WO2000014161A1

WO2000014161A1 - Bitumen emulsion with controlled viscosity, emulsifying agent composition and preparation method

Info

Publication number: WO2000014161A1
Application number: PCT/FR1999/002081
Authority: WO
Inventors: Graziella Durand; Jean-Eric Poirier
Original assignee: Colas
Priority date: 1998-09-02
Filing date: 1999-09-01
Publication date: 2000-03-16
Also published as: FR2782724B1; CA2309291A1; FR2782724A1; EP1040167A1

Abstract

The invention concerns a bitumen emulsion with controlled viscosity comprising a first type of cationic emulsifier and a second type of non-ionic emulsifier and an included water fraction ranging between 1 and 15 % of the total water. The emulsion is stable in time owing to the presence of an emulsifying layer at each of the oil-in-water and water-in-oil interfaces. The resulting emulsion can be used for road surfacing. The invention also concerns an emulsifying agent composition and a method for making bitumen emulsion.

Description

BITUMEN EMULSION WITH CONTROLLED VISCOSITY, COMPOSITION OF EMULSIFYING AGENTS AND MANUFACTURING METHOD

The invention relates to a bituminous emulsion with controlled viscosity, a composition of emulsifying agents and a method of manufacturing a bituminous emulsion. It has applications in the production of bitumen-based emulsions, for use in road techniques, civil engineering or in industrial jobs.

The use of bitumen emulsions for the production of road surfaces is well known. The implementation, for this purpose, is currently done by spreading or coating. Before use, these emulsions must be able to be stored in tanks. So that the implementation of the emulsion is done in good conditions, in particular to avoid that run-offs on declivity roads, assembly roads for example, or simply curved, cause a spill of the emulsion on the bottoms sides or do not cause inhomogeneities of the coating and also so that storage can be done over long periods without risk of sedimentation of the emulsion particles and without the need for agitation of the emulsion, the viscosity of the bituminous emulsion must be high enough.

In addition, standards have been defined and specifications may be required by the contracting authorities with regard to the viscosity of the bituminous emulsion. It is therefore necessary to be able to control it. There are four known means that can be used to act on viscosity: increasing the bitumen content, adding a viscosifier, adding salts to the bitumen and controlling the particle size of the emulsion. However, these various means have limitations:

The increase in the bitumen content is not economically attractive. On the other hand, beyond a certain concentration of bitumen, manufacturing becomes difficult and it is in practice necessary to work under pressure. In addition, the bitumen concentration specifications which are often imposed limit the possibilities of acting on this parameter.

The addition of a viscosifier leads to an increase in costs and its effect is not permanent since the viscosity tends to decrease during time. Furthermore, most effective viscosifiers are in solid form and are therefore difficult to use in manufacturing facilities. Such a technique is for example described in document EP-425,380 which proposes an emulsion of bituminous binder with viscosity controlled by addition of scleroglucan.

The addition of salts in bitumens seems interesting because of a relatively reduced cost. However, the effect produced is transient because osmotic phenomena develop over time and cause a change in viscosity. On the other hand, it is not possible to increase the amount of salt in the bitumen without adversely affecting the use properties of the bituminous emulsion. Document FR-2,665,709, for example, describes the use of a metal salt in a bitumen emulsion.

Finally, the action on the particle size of the emulsion consists in reducing the size of the particles. The finer and more monodispersed the particles, the higher the viscosity of the emulsion. This action is limited by the mechanical constraints imposed by the majority of the manufacturing materials usually used. Document EP-283,246 describes such a process for preparing bitumen emulsion.

The object of the present invention is to propose means allowing the production of a bituminous emulsion having a high and controlled viscosity without the above-mentioned drawbacks.

To this end, the invention relates to a bituminous emulsion with controlled viscosity comprising an organic phase, oil type and an aqueous phase, water type and emulsifying agents in which the following means are used, said means being able to be combined in various embodiments technically possible:

- A first type of emulsifier promotes the oil-in-water type emulsion.

