It is known that the transport sector has a fundamental importance in the modem society, as the economic development is directly linked to mobility. Over the years, the transport became linked to different environment...It is known that the transport sector has a fundamental importance in the modem society, as the economic development is directly linked to mobility. Over the years, the transport became linked to different environmental problems, which can be detached greenhouse gases emissions in the atmosphere, where in recent decades can be perceived the intensification and targeting of efforts in research and development of new technologies to reduce the levels of greenhouse gases emissions in the atmosphere. In this context, it can be highlighted the modem systems of electronic engine management, new automotive catalysts and the use of renewable fuels which contribute to reducing the environmental impact. This research had, as its purpose, the analysis of fuels characteristics used for testing, comparative analysis of gas emissions from a motor vehicle running on ethanol or natural gas fuels according to NBR 6601 and conducting tests to estimate the maximum catalytic efficiency. For the implementation of trial, a flex vehicle was installed in a chassis dynamometer equipped with a gas analyzer, in order that before the completion of the urban driving cycle, were determined the content of hydrocarbons corrected, carbon monoxide corrected, carbon dioxide and oxygen present in gas emissions from the engine. The research concluded that: the performance analysis for characterization of fuel showed consistent with ANP specifications; after tests performances, it can be stated that natural gas fuel was the fuel which had the highest content of hydrocarbons and carbon monoxide corrected, while ethanol had the highest amount of carbon dioxide and oxygen residue present in gas emissions; before a comparative analysis, the vehicle catalyst showed the best performance for reducing the content of hydrocarbon corrected present in exhaustion gases when it worked with natural gas fuel and showed maximum efficiency of 100% to reduce the content of carbon monoxide corrected for both fuels. Before this, it can be stated that the vehicle catalyst showed satisfactory performance, achieving good reduction levels of greenhouse gases emissions.展开更多
Modification and characterization of natural zeolite under some various methods for hydrocracking catalyst of waste lubricant to gasoline and diesel fractions have been conducted. Natural zeolite from Klaten was activ...Modification and characterization of natural zeolite under some various methods for hydrocracking catalyst of waste lubricant to gasoline and diesel fractions have been conducted. Natural zeolite from Klaten was activated using hydrothermal treatment at temperature 500 ℃ for 6 h (produced ZAAHd), the ZA sample was treated with hydrothermal followed by Microwave (produced ZAAHdM), the ZA sample was treated with HCI 3 N at temperature of 90 ℃ for 30 min (produced ZAAH), the ZAAH sample was heated in to microwave (produced ZAAHM), the ZAAHM was treated hydrothermal (produced ZAAHMHd), the ZAAHMHd sample was heated in to microwave (produced ZAAHMHdM), soaking of natural zeolit activated by HCl-microwave-hydrothermal-microwave in NH4NO3 1 N which was stirred using stirer at room temperature for 24 h (produced ZAAHMHdMN) and the ZAAHMHdMN sample was heated into microwave (ZAAHMHdMNM). The heating process by microwave was conducted at 550 watt for 15 rain. Catalyst characterization involved determination of the number of total acid sites using gravimetric method with vapour adsorption of NH3 and pyridine, catalyst crystallinity by XRD (X-ray diffraction) and TO4 (T= Si and AI) site by infra red spectrophotometer (IR). Hydrocracking of waste lubricants oil was performed in a fixed bed reactor of stainless steel at temperature of 450 ℃, H2 flow rate of 15 mL/min., feed/catalyst ratio of 5. Liquid products of the hydrocracking were analyzed using GC (gas chromatography). The characterization results showed that various modification of natural zeolite increased acidity and dealumination degree of the catalysts. Products of the hydrocracking were liquid, coke, and gas fractions. Liquid products consisted of gasoline fraction (C5-C12), diesel fraction (C12-C20), and heavy oil fraction (〉 C20).Thc conversion of liquid products was increased with the increase of catalyst acidity. The greatest liquid product conversion was produced by the ZAAHMHdMNM catalyst, i.e., 56.80%, with selectivity towards gasoline, diesel, and heavy oil fractions was 88.37%, 8.61% and 3.02%, respectively. The increase of catalyst acidity increased the selectivity of gasoline fraction.展开更多
