Raw Materials, Manufacturing, and Engineering

Industrial chemistry procures raw materials from natural environments to convert them into intermediates, which subsequently serve as base materials to every other kind of industry. There are four sources of natural environment  

Raw materials derived from the above natural resources are classified as either renewable or nonrenewable. Renewable resources are those that regenerate themselves, such as agricultvmal, forestry, fishery, and wildlife products. If the rate at which they are consumed becomes so great that it drives these resources to exhaustion, however, these renewable resources can become nonrenewable. Nonrenewable resovurces are those that are formed over long periods of geologic time. They include metals, minerals, and organic materials. 

As illustrated in Fig. 1.1, the organic chemical industry requires raw materials from renewable or nonrenewable resources, and sells its products either as finished materials or as intermediates for further processing by other manufacturers. The two major steps in chemical manufacturing are (1) the chemical reaction and (2) the purification of reaction products [7]. 

The primary types of chemical reactions are either batch or continuous. In batch reactions, the reactant chemicals are added to the reactor (reaction vessel) at the same time and products are emptied completely when the reaction is finished. The reactors are made of stainless steel or glass-lined carbon steel and range in size from 200 to several thousand liters. Batch reactors are provided with a stirrer to mix the reactants, an insulating jacket, and the appropriate pipes and valves to control the reaction conditions.  

Batch processes generally are used for small-scale production. These processes are easier to operate, maintain, and repair. The batch equipment can be adapted to multiple uses. 

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