HiTEC® 4678
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HiTEC® 4678
HiTEC® 4678 HiTEC® 4678 Multifunctional detergent For diesel fuel Report Number: Fuels 01/2008 Version 1 Date: May 2008 __________________ Chemist CONTENTS Page INTRODUCTION 2 INJECTOR DETERGENCY - THE MECHANISM 4 ENGINE TEST POLICY 6 INJECTOR DETERGENCY - TESTING 8 FUEL ECONOMY & EMISSIONS REDUCTION 11 FOAM CONTROL 13 CORROSION CONTROL 16 WATER DEMULSIFICATION 18 BIO-DIESEL COMPATIBILITY 19 PHYSICAL PROPERTIES 22 HiTEC® 4678 Page 1 INTRODUCTION Afton is the largest fuel additive addi producer worldwide and has been marketing a wide range of gasoline and diesel performance additives for a number of decades. Afton have a well established value proposition of adding value to fuels by harnessing technical innovation and global marketing expertise which allows oil companies to offer their customers a differentiated diesel quality. We strongly believe in: Working together. Delivering more.TM During the last few decades we have seen tremendous advances in the design of diesel engine technology as vehicle manufacturers strive to meet the more demanding government vehicle emissions regulations. This has also required oil companies to make available fuels which will allow new vehicle hardware to continue operating to the latest design design specifications. These changes are captured schematically below: In addition we are seeing changes to fuel quality driven by environmental concerns. The introduction of bio-fuels bio fuels is now a well established fact with fatty acid methyl ester (FAME) being permitted in EN590 diesel as a blend component at a level of 5% and there are currently discussions aimed at increasing this level to 10% in the near future. These fuels offer different challenges to additive companies who have to give re-assurance re that at the appropriate chemistry is available to maintain engine en performance with Bio-diesel use. You will see later in this report that Afton Chemical has conducted an extensive investigation into the impact of Bio-diesel Bio on products such as HiTEC® 4678. HiTEC® 4678 Page 2 HiTEC® 4678 is multifunctional by design and is the result of extensive research and development designed to achieve a high level of performance coupled with the reassurance of complete compatibility with modern diesel engine technology & evolving diesel specifications. The use of a product such as HiTEC® 4678 allows oil companies to market a premium quality diesel fuel. The recommended treat-rate of HiTEC® 4678 is 190ppmv. If used at the higher treat-rate of 256ppmv HiTEC® 4678 will deliver a demonstrable reduction in emissions and improved fuel economy. Engine protection will be provided at a treat-rate as low as 106ppmv. Initial additive development, performance and no harm testing is conducted in our state of the art engine test facilities based in Richmond, Virginia. This is complimented by more specific industry engine tests which are performed at local independent ISO accredited test facilities. HiTEC® 4678 will improve the performance of treated diesel by preventing the build up of deposits in the critical region of the engine and, at slightly higher treat-rates, will result in clean up and removal of existing deposits. The most critical part of the engine is the injectors. HiTEC® 4678 is a well established diesel performance additive with the following features: Excellent injector deposit control Significant reduction of injector flow loss Almost completely eliminates foam Fully compatible with Bio-diesel Low viscosity for easy handling Chlorine free HiTEC® 4678, used at the recommended treat-rate, will give up to 5 times more fuel flow in both older and modern types of diesel engine leading to the following performance benefits: Improvement in fuel economy & reduction in carbon dioxide emissions Significant reduction in undesirable emissions from the exhaust Reduced foaming during tank filling leading to quicker & cleaner filling Excellent corrosion control preventing filter blockage Prevent emulsion formation & improve water separation HiTEC® 4678 Page 3 INJECTOR DETERGENCY-THE MECHANISM All diesel fuels have a tendency to form small amounts of hard, carbonaceous deposits on the fuel injector nozzles of both direct