values. For low-rank coals (Ro,max < 1.1%), the increase of VL values and decrease of PL values are mainly due to the abundant primary pore and fracture within coal. For middle-rank coals (1.1% < Ro,max < 2.1%), the moisture content, vitrinite content and total pore volume are all the factors influencing VL, and the reduction of PL is mainly attributed to the decrease of moisture content and inertinite content. Meanwhile, this result is also closely related to the pore shape. For high-rank coals (Ro,max > 2.1%), VL values gradually increase and reach the maximum. When the coal has evolved into anthracite, liquid hydrocarbon within pore begins pyrolysis and gradually disappears, and a large number of macropores are converted into micropores, leading to the increase of specific surface area and total pore volume, corresponding to the increase of VL. In addition, the increase of vitrinite content within coal also contributes to the increase of VL. PL, reaches the minimum, indicating that the adsorption rate reaches the largest at the low pressure stage. The result is mainly controlled by the specific surface area and total pore volume of coal samples. This research results will provide a clearer insight into the relationship between adsorption parameters and coal rank, moisture content, maceral composition and pore structure, and it is of great significance for better assessing the gas adsorption capacity.

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Synthesis of micro-mesopores flowerlike γ-Al2O3 nano-architectures

Journal of the Serbian Chemical Society ◽

10.2298/jsc130903007a ◽

2014 ◽

Vol 79 (8) ◽

pp. 1007-1017 ◽

Cited By ~ 18

Author(s):

Mozaffar Abdollahifar ◽

Reza Zamani ◽

Ehsan Beiygie ◽

Hosain Nekouei

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Total Pore Volume ◽

High Specific Surface Area ◽

X Ray Diffraction ◽

N2 Adsorption ◽

X Ray ◽

Adsorption Desorption

The micro-mesopores flowerlike ?-Al2O3 nano-architectures have been synthesized by thermal decomposition method using the synthesized AlOOH (boehmite) as precursor. After calcination at 500?C for 5 h, the obtained flowerlike ?-Al2O3 has similar structure like the AlOOH precursor. X-ray diffraction (XRD), FTIR, TG, FESEM and TEM techniques were used to characterize morphology and structure of the synthesized samples. The specific surface area (BET), pore volume and pore-size distribution of the products were determined by N2 adsorption-desorption measurements. The flowerlike ?-Al2O3 showed BET high specific surface area 148 m2 g-1 with total pore volume 0.59 cm3 g-1.

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THE STABILIZING OF ANATASE AEROGEL AT HIGH TEMPERATURE

Indonesian Journal of Chemistry ◽

10.22146/ijc.21863 ◽

2010 ◽

Vol 4 (2) ◽

pp. 110-116 ◽

Cited By ~ 1

Author(s):

Silvester Tursiloadi ◽

Hiroshi Hirashima

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Anatase Phase ◽

Total Pore Volume ◽

Average Pore ◽

Amorphous Sio2 ◽

Bet Specific Surface Area ◽

Sio2 Aerogel

Stable anatase is attractive to its notable functions for photo catalysis and photon-electron transfer. Stable anatase TiO2 containing amorphous SiO2 aerogel was prepared by hydrolysis of Ti (OC3H7)4 and Si (OC3H7)4 in a 2-propanol solution with acid catalyst. The solvent in wet gels was supercritically extracted in CO2 at 60 oC and 22 Mpa. Thermal evolutions of the microstructure of the gels were evaluated by TGA-DTA, N2 adsorption and XRD. A stable anatase TiO2 containing amorphous SiO2 aerogel with a BET specific surface area of 365 m2/g and a total pore volume of 0.20 cm3/g was obtained as prepared condition. The anatase phase was stable after calcination up to 1000 oC, and BET specific surface area, total pore volume and average pore diameter did not change significantly after calcination up to 900 oC. Keywords: Supercritical extraction, sol-gel, aerogel, stable anatase structure

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Synthesis of 9-phenylcarbazole hyper-cross-linked polymers in different conditions and adsorption behavior for carbon dioxide

10.3762/bxiv.2019.80.v1 ◽

2019 ◽

Author(s):

Dandan Fang ◽

Xiaodong Li ◽

Meishuai Zou ◽

Xiaoyan Guo ◽

Aijuan Zhang

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Reaction Temperature ◽

Pore Volume ◽

High Surface ◽

Total Pore Volume ◽

Synthesis Conditions ◽

Bet Specific Surface Area ◽

Cross Linker

To systematically explore the effects of the synthesis conditions on the porosity of hyper-cross-linked polymers (HCPs), a series of 9-phenylcarbazole HCPs (P1-P11) have been made by changing the dosage of cross-linker, the reaction temperature, catalyst usage and solvent dosage. Fourier transform infrared spectroscopy is utilized to characterize the structure of the obtained polymers. The TG analysis shows a high thermal stability of the HCPs. More importantly, comparative studies on the porous properties reveals that: molar ration of cross-linker and building block is the main factor of BET specific surface area; Improving reaction temperature or the usage of catalyst could increase the total pore volume greatly but sacrifice part of BET specific surface area; Fortunately changing solvent dosage could remedy this situation, that is slightly changing solvent dosage could simultaneously obtain high surface area and high total pore volume. The BET specific surface areas of P3 is up to 769 m2g-1 with narrow pore size distribution and the CO2 adsorption capacity of P11 is up to 52.4 cm3g-1 (273 K/1.00 bar).

