Total also has a low sulphur diesel equivalent - TOTAL ECO DIESEL PLUS - click here for word doc  data sheet

 What are the benefits of using Sasol TurboDiesel^TM?

The use of Sasol’s TurboDieselä has the following benefits:

·         Improved performance – Due to the cleaner and more efficient combustion characteristics of the diesel

·         Longer engine life – Due to reduced wear

·         Extended oil drain interval – Due to reduced soot formation and lubricant oil breakdown

·         Environmentally friendly – Due to reduced harmful exhaust emissions

Sasol TurboDiesel^TM is classified as a low sulphur diesel. How does the sulphur levels compare to other diesels?

In South Africa as from January 2001 the sulphur level in diesel allowed by the national specification is 0,3 mass % maximum. This requirement lags behind that applying in first world countries where most diesel engines are developed. In Europe for instance the specification was 0,3 % in 1989 and was reduced to 0,05 % in 1995. Sasol Turbodiesel^TM meets the advanced requirement of vehicle manufacturers by guaranteeing a maximum sulphur level of 0,05 %. 

What are the effects of the lower sulphur level of Sasol TurboDiesel^TM?

Sulphur in diesel forms sulphuric acid that play a major role in increasing engine wear. When Sasol Turbodiesel^TM is combusted, far less sulphuric acid is formed and hence engine wear rates are significantly reduced.

Sulphur in diesel leads to the formation of sulphate particulates.  In the engine oil, these cause depletion of the additives and thickening of the engine oil.  Use of Sasol Turbodiesel^TM reduces oil breakdown and thickening and hence engine wear is reduced and oil drain intervals can be extended.  Vehicle tests have shown that drain intervals can be doubled when Sasol TurboDiesel^TM is used.

The sulphate particulates, that leave the exhaust and that form in the air from sulphur dioxide emissions, also negatively effect air quality.

Why is Sasol TurboDiesel^TM classified as a low emission and environmentally friendly diesel?

Sasol TurboDiesel^TM reduces harmful exhaust emissions due to its low content of harmful sulphur and polynuclear aromatics, as well as its improved combustion properties.

The sulphur level of low emission diesel in South Africa is a maximum of 0,15 %, versus a maximum of 0,05 % for Sasol TurboDiesel^TM.  This 67 % reduction gives a proportional direct reduction of harmful sulphur dioxide and sulphate particulate emissions.   Sasol Turbodiesel^TM meets and exceeds all the requirements for low emission diesel according to the South African national specification. The content of polynuclear aromatics in European diesel must be less than 11 %.  Sasol Turbodiesel^TM has less than 5 %.

Does Sasol TurboDiesel^TM cost more?

To refine a superiour low sulphur diesel, that has properties such as Sasol Turbodiesel^TM, costs significantly more.  A higher margin of approximately four cents per liter, that does not cover such full additional costs, has been provided for by regulations.  However, the pump price of diesel is not regulated, so the actual price will vary from site to site.  The cost savings of using a superior diesel, such as Sasol TurboDiesel^TM , vary from application to application, but are typically greater than four cents per liter, so most users will benefit from demanding Sasol TurboDiesel^TM.

Do the vehicle manufacturers advise the use of Sasol TurboDiesel^TM?

Modern diesel vehicles are designed for operation with low sulphur diesel.  NAAMSA, representing the vehicle manufacturers, strongly support the initiative to make low sulphur diesel available.  The specific benefits, such as extended service intervals, depend from manufaturer to manufacturer.

Can Sasol TurboDiesel^TM be mixed with other diesels?

Yes, Sasol is fullly compatible with all other diesels.  Mixing will improve the other diesel, so that the quality of the mixture would be between that of the superiour Sasol TurboDiesel^TM and that of the standard diesel.

How can I know if the diesel that I am buying is Sasol TurboDiesel^TM?

Sasol TurboDiesel^TM is dyed purple to enable easy visual identification. 

What are the lubrication properties of Sasol TurboDiesel^TM?

Sasol TurboDiesel^TM exceeds all international lubricity requirements.  A latest technology lubricity additive is added to every batch of Sasol TurboDiesel^TM.

Petrol has an octane rating, but diesel does not.  Diesel has a cetane rating.  What is cetane?  How does the cetane of Sasol TurboDiesel^TM compare to other diesels?

Cetane is essentially the inverse of octane and applies to diesel, ie. fuel for compression ignition engines. The higher the cetane number the easier the spontaneous ignition (combustion caused simply by pressure and temperature) of the diesel.

In South Africa the minimum cetane requirement according to the national SABS specification is 45.  This specification, as for that for petrols, is agreed by oil companies, vehicle manufacturers and major users.   Sasol TurboDiesel^TM typically has a catane number of between 47 and 50.  The benefits of higher cetane number are better cold starts, smoother running and improved efficiency, particularly at high engine speeds.

Why is Sulphur in diesel bad for a diesel engine?

