Thermodynamics of adsorption of acetone on active carbon supported metal adsorbents

1992 ◽  
Vol 270 (9) ◽  
pp. 917-926 ◽  
Author(s):  
M. Afzal ◽  
F. Mahmood ◽  
M. Saleem
Keyword(s):  
Active Carbon ◽  
Thermodynamics Of Adsorption ◽  
Supported Metal

Carbon Fibrils Mechanism of Growth and Utilization as a Catalyst Support

1994 ◽  
Vol 368 ◽  
Author(s):  
John W. Geus ◽  
A. J. Van Dillen ◽  
Marco S. Hoogenraad
Keyword(s):  
Mechanical Strength ◽  
Active Carbon ◽  
Circular Cross Section ◽  
Metal Particles ◽  
High Dispersion ◽  
Average Pore ◽  
High Mechanical Strength ◽  
Very High ◽  
Mechanism Of Growth ◽  
Supported Metal

ABSTRACTEspecially with the production of fine chemicals catalytic reactions are being performed in which solid catalysts suspended in liquids are used. Carbon is stable in both acid and alkaline liquids and is not preferentially wetted by water. Carbon is therefore an attractive support for catalysts to be used in liquid-phase reactions. The relatively low diffusion coefficients in liquids call for catalyst bodies having wide pores and dimensions between 1 and 10 μm. Since particles smaller than 1 μm cannot be readily separated from liquids, attrition of carbon support bodies must be avoided. However, it is difficult to produce active carbon bodies of 1 to 10 μm of a high mechanical strength. Also with gas-phase reactions, the low mechanical strength of active carbon bodies limits the applicability of active carbon.From supported metal particles carbon filaments of a diameter between 10 and 300 nm can be grown rapidly. The diameter is generally of the same order of magnitude as the size of the metal particles. The graphite layers within the fibrils, that have a circular cross-section, are oriented either parallel to the fibril axis or at an angle, which leads to cone-shaped graphite layers. The mechanism of growth of carbon fibrils from supported metal particles will be dealt with. The parallel orientation of the graphite layers leads to a very high mechanical strength, while the porous structure is extremely open. A representative value for the surface area is 225 m2/g and for the pore volume 1.6 ml/g, which leads to an average pore dimension of 28 nm.To apply active precursors, such as, palladium salts, the surface of the carbon fibrils must be oxidized, e.g., by treatment with nitric acid. A very high dispersion of palladium can thus be achieved. The dispersion of components active in hydrogenation can be assessed by the ability to react the support with hydrogen to methane. The activity of catalyst on carbon fibrils in the hydrogenation of nitrobenzene as well as the filterability of carbon fibril catalysts will be compared with that of commercial catalysts.

Thermodynamics of adsorption of krypton, xenon, nitrogen, and oxygen on microporous active carbon at temperatures above critical values

2013 ◽  
Vol 49 (4) ◽  
pp. 367-372 ◽  
Author(s):  
T. A. Kuznetsova ◽  
A. M. Tolmachev ◽  
N. G. Kryuchenkova ◽  
D. A. Firsov ◽  
A. A. Fomkin
Keyword(s):  
Active Carbon ◽  
Critical Values ◽  
Thermodynamics Of Adsorption

Thermodynamics of adsorption of organic vapors on metal-loaded active carbon

Carbon ◽  
1993 ◽  
Vol 31 (5) ◽  
pp. 757-764 ◽  
Author(s):  
M. Afzal ◽  
F. Mahmood ◽  
M. Saleem
Keyword(s):  
Active Carbon ◽  
Organic Vapors ◽  
Thermodynamics Of Adsorption

HREM image simulations for supported metal particle catalysts

1993 ◽  
Vol 51 ◽  
pp. 736-737 ◽  
Author(s):  
Ming-Hui Yao ◽  
David J. Smith
Keyword(s):  
Fine Particles ◽  
Amorphous Material ◽  
Chemical Properties ◽  
Morphological Features ◽  
Metal Particles ◽  
Plan View ◽  
Profile View ◽  
Imaging Conditions ◽  
Image Simulations ◽  
Supported Metal

The chemical properties of catalysts often depend on the size, shape and structure of the supported metal particles. To characterize these morphological features and relate them to catalysis is one of the main objectives for HREM study of catalysts. However, in plan view imaging, details of the shape and structure of ultra-fine supported particles (<2nm) are often obscured by the overlapping contrast from the support, and supported sub-nanometer particles are sometimes even invisible. Image simulations may help in the interpretation at HREM images of supported particles in particular to extract useful information about the size, shape and structure of the particles. It should also be a useful tool for evaluating the imaging conditions in terms of visibility of supported particles. P. L. Gai et al have studied contrast from metal particles supported on amorphous material using multislice simulations. In order to better understand the influence of a crystalline support on the visibility and apparent morphological features of supported fine particles, we have calculated images of Pt and Re particles supported on TiO2(rutile) in both plan view and profile view.

