Effective cesium removal from Cs-containing water using chemically activated opaline mudstone mainly composed of opal-cristobalite/tridymite (opal-CT)

AbstractOpaline mudstone (OM) composed of opal-CT (SiO2·nH2O) has high potential use as a cesium (Cs) adsorbent, due to its high specific surface area (SSA). The objective of this study was to investigate the Cs adsorption capacity of chemically activated OM and the adsorption mechanism based on its physico-chemical properties. We used acid- and base-activation methods for the surface modification of OM. Both acid- and base- activations highly increased the specific surface area (SSA) of OM, however, the base-activation decreased the zeta potential value more (− 16.67 mV), compared to the effects of acid-activation (− 6.60 mV) or non-activation method (− 6.66 mV). Base-activated OM showed higher Cs adsorption capacity (32.14 mg/g) than the others (acid: 12.22 mg/g, non: 15.47 mg/g). These results indicate that base-activation generates pH-dependent negative charge, which facilitates Cs adsorption via electrostatic attraction. In terms of the dynamic atomic behavior, Cs cation adsorbed on the OM mainly exist in the form of inner-sphere complexes (IS) containing minor amounts of water molecules. Consequently, the OM can be used as an effective Cs adsorbent via base-activation as an economical and simple modification method.

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Characterization of Samarium Doped Ceria Powders Having High Specific Surface Area Synthesized by Carbon-Assisted Spray Pyrolysis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.485.137 ◽

2011 ◽

Vol 485 ◽

pp. 137-140 ◽

Cited By ~ 2

Author(s):

Kenichi Myoujin ◽

Hiroki Ichiboshi ◽

Takayuki Kodera ◽

Takashi Ogihara

Keyword(s):

Specific Surface ◽

Relative Density ◽

Spray Pyrolysis ◽

Surface Area ◽

Specific Surface Area ◽

Carbon Sources ◽

Chemical Properties ◽

High Specific Surface Area ◽

Doped Ceria ◽

Physical And Chemical

Spherical samarium doped ceria (Ce0.8Sm0.2O1.9, SDC) powders having high specific surface area (SSA) were successfully synthesized by carbon-assisted spray pyrolysis (CASP). Saccharides, such as monosaccharides and disaccharides, or organic acids were used as carbon sources. The physical and chemical properties of these powders were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), Thermo gravimetry-Differential Thermal Analysis (TG-DTA), and BET. Decarbonized powders obtained by this method exhibit spherical morphologies and nano- and submicron-sizes. The SSA of SDC obtained from CASP was more than seven times higher than that obtained from conventional spray pyrolysis (CSP). The SSA of the decarbonized SDC powders obtained by calcination at 900 °C was estimated to be approximately 70 m2/g by using the BET method. The relative density of SDC obtained from CASP was higher than that obtained from CSP. The relative density of the SDC pellet was highest (96 %) when it was sintered at 1400 °C.

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SYNTHESIS AND CHARACTERIZATION OF PHOTOCATALYS Fe2O3 PILLARED MONTMORILLONITE DOPED TiO2 AND ITS APPLICATION FOR RHODAMINE B PHODODEGRADATION USING VISIBLE LIGHT IRRADIATION

Jurnal Kimia ◽

10.24843/jchem.2020.v14.i01.p14 ◽

2020 ◽

pp. 82

Author(s):

D. A. D. N. Dewi ◽

I N. Simpen ◽

I W. Suarsa

Keyword(s):