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Influence of Synthesis Condition on N2 Adsorption Characteristics of Anatase TiO2 Particles Prepared in an Aqueous Solution

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.388.103 ◽

2008 ◽

Vol 388 ◽

pp. 103-106

Author(s):

Yoshitake Masuda ◽

Kazumi Kato

Keyword(s):

Aqueous Solution ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Anatase Tio2 ◽

N2 Adsorption ◽

Tio2 Particles ◽

Bet Specific Surface Area ◽

Desorption Isotherms ◽

Adsorption Desorption

TiO2 was crystallized to form particles in aqueous solutions containing ammonium hexafluorotitanate and boric acid. XRD diffraction patterns indicated they were in a single phase of anatase TiO2. TiO2 particles prepared at 90 °C exhibited N2 adsorption-desorption isotherms of type IV. BET specific surface area of the particles was estimated to 13 m2/g. On the other hand, TiO2 particles prepared at 50 °C exhibited N2 adsorption-desorption isotherms of type I. BET specific surface area of the particles was estimated to 168 m2/g. Crystal growth of TiO2 was strongly affected by synthesis temperature. Nano-sized pores or surface structure of TiO2 particles prepared at 50 °C would increase N2 adsorption volume to realize high BET specific surface area. Additionally, aqueous solution process described here had an advantage that TiO2 crystallized at ambient temperature. Anatase TiO2 was prepared without annealing at high temperature which caused aggregation of particles and disappearance of surface nanostructures. The particles with large surface area can be thus utilized for catalyst, cosmetic, photocatalyst, dye-sensitized solar cell or sensors.

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Carbazole-functionalized hyper-cross-linked polymers for CO2 uptake based on Friedel–Crafts polymerization on 9-phenylcarbazole

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.279 ◽

2019 ◽

Vol 15 ◽

pp. 2856-2863 ◽

Cited By ~ 4

Author(s):

Dandan Fang ◽

Xiaodong Li ◽

Meishuai Zou ◽

Xiaoyan Guo ◽

Aijuan Zhang

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Reaction Temperature ◽

Pore Volume ◽

Total Pore Volume ◽

Molar Ratio ◽

Co2 Uptake ◽

Bet Specific Surface Area ◽

Cross Linker

To systematically explore the effects of the synthesis conditions on the porosity of hyper-cross-linked polymers (HCPs), a series of 9-phenylcarbazole (9-PCz) HCPs (P1–P11) has been made by changing the molar ratio of cross-linker to monomer, the reaction temperature T 1, the used amount of catalyst and the concentration of reactants. Fourier transform infrared spectroscopy was utilized to characterize the structure of the obtained polymers. The TG analysis of the HCPs showed good thermal stability. More importantly, a comparative study on the porosity revealed that: the molar ratio of cross-linker to monomer was the main influence factor of the BET specific surface area. Increasing the reaction temperature T 1 or changing the used amount of catalyst could improve the total pore volume greatly but sacrificed a part of the BET specific surface area. Fortunately changing the concentration of reactants could remedy this situation. Slightly changing the concentration of reactants could simultaneously obtain a high surface area and a high total pore volume. The BET specific surface areas of P3 was up to 769 m2 g−1 with narrow pore size distribution and the CO2 adsorption capacity of P11 was up to 52.4 cm3 g−1 (273 K/1.00 bar).

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ACID ACTIVATION OF PRRENJAS CLAY MINERAL

JOURNAL OF ENGINEERING & PROCESSING MANAGEMENT ◽

10.7251/jepmen1507037m ◽

2018 ◽

Vol 4 (7) ◽

Author(s):

Altin Mele ◽

Krenaida Taraj ◽

Arjan Korpa

Keyword(s):

Specific Surface ◽

Surface Area ◽

Clay Mineral ◽

Specific Surface Area ◽

Pore Volume ◽

Gas Adsorption ◽

Exchange Capacity ◽

Acid Activation ◽

Composition Structure ◽

Adsorption Desorption

Prrenjas clay mineral is found in southeast Albania and has a high content on bentonite. Theinfluence of the sulphuric acid activation on the composition, structure and surface properties ofPrrenjas clay mineral is investigated in this study by means of elemental chemical analysis, X-RayDiffractometry, IR Spectroscopy and gas adsorption-desorption measurement. H2SO4concentrations of 0.143 M, 0.232 M, 0.371 M, 0.537 M, 0.734 M, 0.927 M and 1.456 M were used inthe treatment of samples. The treatment by increasing the acid concentration brings the leaching ofAl3+, Fe2+, Mg2+ from the clay structure. The specific surface area and the pore volume of the claysamples increases respectively from 83 m2/g and 0.069 cm3/g for the untreated clay to 420 m2/g and0.384 cm3/g for the clay mineral treated with 1.456 M H2SO4 solution. New mesopores were createdduring the acid activation mainly in the range of 2 – 8 nm. For the samples treated with 0.927 Mand 1.456 M solutions the increase in specific surface area and pore volume is very high. Thecationic exchange capacity decreases steadily with the concentration of H2SO4 used for thetreatment.

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