文摘It is known that the transport sector has a fundamental importance in the modem society, as the economic development is directly linked to mobility. Over the years, the transport became linked to different environmental problems, which can be detached greenhouse gases emissions in the atmosphere, where in recent decades can be perceived the intensification and targeting of efforts in research and development of new technologies to reduce the levels of greenhouse gases emissions in the atmosphere. In this context, it can be highlighted the modem systems of electronic engine management, new automotive catalysts and the use of renewable fuels which contribute to reducing the environmental impact. This research had, as its purpose, the analysis of fuels characteristics used for testing, comparative analysis of gas emissions from a motor vehicle running on ethanol or natural gas fuels according to NBR 6601 and conducting tests to estimate the maximum catalytic efficiency. For the implementation of trial, a flex vehicle was installed in a chassis dynamometer equipped with a gas analyzer, in order that before the completion of the urban driving cycle, were determined the content of hydrocarbons corrected, carbon monoxide corrected, carbon dioxide and oxygen present in gas emissions from the engine. The research concluded that: the performance analysis for characterization of fuel showed consistent with ANP specifications; after tests performances, it can be stated that natural gas fuel was the fuel which had the highest content of hydrocarbons and carbon monoxide corrected, while ethanol had the highest amount of carbon dioxide and oxygen residue present in gas emissions; before a comparative analysis, the vehicle catalyst showed the best performance for reducing the content of hydrocarbon corrected present in exhaustion gases when it worked with natural gas fuel and showed maximum efficiency of 100% to reduce the content of carbon monoxide corrected for both fuels. Before this, it can be stated that the vehicle catalyst showed satisfactory performance, achieving good reduction levels of greenhouse gases emissions.
文摘Modification and characterization of natural zeolite under some various methods for hydrocracking catalyst of waste lubricant to gasoline and diesel fractions have been conducted. Natural zeolite from Klaten was activated using hydrothermal treatment at temperature 500 ℃ for 6 h (produced ZAAHd), the ZA sample was treated with hydrothermal followed by Microwave (produced ZAAHdM), the ZA sample was treated with HCI 3 N at temperature of 90 ℃ for 30 min (produced ZAAH), the ZAAH sample was heated in to microwave (produced ZAAHM), the ZAAHM was treated hydrothermal (produced ZAAHMHd), the ZAAHMHd sample was heated in to microwave (produced ZAAHMHdM), soaking of natural zeolit activated by HCl-microwave-hydrothermal-microwave in NH4NO3 1 N which was stirred using stirer at room temperature for 24 h (produced ZAAHMHdMN) and the ZAAHMHdMN sample was heated into microwave (ZAAHMHdMNM). The heating process by microwave was conducted at 550 watt for 15 rain. Catalyst characterization involved determination of the number of total acid sites using gravimetric method with vapour adsorption of NH3 and pyridine, catalyst crystallinity by XRD (X-ray diffraction) and TO4 (T= Si and AI) site by infra red spectrophotometer (IR). Hydrocracking of waste lubricants oil was performed in a fixed bed reactor of stainless steel at temperature of 450 ℃, H2 flow rate of 15 mL/min., feed/catalyst ratio of 5. Liquid products of the hydrocracking were analyzed using GC (gas chromatography). The characterization results showed that various modification of natural zeolite increased acidity and dealumination degree of the catalysts. Products of the hydrocracking were liquid, coke, and gas fractions. Liquid products consisted of gasoline fraction (C5-C12), diesel fraction (C12-C20), and heavy oil fraction (〉 C20).Thc conversion of liquid products was increased with the increase of catalyst acidity. The greatest liquid product conversion was produced by the ZAAHMHdMNM catalyst, i.e., 56.80%, with selectivity towards gasoline, diesel, and heavy oil fractions was 88.37%, 8.61% and 3.02%, respectively. The increase of catalyst acidity increased the selectivity of gasoline fraction.