Patent Publication Number: US-4369043-A

Title: Process for the preparation of high octane value substitute fuel for a spark ignition type internal combustion engine

Description:
This application is a continuation in part of Ser. No. 186,644 filed Sept. 12, 1980, now abandoned. 
    
    
     This invention relates to a fuel composition and process for making a fuel with high octane value for use in a spark ignition type internal combustion engine. More particularly, this invention relates to a process for preparing a substitute fuel composition comprising mixing 70.6% of a mixture of 65.0% methanol, 0.6% methanol+stearic acid (40:1) and 5.0% benzene, 20.4% of a mixture of 20.0% water, 0.3% dextrin and 0.1% phenol, 5% of combustion-accelerant consisted of 0.70% stearic methyl dichloride, 0.35% ethylene dichloride, 0.85% xylene, 0.02% lead acetate, 2.50% acetone and 0.57% aluminum stearate+acetone (1:40) as surfactant and 4.0% oxalic acid (1 Kg)+dimethyl ether (201) as antiknock agent; stirring said mixtures at 150-200 rpm for 2-3 minutes at 10°-40° C. and preserving them for 48-72 hours at room temperature. 
     The fuel according to the invention will have the same efficiency as gasoline without causing operating problems in the internal combustion engine. The raw materials for the fuel are readily available domestically, thereby avoiding the necessity to import fuels from abroad. Further, as the fuel produces no smoke when combusted, it prevents contamination of the natural environment. 
     Hitherto, many proposals have been made for preparing substitute fuel such as the fuel according to the invention. However, all these fuels are derived from the crude oil or the existing gasoline itself and have many faults. Namely, prior synthetic fuels based on the commercial gasoline have chemical and physical properties similar to those of the raw gasoline. 
    
    
     An object of this invention, therefore, is to provide a new fuel oil, eliminating the aforementioned drawbacks. 
     For reference, standards of gasoline which is commercially available will be illustrated as below: 
     
         __________________________________________________________________________
(JIS K 2202-65; gasoline for automobiles)                                 
            distillation (loss considered)       Cu-plate                 
                                                        vapor press.      
   octane   10% eff. temp.                                                
                    50% eff. temp.                                        
                            60% eff. temp.                                
                                    70% eff. temp.                        
                                            residue                       
                                                 corrosive                
                                                        (37.8°     
                                                        C.,               
type                                                                      
   value                                                                  
       reaction                                                           
            °C.                                                    
                    °C.                                            
                            °C.                                    
                                    °C.                            
                                            vol %                         
                                                 (50° C.,          
                                                        Kg/Km.sup.2)      
__________________________________________________________________________
#1 95  neutral                                                            
            70      125     180     205     2.0  1      0.45              
#2 85                                                   0.80              
__________________________________________________________________________
 
    
     (1) The above prior gasoline should not be washed, but those in the range of 5/100-20 mg/100 ml may be washed with a prescribed solvent to afford a practical point, 5 mg/100 ml. 
     (2) Any of lead alkyl compounds may be used except for lead tetraethyl. The amount of the lead alkyl, when calculated as metallic lead, may correspond to the amount of lead in lead tetraethyl. 
     Fuel, in general, should be inactive to metallic materials of apparatus and/or equipment in which said fuel is used, and should not be stand in its moving and pumping. Also, due to the high vapor pressure, problems such as vaporization, saturation and the like must not occur. When starting or running the engine, ignitionability and combustionability must be excellent, but when the engine is shut down, the ignition should not continue due to residual pressure. 
     As previously described, substitute fuels, proposed to the present, are not valuable in light of economic considerations. The fuels could not be prepared and manufactured at a large scale and do not solve the problems in connection with smoke-production and public pollution. (3) Lead tetraethyl or other lead alkyl has a characteristic property, and, therefore, the fuel may be colored to indicate that it contains the lead component. This has no relation with octane value. For a reference, according to KSM 2612, 1478-12-12 gasoline has the following properties: 
     
