**2. The properties of DMC**

The vapor pressure data of DMC

The vapor pressure of DMC has been measured by Rodriguez3. The data of the experiment of DMC has been showed in table 3, which could be regressed by the extended Antoine equation.

property DMC phosgene DMS oral acute toxicity (rats) LD50 13.8 g/kg LD50 440 mg/kg

> LC50 140 mg/L; (4 h) LC50 16 mg/m3; (75 min)

> 90%(28 days) rapid hydrolysis rapid hydrolysis

NOECa 1000 mg/L LC50 10-100 mg/L (96

h)

mutagenic properties none mutagenic

none corrosive

Table 1. Comparison between the Toxicological and Ecotoxicological Properties of DMC,

azeotropical mixtures with water, alcohols, hydrocarbons

reaction conditions and low investment for equipment. As a result, the separation of the reacted mixture which contain an azeotropic mixture of DMC and methanol became very

The vapor pressure of DMC has been measured by Rodriguez3. The data of the experiment of DMC has been showed in table 3, which could be regressed by the extended Antoine

Table 2. Some Physical and Thermodynamic Properties of DMC1

LC50 1.5 mg/L (4 h)

LD50 > 2.5 g/kg

EC50 > 1000 mg/L

a NOEC=Concentration which does not produce any effect.

mp (°C) 4.6 bp (°C) 90.3 density (D204) 1.07 viscosity (μ20, cps) 0.625 flashing point (°C) 21.7 dielectric constant (ε25) 3.087 dipole moment (μ, D) 0.91 △Hvap (kcal/kg) 88.2 solubility H2O (g/100 g) 13.9

important for the production of DMC.

**2. The properties of DMC**  The vapor pressure data of DMC

equation.

acute toxicity per contact

acute toxicity per inhalation (rats)

irritating properties (rabbits, eyes, skin)

biodegradability (OECD

acute toxicity (fish) (OECD

acute toxicity on aerobial bacteria of wastewaters

Phosgene, and DMS1

(cavy)

301 C)

203)

(OECD 209)


Table 3. Experimental vapor pressure and boiling point for DMC

The Design and Simulation of the Synthesis of

Dimethyl Carbonate and the Product Separation Process Plant 65

T (K) x y γ1 γ2 340.11 0.4247 0.6960 1.502 1.165 339.18 0.4916 0.7206 1.390 1.256 338.69 0.5386 0.7394 1.325 1.316 338.21 0.5800 0.7547 1.279 1.386 337.55 0.6622 0.7806 1.187 1.582 337.18 0.7181 0.7955 1.131 1.794 336.97 0.7684 0.8123 1.088 2.022 336.95 0.8160 0.8332 1.051 2.265 336.88 0.8617 0.8560 1.025 2.612 336.89 0.8824 0.8736 1.021 2.698 336.98 0.9104 0.8931 1.008 2.988 337.11 0.9341 0.9166 1.003 3.158 337.25 0.9549 0.9406 1.002 3.273 337.39 0.9726 0.9614 1.000 3.487 337.60 0.9889 0.9833 0.998 3.699

Table 4. Vapour–liquid equilibrium data for methanol (1) +DMC (2) system at 101.3 kPa4

and DMC would be difficult with the normal distillation.

system at different temperatures from different literature.

**3.2 The VLE for DMC with other compound** 

*T* (K) *x y*

The azeotrope data for methanol-DMC on the high pressure has been show on the following table, which was a comparison of the data from different literature. The data has exhibited the composition of DMC in an azeotrope of DMC-methanol decreased with the increases of pressure. These thermodynamic data showed that the separation of the mixture of methanol

T (K) p (kPa) x1 w1 p(kPa) x1 w1 337.35 102.73 0.8500 0.6684 101.33 0.8677 0.7000 377.15 405.70 0.9100 0.7824 405.2 0.9150 0.7929 391.15 613.00 0.9150 0.7929 607.8 0.9298 0.8249 411.15 1077.00 0.9200 0.8036 1013.0 0.9521 0.8761 428.15 1576.00 0.9625 0.9013 1519.5 0.9739 0.9300

Table 5. Comparisons of azeotrope data for methanol (1)–dimethyl carbonate (2) binary

362.37 0.0180 0.0494 1.853 0.992 361.70 0.0293 0.0790 1.864 0.993 361.00 0.0394 0.1044 1.877 0.997

γ1 γ2
