Designation, Synthesis And Catalytic Properties Of New Catalysts For Green-preparation Of Dimethyl Carbonate

Dimethyl carbonate (DMC) is an environmental benign chemical compound and unique intermediate with versatile chemical reactivity which may contribute to "Green Chemistry" replacing toxic or high waste technology. Furthermore, DMC has gained interest as dipolar aprotic solvent and as fuel additive improving the octane number and replacing more toxic or less biodegradab additives. Among several phosgene-free approaches for DMC production, the direct oxidative carbonylation of methanol with CO and O2in a liquid-phase slurry reactor has shown to be one of the most promising processes for the production of DMC.The catalyst CuCl is widely used for the liquid phase carbonylation of methanol to DMC. However, the application of CuCl is hindered by the shortcomings of low stability, strong corrosiveness, and difficult separation of reaction mixture. As a result, the improvement of catalytic performance becomes a hot research topic. We take account of the special crystalline structure and coordination property of metal complexes, We employed transition metal complexes as catalysts and systematically investigated their catalytic performance, which includes the preparation and characterization of complexes and so on.In the first part, relative literatures were reviewed. The potential development and requirements, the synthetic technology and the application of dimethyl carbonate (DMC) were summerized in this section. The reseach progresses of the catalytic synthesis of dimethyl carbonate (DMC) by oxidative carbonylation of methanol were discribed.The preparation of terpyridine ligands were described in the second part. Twelve intermediate and three terpyridine ligands with different structures were synthesized, and the structures of all the comounds were characterized by NMR.In the third part, the catalytic activities of different complexs were tested. The experimental methods to use Autoclave and GC were discribed, including the calculation approachs of the original data. The results of experiments were analyzed and discussied about the conversion rate of methanol, the selectivity of DMC as well as the corrosion rata of the catalysts. Under120℃,2.4MPa (Pco:Po2=2:1) with0.1mol/L catalyst in3hours, the conversion rate of methanol achieved23.84%, the selectivity of DMC up to98.90%, space-time yield up to1.85g.DMC/(g.cat.h), the corrosion rate was3.33g/(m2.h) for stainless steel Q235.