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Activated carbons preparation process

A wide variety of carbon materials has been used in this study, including multi-wall carbon nanotubes (sample MWNT) chemically activated multi-wall carbon nanotubes (sample A-MWNT)16, commercially available vapor grown carbon nanofibers (sample NF) sample NF after chemical activation with K.OH (sample A-NF) commercially pitch-based carbon fiber from Kureha Company (sample CF) commercially available activated carbons AX-21 from Anderson Carbon Co., Maxsorb from Kansai Coke and Chemicals and commercial activated carbon fibers from Osaka Gas Co. (A20) a series of activated carbons prepared from a Spanish anthracite (samples named K.UA) and Subituminous coal (Samples H) by chemical activation with KOH as described by D. Lozano-Castello et al.17 18 activated carbon monoliths (ACM) prepared from different starting powder activated carbons by using a proprietry polymeric binder from Waterlink Sutcliffe Carbons, following the experimental process described in the previous paper13. [Pg.79]

In 2009, Onda et al. studied the catalytic activity of sulfonated activated carbon prepared from active carbon and concentrated sulfuric acid [47]. The hydrolysis was performed under hydrothermal conditions at 423 K in a steel autoclave lined with Teflon. After 24 h of reaction, sulfonated carbon afforded high yield of glucose (40 C-%, i.e., based on the total weight consumption of carbon) and nearly no SO4 elution was observed which clearly indicated that the process was heterogeneously catalyzed. As observed above, under hydrothermal conditions, the glucose yield... [Pg.71]

Various organic wastes were carbonized with super-heated water vapor using a rotary drum super-heated water vapor generator (SJH-IOM, Johnson Boiler, Japan) and a rotary kiln (JBT-1OM, Johnson Boiler, Japan). The organic wastes were processed at 623 K for 30 - 90 min. Process data and properties of various carbonized materials are summarized in Table 1. An activated carbon (Granular Shirasagi GS3 x 4/6, Takeda Chemical Industries Ltd., Japan) and an activated carbon prepared for alkaline gas adsorption (GAH 4-8, Cataler Corp., Japan) were used as controls. [Pg.153]

The electrical conductivity is not the same for all carbons.1 This property is not related to adsorptive power, but does depend upon the method used to prepare the carbon. Carbons of high conductivity may be very adsorptive, such as chars made from acid tar, or they may be inactive, such as retort carbon. On the other hand, active carbons prepared by the zinc chloride process as well as unactivated wood charcoal have low conductivity (see Table 15 5). [Pg.352]

Ultrasound irradiation has been used in the process of catalyst preparation. Acoustic irradiation increases the dispersion of the active metal on the support,depassivates the metal, and reduces the particle size to nanometer scale.In the case of palladium supported on active carbon prepared under ultrasound with extremely high surface area, not only was a greater metal dispersion achieved, but a larger penetration of metal inside the pores of the support and an easier elimination of chloride ion were observed as well. ... [Pg.321]

The principle of solvent recovery of activated carbon adsorption has been known for almost a century a process was patented in 1905, but in practice the method was used in 1916 when vapors of volatile substances were recovered by using on activated carbon prepared by using chemical activation with zinc chloride. The solvent recovery became very important during World War 1, due to the shortage of solvents because the war industries needed them in large quantities. [Pg.264]

Laszlo et al. studied the adsorption of phenol and 2.3,4 trichlorophenol from dilute aqueous solutions on a granular activated carbon prepared from PAN by a two-step physical activated process. The adsorption isotherms were Type 1 of the BET classification and followed the Langmuir adsorption equation. The adsorption capacity and the adsorption constant K values, obtained using the Langmuir equation (Table 7.6), were found to depend on the pH of the solution. The results were discussed in terms of the acid-base character of the carbon surface and the acidic character of the two phenols. The effect of pH is more significant in the... [Pg.400]

The result also revealed that, for Hg° adsorption, an activated carbon derived from high-organic sulfur coal dod not benefit from a sulfur impregnation process at 600°C when compared with a sulfur-impregnated activated carbon prepared from... [Pg.481]

