This study elucidates the effect of biodiesel on the emission of carbonyl compounds generated from a diesel engine (generator), and the related biotoxicity characteristics. The Microtox test and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay were conducted to evaluate the acute toxicity and cytotoxicity, respectively, of gaseous extracts from diesel engine exhaust. The engine was tested using diesel fuel and biodiesel blends (10, 30, 50, 75, and 100% of biodiesel by volume). The operating conditions of the diesel engine were set as idling, 10, 33, and 55% loads. The regulated emissions of carbon monoxide (CO), nitrogen oxides (NO), and carbon dioxide (CO) were monitored. The carbonyl compounds in the exhaust were collected in 2,4-dinitrophenylhydrazine (2,4-DNPH) solution in an impinger and converted to corresponding hydrazone derivatives, which were then analyzed using high performance liquid chromatography (HPLC) with an ultraviolet (UV) detector. Analysis results indicate that the carbonyl compound emissions increased when the engine was run on biodiesels at all of the loadings; however, the total concentration of emitted carbonyls did not increase with the biodiesel content. The dominant carbonyls (formalde-hyde, acetaldehyde, acrolein, and acetone) accounted for 70 to 90% of all carbonyl emissions in the engine exhaust. The concentrations of CO and NO from B10 were quite similar to those from diesel. Finally, in the toxicity assessments, B10 had a higher acute toxicity and cytotoxicity than diesel, indicating that blending with biodiesel may have adverse health effects because of toxic gas emissions. At various engine loads, higher toxicities were associated with greater carbonyl emissions in diesel exhaust, but not in B10, indicating that the carbonyls may not be the major pollutants that induce the toxicity of emissions from biodiesel.
This study surveyed emissions from 2-and 4-stroke new and in-use motorcycles. Emission tests were carried out on a dynamometer following the designated test procedure of the Economic Commission for Europe (ECE). Samples were derived during various driving stages, which included idle, acceleration, 30 km/hr cruise, 50 km/hr cruise, and deceleration. All test motorcycles (10 new and 15 in-use) complied with Taiwan Environmental Protection Administration's Phase III Motorcycle Emission Standards. The dominant volatile organic carbon (VOC) species were isopentane (53 and 295 mg/km, 2-and 4-stroke, respectively), 2-methylpentane (75 and 83 mg/km), 3-methylpentane (34 and 66 mg/km), and toluene (30 and 100 mg/km). The VOC emission factors for the 2-/4-stroke motorcycles were 311/344 (new) and 1479/433 (inuse) mg/km, respectively. In addition, the dominant carbonyl species for the new and in-use motorcycles were formaldehyde (0.4 and 0.7 mg/km, respectively), acetaldehyde (0.6 and 1.2 mg/km), and acetone (0.5 and 0.7 mg/km). The carbonyl compound emission factors for the 2-and 4-stroke motorcycles were 3.2/3.1 (new) and 5.3/ 4.6 (in-use) mg/km, respectively. The ozone formation potentials, based on an ECE test cycle, show that the values from the in-use motorcycles were higher than those from the new motorcycles. The dominant VOC species for the ozone formation potential were propylene (65 and 502 mg-O 3 /km, respectively), isopentane (98 and 501 mg-O 3 /km), 2-methylpentane (152 and 167 mg-O 3 / km), 3-methylpentane (79 and 253 mg-O 3 /km), and toluene (127 and 398 mg-O 3 /km). Further, the dominant carbonyl species were formaldehyde (4.1 and 6.2 mg-O 3 / km, new and in-use, respectively) and acetaldehyde (4.8 and 9 mg-O 3 /km).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.