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Rhodamine B ◽

High Specific Surface Area ◽

Montmorillonite Clay ◽

Pillared Montmorillonite ◽

Bet Method ◽

Acid And Base

A montmorillonite clay modified with semiconductor metal can act as a photocatalyst material. Montmorillonite clays were chosen because of their natural characteristics which are easily to be modified and have high specific surface area. This research aims to modify montmorillonite clay into photocatalyst material. The montmorillonite clay was intercalated using Fe2O3 to produce Fe2O3-pillared montmorillonite clay, then doped with TiO2 to form a photocatalyst material Fe2O3-PILC / TiO2. Modifications were intended to increase the specific surface area and number of active photocatalyst sites and thus increase the ability of photodegradation. The characterization carried out included characterizing the pillar formation using X-ray Diffraction (XRD), specific surface area by the BET method (Bruneau, Emmet, and Teller), a the number of surface acid-base sites by the titration method. Photocatalyst with the best character was Fe2O3-PILC / TiO2 1: 3 with specific surface area, number of acid and base sites respectively 45,947 m2/g, 20,1736 x 1023 sites/gram and 19,0044 x 1023 sites/gram. The result of photodegradation at optimum condition with visible light at pH 3 using 400 mg photocatalyst was 99.84%. Keywords: photocatalyst, Fe2O3, montmorillonite clay, TiO2, rhodamine B

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Mineralogical and physico-chemical properties of four Thai soils with Special Reference to specific surface area (SSA) and zero point of charge (ZPC)

Soil Science & Plant Nutrition ◽

10.1080/00380768.1996.10414692 ◽

1996 ◽

Vol 42 (1) ◽

pp. 93-103 ◽

Cited By ~ 6

Author(s):

Katsutoshi Sakurai ◽

Shinichi Kozasa ◽

Bunyarit Puriyakorn ◽

Pornchai Preechapanya ◽

Virat Tanpibal ◽

...

Keyword(s):

Specific Surface ◽

Special Reference ◽

Surface Area ◽

Specific Surface Area ◽

Chemical Properties ◽

Zero Point ◽

Zero Point Of Charge ◽

Physico Chemical

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SYNTHESIS, STRUCTURE AND PROPERTIES OF ORGANIC GELS BASED ON LARCH BARK TANNINS AND HY-DROLYSIS LIGNIN

chemistry of plant raw material ◽

10.14258/jcprm.2021029635 ◽

2021 ◽

pp. 109-122

Author(s):

Nadezhda Mikhailovna Mikova ◽

Elena Valentinovna Mazurova ◽

Ivan Petrovich Ivanov ◽

Boris Nikolayevich Kuznetsov

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Furfuryl Alcohol ◽

Lignin Content ◽

Sol Gel ◽

Chemical Properties ◽

Hydrolysis Lignin ◽

Physico Chemical ◽

Gel Composition

For the first time, tannin-lignin-formaldehyde and tannin-lignin-furfuryl organic gels were obtained on the basis of larch bark tannins and hydrolysis lignin by sol-gel condensation with formaldehyde and furfuryl alcohol. Their physico-chemical properties were studied by varying the content of lignin (from 5 to 30 wt%) and a fixed mass ratio of polyphenolic substances to the crosslinking reagent (1 : 1.5). With an increase in the lignin content the density of tannin-lignin formaldehyde gels decreases from 0.83 to 0.53 g/ cm3, and that of tannin-lignin-furfuryl gels is from 0.32 to 0.14 g / cm3. According to the FTIR data, the structures of tannin-lignin-formaldehyde and tannin-lignin-furfuryl gels are formed by aromatic fragments cross-linked with methylene and methylene-ether bridges. Scanning electron microscopy shows that the addition of appropriate amounts of lignin to tannins (up to 10 wt% when using formaldehyde and up to 20 wt% when using furfuryl alcohol) promotes the formation of gels with a more developed porous structure. In the case of tannin-lignin-formaldehyde gel, the specific surface area and sorption of methylene blue are 12 m2 / g and 43 mg / g and for tannin-lignin-furfuryl gel – 72 m2 / g and 114.5 mg/g, respectively. It was found that an increase in the lignin content in the gel composition over 20 wt.% is accompanied by the phase localization of lignin (precipitation), which reduces the strength of the resulting gel and reduces its specific surface area.