injection and indirect injection diesel engines. This process is known to occur during the first few hours of operation, and then generally to persist throughout the lifetime of the nozzles. The build up of excessive amounts of these deposits will disrupt the spray pattern of the fuel from the nozzle, which can lead to serious drivability problems. Increased fuel consumption, high noise levels and increased emissions are some of the other problems attributed to excessive nozzle coking. The schematic below shows the design of an indirect injection pintle nozzle and the area where deposit build up is most likely to occur. The use of detergents will dramatically reduce the build up of deposits so that the flow of fuel through the injector is not impeded, resulting in a robust spray pattern. The stronger the spray pattern the better the fuel will mix with excess air leading to more complete combustion, improved fuel economy & lower emissions. Fuel detergents are generally associated with a range of amine type chemistries in which a polar amine group is reacted on to a hydrocarbon soluble backbone. The detergents function by surface active attachment of the polar head group to form a barrier film on the critical surfaces. There is also a dispersant action whereby the additive prevents agglomeration of particulate matter and keep it dispersed so that it is less likely to accumulate on the injector surfaces. Detergents have a solvent activity whereby the additive can dissolve pre-formed deposits. HiTEC® 4678 Page 4 Afton Chemical has a history of continued improvement in the potency of their diesel detergent additive dditive chemistry. The current product used in HiTEC® 4678 is based upon succinimide chemistry which has been be optimised to give state of the art performance both in keeping injectors clean and also to clean up dirty injectors. An indication of the chemistry chemistry of the Afton Chemical diesel detergent is shown below: A very similar mechanism occurs for the modern direct injection diesel engines except, due to the design of the injectors, it is not possible to quantify the effect of deposits of the fuel flow through the injectors. In this case the impact of deposit build up is measured indirectly by quantifying the loss of power power. HiTEC® 4678 Page 5 AFTON’S ENGINE TEST POLICY For a number of years it has been the policy of Afton to use internal engine testing only for research and development of new additive formulations. Afton has a state of the art research centre situated in Richmond, Virginia which is fitted with a number off engine tests including the standard Peugeot XUD XUD-9 and recently introduced Peugeot ugeot DW-10, DW and these engines are operated according to current CEC procedures. In most countries, including the European Union, the engine tests for evaluating detergent packages ges are agreed and formalised by the Coordinating European council (CEC). Representatives of the CEC working groups are from oil companies, equipment manufacturers and additive companies. The CEC protocol previously used for test development is summarised below: When generating data to support the performance of commercialised fuel additives, where possible, all testing is conducted in ISO accredited and independent engine test laboratories which are mostly situated in Europe. The engine laboratories used run the engine tests strictly according to the appropriate CEC test procedures and they also participate in regular round robin testing to ensure the engine severity is in-line in line with the industry standard. HiTEC® 4678 Page 6 The traditional performance test in terms of defining additive treat-rates is the Peugeot XUD-9, CEC-F-023, and particular care is taken to ensure this test is conducted correctly. Changes in engine technology and the increased use of bio-derived components is expected to see greater focus on the DW-10 test for future benchmarking. The repeatability and reproducibility of the XUD-9 test is re-established after every round robin but the current values are shown below: Peugeot XUD-9 The precision of the test has been assessed in round robin exercises in which CEC reference fuels were tested at a number of laboratories. The precision statistics for the Air Flow Loss for each