656 JOURNAL OF CHEMICAL RESEARCH 2011
passing through the cold trap with N, N-dimethylformamide (DMF)
as an absorbent. Experiments showed that the amount of reactants and
products entrained by CO2 was negligible. The liquid chemicals in
the reactor were extracted in situ by super-critical CO2 at 12 MPa.
Experiments showed that all the reactants and products were collected
in the cold trap, and about 80 g CO2 was required to extract all
liquid chemicals. The catalyst was left in the reactor, because it
was not soluble in super-critical CO2. The liquid mixture in the reactor
was analysed by gas chromatography (Agilent 4890D, Agilent
Technologies Inc.) with a FID detector.
This work is supported by National Natural Science Founda-
tion of China (21004021), the Fundamental Research Funds
for the central universities (WA1014007), the State Special
S&T Project on Treatment and Control of Water Pollution
2009ZX07318-006 and the National Key Technology R&D
Program 2009BAC57B04.
Fig. 2 The effect of the molar ratio of MeOH:PO on the yield of
DMC at 140 °C. Reaction conditions: the molar ratio of PO:CO2:
K2CO3 = 1:10:0.065; the amount of PO in the reactor is 5 mmol.
Received 5 August 2011; accepted 13 October 2011
Paper 1100831 doi: 10.3184/174751911X13192908398731
Published online: 22 November 2011
Experimental
References
K2CO3 and anhydrous methanol were produced by the Beijing
Chemical Reagent Factory (A. R. Grade). Propylene oxide was sup-
plied by the Shanghai Chemical Reagent Factory (A. R. Grade). CO2
(>99.95%) was purchased from the Beijing Analytical Instrument
Factory. Methanol was dried with 4 Å molecular sieves. All the other
chemicals were used without further purification.
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A stainless steel batch reactor of 17.4 mL was used. The main compo-
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