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Physico-chemical Characteristics of Pulverized Coals and Their Interrelations- A Spontaneous Combustion and Explosion Perspective

10.21203/rs.3.rs-828214/v1 ◽

2021 ◽

Author(s):

Devi Prasad Mishra

Keyword(s):

Particle Size ◽

Specific Surface ◽

Bulk Density ◽

Adsorption Capacity ◽

Surface Area ◽

Specific Surface Area ◽

Spontaneous Combustion ◽

Chemical Characteristics ◽

Physico Chemical ◽

Coal Particles

Abstract Characteristics of pulverized coals have significant influence on the spontaneous combustion and explosion processes. This paper presents an experimental and theoretical framework on physico-chemical characteristics of coal and analyzes their interrelations from spontaneous combustion and explosion perspectives. The chemical properties, morphology, bulk density, particle size and specific surface area of pulverized coals from nine different coal subsidiaries of India are vividly investigated in five distinct sizes. Moreover, the effects of particle size on bulk density, specific surface area and N2 adsorption capacity of pulverized coals are critically analyzed. The micrographs revealed that the coal particles are mostly irregular in shape with angular outlines and sharp edges. With decrease in particle size, the bulk density of pulverized coals decreased and the specific surface area and N2 adsorption capacity increased. The relationships of bulk density and specific surface area of pulverized coals with particle size are established. Moreover, the specific surface areas determined by both the particle sizing and BET methods are compared and correlation factors between them are determined. This study led to the generation of insightful coal characteristic data which can be used as reference material for furthering researches on spontaneous combustion and explosion involving pulverized coals.

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Preparation of lightweight and high specific surface area ceramsites with sewage sludge

JOURNAL OF SHENZHEN UNIVERSITY SCIENCE AND ENGINEERING ◽

10.3724/sp.j.1249.2014.04374 ◽

2014 ◽

Vol 31 (4) ◽

pp. 374

Author(s):

Ziyi Su ◽

Jiang Yu ◽

Ci Wang ◽

Jianquan Liu ◽

Jin Hu

Keyword(s):

Sewage Sludge ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

High Specific Surface Area

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Nanoporous Quasi-High-Entropy Alloy Microspheres

Metals ◽

10.3390/met9030345 ◽

2019 ◽

Vol 9 (3) ◽

pp. 345 ◽

Cited By ~ 3

Author(s):

Lianzan Yang ◽

Yongyan Li ◽

Zhifeng Wang ◽

Weimin Zhao ◽

Chunling Qin

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

High Specific Surface Area ◽

High Entropy Alloy ◽

Face Centered Cubic ◽

High Entropy ◽

Hierarchical Porous

High-entropy alloys (HEAs) present excellent mechanical properties. However, the exploitation of chemical properties of HEAs is far less than that of mechanical properties, which is mainly limited by the low specific surface area of HEAs synthesized by traditional methods. Thus, it is vital to develop new routes to fabricate HEAs with novel three-dimensional structures and a high specific surface area. Herein, we develop a facile approach to fabricate nanoporous noble metal quasi-HEA microspheres by melt-spinning and dealloying. The as-obtained nanoporous Cu30Au23Pt22Pd25 quasi-HEA microspheres present a hierarchical porous structure with a high specific surface area of 69.5 m2/g and a multiphase approximatively componential solid solution characteristic with a broad single-group face-centered cubic XRD pattern, which is different from the traditional single-phase or two-phase solid solution HEAs. To differentiate, these are named quasi-HEAs. The synthetic strategy proposed in this paper opens the door for the synthesis of porous quasi-HEAs related materials, and is expected to promote further applications of quasi-HEAs in various chemical fields.

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KCl-assisted activation: Moringa oleifera branch-derived porous carbon for high performance supercapacitor

New Journal of Chemistry ◽

10.1039/d1nj00046b ◽

2021 ◽

Vol 45 (12) ◽

pp. 5712-5719

Author(s):

Yongxiang Zhang ◽

Peifeng Yu ◽

Mingtao Zheng ◽

Yong Xiao ◽

Hang Hu ◽

...

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Porous Carbon ◽

High Performance ◽

Moringa Oleifera ◽

High Specific Surface Area ◽

Porous Carbons

Porous carbons with a high specific surface area (2314–3470 m2 g−1) are prepared via a novel KCl-assisted activation strategy for high-performance supercapacitor.

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