Bituminous compositions comprising zeolite particles and trapped co2, and associated methods and uses

Abstract

The present invention relates to a bituminous composition, wherein the bitumen base represents at least 75% by weight relative to the total weight of the bituminous composition, the composition comprising a bitumen base and zeolite particles and being characterised in that the CO2 is trapped in the bituminous composition and represents from 0.2% to 3% by weight relative to the weight of the bitumen base and the zeolite particles represent from 0.1% to 10% by weight relative to the weight of the bitumen base. The invention also relates to a method for preparing compositions of this type and to the uses thereof, in particular for manufacturing coated materials or asphalts.

Description

Description Title of the invention: Bituminous compositions comprising zeolite particles and trapped CO2, associated processes and uses Technical Field

[0001] The present invention relates to the technical field of bitumen. More specifically, it relates to bituminous compositions capable of capturing CO2, and consequently, offering the possibility of reducing the amount of CO2 emitted into the atmosphere. The invention also relates to processes for preparing such compositions, as well as their uses in road construction and industry. Previous technique

[0002] CO2 is a greenhouse gas. Therefore, CO2 emissions into the atmosphere contribute to global warming. To promote sustainable development and reduce global warming, solutions are being sought to decrease the amount of CO2 released into the atmosphere. Methods for capturing CO2 produced by various human activities are therefore of great interest.

[0003] The applicant attempted to trap CO2 in bituminous compositions, but the tests carried out presented in the examples show that the CO2 tends to be released after trapping in the bitumen, and that there is a real challenge in being able to stabilize some of the CO2 that can be stored in the bitumen, so that the latter can at least be partially stored in the long term in the bitumen.

[0004] In this context, the applicant proposes new bituminous compositions that allow for the sustainable storage of CO2, processes for obtaining such compositions and their uses in road and industrial fields. Description of the invention

[0005] The invention relates to a bituminous composition comprising a bitumen base, zeolite particles, and CO2 trapped in said composition. bituminous. In particular, the captured CO2 represents 0.2 to 3% by mass (% mass), preferably 0.2 to 2% by mass, and preferably 0.2 to 0.8% by mass, of the mass of the bitumen base.

[0006] Within the scope of the invention, it has been observed that when zeolite particles are incorporated into a bituminous composition, the latter can then also include CO2 intentionally incorporated therein, without total release of the incorporated CO2, a portion of which remains trapped within the bituminous composition. The trapped CO2 represents, in particular, 0.2 to 3% by mass, preferably 0.2 to 2% by mass, and preferably 0.2 to 0.8% by mass, of the mass of the bitumen base of the bituminous composition.

[0007] In general, the trapped CO2 represents 0.2 to 2% by mass, preferably 0.2 to 1.5% by mass, and preferably 0.2 to 0.8% by mass, relative to the total mass of the bituminous composition.

[0008] Advantageously, the zeolite particles incorporated into the bituminous composition represent 0.1 to 10% by mass, preferably 1 to 8% by mass, and preferably 3 to 7% by mass, of the mass of the bitumen base of the bituminous composition.

[0009] In particular, in the bituminous compositions according to the invention, the zeolite particles are particles of a zeolite selected from among the faujasites, notably CBV 400, CBV 760 and 13X and LTA, preferably the zeolite is an LTA 5A. Even though the pore size of LTA zeolites is smaller, it has been observed in the examples that, by using such zeolites, and in particular the LTA 5A zeolite, it was possible to obtain more rapid stabilization of the amount of CO2 incorporated in the bituminous composition.

[0010] According to particular embodiments, the zeolite particles incorporated in the bituminous composition have a specific surface area determined according to the BET method of 20 to 600 g / m2, preferably of 50 to 400 g / m2.

[0011] In particular, within the scope of the invention, it has been observed that when zeolite particles are incorporated into a bitumen base, it is then possible to incorporate CO2 into the composition, and this with a certain Stability over time. Indeed, even though some CO2 tends to dissipate back into the atmosphere immediately after incorporation, this release ceases after a certain time, resulting in a stabilization of the mass of the resulting bituminous composition. Thus, the stability of the bituminous composition's mass reflects the fact that the amount of CO2 trapped within said composition is stabilized. The inventors have demonstrated, within the scope of the invention, that this stabilization occurs while a significant portion of the initially incorporated CO2 mass is still trapped within the bituminous composition. In the context of the invention, the terms "trapped CO2" and "incorporated CO2" are used interchangeably.Trapped or incorporated CO2 refers to CO2 that has been incorporated into the bituminous composition and remains present therein, particularly in its initial form, which has diffused within the bituminous composition. Regardless of the form in which the CO2 is present, in the context of this invention, when referring to the mass of CO2, this refers to the mass of incorporated CO2, even if the latter might be found in the bituminous composition in a form that has reacted with one of the other compounds present. In the context of this invention, when referring to trapped or incorporated CO2 in said bituminous composition, this refers specifically to CO2 originating from an external source, also called exogenous CO2.