         __________________________________________________________________________
            Distillation                                                  
            10%   50% 90%                                                 
            eff.  eff.                                                    
                      eff.      Cu-                                       
Octane Value                                                              
            temp. temp.                                                   
                      temp. residue                                       
                                plate                                     
type                                                                      
   Res.  Mor.                                                             
            °C.                                                    
                  °C.                                              
                      °C.                                          
                            vol %                                         
                                corr.                                     
__________________________________________________________________________
#1 95    87 70    125 190   2.0 1                                         
#2 91    83                                                               
#3 86    79                                                               
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   vapor color       lead     oxd.                                        
                                  water                                   
   press.                                                                 
         when        tetra-   sta-                                        
                                  and                                     
   (37.8° C.                                                       
         lead gum    ethyl                                                
                         sulfur                                           
                              bility                                      
                                  ppt.                                    
type                                                                      
   Kg/Km.sup.2)                                                           
         added                                                            
              (mg/100ml)                                                  
                     (ml/l)                                               
                         (wt %)                                           
                              (min)                                       
                                  (wt %)                                  
__________________________________________________________________________
#1 0.45  colored                                                          
              5.0    0.3 0.01 480 0.01                                    
#2 0.85                                                                   
#3                                                                        
__________________________________________________________________________
 Note:-                                                                   
 1. The upper limit of atmospheric pressure is 0.98 when used under cold  
 climate.                                                                 
 2. Octane value was tested either by Research or Motor method.           
b.p.:                                                                     
    64.5-64.65° C.                                                 
             (760mm Hg)                                                   
                    In summer, vaporization and                           
    8° C.                                                          
             (50mm Hg)                                                    
                    saturation can be controlled by                       
    -16° C.                                                        
             (10mm Hg)                                                    
                    added solvents.                                       
m.p.:                                                                     
    -94.9° C.                                                      
                    In winter, start operation is efficient.              
s.g.:                                                                     
    0.7924 (20/20° C.)                                             
f.p.:                                                                     
    12.2° C. (closed)                                              
                    Good startability.                                    
    15.6°  C. (open)                                               
vis-                                                                      
cosity:                                                                   
    0.59CPS (20° C.)                                               
                    Good flowability.                                     
Combustion heat:                                                          
         183 kcal/MOI (gas)                                               
                    Short heat may be supplied by                         
         173 kcal/MOI (liquid)                                            
                    second and third solvent.                             
__________________________________________________________________________
 
    
     It has been found that benzene enhances the initial ignition efficiency of gasoline when it is added to the gasoline. Benzene has the following physical properties: 
     b.p.: 80.103° C.; m.p.: 5.506° C.; specific gravity: 0.87902 (20° C.); 0.87368 (25° C.); flammable point: -11.1° C.; viscosity: 0.6487 CPS (20° C.), 0.6028 (25° C.); combusion hear: 781.2 KCal/mol (gas), 783.4 KCal/mol (liquid). Dimethyl ether has the following properties: 
     b.p.: 56.2° C. (760 mm Hg), 56.1-56.5 (760 mm Hg), 56.24-56.5 (760 mm Hg); m.p.: -94.3° C., -94.6, -95.35; specific gravity: 0.7898; flammable point: -17°-16.2° C. (closed), -9°-10° C. (open); combustion heat: 426.8 kcal/mol. 
     As described above, the fuel of the invention can be composed by diluting a mixture of methanol, benzene, ether, dextrin and stearic acid, followed by admixing 5% by volume combustion accelerant to said diluted mixture. 
     The combined vapor pressure of the vapor-liquid of methanol-water build up by a composition thereof is generally set forth below: 
     
         ______________________________________                                    
methanol                                                                  
       temp.    press.   methanol                                         
                                 temp. press.                             
(%)    (°C.)                                                       
                (mm Hg)  (%)     (°C.)                             
                                       (mm Hg)                            
______________________________________                                    
100    18.7     45.3     50.4    15.5  27.7                               
       35.5     106.3            40.6  117.5                              
       49.5     215.3            60.1  301.4                              
       65.4     443.8            70.3  473.4                              
       78.5     766.5            80.5  720.0                              
87.7   17.4     35.9     33.13   21.15 85.1                               
       40.7     133.3            40.9  107.1                              
       60.5     346.4            60.45 281.6                              
       70.2     532.5            70.4  436.7                              
       79.9     739.5            80.25 654.0                              
68.12  18.1     34.2                                                      
       40.5     123.0                                                     
       60.7     327.8                                                     
       70.4     509.7                                                     
       80.5     768.7                                                     
______________________________________                                    
 
    
     The mean composition of the vapor-liquid of dimethyl ether (CH 3  --O--CH 3 ) and water, and ether and methanol, respectively, are shown in the following table. 
     