fuel were as follows, where r refers to repeatability and R refers to reproducibility. The information in this bulletin is, to our best knowledge, sure and accurate, but all recommendations or suggestions are made without guarantee since the conditions of use are beyond our control. Afton Chemical Corporation and its affiliates disclaim any liability incurred in connection with the use of these data or suggestions. Furthermore, nothing contained herein shall be construed as a recommendation to use any product in conflict with existing patents covering any material or its use. HiTEC® 4678 Page 7 INJECTOR DETERGENCY - ENGINE TEST DATA There are two basic engine designs for diesel passenger cars in the current European car parc. Older designs of passenger diesel engines are based upon indirect injection technology where the fuel is sprayed through a pintle injector into a pre-combustion chamber. The purpose of the prechamber is to improve the efficiency of combustion by providing better fuel/air mixing prior to the fuel passing into the main combustion chamber. The industry standard engine test for indirect injection passenger technology is based upon the Peugeot XUD-9 engine. This test procedure was first developed in the mid 1980,s by a working group affiliated to the CEC. The initial test was published as the CEC-F-23-X-95 and this test was under development for up to 10 years. The test began as a 6 hour steady state test but after the 1997 CEC round robin it was declared that this test did not meet the statistical requirements of the CEC. In 1998 an alternative test procedure, using the same engine, was presented to the CEC working group. This test was based upon a 10 hour cyclic procedure and it was felt that this procedure was more likely to meet the CEC statistics requirement. After a very thorough investigation it was decided that the 10 hour test had significant improvements over the 6 hour test. Armed with strong repeatability & reproducibility data an application was made to move the procedure from ‘’X’’ status to ‘’T’’ status and this was granted in January 2000. The graph below indicates the level of performance that can be obtained with HiTEC® 4678 in the current European reference diesel. Remaining Flow @ 0.1mm 60 46 50 32 40 30 24.25 20 8 10 0 0 HiTEC® 4678 106 190 285 HiTEC 4678 Treat rate (ul/l) Page 8 More recently, direct injection common rail engines have been introduced to the European market by major car manufacturers as a means to meet the stringent emission limits of current European legislation. These modern diesel engines are fitted with very precise injection technology designed to help deliver better combustion efficiency with a consequent reduction in tailpipe emissions. However, over time deposits will build up on the critical parts of the diesel fuel injection equipment and these will not allow the engine to operate to its design specification. To maintain the performance levels attributed to modern engine designs it is important to keep the injectors clean and free of deposits. As a consequence, the current industry standard coking test, CEC F-23-01 (XUD9) originating from 1993 no longer meets the needs of the modern diesel car parc. A new test has recently been developed to monitor the performance of premium quality fuels to ensure that modern diesel engines are protected against the power loss and spray pattern degradation that can result from deposit build up on injectors. The new test is based upon the Peugeot DW10 2.0litre HDi engine operated with multi hole ‘sensitive’ injectors indicative of EURO V applications and supplied by Siemens. Engine power loss is evaluated during a 72 hour test cycle which consists of a total running time of 32hours. Vehicle manufacturers are indicating that 2% power loss could be considered as an acceptable performance limit for this test. The test now has official status and has been allocated the CEC F-9808(DW-10) nomenclature. There are two mechanisms that can be used to produce deposits in this test, one is based on the addition of zinc and the second requires the addition of 10% FAME. The use of zinc will lead to more acceptable reproducibility than FAME but FAME is seen as being more representative of current EN590 diesel fuel quality. HiTEC® 