[0012] Advantageously, the mass of the bituminous composition according to the invention is stable at 25°C and under 1013.25 hPa, over a period Ps (stability evaluation period). The period Ps shall preferably be at least 5 hours, preferably at least 10 hours, preferably at least 20 hours, and even more preferably at least 25 hours. Typically, the stability can be evaluated over a period Ps of 5 to 24 hours, and in particular 24 hours. The definition of the period Ps given above is valid throughout this description of the invention. The mass of the bituminous composition is considered stable over a given period Ps if this mass does not decrease by more than 2%, preferably by more than 1%, and preferably by more than 0.5%, and even more preferably by more than 0.05%, relative to the initial mass of the composition, that is, its mass at beginning of the period under consideration. The stability of a composition as it exists at a given instant t can therefore be evaluated by measuring its mass at that instant t, and then at instant t + the evaluation period Ps. In other words, the mass of a bituminous composition is considered stable if the mass m Ps the bituminous composition at the end of the evaluation period Ps (Ps=5 to 100 hours, in particular = 5 or 10 hours) is greater than or equal to its mass m o at the beginning of the evaluation period (t=0) - 2%, preferably greater than or equal to m0- 1%, greater than or equal to m0- 0.5%, and even more preferably greater than or equal to m0- 0.05%.

[0013] Within the scope of the invention, the mass stability of the bituminous composition is evaluated by leaving a bituminous composition at 25°C and under atmospheric pressure (i.e., at a pressure of 1013.25 hPa). Under these conditions, the atmosphere in which the bituminous composition is located has no influence. However, stability is typically evaluated under ambient air.

[0014] In particular, CO2 was trapped in the bituminous composition, following a trapping step, notably carried out by placing said bitumen base modified by incorporation of zeolite particles (called modified bitumen base), in a chamber under CO2 pressure, which may be followed by a step of releasing part of the trapped CO2, until the mass of the bituminous composition obtained stabilizes, this stabilization being able to occur immediately, or after a release step, notably 10 hours or more after the end of the trapping step, notably 15 to 30 hours after the end of the trapping step.

[0015] In particular, the incorporation of CO2 during this trapping step is carried out by placing the modified bitumen base incorporating zeolite particles in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 10 to 200 °C, preferably from 20 to 160 °C, and preferably from 25 to 160 °C, or even from 80 to 160 °C, the CO2 pressure being notably chosen in the range of 5.10 3 at 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa. The incorporation temperature influences the observed stability of the trapped CO2. In particular, the trapping is carried out until saturation of the CO2 composition. It was observed by the inventors that if the incorporation was done at a higher temperature, the stabilization of the CO2 could be immediate, whereas if the incorporation was done at lower temperatures, a release stage could occur.

[0016] In particular, according to a first implementation variant, the incorporation of CO2 is carried out by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 100 to 150 °C, typically equal to 120 °C, the QC pressure being notably chosen in the range of 5.10 3 at 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa and typically at a pressure equal to 2.1 x 10 4hPa. In this case, the stabilization of the trapped CO2 mass is immediate. In particular, trapping occurs until the CO2 composition is saturated.

[0017] According to a second implementation variant, the incorporation of CO2 is carried out by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature below 100 °C, in particular at a temperature belonging to the range of 20 to 50 °C, typically equal to 25 °C, the QC pressure being in particular chosen in the range of 5.10 3 at 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa and typically equal to 2.1 x 10 4hPa, and the bituminous composition resulting from this incorporation is then subjected to a release stage of some of the trapped CO2, after which the mass of the bituminous composition is stable. In particular, the trapping is carried out until the composition is saturated with CO2.

