144 ALCOHOL FUELS. 



Of all the alcohol fuels that I have tried I have found that 

 Natalite was the most satisfactory substitute for petrol. In the 

 early stages of manufacture we had innumerable complaints. Many 

 were very puerile, such as that the fuel ate away the cylinder 

 walls. I watched the exhaust valves as I expected to find a certain 

 amount of pitting there, but I never found any trouble. There 

 were also complaints of corrosion of tanks. In the early stages this 

 might have been true in a slight degree, as we had to use wood 

 naphtha as a denaturant. Since the use of Simonsen's oil and 

 pyridine as denaturants has been allowed these troubles have 

 ceased. Wood naphtha was always undesirable in a motor fuel. 

 It was frequently impure and contained small quantities of acetic 

 acid and also liberated acetic acid on combustion. Its calorific 

 value was also low. 



Pyridine on the other hand is an excellent denaturant. Its 

 unpleasant smell renders any alcohol fuel unpotable. It is difficult 

 to separate out and has the great advantage of liberating ammonia 

 on combustion, thus neutralizing the effect of any acid that may 

 be formed by the combustion of impure alcohol. 



Simonsen oil is simply crude petroleum with the asphaltic 

 fractions separated. It is useful as a fuel and a very good de- 

 naturant which is very difficult to separate out. It also has a 

 high calorific value. 



From time to time the bogey of corrosion is brought up in 

 connection with alcohol fuels, but I can confidently say after con- 

 siderable experience that it is non-existent if a pure alcohol is 

 used, say 96% alcohol, but if there is much aldehyde present there 

 is great danger of corrosion, as here again acetic acid is liberated 

 on combustion. I ran a car 25,000 miles on Natalite: at the end 

 of that time the engine was opened up and thoroughly examined. 

 There was no sign of corrosion anywhere. The colouring matter 

 is a slight drawback, even though the quantity is so small, amount- 

 ing to about \ oz. of methyl violet to 3 tons of fuel. Yet with 

 continuous use this small amount collects in the carburetter. It 

 would ba well if the Excise authorities could see their way to do 

 away with this requirement. 



While on this subject I should like to pay a tribute to the 

 Union Government and the Excise authorities for the sympathy 

 and courtesy which jthey have always extended to us. It is for this 

 reason that I think that we can claim that South Africa is one of 

 the first countries to make a practical success of an alcohol motor 

 fuel. 



It is often claimed by the inventors or authors of alcohol 

 motor fuels that the same mileage can be obtained with their fuels 

 as with petrol. I have never found this to be so with the excep- 

 tion of the mixture of benzol and alcohol previously mentioned, 

 which gave results very nearly equal to petrol. In this connection 

 I am talking of course of standard cars with standard petrol car- 

 buretters. 



We have put down a testing set at Merebank for testing the 

 comparative values of liquid fuels suitable for motor cars and other 