4678 has been evaluated using both these mechanisms and the results are shown graphically below: Power loss since SOT (%) HiTEC® 4678 performance in the direct injection Peugeot DW10 test Fuel treated with 1 ppm Zinc HiTEC® 4678 0 -1 0 -2 -3 -4 -5 -6 -7 -8 -9 -10 Engine run time (hrs) 8 16 24 32 Base + Zn Base + Zn + H4678 @ 380ppmw Page 9 HiTEC® 4678 performance in the direct injection Peugeot DW10 test Fuel blended with 10% FAME Power Loss [%] 4 2 0 -2 -4 -6 -8 -10 -12 -14 -16 -18 -20 -22 B10 + H4678 @ 190ppm B10 + H4678 @ 380ppm B10 0 4 8 12 16 20 24 28 32 36 40 44 48 Engine Run Time with Test Fuel [h] The data shown above demonstrates that HiTEC® 4678 gives good protection against power loss resulting from deposit build up in direct injection engines. At a treat-rate of 380ppm HiTEC® 4678 has given complete protection against power loss irrespective of the mechanism used to promote power loss. HiTEC® 4678 Page 10 FUEL ECONOMY & EMISSIONS REDUCTION It is a proven fact that when the injectors of a diesel vehicle suffer from flow loss as a consequence of deposit build up there will be a direct impact on the combustion efficiency of the vehicle. This loss of efficiency can be measured as a reduction in fuel economy and an increase in emissions. A number of different test cycles exist to quantify this impact. In 1990 a test program was conducted in the well established engine test laboratory of APL in Austria. The objective of the test was to measure the immediate and longer term advantages of using detergent to keep diesel injectors clean. The first test program was carried out in a Mercedes 200D taxi with a 2 litre naturally aspirated indirect injection engine. At the time of testing the vehicle had done 138000 kilometers on its original injectors. The effect of detergent in this vehicle was evaluated immediately and after 1000 kilometers of city, urban and high speed cruising. This test was run under a number of different test cycles but here we have focused on the European, ECE-15 test cycle results. The second test was conducted with a Volvo truck, which represents a direct injection heavy duty vehicle, and readings were taken immediately and after 60hours of operation. The test was run on a European ECE R49 test cycle The actual tests were conducted with 100ppm of an older generation diesel detergent. Based upon the nitrogen content of the detergents we can relate the performance measured in this test with the more potent detergent used in HiTEC® 4678. 100ppm of the old generation of detergent is equivalent to 54ppm of the current commercial diesel detergent and this is equivalent to 253ul/l of HiTEC® 4678. In conclusion the use of 253ppm HiTEC® 4678 will give the following performance benefits based upon the data generated from the AVL field trial reported above. The benefits are shown as percentage improvement. HiTEC® 4678 Page 11 Mercedes passenger car Volvo truck Volvo truck HiTEC® 4678 Fuel economy (ECE-15 cycle) Hydrocarbons (ECE-15 cycle) 2.2% 13% Fuel economy (Immediate) Hydrocarbons (Immediate) 1.3% 11.3% Fuel economy (After 60 hours) Hydrocarbons (After 60 hours) 1.6% 21% Carbon monoxide (ECE-15 cycle) 6% Carbon monoxide (Immediate) 8.6% Carbon monoxide (After 60 hours) 28% Particulates (ECE-15 cycle) 4.8% Particulates (Immediate) 8.3% Particulates (After 60 hours) 21% Page 12 FOAM CONTROL All diesel fuels have a natural tendency to produce foam when pumped into the tank of a diesel vehicle. Excessive foaming can cause motorists problems by "splashing-back" on them and increase re-fuelling times by prematurely activating the automatic fuel cut-off in service pump nozzles. Fuel spilling onto the service station forecourt also gives rise to environmental concerns. A small amount of anti-foam added to the fuel can significantly reduce the above problems. In addition, fuel marketers have seen the commercial advantages of using anti-foam additives in terms of the greater volume of fuel that can be added to a vehicle tank before the pump cuts-off. There are various methods for evaluating the performance of anti-foam. Methods range from simple handshake tests to vehicle tank filling tests. However, the industry recognised fuel foam test is based upon the BNPe rig using the NFM 07075 test procedure. Fuel