Published March 2014
para-Dichlorobenzene (PDCB) is a chlorinated aromatic monomer that finds use primarily as a comonomer feedstock with sodium sulfide for the production of polyphenylene sulfide (PPS) polymer. PPS is a fast-growing polymer used in a number of applications, including electrical and electronics, power plant filtration systems, appliances, and automobiles. Although the market demand for the family of aromatic and aliphatic chlorinated hydrocarbons (known generally as chlorinated solvents) has been decreasing in industrialized countries for the past twenty years due to environmental concerns with groundwater and soil contamination, para-dichlorobenzene demand has increased substantially due to its use in PPS.
Unfortunately, para-dichlorobenzene cannot be produced alone. When manufactured by reacting chlorine with benzene, other mono-, di-, and tri-chlorinated benzene by-products are produced. To assure economic viability, a plant producing para-dichlorobenzene needs to maximize para-dichlorobenzene selectivity, while also finding acceptable commercial outlets for by-products, establishing an economically viable slate of production.
Despite the permanent shutdown of many chlorinated solvent plants in industrialized countries due to reduced demand and low profitability, some industry leaders have found economical ways to modify existing plants and shift product slates. For example, the leading producer in Western Europe, Lanxess, continues to increase its capacity to produce para-dichlorobenzene. Lanxess recently added an additional crystallizer, increasing capacity for para-dichlorobenzene production.
This PEP review presents IHS's understanding of current manufacturing technology for para-dichlorobenzene, and its corresponding production economics. The process economics for chlorobenzenes production are not readily available elsewhere, because they are smaller-volume products. This report will benefit companies that are interested in understanding the economics of chlorobenzenes production, for the purpose of exploring production or the use of para-dichlorobenzene as a feedstock.