PDO is an important chemical raw material, widely used in polyester, polyurethane, cosmetics, biodegradable plastics, pharmaceutical intermediates, inks, printing and dyeing, lubricants and other fields. The main use of PDO is to polymerize with terephthalic acid (PTA) to produce polytrimethylene terephthalate (PTT).
PTT is a new type of high-performance bio-based polyester fiber: in terms of physical properties, it has the stability of PET, the softness of nylon, the fluffiness of acrylic, the anti-fouling of polyester, and the elastic recovery ability close to spandex, and has excellent shape retention characteristics, also known as "memory fiber"; in terms of chemical properties, PTT is UV-resistant, chloride-resistant, and suitable for low-temperature dyeing. PTT has multiple excellent properties at the same time and was named "the king of polyester" as early as the last century.
Traditional polyester production technology is mature, market competition is fierce, and profit margins are extremely low. Many polyester manufacturers have to actively develop new products and find profit growth points. PTT is an excellent choice to replace (partially replace) traditional chemical fibers such as PET, PBT, PA6, and spandex.
It is understood that there are three types of PDO production processes in the world, namely: the acrolein hydration hydrogenation method of Degussa in Germany, the ethylene oxide carbonylation method of Shell in the United States, and the bio-based sugar method of DuPont in the United States. The first two are petrochemical-based routes, and they have withdrawn from the market due to large investments, high technical difficulties, and high costs. After 2013, the glycerol bio-based process independently developed by Professor Liu Dehua's team at Tsinghua University was put into production. In 2022, Huafeng Group acquired DuPont's 1,3-propylene glycol-related patents and businesses, and the production of PDO has gradually concentrated in China. At present, it is basically a biological process, and the production method presents a situation where glycerol fermentation and glucose conversion coexist.