is injected under pressure into a measuring cylinder and the initial height of the foam and the time taken for the foam to collapse are measured. The design of the test is shown below: HiTEC® 4678 Page 13 The effectiveness of HiTEC® 4678 in reducing fuel foaming was assessed using the BNPe (NFM 07-075) test. Fuel is injected under pressure into a measuring cylinder and the initial height of the foam and the time taken for the foam to collapse are measured. The fuel used for this test was the CEC RF93-T-95 reference fuel. European reference diesel Test No. 1 2 3 Additive None HiTEC® 4678 HiTEC® 4678 0 106 190 105 75 48 32 9.1 2 Treat-rate µl/l Foam Height (mm) Foam Decay Time (s) Testing has also been conducted in a European ultra low sulphur diesel fuel and excellent performance has been seen at the recommended treat-rate of 190ppm as tabulated below: Ultra low sulphur diesel fuel Test No. 1 2 Additive None HiTEC® 4678 0 190 100 17 42 1.9 Treat-rate µl/l Foam Height (mm) Foam Decay Time (s) The above results show that HiTEC® 4678 is effective at controlling the foaming tendency of diesel fuel and this can be demonstrated visually below: HiTEC® 4678 Page 14 HiTEC® 4678 Page 15 CORROSION CONTROL Corrosion in the fuel system of a vehicle can lead to severe problems. Not only can leaks develop in vehicle fuel tanks but particles of rust can block fuel lines and filters and, in severe cases impact fuel spray efficiency. The corrosion properties of diesel fuel are measured by using a dynamic corrosion test coupled with a NACE rating scheme. The test is published as ASTM D665A (using distilled water) and ASTM D665B (using synthetic seawater). In this method a mixture of 300ml diesel fuel and 30ml water are stirred at a temperature of 60 degrees Celsius for a period of up to 24 hours. A steel specimen is immersed in the liquid and this specimen is visually checked and rated according to the NACE scale shown below: NACE Rating A B++ B+ B C D E %age Rust None Less than 0.1% Less than 5% 5-25% 25-50% 50-75% 100% Pass/Fail Pass Pass Pass Fail Fail Fail Fail Original equipment manufacturers recognize the benefits of protecting the key engine parts from corrosion. HiTEC® 4678 is effective in imparting anti-corrosion properties to diesel fuels. The effectiveness of HiTEC® 4678 is readily demonstrated in CEC RF93-A-92 diesel fuel using the ASTM D665A (IP 135A) procedure. A rating of "B+" or better is generally considered to be a pass. The results of the ASTM D665A tests are as follows: HiTEC® 4678 Page 16 NACE RATING HiTEC® 4678 Base = C 190ppm HiTEC 4678=B+ Page 17 WATER DEMULSIFICATION Due to the detergency action of diesel detergents there is a risk of additive treated diesel retaining water and thus reducing the rate of separation of the water from the fuel. Multifunctional diesel additives are formulated with demulsifiers in order to give acceptable behaviour when in contact with water. HITEC® 4678 has been evaluated according to the ASTM D1094 test in a number of commercial diesel samples and meets the requirement of giving performance similar to untreated diesel. It can be seen that HITEC® 4678 provides good water shedding properties when treating at 190l/l. The results are illustrated below: Demulse Testing (ASTM D1094) Interface rating 4 +190ul/l HITEC® 4678 1b Separation rating 3 2 Vol.emulsion (ml) 5 0 Vol. Aqueous (ml) 15 20 BASE FUEL HiTEC® 4678 Page 18 HiTEC® 4678 PERFORMANCE IN BIO-DIESEL Fuels derived from renewable biological resources are known as bio-fuels. Animal fats and virgin and recycled vegetable oils derived from crops such as soybeans, rape seed, canola, corn and sunflowers can be used in the production of a fuel suitable for diesel engines called biodiesel (also known as FAME). Tall oil, produced from wood pulp waste, is another feedstock source. Biodiesel can either be used in its pure state or can be blended with conventional diesel fuel derived from mineral oil. A Directive was published by the European Parliament and the Council of the European Union in May 2003 to promote the use of bio-fuels in Europe. This Directive established a target of 2% bio-fuel consumption for road transportation by 2005 and then a 0.75% increase every year to achieve 5.75% by 2010. This was encouraged by the