Petroleum comes from Latin and means "rock oil". Petrochemical plants continue the process started in the distillation towers and are often located at the same location or near refineries. When people talk about petrochemicals they’re usually referring to a group of chemicals manufactured using crude petroleum and natural gas feedstocks as raw materials. Petrochemicals are the building blocks for production of thermoplastic and thermosetting materials. Thermoplastics are materials that can be softened over and over by heating them up above their melting temperature. (The opposite of this is thermosets, which once formed can only be destroyed buy burning). The most important thermoplastics are high and low density polyethylene (HDPE and LDPE), polypropylene (PP), polyvinyl chloride (PVC), and polystyrene (PS).
In an earlier blog post we mentioned three common ways gasses are processed after leaving the distillation tower. Thermoplastics are produced by applying one of three methods to the products that came from the refinery. These methods include cracking, further refining, and polymerization. We’ll be looking at each one of these in in future posts.
Photo from www.chem.agilent.com