Effect of raw material sources on activated carbon catalytic activity for HI decomposition in the sulfur-iodine thermochemical cycle for hydrogen production

As an alternative to means for lowering total cholesterol and low-density lipoprotein (LDL) cholesterol, the paper considers the possibility of using carbon adsorbents. From a medical point of view, the removal of cholesterol with enterosorbents is extremely effective. By binding cholesterol, sorbents reduce the risk of cardiovascular disease. The paper searches for new raw material sources and attempts to create enterosorbents with a high capability to adsorb cholesterol. The aim of the work was to develop adsorbents from spent coffee residue with a large proportion of mesopores, to determine the parameters of the porous structure and to study their adsorption capacity against cholesterol. Samples of activated carbon with a large proportion of mesopores (399 and 465 m2/g) were obtained by the traditional method of carbonization-activation of spent coffee grounds and pre-treated hexane to remove fatty acids. The sorption of cholesterol from alcohol solutions has been studied by spectrophotometric method and its effectiveness for the prevention and treatment of atherosclerosis was proved. It has been shown that a sample of activated carbon from spent coffee residue pre-treated with hexane (maximum value reaches 7.5 mg/g) has the best sorption capacity. The intermediate position is occupied by the sample obtained without pre-treatment with solvent (maximum value reaches 6.3 mg/g). Natural Brand carbon has the weakest sorption characteristics (maximum capacity reaches 5.3 mg/g). It can be stated that the adsorption of cholesterol increases with the growth of the specific surface area of mesopores. The parameters of adsorption processes were calculated using the obtained sorption isotherms. Adsorption isotherms were calculated using the Langmuir and Freundlich equations. It is shown that the values of the maximum adsorption calculated by the Langmuir equation have a good agreement with the experimental data.

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Calculation of the Glaze Recipe for Porcelain Feldspar Products Based on their Molecular Formula Rationalization

Revista de Chimie ◽

10.37358/rc.08.2.1719 ◽

2008 ◽

Vol 59 (2) ◽

pp. 129-134

Author(s):

Ion Teoreanu ◽

Roxana Lucia Dumitrache ◽

Stefania Stoleriu

Keyword(s):

Raw Materials ◽

Computer Programs ◽

Point Of View ◽

Raw Material ◽

Easy Access ◽

Molecular Formula ◽

Design Equation ◽

Material Sources

Any change of the raw material sources for glazes, economically, ecologically motivated, and also from the glaze quality point of view, is conditioned by the molecular formula rationalization and by the variation limits of the molecular formula, respectively. The proper glaze compositions are placed within their limit variation intervals with optimized processing and utilization properties. For this purpose, the rationalization criteria and procedures of molecular formulas are summarized in the present paper, as well as the results referring to their rationalization obtained in the authors� previous work. Thus, one starts from a base of raw materials that are selected, usable and also accessible for the design and producing of the glazes. On these bases the groundwork and the design equation for the glaze recipes are developed, exemplified for a single glaze. For an easy access to results, computer programs are used for an easy access to results.

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Adding the activated carbon of rice husk to increase hydrogen production on water electrolysis

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1034/1/012075 ◽

2021 ◽

Vol 1034 (1) ◽

pp. 012075

Author(s):

Purnami ◽

ING. Wardana ◽

Sudjito ◽

Denny Widhiyanuriyawan ◽

Nurkholis Hamidi

Keyword(s):

Activated Carbon ◽

Hydrogen Production ◽

Rice Husk ◽

Water Electrolysis

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Photocatalytic hydrogen generation using mesoporous silicon nanoparticles: influence of magnesiothermic reduction conditions and nanoparticle aging on the catalytic activity

Nanoscale ◽

10.1039/d0nr07463b ◽

2021 ◽

Vol 13 (4) ◽

pp. 2685-2692

Author(s):

Isabel S. Curtis ◽

Ryan J. Wills ◽

Mita Dasog

Keyword(s):

Catalytic Activity ◽

Hydrogen Production ◽

Silicon Nanoparticles ◽

Hydrogen Generation ◽

Oxide Content ◽

Magnesiothermic Reduction ◽

Mesoporous Silicon ◽

High Crystallinity ◽

Photocatalytic Hydrogen Generation

High crystallinity, low oxide content, and low sintering lead to optimally performing mesoporous Si photocatalysts for solar-driven hydrogen production.

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Efficient photocatalytic hydrogen production of ternary composite constituted by cubic CdS, MoS2 and activated carbon

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.159930 ◽

2021 ◽

Vol 874 ◽

pp. 159930

Author(s):

Jiangfan Sun ◽

Mingcai Yin ◽

Yixian Li ◽

Kaiyue Liang ◽

Yaoting Fan ◽

...

Keyword(s):

Activated Carbon ◽

Hydrogen Production ◽

Ternary Composite ◽

Photocatalytic Hydrogen Production ◽

Cubic Cds

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Colour and Directional Symbolism in Ancestral Pueblo Radial Offerings from Chaco Canyon

Cambridge Archaeological Journal ◽

10.1017/s0959774321000317 ◽

2021 ◽

pp. 1-21

Author(s):

Hannah V. Mattson

Keyword(s):

American Southwest ◽

Raw Material ◽

Chaco Canyon ◽

Assemblage Theory ◽

Ancestral Pueblo ◽

Landscape Features ◽

Material Sources ◽

Regional System ◽

Roof Support

Dedicatory offerings of small colourful objects are often found in pre-Hispanic architectural contexts in the Ancestral Pueblo region of the American Southwest. These deposits are particularly numerous in the roof support pillars of circular ritual structures (kivas) at the site of Pueblo Bonito, Chaco Canyon, which served as the ceremonial hub of the Chacoan regional system between the tenth and twelfth centuries ce. Based on the importance of directionality and colour in traditional Pueblo worldviews, archaeologists speculate that the contents of these radial offerings may likewise reference significant Chacoan cosmographic elements. In this paper, I explore this idea by examining the distribution of colours and materials in kiva pilaster repositories in relation to directional quadrants, prominent landscape features, and raw material sources. I discuss the results in the context of Pueblo cosmology and assemblage theory, arguing that particular colours were polyvalent and relational, deriving their meanings from their positions within interacting and heterogenous assemblages.

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Study on Adsorption Properties of Modified Corn Cob Activated Carbon for Mercury Ion

Energies ◽

10.3390/en14154483 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4483

Author(s):

Yuyingnan Liu ◽

Xinrui Xu ◽

Bin Qu ◽

Xiaofeng Liu ◽

Weiming Yi ◽

...

Keyword(s):

Activated Carbon ◽

Photoelectron Spectroscopy ◽

Adsorption Process ◽

Physical Adsorption ◽

Raw Material ◽

Order Kinetic ◽

Mercury Ions ◽

Corn Cob ◽

Adsorption Time ◽

X Ray

In this study, corn cob was used as raw material and modified methods employing KOH and KMnO4 were used to prepare activated carbon with high adsorption capacity for mercury ions. Experiments on the effects of different influencing factors on the adsorption of mercury ions were undertaken. The results showed that when modified with KOH, the optimal adsorption time was 120 min, the optimum pH was 4; when modified with KMnO4, the optimal adsorption time was 60 min, the optimal pH was 3, and the optimal amount of adsorbent and the initial concentration were both 0.40 g/L and 100 mg/L under both modified conditions. The adsorption process conforms to the pseudo-second-order kinetic model and Langmuir model. Scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Zeta potential characterization results showed that the adsorption process is mainly physical adsorption, surface complexation and ion exchange.

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