Na^+对PTA生产工艺及产品质量的影响  

Effect of Na^+ on PTA production process and product quality

作　　者：薛月霞[1] 苟占红[1] 李顶松[1] 

机构地区：[1]中国石化仪征化纤股份有限公司,江苏仪征211900

出　　处：《合成纤维工业》2015年第6期70-73,共4页China Synthetic Fiber Industry

摘　　要：采用对二甲苯(PX)高温氧化法生产精对苯二甲酸(PTA),以氢氧化钠(Na OH)为辅料进行防腐和除杂,探讨了Na+对PTA的生产工艺及其产品质量的影响。结果表明:PX氧化反应进料中存在一定含量的Na+有利于PX氧化主反应,过量的Na+会抑制主反应,并使副反应加剧,导致粗对苯二甲酸(TA)的光密度(OD)值增加,从而影响PTA产品的质量;对于反应温度191℃、反应压力1.25 MPa的Amoco工艺,进料反应器中较佳的Na+含量为110~170 mg/kg;对于反应温度195℃、反应压力1.35 MPa的Invista工艺,进料反应器中较佳的Na+含量为100~150 mg/kg;Na+对加氢还原反应没有明显的促进或抑制作用,但TA中的Na+含量升高,会导致PTA灰分超标,可通过调整精制单元的工艺条件,洗涤除去Na+,从而保证PTA产品的质量。The effect of Na＋ on the production process and product quality of purified terephthalic acid （PTA）, prepared from p -xylene （PX） by high-temperature oxidation, was discussed by using sodium hydroxide （NaOH） as auxiliary material for the purpose of antieorrosion and impurity removal. The results showed that a certain amount of Na＋ in the feedstocks would help the main oxidation reaction of PX, but an excessive amount of Na＋ would inhibit the main reaction and intensify the side reaction, which caused the optical density （ OD ） value of crude terephthalic acid （TA） to increase and thus damaged the PTA quality; the Na＋ content in the feeding reactor should properly be 110 - 170 mg/kg and 100 - 150 mg,/kg, respectively, for Amoco process at 191 ℃ and 1.25 MPa and Invista process at 195 ℃ and 1.35 MPa; Na＋ was found to have no obvious promotion or inhibition effect to hydrogenation reduction, but the increase of Na＋ content in TA would cause the ash content of PTA over the standard; and the PTA quality could be guaranteed by adjusting the purification process conditions to wash off Na＋.

关 键 词：精对苯二甲酸 对苯二甲酸 对二甲苯 氢氧化钠 高温氧化法 产品质量 

分 类 号：TQ245.12[化学工程—有机化工]