Sources of Waste from the Chemical Industry

There are several ways to look at this data. For example, oil refining can be viewed as being fairly clean, with an E-factor of less than 10%. On the other hand it could be viewed as being highly polluting if the total amount 

Industry segment Annual production (t) E-factor Total waste (t approx.) 

Data taken from R. A. Sheldon, Chem. Ind. 1 December 1992, p. 904. 

As demand for phenol started to grow owing to the increased use of phenolie resins and the advent of polycarbonates, more eompanies looked for proeess improvements which gave economie benefits. Although avoidanee of waste was not a prime target it became a faetor in the overall production costs. With the discovery of the cumene route (Seheme 2.3) for the co-production of phenol and acetone (propanone), the benzene sulfonation route quickly became obsolete in developed countries. Today the most modem phenol plants produce very little waste, the initial alkylation step being carried out using zeolite eatalysts, and overall yields based on benzene are almost 90%. 

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