[0018] Regardless of the method of incorporation, once the mass of the bituminous composition has stabilized, it remains stable if the bituminous composition is maintained at 25°C and under atmospheric pressure. Typically, within the scope of the invention, bituminous compositions, comprising a bitumen base into which zeolite particles have been incorporated, have a mass that is stable at 25°C and under 1013.25 hPa, over a period Ps. In other words, over the period Ps, the mass of the composition does not decrease by more than 2%, preferably not by more than 1%, and preferably not by more than 0.5%, and even more Preferably, the mass does not decrease by more than 0.05% relative to the initial mass of the composition at the beginning of the considered period Ps. A bituminous composition according to the invention has a stable mass, while containing a quantity of CO2 that has been incorporated into the bituminous composition and remains trapped within said bituminous composition. This quantity of CO2, which can be described as stabilized, represents 0.2 to 3% by mass, preferably 0.2 to 2% by mass, and preferably 0.2 to 0.8% by mass, of the mass of the bitumen base. The quantity of CO2 can be determined by weighing.

[0019] Within the scope of the invention, masses can be determined by weighing, using a precision balance, in particular to the nearest 0.0001 g (for example, a Sartorius Practum 224-1 S balance). In particular, the weighings are carried out at 25 °C and under atmospheric pressure (1013.25 hPa).

[0020] The bituminous compositions according to the invention can be obtained by placing a base bituminous composition (which comprises one or more bitumens as a bitumen base, zeolite particles, and possibly one or more other constituents) under CO2 pressure. The base bituminous composition preferably comprises all the components of the desired bituminous composition, except for CO2. In particular, the incorporation of CO2 is carried out by placing such a base bituminous composition in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 10 to 200 °C, preferably from 20 to 160 °C, and preferably from 25 to 160 °C, or even from 80 to 160 °C, the CO2 pressure being notably chosen in the range of 5.10 3 at 8.10 4 hPa (equivalent to 5-80 bar), preferably in the range of 5-10 3 at 5.10 4hPa (equivalent to 5-50 bar), and preferably in the range of 1.10 4 at 3.10 4 hPa (equivalent to 10⁻³⁰ bar). The mass of CO₂ incorporated into a bituminous composition corresponds to the difference between the mass of said bituminous composition and the mass of the same original bituminous composition. The mass of CO₂ incorporated can be tracked over time by monitoring the mass of the bituminous composition. Following the CO₂ capture stage, particularly if capture is carried out until the composition is saturated with CO₂, as explained previously depending on the temperature used during the capture stage, when the composition The resulting bituminous mixture, containing trapped CO2, is then stored at 25°C and under atmospheric pressure. During this time, a release of some of the incorporated CO2 may occur, resulting in a loss of mass in the composition. This release, if it takes place, ceases, even though some CO2 remains trapped within the bituminous mixture. This stabilization of the CO2 incorporated into the bituminous mixture is manifested by a stabilization of the bituminous mixture's mass. It is, in particular, these stabilized bituminous mixtures that are the subject of the invention.

[0021] Thus, the period Ps over which the mass of the bituminous composition according to the invention is stable can start immediately after the CO2 trapping step, or after a release phase Pr, during which part of the trapped CO2 is released from the bituminous composition.

[0022] This release phase Pr occurs, in particular, if the CO2 trapping step is carried out at a temperature below 100 °C, specifically at a temperature within the range of 20 to 50 °C, typically at 25 °C, and especially when using the previously mentioned CO2 pressure. The release phase Pr is most often at least 10 hours, and typically 15 to 30 hours, after the end of the CO2 trapping step. The definition of the period Ps given above is valid for the entirety of this description of the invention. The end of the CO2 trapping step corresponds, in particular, to the moment when the bituminous composition is no longer under CO2 pressure. During this release phase Pr following the CO2 trapping stage, the bituminous composition can be placed at 25°C and under a pressure of 1013.25 hPa.It is also possible that the bituminous composition is subjected to heating during this release phase Pr, which will accelerate the release of some of the CO2 and thus reduce the duration of the release phase. Once the release phase Pr is complete, the remaining CO2 remains trapped within the bituminous composition under standard storage conditions (at 25 °C and 1013.25 hPa), resulting in a stabilization of the bituminous composition's mass. The mass of the bituminous composition is understood to be the mass of all the components present (in particular the bitumen base, zeolite particles, and any other components that may be present). but also CO2 trapped in the bituminous composition when its mass is measured.

[0023] Thus, within the scope of the invention, it has been observed that the incorporation of zeolite particles into a bituminous composition allows for the permanent trapping of a quantity of CO2 within said bitumen composition. In particular, the incorporation of zeolite particles into a bituminous composition precedes the CO2 trapping step. Surprisingly, within the scope of the invention, it has been demonstrated that the zeolite particles, although trapped within the bituminous composition, possess a CO2 trapping capacity.

