Liquid mixture consisting of diesel gas oils and oxygenated compounds

Abstract

A liquid mixture having a cetane number higher than 40, comprising a typical diesel gas oil cut having a boiling point ranging from 150 to 380° C., and a density ranging from 0.76 and 0.935 g/ml at 15 ° C.; and one or more compounds selected from dialkyl-polyformals represented by the formula RO(CH 2 O) m R, wherein R is a C n H 2n+1 alkyl chain, m is an integer equal to or greater than 2 and less than or equal to 6, n is an integer ranging from 1 to 10, wherein the concentration of these dialkyl-polyformals in the gas oil ranges from 1 to 20%; and a process for production of dialkyl-polyformals using sulfonic acid-based catalysts.

1 ) A liquid mixture having a cetane number higher than 40 characterized in that it consists of: 
 a typical diesel gas oil cut having a boiling point ranging from 150 to 380° C. and a density ranging from 0.76 to 0.935 g/ml at 15° C.;    one or more compounds selected from dialkyl-polyformals represented by the formula    RO(CH 2 O) m R,    wherein R is a C n H 2+1  alkyl chain, 
 m is an integer equal to or greater than 2 and less than or equal to 6,  
 n is an integer ranging from 1 to 10,  
   wherein the concentration of said dialkyl-polyformals in the gas oil ranges from 1 to 20% by volume.    
     
     
         2 ) The liquid mixture according to  claim 1 , wherein m is equal to or greater than 3 and n is equal to 1 or 2.  
     
     
         3 ) The liquid mixture according to  claim 2 , wherein m is equal to or greater than 3 and less than or equal to 5 and n is equal to 1.  
     
     
         4 ) The liquid mixture according to  claim 1 , wherein the dialkyl-polyformals are in a concentration in the gas oil in a quantity ranging from 4 to 11%.  
     
     
         5 ) The liquid mixture according to  claim 1 , wherein the typical diesel gas oil cut has a boiling point ranging from 200 to 350° C.  
     
     
         6 ) The liquid mixture according to  claim 1 , wherein cetane raisers are added to the typical diesel gas oil cut.  
     
     
         7 ) The liquid mixture according to  claim 6 , wherein the cetane raisers are in a concentration in the diesel gas oil of up to 1% by weight.  
     
     
         8 ) The liquid mixture according to  claim 6 , wherein the cetane raisers are selected from nitro-derivatives and dialkyl-peroxides.  
     
     
         9 ) A process for the production of dialkyl-polyformals represented by the formula RO(CH 2 O) m R, 
 wherein R is a C n H 2+1  alkyl chain,    m and n are integers ranging from 1 to 10,    effected by means of reaction (1) and/or reaction (2) as follows:    2ROH+mCH 2 O→RO(CH 2 O) m R+H 2 O  (1) RO(CH 2 O)R+(m−1)CH 2 O→RO(CH 2 O) m R  (2)    characterized in that it uses, as catalysts, sulfonic acids or sulfonic acids substituted with halogens, operating at temperatures ranging from 50 to 200° C.    
     
     
         10 ) The process according to  claim 9 , wherein the operating pressures range from 0.1 to 1 Mpa.  
     
     
         11 ) The process according to  claim 9 , wherein the concentration of the sulfonic acid ranges from 0.00001 to 0.01 M.  
     
     
         12 ) The process according to  claim 9 , wherein reaction (1) is carried out with a molar ratio formaldehyde/alcohol greater than 0.1 and with a molar ratio alcohol/sulfonic acids or alcohol/substituted sulfonic acids greater than 100.  
     
     
         13 ) The process according to  claim 9 , wherein reaction (2) is carried out with a molar ratio formaldehyde/dialkylformal greater than 0.1 and with a molar ratio dialkylformal/sulfonic acids greater than 100.  
     
     
         14 ) The process according to  claim 9 , wherein reaction (1) is effected first, wherein m is equal to 1, by reacting the alcohol with formaldehyde and obtaining dialkyl-monoformal and water and subsequently reaction (2), wherein m ranges from 1 to 10, by reacting the dialky-lmonoformal and formaldehyde.  
     
     
         15 ) The process according to  claim 14 , wherein reaction (1) is effected in a first step wherein the dialkyl-monoformal obtained is separated from the water and reaction (2) is effected in a second step to which the separated dialkyl-monoformal is sent.  
     
     
         16 ) The process according to  claim 14  or  15 , wherein reaction (1) is effected with a molar ratio formaldehyde/alcohol greater than 0.1 and with a molar ratio alcohol/sulfonic acids or alcohol/substituted sulfonic acids greater than 100 and reaction (2) is effected with a molar ratio formaldehyde/dialkylformal greater than 0.1 and with a molar ratio dialkylformal/sulfonic acids greater than 100.  
     
     
         17 ) The process according to  claim 16 , wherein reaction (1) is effected with a molar ratio formaldehyde/alcohol greater than 0.5 and with a molar ratio alcohol/sulfonic acids or alcohol/substituted sulfonic acids greater than 500 and reaction (2) is effected with a molar ratio formaldehyde/dialkylformal greater than 0.5 and with a molar ratio dialkylformal/sulfonic acids greater than 500.  
     
     
         18 ) The process according to  claim 9 , wherein the sulfonic acids substituted with halogens are perfluoroalkanesulfonic acids.