Activated charcoal adsorption

Keywords Magnetic adsorbent plasmachemical technology activated charcoal adsorption toxicity magnetically guided transport of drugs oncology. 

Standard Practice for Sampling Atmospheres to Collect Organic Compound Vapors (Activated Charcoal Adsorption Method), D3686, in Annual Book of ASTM Standards, Vol. 11.03, Philadelphia, PA, American Society for Testing and Materials 1983... 

Qadeer, R., Adsorption of cerium ions on activated charcoal, Adsorpt. Sci. Technol., 13(6), 519-526 (1996). 

Serum Acetaminophen Assay Using Activated Charcoal Adsorption and Gas Chromatography Without Derivatizat-ion... 

AdsotptHMi therapy widi activated charcoal. Adsorption is the physical binding of a toxicant to an unabsoibable carrier, whkh is ellmirrated in the fec ... 

For other adsorptives the experimental evidence, though less plentiful than with nitrogen, supports the view that at a given temperature the lower closure point is never situated below a critical relative pressure which is characteristic of the adsorptive. Thus, for benzene at 298 K Dubinin noted a value of 017 on active carbons, and on active charcoals Everett and Whitton found 0-19 other values, at 298 K, are 0-20 on alumina xerogel, 0-20-0-22 on titania xerogel and 017-0-20 on ammonium silicomolybdate. Carbon tetrachloride at 298 K gives indication of a minimum closure point at 0-20-0-25 on a number of solids including... 

Natural gas Hquids are recovered from natural gas using condensation processes, absorption (qv) processes employing hydrocarbon Hquids similar to gasoline or kerosene as the absorber oil, or soHd-bed adsorption (qv) processes using adsorbants such as siHca, molecular sieves, or activated charcoal. Eor condensation processes, cooling can be provided by refrigeration units which frequently use vapor-compression cycles with propane as the refrigerant or by... 

Starek, J., Zukal, A. and Rathousky, J., Comparison of the adsorption of humic acids from aqueous solutions on active carbon and activated charcoal cloths. Carbon, 1994, 32(2), 207 211. 

Turner, L., Improvement of activated charcoal-ammonia adsorption heat pumping/refrigeration cycles. Investigation of porosity and heat/mass transfer characteristics. Ph.D. Thesis, University of Warwick, UK, 1992. 

Charcoal Tubes Reference has been made earlier to adsorption, which is the property of some solid materials, such as activated charcoal, to physically retain solvent vapors on their surfaces. In environmental health testing, the adsorbed vapors are removed, generally with a solvent, in a laboratory. The solvent is then analyzed by physical methods (gas chromatography, etc.) to determine the individual compounds whose vapors, such as benzene, were present in the sampled air. Industrial atmospheric samples can be collected in small glass tubes (4 mm ID) packed with two sections of activated charcoal, separated and retained with fiberglass plugs. To obtain an air sample, the sealed ends of the tube are broken off, and air is drawn through the charcoal at the rate of 1 liter per minute by means... 

Filter aids may be applied in one of two ways. The first method involves the use of a precoat filter aid, which can be applied as a thin layer over the filter before the suspension is pumped to the apparatus. A precoat prevents fine suspension particles from becoming so entangled in the filter medium that its resistance becomes exces-sive. In addition it facilitates the removal of filter cake at the end of the filtration cycle. The second application method involves incorporation of a certain amount of the material with the suspension before introducing it to the filter. The addition of filter aids increases the porosity of the sludge, decreases its compressibility, and reduces the resistance of the cake. In some cases the filter aid displays an adsorption action, which results in particle separation of sizes down to 0.1 /i. The adsorption ability of certain filter aids, such as bleached earth and activated charcoals, is manifest by a decoloring of the suspension s liquid phase. This practice is widely used for treating fats and oils. The properties of these additives are determined by the characteristics... 

Granular media filtration is used for treating aqueous waste streams. The filter media consists of a bed of granular particles (typically sand or sand with anthracite or coal). The anthracite has adsorptive characteristics and hence can be beneficial in removing some biological and chemical contaminants in the wastewater. This material may also be substituted for activated charcoal. 

Certain highly porous solid materials selectively adsorb certain molecules. Examples are silica gel for separation of aromatics from other hydrocarbons, and activated charcoal for removing liquid components from gases. Adsorption is analogous to absorption, but the principles are different. Layers of adsorbed material, only a few molecules thick, are formed on the extensive interior area of the adsorbent - possibly as large as 50,000 sq. ft./lb of material. 

Adsorptive Properties. Substances such as silica gel and activated charcoal can be used to collect (adsorb) certain solids from solution. The adsorber bed may be discarded when depleted or recycled by washing and heating. 

Separation involves adsorption onto activated charcoal. 

Adsorption (in which a gas or liquid is taken up on a solid, e.g. activated charcoal, molecular sieves)... 

The adsorption process, in principle, is an anion-exchange process which is restricted only to the surface of the activated charcoal. This fact makes the loading or the exchange capacity of activated charcoal to be relatively smaller in comparison with ion-exchange resins, and it is for this reason that charcoals are quite often treated suitably to improve their loading capacities. The surface and the pore structure characteristics of activated carbon are the important factors upon which its industrial applications depend. 

An electrochemical theory has been applied to explain the mechanisms of adsorption of metal ions on activated charcoal (carbon). According to this theory, oxygen in contact with an aqueous suspension of charcoal is reduced to hydroxyl groups with the liberation of hydrogen peroxide ... 

The study of metal ion/metal(s) interfaces has been limited because of the excessive adsorption of the reactants and impurities at the electrode surface and due to the inseparability of the faradaic and nonfaradaic impedances. For obtaining reproducible results with solid electrodes, the important factors to be considered are the fabrication, the smoothness of the surface (by polishing), and the pretreatment of the electrodes, the treatment of the solution with activated charcoal, the use of an inert atmosphere, and the constancy of the equilibrium potential for the duration of the experiment. It is appropriate to deal with some of these details from a practical point of view. 

For most uses, the Na2C03 must be purified. This is done by dissolving it in water and separating insoluble rocky material by filtration. Organic impurities are removed by adsorption using activated charcoal. The hydrated crystals of Na2C03-H20 are obtained by boiling off the excess water to concentrate the solution. The hydrated crystals are heated in a rotary kiln to obtain anhydrous sodium carbonate ... 

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