Search Results

Phosphorus levels in engine oil are assumed to be lower than other oils because they cause emission catalyst poisoning. It mainly originates from zinc dithiophosphate (ZnDTP), which is an essential additive for engine oils as an antiwear agent and antioxidant. The reduction of ZnDTP in engine oils will have a great influence on this. On the other hand, fuel efficiency in vehicles is also an important issue and molybdenum dithiocarbamate (MoDTC) is very effective in improving fuel economy. Oils containing MoDTC with phosphorus content from 0.00% to 0.08% were tested using several engine and bench tests to evaluate their antiwear properties, oxidation stability and friction reduction durability. In these tests, oils containing more than 0.02% of phosphorus were able to fulfill ILSAC GF-4 performance standards with optimized additive formulation. MoDTC helped to replace several functions of ZnDTP in low phosphorus engine oils.

JCAPII gasoline workgroup reported vehicle emission study to comprehend the impact of ETBE blending. In previous study, we focused on the compatibility of ETBE blended gasoline with Japanese current gasoline vehicles in-use. Based on recent discussion with ETBE 8% blended gasoline into the market, more information becomes necessary. In this second report, we studied to comprehend the actual emission impact using realistic model fuels using several base stocks. Fuel properties of T50, T90 and aromatic compound content were selected through discussions. Specifications were changed within the range of the market. Both ETBE 0% and 8% were combined for these fuel matrixes. In total, eight fuels and two reference fuels were tested. Two J-ULEV vehicles (one MPI, and a stoichiometric-SIDI) were procured as representatives. We discussed quantitative and qualitative impact toward emissions. Data regarding CO2 and fuel economy change were also reported.

Clarifying the impact of ETBE 8% blended fuel on current Japanese gasoline vehicles, under the Japan Clean Air Program II (JCAPII) we conducted exhaust emission tests, evaporative emission tests, durability tests on the exhaust after-treatment system, cold starting tests, and material immersion tests. ETBE 17% blended fuel was also investigated as a reference. The regulated exhaust emissions (CO, HC, and NOx) didn't increase with any increase of ETBE content in the fuel. In durability tests, no noticeable increase of exhaust emission after 40,000km was observed. In evaporative emissions tests, HSL (Hot Soak Loss) and DBL (Diurnal Breathing Loss) didn't increase. In cold starting tests, duration of cranking using ETBE 8% fuel was similar to that of ETBE 0%. In the material immersion tests, no influence of ETBE on these material properties was observed.

Emission regulations for diesel-powered vehicles have been gradually tightening. Installation of after-treatment devices such as diesel particulate filters (DPF), NOx storage reduction (NSR) catalysts, and so on is indispensable to satisfy rigorous limits of particulate matter (PM) and nitrogen oxides (NOx). Japan Clean Air Program II Oil Working Group (JCAPII Oil WG) has been investigating the effect of engine oil on advanced diesel after-treatment devices. First of all, we researched the impact of oil-derived ash on continuous regeneration-type diesel particulate filter (CR-DPF), and already reported that the less sulfated ash in oil gave rise to lower pressure drop across CR-DPF [1]. In this paper, impact of oil-derived sulfur and phosphorus on NSR catalyst was investigated using a 4L direct injection common-rail diesel engine with turbo-intercooler. This engine equipped with NSR catalyst meets the Japanese new short-term emission regulations.

The addition of molybdenum dithiocarbamate (MoDTC) to engine oil improves the fuel consumption of vehicles. However, this is also widely known to cause deposit accretion in the Thermo-Oxidation Engine Oil Simulation Test (TEOST 33C). Thus the effects of additives on TEOST 33C and elemental analysis of the deposits were evaluated to analyze the deposit formation mechanism in TEOST 33C by engine oil containing MoDTC. An elemental analysis of deposits revealed that most consisted of carbide and contained small amounts of molybdenum compounds. Deposit accretion was not caused due to the remarkable increase of compounds derived from MoDTC. It was assumed that they acted as a decomposition catalyst under high temperature and induced carbide to be deposited.