2,6-Naphthalenedicarboxylic Acid Preparation Of2-Methy Naphthalene Acylation And Oxidation Reaction

As we known, there is abundant coal resource in our country. Nowadays, with theenergy resource becoming more and more constrictive, developing a naphthalene valueincreasing route is thereby becoming increasingly significant as a measure to thereasonable utilization of coal and heavy constituent2,6-Naphthalenedicarboxylicacid(2,6-NDA)is an important monomer for making high-quality polymers, and also couldbe used as an intermediate. Particularly, polyethylene naphthalene (PEN) formed from2,6-NDA and ethylene glycol has higher physical and chemical properties thanpolyethylene terephthalate (PET) which has been widely used, and is useful for productionof fiber, film, container, electrical applications. It has been commercialized in somedeveloped countries. such as Japan and American, but only a little research has been donein china, and up to date, no appropriate technology route is available for synthesis of2,6-NDA in large scale.The main contents in this paper are studied as follows. First,2-methyl-6-propionylnaphthalene was synthesized in a liquid phase system from2-methylnaphthalene with nitrobenzene as solvent and aluminium chloride、ferric chloride and zincchloride、 Triethylamine Hydrochloride-ferric chloride Ionic Liquid、N-methylimidazole-aluminium chloride Ionic Liquid as catalyst. According to theexperimental results, the best acidylate condition reasons is obtained at reactiontemperature25℃、and the reaction time5hours. And the yield of production is84%,andthe purity is96%by GC in this condition., it can obtain the purity above98%using there-crystallization purification using methanol solution of the crude product and the yield ofproduction is87%.It can be used for the oxidation reaction to prepare2,6-naphthalenedicarboxylic acid, The product structure is itenified by FT-IR and MS.Secondly, In Co-Mn-Br catalytic system,for2-methyl-6-the naphthalene propionyl the air liquid phase oxidation reaction and the oxidation reaction conditions were2,6-MPNoxidation reaction was carefully discussed. According to the experimental results, thebest operating conditions are the air flowing3L/min, reaction time30min, reactionpressure2.2MPa, and reaction temperature190℃. Theoxidation products yield is71.7%and the purity is98.6%under this operating conditions. Finally, the lose of aceticand catalytic mechanism of Co-Mn-Br catalyst are discussed.