Sulphur in diesel forms sulphur oxides during combustion, which promotes particulate formation in the exhaust gas. A reduction in sulphur reduces this effect significantly. Sulphur oxides further react with moisture present in the combustion chamber to form sulphuric acid which causes corrosion on the cylinder liner and piston. Low sulphur diesel reduces these phenomena substantially. This also enables an increase in oil drainage intervals as basic additives in the engine oil that sustain Total Base Number (TBN) have a much reduced depletion rate.

Where is Sasol’s TurboDiesel available?

See list.

Does Sasol guarantee the performance of TurboDieselä ?

All fuels at the Sasol branded fuel pump are performance guaranteed.

Would I experience any problems with my vehicle when changing from the conventional diesel to Sasol TurboDieselä?

Sasol TurboDieselä is fully compatible with all diesel vehicles. Thus the  use of Sasol TurboDieselä in vehicle which previously used the high sulphur diesel would only result in benefits to the motorist.

The South African diesel specification (SABS 342) allows a maximum sulphur content of 0.55 %. In Europe, Japan and the USA, where our diesel engines are designed, the limit is  0.05 %.  The motor vehicle manufacturers desire that this be brought further down to 0.003 %. Sasol’s  ultra low sulphur diesel contains less than 0,001 % sulphur.

Sasol low sulphur diesel provides the following three major benefits.

·        It reduces wear and extends engine life (refer to the graph above that shows that compared to 0.55 % that this can give a doubling in engine life)

·        It reduces oil breakdown and allows extended service intervals and reduced maintenance costs.

·        It reduces harmful exhaust gas emissions.  Particulate emissions are reduced by 40 % on average for typical South African diesel vehicles.

These advantages have been shown to give a 2 % saving in total operating costs for heavy duty diesel trucks.  The benefit for light duty diesel passenger cars and bakkies are even greater.  The latest generation and more advanced high pressure turbo-diesel engines benefit the most. 

Despite the obvious environmental benefits of reducing the sulphur content of diesel there are other considerations, such as whether the process is financially feasible for South Africa's petroleum producers. With the imminent increased use of diesel, commensurate with the intended introduction of diesel-powered taxis in South Africa, a cleaner diesel is going to be an even more sought-after reform.South African Petroleum Industry Association (Sapia) director Colin McClelland explains that diesel with a 0,3% sulphur content is 2c more expensive than 0,55% sulphur-content diesel, and that this increases to almost 10c/l at lower sulphur levels. He states that sulphur content could be reduced even further in the next five to six years. "Certain users, such as farmers for example, may not want to spend another 8c/l to 10c/l when it has no apparent benefit to them, so there is a trade-off between environmental benefits and economic considerations," he points out. Prices will primarily be driven up by several hundred million randsworth of modifications that would be needed at refineries to enable them to produce lower-sulphur-content diesel. 

Sapia environmental advisor Anton Moldan explains that the January 2002 deadline has been set by mutual agreement between Sapia, Sasol, the National Association of Automobile Manufacturers of South Africa, the Department of Minerals and Energy, the Road Freight Association and environmental interest groups. "Each refinery has different configurations and, thus, needs different modifications. "However, in general, they will all need to increase their sulphur-recovery capacity by adding hydrodesulphurisation units," he says.He estimates that this will cost about R400-million. 

Another option to produce diesel with a lower sulphur content is for refineries to buy different grades of crude oil, explains McClelland. Lighter crude oil has more petrol and diesel, while heavier crude has a higher fuel-oil (tar, bitumen) content, and 'sweet' crude has less sulphur content, while 'sour' crude has more. "Sweet crudes would cost more to buy, but this would be the simplest way to get less sulphur in diesel. "However, this is only the simplest way to move off initially high levels of sulphur content to lower levels to a limited extent, but is not the whole answer for reaching the desired low levels," he expresses. McClelland adds that it is pointless to move the sulphur from the diesel into the environment in the process of extracting it in therefinery. 

McClelland adds that another important factor which needs to be taken into account in the diesel debate is whether policy should encourage local refining in the long term, taking into account a move towards more stringent product specifications that require larger investments in equipment from refineries to meet. "Some countries rely more on imported products, while others, such as South East Asia, Singapore and the UK, for example, have regional refining centres. "It would make sense to me that South Africa should continue to have its own refining centre - South Africa's east coast and Durban are logical places. "Advantages of this include foreign exchange savings because, when crude oil is processed at a refinery, the market is saved the foreign exchange expensesassociated with imported product. "This could also provide greater security of supply in the event of a tight global market, in that the refinery could compensate if there is a world refinery-capacity shortage," he elaborates.McClelland adds that this could further promote local job creation. 

Although refineries create only about a thousand jobs, the maintenance and supply of goods and services could create significant indirect employment opportunities. Along with this come educational advantages, such as the development of chemical engineers and apprentices. McClelland reports that there is currently a study under way - due for completion by March 2001 - to determine fuel quality, withspecific focus on sulphur content in diesel, while taking economic considerations into account, in order to determine a way forward. "The position of the industry is such that we are willing to participate in debate to see what the levels are, and industry will not block moves to lower sulphur content, but there needs to be a return on that investment," he stresses. 

