Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10C—WORKING-UP PITCH, ASPHALT, BITUMEN, TAR; PYROLIGNEOUS ACID
  • C10C3/00—Working-up pitch, asphalt, bitumen
  • C10C3/02—Working-up pitch, asphalt, bitumen by chemical means reaction
  • C10C3/04—Working-up pitch, asphalt, bitumen by chemical means reaction by blowing or oxidising, e.g. air, ozone

Definitions

• the present invention relates to a process for the preparation of bitumens for road use, particularly with high performance characteristics.
• bitumens for road use can be obtained from fractions coming from different refinery processes such as distillation (atmospheric and vacuum), visbreaking and thermal cracking, reconstruction (for example with LUBE cycle aromatic components).
• bitumen derives from each of these processes, generally having the following particular aspects:
• Bitumens for road use from distillation, thermal cracking (visbreaking) and reconstruction indicatively have the characteristics shown in table 2.
• Unit Dist. Visbr. Recon. Penetration at 25°C dmm 80/100 80/100 80/100 Ring & Ball °C 44/48 44/48 42/46 Fraass Breakingpoint °C -12/-16 -14/-18 -10/-14 Pen. at 25°C after T.L init % 50/60 35/45 60/70 Increase in Ring & °C 5/10 8/15 3/5 Ball after T.L. Viscosity at 60°C Pa.sec 100/200 70/120 110/150
• US-A-3,440,074 discloses a process for the preparation of bitumens for road use, comprising the oxidation of a composition consisting of a bituminous component (I) and an aromatic component (II), the bituminous component (I) being a vacuum residue from Middle East crude petroleums.
• the present invention relates to a process for the preparation of bitumens for road use, characterized in that it comprises the oxidation of a composition consisting of:
• the oxidation takes place at a temperature of between 150°C and 270°C, more preferably from 160°C to 250°C, even more preferably from 170°C to 190°C.
• the above oxidation is carried out with oxygen diluted with an inert gas, preferably with air.
• the oxidation is carried out on compositions of (I) and (II) previously prepared. According to another embodiment, the oxidation is carried out contemporaneously with the mixing of the two components (I) and (II).
• bituminous component (I) is the vacuum residue obtained by distillation at reduced pressure of the effluent of the visbreaking plant.
• a typical example of aromatic compound (II) is the aromatic fraction, extracted by a solvent extraction process, of the vacuum distillate or deasphalted vacuum residue, in an operating cycle for the production of lubricating bases. These fractions shall hereafter be abbreviated with the initials CA. Table B shows the characteristics of some of these fractions.
• the above table B also indicates the characteristics of some samples of vacuum gas oils obtained by vacuum distillation of the effluent of a visbreaking plant. These samples (called GVB) cannot be used in the process of the present invention as they do not have the required characteristics of the bituminous component (I) or the aromatic component (II). They are specified here because they shall be used further on in the comparative examples.
• GVB 1-3 CA 1-2 Viscosity at 60°C (cSt) 34.5-31.9-36.4 305-257 Asphaltenes (w %) 0-0-0 0-0 Saturated products (w %) 48.5-41.8-50.6 2.7-0.9 Resins (w %) 14.5-7.3-8.3 12.2-12.5 Aromatics (w %) 37.0-50.9-41.1 85.1-86.6
• bituminous component (I) and aromatic component (II) this depends on the characteristics of the two components and of the bitumen to be obtained. In any case it must be within the range indicated above.
• the duration of the process of the present invention depends on the various parameters, for example temperature, stirring rate, viscosity of the components.
• the duration is usually from a few tens of minutes to several hours.
• the process of the present invention allows the production of a road bitumen capable of satisfying the specifications indicated above which will be shortly introduced in Europe.
• the bitumen for road use obtained with the process of the present invention has a good consistency when hot, an excellent flexibility when cold and a high resistance to oxidation.
• a road visbreaking bitumen is prepared, by simple mixing (consequently without oxidation) of RVB1 and GVB1.
• the mixing is carried out at 130/150°C by stirring for 20/30 minutes with a slanting blade stirrer at a rate of about 400 revs/minute.