introduction of tax incentives for certain member states but still the targets are not being met, so now we are seeing a move towards mandating the use of bio-fuel components in certain European countries. The EN590 specification currently allows the use of up to 5% FAME in diesel fuel to be marketed at the service stations. There are currently attempts to convince the vehicle manufacturers that the level of FAME in diesel fuel could be safely increased to a level of 10% but as of today this has not been fully agreed. Since Afton Chemical is the market leader in diesel performance additives it was important to consider the impact of FAME on the current additive technology being used in the market. Since HITEC® 4678 is a well established product used throughout Europe it was decided to use this product to evaluate the performance impact of FAME. HITEC® 4678 was first evaluated for the effect it would have on injector coking. This impact was evaluated in both the indirect injection Peugeot XUD-9 engine test and the new Peugeot DW-10 direct injection test. Since the performance of HITEC® 4678 in diesel containing 10% FAME has already been demonstrated in the DW-10 on page 11 of this report we will focus on the performance in the Peugeot XUD-9 in this section. Testing was conducted in the Peugeot XUD-9 using standard commercial diesel fuel blending with different percentages of Soya methyl ester. The results of this evaluation are shown graphically below: HiTEC® 4678 Page 19 This testing shows that the addition of 5% FAME may have a slightly positive impact on the detergency characteristics of the base fuel. However, the FAME containing diesel will still benefit from the addition of an additive such as HITEC® 4678 both at the 5% and the 20% level of FAME addition. More testing has been conducted with diesel fuels containing FAME at the current commercial leve level and significant detergency benefits have been seen from the addition of HITEC® 4678 as shown below: An evaluation of HITEC® 4678 was conducted in a European diesel fuel which contained 5% rapeseed methyl ester. The results are shown graphically on the next ext page and indicate that HITEC® 4678 gives excellent improvement in detergency gency in current commercial biodiesel: bio HiTEC® 4678 Page 20 100 Remaining Flow @ 0.1mm 90 91 80 80.9 70 60 50 54.5 40 30 20 21.2 10 0 0 190 395 990 HiTEC 4678 Treat rate (ul/litre) The same commercial diesel fuel containing 5% FAME has been used to evaluate foam and corrosion performance with HITEC® 4678. The addition of HITEC® 4678 to the FAME containing diesel led to a 50% reduction in foam collapse time which is similar to the performance expected from normal fossil derived diesel fuel. In terms of corrosion performance we have seen a slight improvement in corrosion protection coming from the addition of FAME to fossil diesel and this can be still further improved by the addition of HITEC® 4678. This is demonstrated from the data tabulated below: Diesel %RME HITEC® 4678 Treat-rate ASTM D665A ASTM D665B RF06 0 0 E E RF06 0 190 A A RF06 5 0 B++ B+ RF06 5 190 A A RF06 10 0 B++ B+ RF06 10 190 A A HiTEC® 4678 Page 21 PHYSICAL PROPERTIES OF HITEC® 4678 Property Result Method Appearance Clear brown liquid Visual Odour Aromatic Flash point,PMCC, ○C 56 min ASTM D93 Sulphur content, mg/kg 22 Calculated Density at 15○C, kg/l 0.906 ASTM D4052 Nitrogen content, wt% 1.09 ASTM D5291 Chlorine content, mg/kg <20 TBN, mg KOH/g 27.6 ASTM D2896 TAN, mg/g KOH 1.3 ASTM D664 Silicon content, ppm 3100 ASTM D4951 Pour point, ○C -40 ASTM D97 Viscosity, cSt at 40○C 7 ASTM D445 Viscosity, cSt at -15○C 40 ASTMD445 Viscosity, cSt at -20○C 53 ASTM D445 Shelf life(Ambient) 18 months Aged evaluation HiTEC® 4678 Page 22 ASIA PACIFIC Afton Chemical Asia Pacific LLC 111 Somerset Road #09-05 Singapore 238164 T: +65 6732-0822 F: +65 6737-4123 EMEAI Afton Chemical Limited London Road, Bracknell Berkshire RG12 2UW England T: +44 1344 304-141 F: +44 1344 420-666 LATIN AMERICA Afton Chemical Industria de Advitivos LTDA Avendia Rio de Janeiro 901 (Parte) CEP-20931-670 Brazil T: +55 21 3860-9994 F: +55 21 2580-8647 & 2589-0531 NORTH AMERICA Afton Chemical Corporation 500 Spring Street Richmond VA 23219 USA T: +1 804-788-5800 F: +1 804-788-5184 www.aftonchemical.com