PEMANFAATAN KARBON AKTIF UNTUK MENGURANGI CEMARAN FORMALIN PADA IKAN ASIN JAMBAL ROTI

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Erma Ayu Nurcahyani ◽  
Merkuria Karyantina ◽  
Nanik Suhartatik
Keyword(s):  
Active Carbon ◽  
Food Preservation ◽  
Hazardous Substances ◽  
Salted Fish ◽  
Hazardous Chemical ◽  
The People ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
Safe Food ◽  
Chemical Material

Ikan asin adalah metode untuk pengawetan makanan menggunakan kombinasi penggaraman dan pengeringan matahari. Di kalangan masyarakat, pembuatan ikan asin banyak menggunakan bahan kimia berbahaya seperti formalin. Penambahan bahan berbahaya mempengaruhi kualitas terutama keamanan. Makanan yang aman didefinisikan sebagai makanan yang terbebas dari cemaran biologi, kimia, mikrobiologi, yang dapat mempengaruhi kesehatan. Karbon aktif diduga bersifat polar yang mampu mengadsorpsi formalin. Tujuan penelitian ini adalah untuk mengetahui pengaruh pemberian karbon aktif dalam mengurangi cemaran formalin pada “jambal roti”. Rancangan percobaan yang digunakan untuk percobaan yaitu Rancangan Acak Lengkap (RAL) 2 faktorial, dengan faktor pertama yaitu konsentrasi karbon aktif 0, 3, dan 6% serta perlakuan kedua yaitu lama perebusan selama 5, 10, dan 15 menit. Penelitian ini dimulai dari pembuatan “jambal roti” dengan penambahan formalin dan perebusan dengan karbon aktif kemudian dianalisis uji kadar formalin, NaCl, protein, dan air. Hasil penelitian menunjukkan bahwa konsentrasi karbon aktif dan lama perebusan memberikan pengaruh yang signifikan pada kualitas jambal roti. Semakin tinggi konsentrasi karbon aktif dan lama perebusan maka semakin berkurangnya kadar formalin pada jambal roti. Hasil terbaik penelitian ini adalah karbon aktif 6% dan lama perebusan 15 menit. Menghasilkan formalin 3.21 ppm, NaCl 9.40%, protein 42.00%, dan air 30.02%. Kata kunci: Karbon Aktif, Formalin, Jambal Roti, Lama Perebusan. ABSTRACT                 Salted fish was a method for food preservation using combination of salting and sun drying. Among the people, the manufacture of salted fish use hazardous chemical material such as formaldehyde. The addition of hazardous substances affects the quality especially the safety. Safe food define as food that free from biological, chemical, microbiological contaminants that can affect health. Active carbon suspected to be polar which able to adsorb formaldehyde. The purpose of this research was to determine the influence of active carbon in reducing formaldehyde in salted fish “jambal roti”. The research used completely randomized design (CRD) with 2 factors, the first factor was the concentration of active carbon 0, 3, and 6% and the second was the boiling time (for 5, 10, and 15 min). This research was started from making “jambal roti” with the addition of formaldehyde and boiling with active carbon then analyzed for formaldehyde content, NaCl, protein, and moisture. The result showed that the concentration of active carbon and boiling time had a significant effect in quality salted fish “jambal roti”. The higher the concentration of active carbon and boiling time the more formaldehyde in “jambal roti” were removed. The best results of the research was 6% active carbon and 15 min of boiling time. Resulting 3.21 ppm of formaldehyde, 9.40% of NaCl, 42.00% of protein, and 30.02% of moisture. Keywords: Active Carbon, Formaldehyde, Jambal Roti, Boiling Time

Nano-silver active carbon fiber dressings improving bedsore wound healing in rats

2015 ◽  
Vol 36 (10) ◽  
pp. 1051 ◽  
Author(s):  
Ying WANG ◽  
Jian-xing SONG ◽  
Jiang-ping CHEN ◽  
Xiao-li LOU
Keyword(s):  
Wound Healing ◽  
Carbon Fiber ◽  
Active Carbon ◽  
Nano Silver

Analysis of the pore structure of adsorbents and its characterization by a numerical method

1984 ◽  
Vol 49 (12) ◽  
pp. 2721-2738 ◽  
Author(s):  
Ondřej Kadlec ◽  
Jerzy Choma ◽  
Helena Jankowska ◽  
Andrzej Swiatkowski
Keyword(s):  
Distribution Function ◽  
Pore Structure ◽  
Numerical Method ◽  
Active Carbon ◽  
Numerical Evaluation ◽  
Suggested Algorithm

This paper describes the algorithm of numerical evaluation of the parameters of the pore structure of adsorbents ( the micro, mezo and macropores). The structure of individual types of pores is described with the equation proposed by one of the present authors and giving the total distribution function of the pores with respect to their radii. The reliability of the suggested algorithm was verified in a number of calculations using a specially developed program. The results of the analysis and characterization of three different specimens of active carbon are shown as an example.

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