Granulated activated charcoal

Vapor treatment equipment consisting of two serial filters containing 1000 lb of granulated activated charcoal (GAC) situated upstream of the SVE blower and... 

Weigh out 1 g of granulated activated charcoal into each of five clean, stoppered 250cm conical flasks. Add lOOcm of 0.2M acetic acid... 

Danneel2 used granulated, activated charcoal as a catalyst. The method of Danneel can be readily modified to permit the production of relatively large amounts of this very important reagent. 

Schramm and Primosigh use Schering s granulated active charcoal... 

Activated carbon or activated charcoal Carbon in the form of charcoal granules, which has an affinity to adsorb many gases and vapors and, in so doing, removes odors. It is manufactured by exposing coal, coconut shells, or peat to steam at 800 to 900 C. 

The carbon micronization system (CMS) is used for the disposal of agent-contaminated, activated charcoal that was used as an agent filtration medium in the pollution abatement system of the plant cascade ventilation system. CMS is a system that grinds the solid carbon granules into micronized particles so that the carbon can be thermally treated in its furnace. 

Kensler CJ, Battista SB. SP. 1963. Components of cigarette smoke with ciliary-depressant activity. Their selective removal by filters containing activated charcoal granules. N Engl J Med 269 1161-1166. 

Activated charcoal was originally regarded as a relatively inexpensive adsorbent with an assortment of pores of ill-defined size and shape. However, in recent years considerable progress has been made in the development of tailor-made porous carbons such as molecular sieves, activated carbon fibres and carbon composites (Marsh et al., 1997). Superactive carbons are now made on a commercial scale with BET areas of around 3000 m2g-1. Activated carbons can be manufactured as fine particles or granules or in the form of a cloth, felt or consolidated membrane. The properties of some of these special types of activated carbon are discussed in Chapter 12. 

Granulate catalyst—c.g., ion-exchange resins, precious metals on alumina, or activated charcoal supports—may be embedded between two corrugated permeable screens to form a sandwich, and the sandwiches in turn stacked such as to give the characteristic OCFS structure—Fig. 5. This variant is of particular interest for heterogeneous gas-liquid systems such as trickle beds and bubble columns—see Section IV—and catalytic distillation—see Section V. 

The 72 to 77% urea solutions obtained with these processes are, after prepurification e.g. over activated charcoal to remove oil, either vacuum evaporated until crystallization takes place or evaporated in a falling film evaporator to a urea melt (m.p. 132.7°C). These urea melts or molten crystals are generally prilled (however granulated urea is also produced). 

Chemistry Phosgene can be prepared in the laboratory using a reaction similar to its commercial synthesis. In this gas-phase process, equimolar amounts of chlorine and carbon monoxide are passed over a bed of activated charcoal granules. 

During recycling, odors are removed by filters containing activated charcoal granules, which absorb from the air the chemical substances that cause the odor. Carbon dioxide gas is removed from the air by reacting it with solid lithium hydroxide. 

The realization that it was more economical to have a single respirator design for all three services led to the introduction of the General Service (GS) respirator, familiar to all those who served in the Second World War. Over 25 million of these respirators were made in the UK alone, and issued to all Commonwealth forces and Civil Defence Corps. The GS respirator consisted of a rubber facepiece with stockinette covering, flat circular eyepieces, a diver-type outlet valve, an elastic webbing harness and a filter canister fitted with an inlet valve. The canister, worn on the body and attached to the facepiece by a hose, was filled with activated charcoal granules, with a wool-asbestos mixture added later, and impregnated charcoal added even later. 

If chlorine and acetylene (molar ratio 2 1) are led over iron granules at 60°, 1,1,2,2-tetra-chloroethane is formed almost quantitatively.1 d Use of an excess of acetylene and active charcoal at 40-50° leads to a product composed of c/s-l,2-dichloroethylene 90% and 1,1,2,2-tetrachloroethane 10%.ld 97% of /ra s-l,2-dichloroethylene is obtained if acetylene is led into a solution of CuCl2 and Cu2Cl2 in 20% hydrochloric acid at 85°/250 mm.93... 

Collection efficiency for radioiodine from the air stream by activated charcoal is subject to type of charcoal, size of the granules, depth of the sampling bed, and flow rate. The grain size should be in the range 12-30 mesh and the sampling rate, 0.03-0.09 m m for optimum collection (APHA 1972.). Air streams can also be monitored for radioiodine with silver zeolite and molecular sieve, but activated charcoal is the commonly used sorbent largely due to lower cost. 

Rebouillat el al [4] and Suzuki [5] give good reviews of activated carbon fibers. Traditionally, activated carbon granules are made by the carbonization of a product such as coconut shells, which due to their physical granular form, tend to be difficult to handle and the development of an activated woven cloth by the British Chemical Defence Establishment at Porton Down [6,7] via the controlled heat treatment of a woven rayon cloth offers many advantages. The activated charcoal cloth (ACC) product was made under licence in 1977, by Charcoal Cloth Ltd. One such process used a 1.8 m wide fabric, reducing to about 1.0 m at the end of the process. To aid carbonization, the cloth was treated with a solution of chemicals to confer a measure of flame retardancy. As explained in Chapter 6, there are two forms of flame retardant—one where the flame retardant acts as a catalyst and promotes removal of the —OH groups and the other form, which actually reacts with the —OH... 

In using charcoal tubes filled with activated charcoal granules, some figure work is needed if time is not to be wasted going back for a second try. An educated guess at the concentration is needed (perhaps from your detector tube results). You should consult a tube manufacturer s sheet to ensure the chemical you are collecting can ... 

The adsorbers are usually built of steel, and may be lagged or left unlagged the horizontal type is shown in Figure 28. The vapor-laden air is fed by the blower into one adsorber which contains a bed of 6- to 8-mesh activated carbon granules 12 to 30 inches thick. The air velocity through the bed is 40 to 90 feet per minute. The carbon particles retain the vapor only the denuded air reaches the exit, and then the exhaust line. The adsorption is allowed to continue until the carbon is saturated, when the vapor-laden air is diverted to the second adsorber, while the first adsorber receives low-pressure steam fed in below the carbon bed. The vapor is reformed and carried out by the steam. The two are condensed and if the solvent is not miscible with water, it may be decanted continuously while the water is run off similarly. After a period which may be approximately 30 or 60 minutes, all the vapor has been removed, the adsorbing power of the charcoal has been restored, and the adsorber is ready to function again, while adsorber No. 2 is steamed in turn. 

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