• the bitumen (which we shall call 1C) has the properties indicated in table 1C, which also give the CNR and CEN specification values. Specifications RVB1 content 90% w CNR CEN GVB1 content 10% w Penetration at 25°C 90 dmm 80/100 70/100 Ring & Ball 47°C 44/49 43/51 Fraass breakingpoint -18°C ⁇ -10°C ⁇ -10°C Penetr. after T.L. 41% -- ⁇ 46% Increase Ring & Ball after T.L. 14.5°C -- ⁇ 9°C Viscosity at 60°C 80 Pa.sec -- ⁇ 90
• this bitumen proves to have a poor consistency when hot (viscosity value outside the limit) and a low resistance to oxidation (the values after the thin layer accelerated aging test are outside the limit).
• a road bitumen is prepared by the simple mixing of the bituminous component RVB1 and the aromatic component CA1.
• the bitumen (which we shall call 2C) has the properties indicated in table 2C, which also indicates the CNR and CEN specification values.
• Specifications RVB1 content 88.5% CNR CEN CA1 content 11.5% Penetration at 25°C 88 dmm 80/100 70/100 Ring & Ball 48°C 44/49 43/51 Fraass breakingpoint -17°C ⁇ -10°C ⁇ -10°C Penetr. after T.L. 45% -- ⁇ 46% Increase Ring & Ball 11°C -- ⁇ 9°C after T.L. Viscosity at 60°C 69 Pa.sec -- ⁇ 90
• bitumen 2C although indicating (with respect to the bitumen 1C) a good improvement in the characteristics after the thin layer accelerated aging test, is still outside the specification values, particularly with respect to the high temperature characteristics (viscosity at 60°C).
• the percentage of aromatic component is increased in an attempt to further improve the characteristics of the end-product.
• bitumen consisting of 60% by weight of RVB1 and 40% by weight of CA1 is prepared.
• the bitumen thus obtained has a penetration at 25°C of about 800 dmm, against a CNR specification of 80/100 and CEN specification of 70/100.
• the bitumen thus obtained is therefore clearly outside the regulation values as an initial penetration value.
• This example describes the preparation of a road bitumen obtained by the mixing of two components from visbreaking (RVB1 and GVB1) and subsequent blowing with air at 250°C.
• the two components are mixed in a metal container heated to 130/150°C by stirring for 20/30 minutes with a blade stirrer (about 600 revs/minute). During this period the temperature is increased to about 250°C. Air is blown into the mixture thus heated and stirred at a flow-rate of about 90 litres/hour per kg of mixture.
• bitumen 3C is still outside the specification values with respect to resistance to oxidation (in particular the value of increase in Ring & Ball after the thin layer accelerated aging test), and as consistency at high temperature (viscosity value).
• a road bitumen is prepared by the air blowing of a composition consisting of a component from visbreaking (RVB1) and an aromatic component (CA1).
• the two components are mixed in a metal container heated to 130/150°C by stirring for 20/30 minutes with a blade stirrer (about 600 revs/minute). During this period the temperature is increased to about 250°C. Air is blown into the mixture thus heated and stirred at a flow-rate of about 90 litres/hour per kg of mixture.
• bitumen 4 The characteristics of this bitumen called bitumen 4, are shown in table 4. Specifications RVB1 content 60.0% CNR CEN CA1 content 40.0% Penetration at 25°C 90 dmm 80/100 70/100 Ring & Ball 47°C 44/49 43/51 Fraass breakingpoint -23°C ⁇ -10°C ⁇ -10°C Penetr. after T.L. 56% -- ⁇ 46% Increase Ring & Ball after T.L. 8°C -- ⁇ 9°C Viscosity at 60°C 121 Pa.sec -- ⁇ 90
• bitumen of example 4 is perfectly in accordance with all the specifications, with distinctly improved overall characteristics compared to the comparative bitumens described above.
• bitumen 4 prepared according to the process of the present invention, has a good consistency when hot, an excellent flexibility when cold and a high resistance to oxidation.
• the formulation is provided of a road bitumen from visbreaking obtained by the simple mixing of two components from visbreaking (RVB2 and GVB2), in accordance with the normal refinery procedure.
• the process is the same as that previously described in example 1.
• bitumen has a very poor resistance to oxidation with values after the thin layer accelerated aging test which are clearly outside the regulation values.
