| Methyl tert-butyl ether is a widely used gasoline additive. Its presence in the environment causes a widespread pollution and poses a serious threat to human health. This experiment studied volatilization, photolysis and hydrolyzation of MTBE in surface water. In the same time, the situation of the pollution of MTBE in surface water of Changchun city was researched. The study on the field in china is important and necessary.1. MTBE in water was distilled by headspace analytical method. The main factor that influenced the sensitivity of the method was the headspace thermostat temperature and time and the salting-out. The result expressed: increasing the temperature could increase the sensitivity, but if the temperature was too high, the analytical accuracy would decrease. The research showed that when the temperature was 90℃,the sensitivity was high, and the accuracy could match the analytic request. This experiment detected MTBE at different interval, and found that the result of detection didn't change after 30 min. 30 min was the equilibrium time. By adding different kind of strong electrolyte to the sample aqua, the sensitivity didn't increase. The salting-out had no affect of this method.2. The sample was detected by Agilent 6890N/FID GC, the DB-MTBE capillary column was used to separate the samples. Absorbing 500uL gas from headspace bottle by hermetic syringe, and injected into GC. The station of GC was as follows:The procedure heats mode: 35℃ (5min) 15℃/min to 120℃ (2min) ;FID:250℃;H2 flow velocity: 40-45mL/min;Air flow velocity: 400ml/min.This method was single, and easy to operate, the detected limit was 0.2443ug/L.The recovery ratio was measured by Standard affiliation method to investigate the accuracy of the method. The adding level was 0.74~370.0ug/L, and the average recovery ratio was 89.4-100.3 %.The minimum detectable quantity was 2.02×10-12g.The linear range was 0.740 ~ 37.0u,g/L and 0.074 ~ 7.40mg/L.The relative standard deviation was 1.46-5.52%.3. The result of hydrolyzation showed that the hydrolyzation process of MTBE in water accorded with the first order reaction kinetics model C=C0e-kt.When the temperature was 25℃, the hydrolyzation half-life of MTBE was 69.59,81.26 and 165.8d respectively when the pH was 3.29, 7.24 and 9.15. So in the same temperature, MTBE hydrolyzed faster when water was acidic. The hydrolyzation half-life of MTBE was longer than 69d according to the result above. That was decided by the molecule structure of MTBE, there was ether functions regiment in its structure. The activation energy was 76.2, 74.1 and 72.0kJ/mol respectively when pH was 3.29, 7.24 and 9.15. This indicated that the same reaction had happened under different pH.4. The result of imitating the water experiment showed that the disappearing process of MTBE in water accorded with the first order reaction kinetics model: C=C0e-kt. The result of indoors experiment showed that the disappearance half-life of MTBE was from 25.1to86.5d, this implied MTBE is stable in environment. With improving of the temperature, the MTBE disappearing velocity became faster.5. When irradiated by high voltage mercury light whose wave length was 365nm, the photolysis half-life was 54.6h.The photolysis process of MTBE in water accorded with the first order reaction kinetics model C=C0e-kt.6. The result of volatilization of MTBE in water showed that the volatilization process accorded with the first order reaction kinetics model C=C0e-kt. The Henry laws constant was 112Pam3/mol at 20C, the volatilization half life was 6.8h. The volatilization velocity increased along with the increase of temperature.7. The research of MTBE in surface water of Changchun city showed that there was MTBE pollution of different degree to surface water. The investigation range was eight districts in Changchun city. The gas stations, the neighborhood of these gas stations, the parks, the wash car fields, the crossing and resident areas were chosen to collect water samples, there were 82 monitoring points in total. The sur...
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