Carbon-in-pulp process

Figure 5.41 Standard cyanide process Figure 5.42 Carbon-in-pulp process,...

S. M. Bradshaw, E. J. VanWyk and J. B. deSwardt, Preliminary economic assessment of microwave regeneration of activated carbon for the carbon in pulp process. Journal of Microwave Power and Electromagnetic Energy, 32, 131-144 (1997). 

FIGURE 9,2-3 Carbon-in-pulp process For recovery or gold at Homestake Mining Company. (Reproduced from McQuislon and Shoemaker,")... 

CIP (1) [Carbon In Pulp] A general name for hydrometallurgical extraction processes that use activated carbon in slurries of ground ores. One such process is used for extracting gold from cyanide leach liquors. First operated on a large scale at the Homestake lead mine in South Dakota in 1974. See also RIP. 

T0465 Klohn-Crippen Consultants, Ltd., ChemTech Soil Treatment Process T0469 Kvaemer Metals, Resin-in-Pulp/Carbon-in-Pulp... 

The Resin-in-Pulp (RIP) and Carbon-in-Pulp (CIP) processes were developed for the ex situ treatment of soils, sediments, dredgings, and soUd residues that are contaminated with organic... 

Fig. 21.12. Uranium ore mill processes (A) carbonate leach, caustic precipitation process (B) acid leach, ion exchange and acid leach, solvent extraction processes (C) acid leach, resin-in-pulp process.

The rewards for being able to understand and control the process of carbonization to give a particular pore structure are potentially enormous, with applications which include catalysis, carbon-in-pulp metal adsorption and separation processing, molecular sieves and bioethical applications. 

FIGURE 13.3-9 Slined-tank reain-in-pulp process similar technology is used for adsorption with activated carbon. 

Mixers are used in the gold leaching processes. Special tanks for carbon in pulp (CIP) or carbon in leach (CIL) are built with mixers. The largest diameter of these tanks is approximately 17 m (56 ft). 

A special type of process used to extract gold is based on cyanide leaching. Leached gold is then separated by adsorption, the property of certain materials such as carbon to fix gold on their surface. Carbon spheres are used as an adsorption material. This process is done in special carbon in leach or carbon in pulp circuits with mixing tanks. The transfer of these solutions requires recessed or vortex impellers that can pump without breaking the carbon lumps. The impeller is recessed out of the flow as shown in Figure 8-41. 

Substitution Reactions on Side Chains. Because the benzyl carbon is the most reactive site on the propanoid side chain, many substitution reactions occur at this position. Typically, substitution reactions occur by attack of a nucleophilic reagent on a benzyl carbon present in the form of a carbonium ion or a methine group in a quinonemethide stmeture. In a reversal of the ether cleavage reactions described, benzyl alcohols and ethers may be transformed to alkyl or aryl ethers by acid-catalyzed etherifications or transetherifications with alcohol or phenol. The conversion of a benzyl alcohol or ether to a sulfonic acid group is among the most important side chain modification reactions because it is essential to the solubilization of lignin in the sulfite pulping process (17). 

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