Sasol technical services manager Raoul Goosen affirms that the costs involved vary from each refinery, depending on its current infrastructure and capacity. "If additional reactors or more hydrogen is needed, then the capital expenditure would be large - costs could vary from a fewmillion to several hundreds of millions of rands," he reports. Goosen adds that Sasol supported the move to reduce sulphur content to 0,3 %, as it benefits the country to the tune of R800-million. "In the case of the Sasol Synfuels plant at Secunda, Mpumalanga, the diesel does not contain sulphur and inherently meets the future proposed European levels of less than 0,005 %. "This inherent property makes this diesel sought-after and valuable. "In the case of the Sasol-owned Natref refinery, no expenditure is needed to meet the 0,3% sulphur level."For the possible envisaged lower levels of 0,05%, Natref, along with all the other crude-oil refineries, will require capital expenditure. "However, because Natref already upgrades a more significant portion of our crude oil - due to having an inland refinery and having no marine fuel market - this places Natref in a better position to meet the requirements of producing lower-sulphur diesel at a more affordable cost," he elaborates. Goosen explains that, although Sasol Synfuels already produces and supplies ultra-low sulphur-content diesel, and Natref could begin producing 0,3% diesel immediately, due to the lack of financial incentives for the higher value product, Sasol would only implement sulphur reductions according to the timetable that has been set. 

While the move to lowering sulphur content in diesel is driven by emission requirements and environmental concerns abroad, in South Africa, the move to 0,3% was largely driven by performance, durability, technological and economic factors and to be more aligned with imported global vehicle technology. Goosen reports that one of the main advantages of reducing sulphur content to 0, 3% is the considerable savings to the users of diesel and, through them, to the country. He explains that, due to the current high sulphur content of diesel fuel, diesel-powered light-commercial vehicles in South Africa typically require servicing more frequently than their petrol-engined equivalents.This is due to the fact that sulphur is converted to sulphur-dioxide in the combustion process, which is then diffused into the oil layer coating the cylinder wall and piston rings.The sulphur dioxide then reacts with moisture present in the oil to form sulphur-type acids which, in turn, are responsible for corrosive wear.Sulphur also contributes to increased particulates (visible emissions) and thickening of the oil. The costs and inconvenience of the additional servicing are, reportedly, a large contributing factor to the unpopularity of diesel-passenger cars in South Africa. Lower engine-wear rates in diesel engines and increased service intervals - along with a reduced effect on the environment from emissions and waste oil disposal - is also anticipated.

Savings for passenger cars and heavy commercial vehicles, when diesel sulphur content is reduced to 0,3%, is estimated to vary from R550-million to R1,2-billion a year, due to longer engine life and reduced service intervals. This becomes an even more significant consideration when taking into account the government's plans to introduce a new diesel-powered taxi fleet.Despite this, Goosen cautions that the country would not necessarily reap all the benefits by transferring to low levels with the current relatively high age of vehicles. "The country will need to weigh up the benefits and assess how significant they will be to ensure that it gets the best value for the money that is spent," he says. 

BP Southern Africa automotive fuels and lubricants technical manager John Fitton reports that, to provide low-sulphur-content diesel, the company would need to build new desulphurising units to be able to treat the diesel components."The extent of this expansion would depend on the required sulphur level and other diesel parameters, but would cost more than several million dollars," he says. Fitton reports that BP has planned a shutdown for next year to install the required equipment for the reduction to 0,3% sulphur content. "The planning operation for this is significant, and will take until the end of next year to be ready," he says.Fitton explains that parent company BP Amaco has a global greener-fuels philosophy and supports the move to lowersulphur levels. He reports that BP is motivated by environmental concerns, and will do whatever it (economically) is able to do, to reduce potential harm to the environment. Fitton adds that to reach European levels would require significant spending by the oil industry, along with a cost to the consumer as regards diesel selling price, and would take four years for the necessary equipment to be put in place."The question is whether European fuel specifications are relevant for the South African economy in general, not as much in capital expenditure cost to the fuel industry, but as regards the benefit to the environment," he says. 

Shell Southern Africa fuels technical manager Hans Siemelink reports that the company is committed to achieving the 2002 timetable, and that Shell has been supplying South African mines with low-emission and low-sulphur diesel fuels for more than ten years.He adds that the move from 0,55% to 0,3% sulphur content requires a lead time and relocation of refinery expenditure - which has accounted for the 2002 deadline. Despite levels in the UK, parts of which currently operate at 0,05% and 0,03% sulphur content, Siemelink reports that such low levels are not automatically being considered for South Africa. "Such low levels in South Africa require significant capital investments - in the order of billions of rands - and an adequate amount of lead time," he points out. Siemelink affirms that the oil industry has agreed to a study, together with other participants, to determine the long-term future properties of diesel and petrol. "A longer-term study, beyond March 2001, between all participants needs to determine what air-quality problems we are trying to solve and how to tackle them, including a relook at lower sulphur levels, along with the other fuel properties of diesel and petrol. "The study will be concluded with a cost/benefit evaluation to determine what is best for South Africa," he asserts.Taking these points into account, it would appear that the days are numbered for dirty diesel, but that debate will continue to rage on how clean and green we should go.
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