- A second type of emulsifying agent promotes the emulsion type water in oil. - The organic phase forms particles within the aqueous phase, said particles can include within them one or more aqueous phases, the fraction of water included being between 1% to 15% of the total water. - the first type of emulsifying agent is cationic.

- the second type of emulsifying agent is non-ionic.

- the cationic emulsifying agent is chosen from alkyl diamine salts, alkyl polyamine salts, alkylpolyaminoamide salts, quaternary ammonium salts with a fatty chain, etc. - the nonionic emulsifying agent is chosen from the family of ethoxylated fatty alcohols, the hydrophobic part of the molecule can be of the nonylphenol-, octylphenol-, cetyl, oleic type, the hydrophilic part consisting of several ethoxy groups.

- The emulsion may also contain one or more acids. - The emulsion may also contain one or more salts.

The invention relates to a composition of emulsifying agents in which the following means are used to control the viscosity of bituminous emulsions comprising a fraction of water included between

1% to 15% of the total water, said means being able to be combined in various technically possible embodiments:

- The composition of emulsifying agents comprises a cationic agent and a nonionic agent.

the cationic agent is chosen from alkyl diamine salts, alkyl polyamine salts, alkylpolyaminoamide salts, quaternary ammonium salts with a fatty chain, etc.

the nonionic agent is chosen from the family of ethoxylated fatty alcohols, the hydrophobic part of the molecule possibly being of the nonylphenol-, octylphenol-, cetyl, oleic type, etc., the hydrophilic part consists of several ethoxy groups. - The composition may also contain one or more acids. - The composition may also contain one or more salts. The invention relates to a process for manufacturing bituminous emulsion with controlled viscosity, in which the following means are used, said means being able to be combined in various technically possible embodiments:

- The manufacturing process includes the following steps: a first aqueous phase comprising water, one or more cationic emulsifiers, which may comprise one or more soluble nonionic emulsifiers, is carried out; a second heated anhydrous phase, which may include one or more nonionic emulsifiers, is carried out; the two phases are introduced into a colloid mill, the fraction of water included is between 1% to 15% of the total water.

the cationic emulsifiers are chosen from alkyl diamine salts, alkyl polyamine salts, alkylpolyaminoamide salts, quaternary ammonium salts with a fatty chain, the nonionic emulsifiers are chosen from the family of ethoxylated fatty alcohols, the hydrophobic part of the molecule being able to be of nonylphenol-, octylphenol-, cetyl, oleic type ..., the hydrophilic part consists of several ethoxy groups. The present invention will be better understood on reading examples of implementation and comparison with the state of the prior art. A comparative table between various formulations of the prior art and according to the invention for various emulsion parameters is given in the appendix.

A first emulsion A, of known type, is produced, it is a cationic bitumen emulsion of a conventional type, the bitumen level, grade 180/220, is 69% and the cationic emulsifier is a dodecylamine at a concentration of 65 mmol / l of aqueous phase, hydrochloric acid being added for salification.

A second emulsion B, of known type, is produced, it is an emulsion of non-ionic bitumen, the bitumen rate, grade 180/220, is 69%, and the nonionic emulsifier of the 25 mole ethoxylated cetostearyl alcohol type is at a concentration of 30 mmol / l of aqueous phase.

A third emulsion C is produced, it is an emulsion of bitumen, of the mixed cationic and nonionic type according to the invention, the level of bitumen, grade 180/220, is 69%, the cationic emulsifier is a dodecylamine with a concentration of 50 mmol / l of aqueous phase, the salification being obtained with hydrochloric acid, and a nonionic emulsifier of the ethoxylated cetostearyl alcohol type at 25 moles is at a concentration of 20 mmol / l of aqueous phase. A fourth emulsion D is produced, it is an emulsion of bitumen, mixed cationic and nonionic emulsion according to the invention, the bitumen content, grade 180/220, is 69%, the cationic emulsifier being a dodecylamine is at a concentration of 50 mmol / l of aqueous phase, the salification being obtained with hydrochloric acid, and a nonionic emulsifier of the ethoxylated cetostearyl alcohol type at 25 moles is at a concentration of 30 mmol / l of aqueous phase.

