PTA (Pure Terephthalic Acid)
Njira yopanga mankhwala
PTA ndiye mapeto apansi a petroleum.Petroleum imapanga njira inayake kuti ipange naphtha (yomwe imadziwikanso kuti mafuta opepuka), momwe MX (yosakaniza xylene) imachotsedwa, ndiyeno PX (paraxylene) imachotsedwa.PTA imagwiritsa ntchito PX ngati zopangira ndi acetic acid monga zosungunulira, ndipo imapangidwa ndi okosijeni ndi mpweya pansi pa chothandizira kupanga terephthalic acid.Ndiye yaiwisi asidi terephthalic ndi hydrorefined kuchotsa zosafunika, ndiyeno crystallized, olekanitsidwa, zouma ndi anakonza woyengeka terephthalic asidi mankhwala, ndiye PTA anamaliza mankhwala.
Chiyambi cha malonda
PTA ndi kristalo woyera kapena ufa pa kutentha kwa chipinda, kawopsedwe kakang'ono komanso kuyaka.poyatsira malo ake ndi 384 ~ 421 °C, sublimation kutentha 98.4kJ/mol, kuyaka kutentha 3225.9kJ/mol, ndi kachulukidwe 1.55g/cm3.Amasungunuka mu njira ya alkali, sungunuka pang'ono mu ethanol wotentha, wosasungunuka m'madzi, ether, glacial acetic acid ndi chloroform.
Kugwiritsa ntchito mankhwala
Zida zofunika popanga ulusi wa poliyesitala, mafilimu, zinthu zapulasitiki, utoto wotsekereza ndi mapulasitiki, ndipo amagwiritsidwanso ntchito ngati zopangira utoto.
PTA ndi imodzi mwazinthu zofunika kwambiri zopangira organic, zomwe zimagwiritsidwa ntchito kwambiri muzamankhwala, mafakitale opepuka, zamagetsi, zomanga ndi zina pazachuma cha dziko.
Kugwiritsa ntchito kwa PTA kumakhala kokhazikika, kuposa 90% ya PTA yapadziko lonse lapansi imagwiritsidwa ntchito popanga polyethylene terephthalate (yotchedwa polyester, PET).Kuti apange tani imodzi ya PET, matani 0.85-0.86 a PTA ndi matani 0.33-0.34 a MEG (ethylene glycol) amafunikira.Polyester imaphatikizapo tchipisi cha fiber, ulusi wa poliyesitala, tchipisi tabotolo ndi tchipisi tamafilimu.Ku China, 75% ya PTA imagwiritsidwa ntchito popanga ulusi wa polyester;20% imagwiritsidwa ntchito popanga utomoni wa botolo la PET, womwe umagwiritsidwa ntchito kwambiri popaka zakumwa zosiyanasiyana, makamaka zakumwa za carbonated;5% ya poliyesitala ya kalasi yamakanema, yomwe imagwiritsidwa ntchito makamaka pakuyika zida, makanema ndi matepi.Chifukwa chake, zinthu zakumunsi za PTA zimakhala makamaka ulusi wa poliyesitala.