[0024] Furthermore, other bituminous compositions incorporating other components known to be porous and gas-absorbing, such as clays (notably described in application WO 2019 / 122670), do not allow for satisfactory CO2 capture. The tests presented in the examples showed that, in this case, CO2 release, after capture, occurred over a long period.

[0025] Thus, the invention offers compositions that allow sufficient CO2 storage to be of interest in the fight against the greenhouse effect and global warming, and that are satisfactory in terms of performance, making them usable in road and industrial application areas.

[0026] According to another of its objects, the invention relates to a process for preparing a bituminous composition comprising the following successive steps: a) obtaining a modified bitumen base, comprising the incorporation of zeolite particles into a bitumen base, said incorporation being followed or accompanied by mixing, preferably under heating at a temperature in the range of 90 to 230 °C, preferably in the range of 120 to 200 °C, and preferably in the range of 120 to 180 °C, b) trapping CO2 in the modified bitumen base at a mass content representing, in particular, 0.4 to 6% by mass, preferably 0.4 to 4% by mass, and preferably 0.4 to 2% by mass, and even more preferably 0.6 to 1.5% by mass, of the mass of the bitumen base.

[0027] Alternatively, the invention relates to a process for preparing a bituminous composition comprising the following successive steps: a) obtaining a modified bitumen base, comprising incorporating zeolite particles into a bitumen base, said incorporation being followed or accompanied by mixing, preferably under heating at a temperature in the range of 90 to 230 °C, preferably in the range of 120 to 200 °C, and preferably in the range of 120 to 180 °C; b) trapping CO2 in the modified bitumen base at a mass content of 0.2 to 6% by mass, preferably 0.2 to 4% by mass, and preferably 0.2 to 2% by mass, and more preferably 0.2 to 1.5% by mass, of the mass of the bitumen base.

[0028] The invention also relates to a process for preparing a bituminous composition comprising the following successive steps: a) obtaining a modified bitumen base, comprising the incorporation of zeolite particles, said incorporation being followed or accompanied by a mixture, preferably under heating to a temperature in the range of 90 to 230 °C, preferably in the range of 120 to 200 °C, and preferably in the range of 120 to 180 °C; b) trapping CO2 in the modified bitumen base until saturation with CO2.

[0029] In particular, in the processes according to the invention, the incorporation / trapping of CO2 is carried out by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 10 to 200 °C, preferably from 20 to 160 °C, and preferably from 25 to 160 °C, or even from 80 to 160 °C, the CO2 pressure being notably chosen in the range of 5.10 3 at 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa.

[0030] According to a first embodiment, CO2 trapping is achieved by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 100 to 150 °C, typically equal to 120 °C, the QC pressure being notably chosen in the range of 5.10 3 at 8.10 4hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa and typically equal to 2.1 x 10 4 hPa. In such a case, the amount of CO2 trapped in the resulting composition is immediately stabilized.

[0031] According to a second embodiment, CO2 trapping is achieved by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature below 100 °C, in particular at a temperature in the range of 20 to 50 °C, typically equal to 25 °C, the CO2 pressure being in particular chosen in the range of 5.10 3 at 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa and typically equal to 2.1 x 10 4hPa, the bituminous composition from step b) is then subjected to a release step of part of the trapped CO2, at the end of which the mass of the bituminous composition is stable and / or the quantity of CO2 trapped in the composition obtained is stabilized.

[0032] Advantageously, in the processes according to the invention, in step a), the mass of zeolite particles incorporated represents from 0.1 to 10% by mass, preferably from 1 to 8% by mass, and preferably from 3 to 7% by mass, of the base bitumen mass.

[0033] Furthermore, preferably, when obtaining the modified bitumen base, the mixture is carried out under agitation of 100 to 1000 rpm (revolutions per minute), preferably 100 to 600 rpm, and preferably 150 to 500 rpm and / or with an agitation time greater than or equal to 1 hour, in particular 1 to 5 hours.

[0034] According to particular embodiments of the processes according to the invention, in step a), one or more polymers chosen from olefinic polymers and elastomers, in particular from crosslinkable elastomers, is / are also incorporated into the bitumen base, said polymer(s) preferably being introduced at a rate of 0.1 to 12% by mass, preferably 0.3 to 10% by mass, and preferably 0.5 to 7% by mass, of the mass of the bitumen base.