Of these four bituminous emulsions, five measurements were made.

- a sieve rejection measurement of 630 μm according to standard NF T 66 016.

- a measurement of the median diameter of the particles by measurement by laser granulometry.

- a measurement of the rupture index of the cationic emulsion according to standard NF T 66 017 (IREC) and which corresponds to the quantity of fine silica resulting in the rupture of 100 g of cationic bitumen emulsion. It is generally considered that a fast-breaking emulsion usually has an IREC <80.

- a measurement of the adhesion of the cationic emulsion according to standard NF T 66 018, the results being discretized.

- a viscosity measurement at 25 ° C by BROOKFIELD equipment.

On reading the table shown in the appendix, it can be seen that the weakly viscous control emulsion A has good characteristics. breaking and adhesiveness. The control emulsion B is viscous but not very adhesive. Emulsions C and D have very good characteristics resulting from the combination of properties linked to the cationic and nonionic characteristics of the emulsion: adhesiveness, rapid rate of rupture of the emulsion, high viscosity. The characteristics are therefore much superior to the simple addition of the results produced independently by the emulsifiers.

ANNEX

Claims

1. Bituminous emulsion with controlled viscosity comprising an organic phase, oil type and an aqueous phase, water type and emulsifying agents, characterized in that a first type of emulsifying agent promotes the emulsion type oil in water and that a second type of emulsifier promotes water-in-oil type emulsion, the organic phase forming particles within the aqueous phase, said particles being able to include within them one or more aqueous phases, the fraction of water included being included between 1% to 15% of the total water.

2. Emulsion according to claim 1, characterized in that the first type of emulsifying agent is cationic.

3. Emulsion according to claim 1 or 2, characterized in that the second type of emulsifying agent is nonionic.

4. Emulsion according to any one of the preceding claims, characterized in that the cationic emulsifying agent is chosen from alkyl diamine salts, alkyl polyamine salts, alkylpolyaminoamide salts, quaternary ammonium salts with fatty chain.

5. Emulsion according to any one of the preceding claims, characterized in that the nonionic emulsifying agent is chosen from the family of ethoxylated fatty alcohols, the hydrophobic part of the molecule being able to be of nonylphenol-, octylphenol-, cetyl type, oleic, and the hydrophilic part consisting of several ethoxy groups.

6. Emulsion according to any one of the preceding claims, characterized in that it can also contain one or more acids and that it can also contain one or more salts.

7. Composition of emulsifying agents, characterized in that it is used to control the viscosity of bituminous emulsions comprising a fraction of water included between 1% and 15% of the total water and comprising a cationic agent and an agent non-ionic.

8. Composition according to claim 7, characterized in that the cationic agent is chosen from alkyl diamine salts, alkyl polyamine salts, alkylpolyaminoamide salts, quaternary ammonium salts with a fatty chain, and that the nonionic agent is chosen from the family of ethoxylated fatty alcohols, the hydrophobic part of the molecule possibly being of the nonylphenol-, octylphenol-, cetyl or oleic type.

9. Composition according to claim 7 or 8, characterized in that it can also contain one or more acids and that it can also contain one or more salts.

10. A method of manufacturing bituminous emulsion with controlled viscosity, characterized in that a first aqueous phase comprising water, comprising one or more cationic emulsifiers, which may comprise one or more soluble nonionic emulsifiers, is carried out; that a second heated anhydrous phase, which may include one or more nonionic emulsifiers, is carried out; that the two phases are introduced into a colloid mill and that the fraction of water included is between 1% to 15% of the total water.

11. Manufacturing process according to claim 10, characterized in that the cationic emulsifiers are chosen from alkyl diamine salts, alkyl polyamine salts, alkylpolyaminoamide salts, fatty chain quaternary ammonium salts, and that the nonionic emulsifiers are chosen from the family of ethoxylated fatty alcohols, the hydrophobic part of the molecule possibly being of the nonylphenol-, octylphenol-, cetyl or oleic type.