• a road bitumen is prepared by the simple mixing of a component from visbreaking (RVB2) and an aromatic component (CA1).
• a composition of bitumen is prepared starting from the same components as comparative example 6, but in a different ratio.
• bitumen is prepared, according to the procedure described in example 1, consisting of 60% by weight of RVB2 and 40% by weight of CA1.
• the bitumen thus obtained has a penetration at 25°C of about 700 dmm, against a CNR specification of 80/100 and CEN specification of 70/100. This bitumen is therefore clearly outside the regulation value as initial penetration value.
• This example describes the formulation of a road bitumen from visbreaking obtained by the mixing of two components from visbreaking (RVB2 and GVB2), with subsequent blowing with air at 250°C, according to the procedure of example 4.
• bitumen 7C thus prepared are indicated in table 7C.
• Specifications RVB2 content 78% CNR CEN GVB2 content 22% Penetration at 25°C 88 dmm 80/100 70/100 Ring & Ball 52°C 44/49 43/51 Fraass breakingpoint -26°C ⁇ -10°C ⁇ -10°C Penetr. after T.L. 47% -- ⁇ 46% Increase Ring & Ball after T.L. 21.5°C -- ⁇ 9°C Viscosity at 60°C 131 Pa.sec -- ⁇ 90
• bitumen still has a very poor resistance to oxidation (in particular as an increase in the Ring & Ball softening point value after the thin layer accelerated aging test)
• the formulation is provided of a road bitumen obtained by the mixing of a component from visbreaking (RVB2) and an aromatic component (CA1), with subsequent blowing with air at 170°C.
• RVB2 component from visbreaking
• CA1 aromatic component
• bitumen 8 thus obtained are indicated in table 8. Specifications RVB2 content 70% CNR CEN CA1 content 30% Penetration at 25°C 82 dmm 80/100 70/100 Ring & Ball 49°C 44/49 43/51 Fraass breakingpoint -25°C ⁇ -10°C ⁇ -10°C Penetr. after T.L. 67% -- ⁇ 46% Increase Ring & Ball after T.L. 5.5°C -- ⁇ 9°C Viscosity at 60°C 153 Pa.sec -- ⁇ 90
• bitumen 8 thus prepared is perfectly in line with the above specifications, with clearly improved overall characteristics with respect to those of the bitumens described in the previous comparative examples.
• a road bitumen is prepared by mixing and subsequently subjecting to blowing with air at 180°C a composition of bituminous component (RVB3) and an aromatic component (CA2).
• RVB3 bituminous component
• CA2 aromatic component
• Specifications RVB3 content 70.0% CNR CEN CA2 content 30.0% Penetration at 25°C 89 dmm 80/100 70/100 Ring & Ball 47.5°C 44/49 43/51 Fraass breakingpoint -21°C ⁇ -10°C ⁇ -10°C Penetr. after T.L. 63% -- ⁇ 46% Increase Ring & Ball after T.L. 4.5°C -- ⁇ 9°C Viscosity at 60°C 102 Pa.sec -- ⁇ 90
• bitumen is perfectly in line with the specification values indicated above.
• the formulation is provided of a road bitumen obtained, according to the procedure of example 4, by mixing RVB3 and CA2 and subsequently blowing with air at 190°C.
• bitumen 10 The characteristics of this bitumen (bitumen 10) are indicated in table 10. Specifications RVB3 content 80.0% CNR CEN CA2 content 20.0% Penetration at 25°C 83 dmm 80/100 70/100 Ring & Ball 48°C 44/49 43/51 Fraass breakingpoint -19°C ⁇ -10°C ⁇ -10°C Penetr. after T.L. 54% -- ⁇ 46% Increase Ring & Ball after T.L. 7°C -- ⁇ 9°C Viscosity at 60°C 130 Pa.sec -- ⁇ 90
• this one has a good consistency when hot, an excellent flexibility when cold and a high resistance to oxidation.

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• Chemical & Material Sciences (AREA)
• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Road Paving Structures (AREA)
• Working-Up Tar And Pitch (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

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• 1997
  • 1997-03-06 IT IT97MI000492A patent/IT1290566B1/it active IP Right Grant
• 1998
  • 1998-03-05 PT PT98200671T patent/PT863196E/pt unknown
  • 1998-03-05 EP EP98200671A patent/EP0863196B1/en not_active Expired - Lifetime
  • 1998-03-05 ES ES98200671T patent/ES2181118T3/es not_active Expired - Lifetime
  • 1998-03-05 DK DK98200671T patent/DK0863196T3/da active
  • 1998-03-05 SI SI9830256T patent/SI0863196T1/xx unknown
  • 1998-03-05 AT AT98200671T patent/ATE221112T1/de not_active IP Right Cessation
  • 1998-03-05 DE DE69806659T patent/DE69806659T2/de not_active Expired - Lifetime
  • 1998-03-06 TR TR1998/00408A patent/TR199800408A2/xx unknown

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