[0035] In particular, said release step when present, or more generally the process according to the invention in the end, leads to a quantity of CO2 trapped in the bituminous composition, representing 0.2 to 3% by mass, of preferably 0.2 to 2% by mass, and preferably 0.2 to 0.8% by mass, of the mass of the bitumen base.

[0036] The invention also relates to bituminous compositions that can be obtained according to the processes of the invention, regardless of their embodiment variant.

[0037] In the compositions according to the invention, regardless of the embodiment variant, the bitumen base represents at least 75% by mass, preferably at least 80% by mass and preferably at least 85% by mass of the total mass of the bituminous composition.

[0038] The bituminous compositions according to the invention have various applications. Therefore, the invention also aims to: - the use of a bituminous composition according to the invention, to prepare a waterproofing coating, a membrane or an impregnation layer; as well as the processes for preparing such a waterproofing coating, such a membrane or such an impregnation layer; - bituminous binders comprising a bituminous composition according to the invention; - the use of a bituminous composition according to the invention, as a bituminous binder in a bituminous mix comprising a bituminous composition according to the invention, aggregates, and possibly mineral and / or synthetic fillers; as well as the processes for preparing such a bituminous mix; - the use of a bituminous composition according to the invention, as a bituminous binder in an asphalt comprising a bituminous composition according to the invention, and mineral and / or synthetic fillers; as well as the processes for preparing such an asphalt; - as well as the use of a bituminous composition according to the invention, as a bituminous binder in a surface dressing, hot mix asphalt, cold mix asphalt, cold poured asphalt, emulsion aggregate or wearing course, which comprises a bituminous composition according to the invention, aggregates and / or recycled millings; as well as the processes for preparing such a surface dressing, hot mix asphalt, cold mix asphalt, cold poured asphalt, emulsion aggregate or wearing course.

[0039] In one particular aspect, the invention relates to a process for preparing asphalt characterized in that it comprises the hot mixing of a bituminous composition according to the invention, or a composition obtainable according to a process of the invention, with mineral and / or synthetic fillers. Advantageously, the hot mixing with the bituminous composition can be carried out at a temperature of 80 to 200 °C, preferably 80 to 180 °C, and preferably 100 to 160 °C.

[0040] The invention also aims at the use of zeolite particles in a bituminous composition in which CO2 is incorporated, to obtain a stabilization of the amount of CO2 remaining trapped within said bituminous composition. Bitumen

[0041] The invention relates to compositions of bitumen modified by the addition of at least one additive or adjuvant, also called bituminous compositions. These may comprise one or more bitumens. The bitumen(s) present in the bituminous compositions according to the invention are called the "bitumen base" and constitute a major component of the composition, that is, represent at least 75% by mass of the total mass of the bituminous composition, and preferably at least 80%, or even at least 85% and even at least 90% by mass of the total mass of the bituminous composition. Among the bitumens usable according to the invention, we can first mention bitumens of natural origin, those contained in deposits of natural bitumen, natural asphalt, or oil sands, and bitumens obtained from crude oil refining.Within the scope of the invention, the bitumen(s) used are advantageously chosen from bitumens derived from crude oil refining, in particular bitumens containing asphaltenes or pitches. The bitumens can be obtained by conventional refining processes, particularly by direct distillation and / or vacuum distillation of petroleum. These bitumens may optionally be viscoreduced and / or deasphalted and / or air-rectified. It is common practice to perform vacuum distillation of atmospheric residues from the atmospheric distillation of crude oil. This manufacturing process therefore consists of a succession of atmospheric distillation and vacuum distillation. The feedstock for vacuum distillation consists of atmospheric residues. These vacuum residues from the vacuum distillation tower can also be used as bitumen. It is also common to inject air into a feedstock typically composed of distillates and heavy products from the vacuum distillation of atmospheric residues from petroleum distillation. This process yields blown, semi-blown, oxidized, air-rectified, or partially air-rectified bitumen. Different bitumens obtained through refining processes can be combined in the compositions according to the invention to achieve the best compromise in terms of technical performance.In conventional bituminous mixture manufacturing processes, production temperatures range from 90°C to 230°C, preferably from 120°C to 200°C, and agitation is carried out for a minimum of 10 minutes, preferably between 30 minutes and 10 hours, and more preferably between 1 and 6 hours. The manufacturing temperature refers to the heating temperature of the bitumen(s) before mixing with additives, as well as the mixing temperature. The heating temperature and duration vary depending on the quantity of bitumen used and are defined by standard NF EN 12594. Blown bitumen can be manufactured in a blowing unit by passing a flow of air and / or oxygen through a starting bitumen or bitumen mixture. This operation can be carried out in the presence of an oxidation catalyst, such as phosphoric acid.Generally, blowing is carried out at high temperatures, in the range of 200 to 300 °C, for relatively long periods typically between 30 minutes and 2 hours, either continuously or in batches. The duration and temperature of blowing are adjusted according to the desired properties of the blown bitumen and the quality of the starting bitumen.