Characteristics of Ti02-Loaded Activated Carbons Prepared through Sol-Gel Process... [Pg.192]

The properties of activated carbons are a function of the carbonaceous precursor material and of the preparation conditions used (ref. 1), one of which could be the rate of the activation process. Changes in the activation process rates may be obtained by varying the activation temperature, the partial pressure of the activating agent or by use of a catalyst. Although catalytic carbon gasification has been subject of many investigations (ref. 2), its application to activated carbon preparation has not been widely analyzed. [Pg.367]

Figure 3 includes plots of cumulative pore volume deduced from mercury porosimetry for carbon of series B, activated in CO and steam by the uncatalyzed and catalyzed activation process. Uncatalyzed activation with CO only develops the macroporosity especially in the pore range 70-1500 nm. In the case of steam activation the porosity development occurs in pore sizes below 300 nm, in agreement with the results obtained from N, adsorption. Similar trends are found with carbons of series A. These finding are in agreement with data published previously where the porosity of activated carbons prepared by CO, and steam activation of carbonized plum and olive stones were compared (ref. 7). [Pg.373]

The pore size distribution of activated carbons prepared by catalytic CO, activation is different from that obtained by the usual non-catalytic activation process. In both cases the initial porosity of the starting material is important, but in the catalytic activation the distribution of the catalyst eind its amount play an additional important role. [Pg.375]

Other Uses. The quantity of coal used for purposes other than combustion or processing is quite small (2,6). Coal, especially anthracite, has estabHshed markets for use as purifying and filtering agents in either the natural form or converted to activated carbon (see Carbon). The latter can be prepared from bituminous coal or coke, and is used in sewage treatment, water purification, respirator absorbers, solvent recovery, and in the food industry. Some of these markets are quite profitable and new uses are continually being sought for this material. [Pg.237]

Hydrochloric acid may conveniently be prepared by combustion of hydrogen with chlorine. In a typical process dry hydrogen chloride is passed into a vapour blender to be mixed with an equimolar proportion of dry acetylene. The presence of chlorine may cause an explosion and thus a device is used to detect any sudden rise in temperature. In such circumstances the hydrogen chloride is automatically diverted to the atmosphere. The mixture of gases is then led to a multi-tubular reactor, each tube of which is packed with a mercuric chloride catalyst on an activated carbon support. The reaction is initiated by heat but once it has started cooling has to be applied to control the highly exothermic reaction at about 90-100°C. In addition to the main reaction the side reactions shown in Figure 12.6 may occur. [Pg.314]

The palladium-tin catalysts were prepared by Engelhard on a commercial wood based carbon powder with a BET snrface area of approximately 800 m /g and a median particle size (D50) of 19 microns. The preferred carbon was chosen mainly for having good filtration properties. Catalysts with essentially equivalent activities for selectivity and conversion could also be made on two other similar carbons. The preparation process is proprietary but is based on the well-known adsorption-deposition technique (8). Reduction during the preparation process was accomplished via an Engelhard proprietary method. A series of catalysts containing from 1 to 7.5 wt% palladium and from 0 to 1 wt% tin were prepared by the same technique and provided for the experimental program. [Pg.137]

The absorption property exhibited by active carbon certainly depends on the large specific surface area of the material, though an interpretation that it is based solely on this is incomplete. This is borne out by the fact that equal amounts of two activated carbon specimens, prepared from different raw materials or by different processes and having the same total surface area, may behave differently with regard to adsorption. Such differences can be partly explained in terms of the respective surface properties of the carbon samples and partly in terms of their relative pore structure and pore distribution. Every activated carbon particle is associated with at least two types of pores of distinctly different sizes. They are the macropores and the micropores. The macropores completely permeate each particle and act as wide pathways for the diffusion of material in and out of carbon, but they contribute very little to the total surface area. The micropores are more important since they... [Pg.507]


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See also in sourсe #XX -- [ Pg.54 ]




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Activated carbon preparation

Activation process

Activity preparation

Carbon preparation

Carbonates preparation

Carbonation process

Carbonization process

Preparation processes

Process carbonate

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