Primary processing, noncatalytic

Chlorination of Ethylene Dichloride. Tetrachloroethylene and trichloroethylene can be produced by the noncatalytic chlorination of ethylene dichloride [107-06-2] (EDC) or other two-carbon (C2) chlorinated hydrocarbons. This process is advantageous when there is a feedstock source of mixed C2 chlorinated hydrocarbons from other processes and an outlet for the by-product HCl stream. Product ratios of tri- and tetrachloroethylene are controlled by adjusting the CI2 type="subscript">2 EDC ratio to the reactor. Partially chlorinated by-products are recycled to the chlorinator. The primary reactions are... 

With the balance for the number of available forms of active centers of a catalyst, the concentrations and, correspondingly, the thermodynamic mshes of the reaction complexes catalytic intermediates)—that is, the thermalized intermediate compounds of the reactant molecule (or molecular fragment) with the active center—appear interrelated through these balance relations in respect of each type of active center. The balance is of primary importance to the kinetics of the stepwise transformations and causes a number ofpecuHarities of the stationary kinetics of the stepwise processes. This makes the kinetic description of the catalytic transformations differ considerably from the descrip tion of the preceding schemes of noncatalytic reactions. For example, in the simplest catalytic stepwise transformation of substance R to substance P,... 

This section provides brief descriptions of industrial processes in which noncatalytic gas-solid reactions play a major role. Although by no means complete, the discussion includes both traditional processes, such as the blast furnace for the production of iron from ore and the regeneration of fluidized-bed catalytic cracking catalyst, and newer processes such as the dry capture of SO2 from flue gas and the production of silicon for semiconductor applications. Each of the three primary reactor types is represented in the processes described. 

Fixed beds, also called packed beds, play a vital role in chemical processes. Their simplicity induced applications in many unit operations such as adsorption, drying, filtration, dust collection, and other catalytic and noncatalytic reactors. The primary operating cost for a fixed bed is the pressure drop through the packed bed of solids. Thus to understand the design and operation of a packed bed requires study of packing characteristics of particles and their effect on pressure drop through the bed. 

Catalytic pyrolysis using an ex situ process mode usually occurs in multiple reactors. Pyrolysis vapors are created in a primary (noncatalytic) reactor and are... 

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