Synthesis of Mesoporous Silica Microspheres by PICA and Pseudomorphic Transformation Using Silica Fume as Silica Source

Monodisperse mesoporous silica microspheres (MSM-SF) were successfully prepared through PICA and pseudomorphic transformation using silica fume as original silica source. The structure and morphology of spheres were quantitatively investigated by Zata potential and particle size analyzer, N2 sorption isotherms, XRD, SEM and TEM. The results showed that the monodisperse spherical mesoporous silica microspheres (MSM-SF) exhibited uniform spherical morphology, worm-like mesoporous, large BET surface area of 559.9m2/g; its BJH average pore size diameter and total pore volume are 3.3nm and 0.12cm3/g, respectively. This preparation method provides a new synthetic strategy to control the particle morphology and structure simultaneously, meanwhile this method can also significantly reduce the cost of synthesis of mesoporous silica microspheres.

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Preparation of Porous Silica Microspheres by Polymerization-Induced Colloid Aggregation Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.898.132 ◽

2014 ◽

Vol 898 ◽

pp. 132-135 ◽

Cited By ~ 3

Author(s):

Jia Li He ◽

Xiu Hua Chen ◽

Wen Jie Zhu ◽

Wen Hui Ma ◽

Yong Yin Xiao ◽

...

Keyword(s):

Average Pore Size ◽

Urea Formaldehyde ◽

Porous Silica ◽

Total Pore Volume ◽

Nitrogen Adsorption ◽

Bet Surface Area ◽

Silica Microspheres ◽

Average Pore ◽

Uf Resin ◽

Adsorption Desorption

The UF resin/SiO2 composites microspheres with particle size of 2μm were successfully prepared by polymerization of silica sol from base-catalyzed hydrolysis of tetraethyl orthosilicate, and urea-formaldehyde via the PICA approach, and then calcination in air to remove organic UF resin and yield porous silica microspheres. The samples were characterized by Zetasizer NanoZS Instrument, SEM and Nitrogen adsorption-desorption isotherms. The results showed that the synthesized porous silica microspheres with a BET surface area of 67.01m2/g, a BJH average pore size diameter of 37.32 nm and a total pore volume of 0.69cm3/g, respectively.

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Preparation of High-Performance Activated Carbon from Coffee Grounds after Extraction of Bio-Oil

Molecules ◽

10.3390/molecules26020257 ◽

2021 ◽

Vol 26 (2) ◽

pp. 257

Author(s):

Jie Ren ◽

Nanwei Chen ◽

Li Wan ◽

Guojian Li ◽

Tao Chen ◽

...

Keyword(s):

Activated Carbon ◽

High Performance ◽

Average Pore Size ◽

Total Pore Volume ◽

Micropore Volume ◽

Bet Surface Area ◽

Average Pore ◽

Activation Temperature ◽

Coffee Grounds ◽

Bio Oil

In this study, a new method for economical utilization of coffee grounds was developed and tested. The resulting materials were characterized by proximate and elemental analyses, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N2 adsorption–desorption at 77 K. The experimental data show bio-oil yields reaching 42.3%. The optimal activated carbon was obtained under vacuum pyrolysis self-activation at an operating temperature of 450 °C, an activation temperature of 600 °C, an activation time of 30 min, and an impregnation ratio with phosphoric acid of 150 wt.%. Under these conditions, the yield of activated carbon reached 27.4% with a BET surface area of 1420 m2·g−1, an average pore size of 2.1 nm, a total pore volume of 0.747 cm3·g−1, and a t-Plot micropore volume of 0.428 cm3·g−1. In addition, the surface of activated carbon looked relatively rough, containing mesopores and micropores with large amounts of corrosion pits.

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Fractal Characteristics and Heterogeneity of the Nanopore Structure of Marine Shale in Southern North China

Minerals ◽

10.3390/min9040242 ◽

2019 ◽

Vol 9 (4) ◽

pp. 242 ◽

Cited By ~ 16

Author(s):

Yu ◽

Ju ◽

Qi ◽

Qiao ◽

Huang ◽

...

Keyword(s):

Pore Volume ◽

North China ◽

Average Pore Size ◽

Fractal Dimensions ◽

Total Pore Volume ◽

Integrated Approach ◽

Bet Surface Area ◽

Average Pore ◽

Marine Shale ◽

Nanopore Structure

The characteristics of the nanopore structure in shale play a crucial role in methane adsorption and in determining the occurrence and migration of shale gas. In this study, using an integrated approach of X-ray diffraction (XRD), N2 adsorption, and field emission scanning electron microscopy (FE-SEM), we systematically focused on eight drilling samples of marine Taiyuan shale from well ZK1 in southern North China to study the characteristics and heterogeneity of their nanopore structure. The results indicated that different sedimentary environments may control the precipitation of clay and quartz between transitional shale and marine shale, leading to different organic matter (OM)–clay relationships and different correlations between total organic carbon (TOC) and mineral content. The shale with high TOC content tended to have more heterogeneous micropores, leading to a higher fractal dimension and a more complex nanopore structure. With the increase of TOC content and thermal evolution of OM, the heterogeneity of the pore structure became more significant. Quartz from marine shale possessed abundant macropores, resulting in a decrease of the Brunauere–Emmette–Teller (BET (BET) surface area (SA) and an increase of the average pore size (APS), while clay minerals developed a large number of micropores which worked together with OM to influence the nanopore structure of shale, leading to the increase of the SA and the decrease of the APS. The spatial order of interlayer pores increased with the increase of mixed-layer illite–smectite (MLIS) content, which naturally reduced the fractal dimensions. In contrast, kaolinite, chlorite, and illite have a small number of nanopores, which might enhance the complexity and reduce the connectivity of the nanopore system by mean of pore-blocking. Taiyuan shale with higher heterogeneity is highly fractal, and its fractal dimensions are principally related to the micropores. The fractal dimensions correlate positively with the SA and total pore volume, suggesting that marine shale with higher heterogeneity may possess a larger SA and a higher total pore volume.

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