         ______________________________________                                    
Ether (mol %)                                                             
             temp.   Ether (mol %)  temp.                                 
liq. phase                                                                
       gas phase °C.                                               
                         liq. phase                                       
                                 gas phase                                
                                        °C.                        
______________________________________                                    
0.0     0.0      100.0   50.0    85.1   59.8                              
1.0    27.9      92.0    60.0    86.3   59.2                              
2.5    47.0      84.2    70.0    87.5   58.8                              
5.0    63.0      75.6    80.0    89.7   58.2                              
10.0   75.4      66.9    90.0    93.5   57.4                              
20.0   81.3      62.4    95.0    96.2   56.9                              
30.0   83.2      61.1    97.5    97.9   56.7                              
40.0   84.2      60.3    100.0   100.0  56.5                              
Total pressure was 760mm Hg.                                              
______________________________________                                    
Ether (mol %)  temp.   Ether (mol %)                                      
                                    temp.                                 
liq.       gas     (°C.)                                           
                           liq.   gas   (°C.)                      
______________________________________                                    
0.0        0.0     64.6    55.0   62.1  56.0                              
2.0        4.7     64.0    60.0   65.5  55.8                              
5.0        10.8    63.0    65.0   69.1  55.6                              
10.0       19.6    61.6    70.0   72.6  55.5                              
15.0       27.0    60.5    75.0   76.3  55.4                              
20.0       33.5    59.5    80.0   80.02 55.4                              
25.0       38.8    58.7    80.1   80.1  55.4                              
30.0       43.2    58.1    85.0   83.6  55.4                              
35.0       47.6    57.4    90.0   88.5  55.6                              
40.0       41.4    56.9    95.0   94.1  55.8                              
45.0       54.9    56.5    98.0   97.7  56.0                              
50.0       58.8    56.2    100.0  100.0 56.1                              
______________________________________                                    
 
    
     From the foregoing, the materials of the invention must be mixed at a predetermined ratio to achieve its boiling point of 30°-200° C., which is the same as that of the commercial gasoline. The mixing ratio will be the most important issue to solve the problems as described in the beginning of the description of the invention. Being mixed with methanol and water at an appropriate mixing ratio, benzene serves as explosive accelerant. Thus, the mixture has a good ignition power, although it is somewhat immiscible. Further, it is difficult to control its vapor pressure, and its heat amount is poor. However, if benzene is mixed with ether (R--O--R&#39;), such as dimethyl ether and lead acetate, the mixture has a good flammable point and combustionable state. In other words, gasoline, when used in an internal combustion engine, is combined with air to obtain a combined gas mixture which is compressed, ignited and exploded to cause a reciprocal movement of piston. The engine is operated through a cycle of suction-compression-explosion-discharging. 
     Gasoline, as a compound consisting of carbon and hydrogen, can be obtained either from crude oil and/or coal and has high calories (11,000-11,500 calories per kg) and low specific gravity (0.67-0.76 at 15°-4° C.). In a composition consisted of methanol (flammable point: 15.6° C.; b.p.: 64.5° C.), benzene, dimethyl ether, xylene, and combustion accelerants, an approximately similar state may be achieved. When common gasoline is burned, oxygen (air) must consistently be supplied in order to build up a good combustion condition. To the contrary, the fuel of the invention produces oxygen during combustion the fuel, and, therefore, the use of the fuel will cause the lower output and starting spark due to the excess of air because the fuel does need lower wastage of air over gasoline. 
     The other components, dextrin and stearic acid, are used as modifiers. The surfactant is used as a cleaner of carburetor valve. An exemplary surfactant is acetone and aluminum stearate. An example of the fuel composition will be described below. All percentages are by volume unless otherwise stated. 
     
         ______________________________________                                    
Sample                                                                    
      Components           Volume   Ratio                                 
______________________________________                                    
A     1. Methanol          65.0%                                          
      2. Methanol + Stearic Acid                                          
                           0.6%     70.6%                                 
       (40:1 by wt.)                                                      
      3. Benzene           5.0%                                           
B     1. Water             20.0                                           
      2. Water + Dextrin   0.3%     20.4%                                 
      3. Phenol            0.1%                                           
C     1. Stearic Methyl Dichloride                                        
                           0.70%                                          
      2. Ethylene Dichloride                                              
                           0.35%                                          
      3. Xylene            0.85%                                          
      4. Lead Acetate      0.02%    5.0%                                  
      5. Acetone           2.50%                                          
      6. Aluminum Stearate + Acetone                                      
                           0.57%                                          
       (1:40 by wt.)                                                      
D     1. Oxalic acid (1Kg) +                                              
                           4.0%     4.0%                                  
       Dimethyl Ether (202)                                               
______________________________________                                    
 
    
     The fuel of the invention is manufactured by mixing the above four mixtures. The fuel is tested as follows: 
     
         ______________________________________                                    
                                     Cu-plate                             
                  s.p.   f.p.   b.p. corrosive                            
types                                                                     
     heat amount  (°C.)                                            
                         (°C.)                                     
                                (°C.)                              
                                     (50° C., 3h)                  
______________________________________                                    
#1   7,000 cal    18     15.1   63.8 0.5                                  
#2   8,000 cal    19.5   15.6   64.1 1                                    
______________________________________