State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing, 100084, China.
State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; Vehicle Emission Control Center of Ministry of Ecology and Environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
Environ Pollut. 2024 May 1;348:123869. doi: 10.1016/j.envpol.2024.123869. Epub 2024 Mar 26.
The Chinese central government has initiated pilot projects to promote the adoption of gasoline containing 10%v ethanol (E10). Vehicle emissions using ethanol blended fuels require investigation to estimate the environmental impacts of the initiative. Five fuel formulations were created using two blending methods (splash blending and match blending) to evaluate the impacts of formulations on speciated volatile organic compounds (VOCs) from exhaust emissions. Seven in-use vehicles covering China 4 to China 6 emission standards were recruited. Vehicle tests were conducted using the Worldwide Harmonized Test Cycle (WLTC) in a temperature-controlled chamber at 23 °C and -7 °C. Splash blended E10 fuels led to significant reductions in VOC emissions by 12%-75%. E10 fuels had a better performance of reducing VOC emissions in older model vehicles than in newer model vehicles. These results suggested that E10 fuel could be an option to mitigate the VOC emissions. Although replacing methyl tert-butyl ether (MTBE) with ethanol in regular gasoline had no significant effects on VOC emissions, the replacement led to lower aromatic emissions by 40%-60%. Alkanes and aromatics dominated approximately 90% of VOC emissions for all vehicle-fuel combinations. Cold temperature increased VOC emissions significantly, by 3-26 folds for all vehicle/fuel combinations at -7 °C. Aromatic emissions were increased by cold temperature, from 2 to 26 mg/km at 23 °C to 33-238 mg/km at -7 °C. OVOC emissions were not significantly affected by E10 fuel or cold temperature. The ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) of splash blended E10 fuels decreased by up to 76% and 81%, respectively, compared with those of E0 fuels. The results are useful to update VOC emission profiles of Chinese vehicles using ethanol blended gasoline and under low-temperature conditions.
中国中央政府已启动试点项目，以推广使用 10%v 乙醇（E10）的汽油。需要对使用乙醇混合燃料的车辆排放进行调查，以评估该倡议的环境影响。使用两种混合方法（飞溅混合和匹配混合）创建了五种燃料配方，以评估配方对来自废气排放的特定挥发性有机化合物（VOC）的影响。招募了七辆涵盖中国 4 至 6 排放标准的在用车辆。使用全球协调测试周期（WLTC）在 23°C 和-7°C 的温度控制室内对车辆进行测试。飞溅混合的 E10 燃料可使 VOC 排放量减少 12%-75%。E10 燃料在较旧型号车辆中比在较新型号车辆中具有更好的降低 VOC 排放的性能。这些结果表明，E10 燃料可能是减轻 VOC 排放的一种选择。虽然用乙醇替代普通汽油中的甲基叔丁基醚（MTBE）对 VOC 排放没有显著影响，但替代导致芳烃排放减少 40%-60%。烷烃和芳烃占所有车辆-燃料组合 VOC 排放的约 90%。在所有车辆/燃料组合中，低温使 VOC 排放增加了 3-26 倍，在-7°C 时。芳烃排放随低温增加，从 23°C 时的 2-26mg/km 增加到-7°C 时的 33-238mg/km。O3 形成潜力（OFP）和二次有机气溶胶形成潜力（SOAFP）分别比 E0 燃料降低了 76%和 81%。这些结果对于更新使用乙醇混合汽油和在低温条件下的中国车辆的 VOC 排放特征很有用。