[0042] Among the bitumens that can be used according to the invention, recycled bitumens can also be mentioned.

[0043] Bitumens can be hard grade bitumens (such as grades 10 / 20 and 20 / 30) or soft grade bitumens (such as grade 160 / 220) as defined by standard EN 12591.

[0044] The invention is particularly suitable for cases where the bitumen base consists of a hard grade bitumen or a mixture of hard grade bitumens, in particular chosen from grade 35 / 50, 20 / 30 and 10 / 20 bitumens.

[0045] The bitumen bases usable within the scope of the invention preferably have a penetrability, measured at 25°C according to standard EN 1426, of 5 to 330 1 / 10 mm, preferably between 10 and 220 1 / 10 mm, and more preferably between 10 and 120 1 / 10 mm. As is well known, the measurement known as "needle penetration" is carried out using a standardized test NF EN 1426 at 25°C (Pene). This penetrability characteristic is expressed in tenths of a millimeter (dmm or 1 / 10 mm). The needle penetration, measured at 25°C according to the standardized test NF EN 1426, represents the measurement of the penetration, after a time of 5 seconds, of a needle whose weight, including its holder, is 100 g into a sample of bitumen. Zeolite Particles

[0046] Zeolites are crystalline minerals composed of aluminosilicates of an alkali or alkaline earth metal. Zeolites exhibit a three-dimensional microporous or nanoporous structure with interconnected channels, the size of which varies depending on the structure. Zeolites can occur naturally or be modified or prepared. There are different types of zeolites: thirty-five natural zeolites and more than one hundred synthetic zeolites. Each type of zeolite is characterized by the architecture and size of its crystal lattice. All of them can be used within the scope of the invention.

[0047] Examples of zeolites particularly suitable for the purposes of the invention include A zeolites (also called LTA, for "Linde type A") and faujasites (also FAU). As shown in Figure 1, which represents the crystal structure of an FAU zeolite along the

[0111] axis, the structure of faujasite consists of an assembly of regular truncated octahedra (24 TO4 tetrahedra) called sodalite cages or O cages. Each of these cages is connected to four neighboring sodalite cages by means of double rings of six tetrahedra (right prisms with a hexagonal base, D6R). Figure 2 represents the crystalline structure of an LTA zeolite along the

[0111] axis and the elementary cages / structures that constitute it.

[0048] Examples of zeolite A include LTA 5A. Examples of faujasite include 13X, CBV 400 or CBV 700.

[0049] The specific surface area, determined by the BET (Brunauer, Emmell, and Teller) method, and the pore size of the zeolite particles used can be determined using the nitrogen adsorption and desorption isotherms at 77 K. The pore size of the zeolites can preferably be determined by the BJH (Barrett-Joyner-Halenda) method. For zeolite A, the pore size is 4.3 Å, and for faujasites, it is 7.4 Å.

[0050] Such zeolites are commercially available, notably from Sigma Aldrich.

[0051] Advantageously, the zeolite particles used, and in particular LTA 5A, faujasite 13X, CBV 400 or CBV 700 zeolite particles, have a BET surface area of ​​20 to 600 g / m² 2 , preferably 50 to 400 g / m 2 .

[0052] Advantageously, the introduced zeolite particles represent 0.1 to 10% by mass, preferably 1 to 8% by mass, and preferably 3 to 7% by mass, relative to the mass of the bitumen base present in the bituminous composition.

[0053] In general, the zeolite particles introduced represent 0.1 to 8% by mass, preferably 0.9 to 7% by mass, and preferably 2.7 to 6.5% by mass, relative to the total mass of the bituminous composition.

[0054] Within the scope of the invention, it has been demonstrated that the presence of such zeolite particles in the bituminous compositions according to the invention makes it possible to stabilize the mass of CO2 trapped in said compositions, and therefore the mass of said compositions as well. Stabilization occurs more rapidly, depending on the chosen temperature at which the CO2 is incorporated into the bituminous composition. Other possible components / additives

[0055] The bituminous compositions according to the invention may also include one or more polymers. In particular, an olefinic polymer and / or a elastomer, in particular a crosslinked or crosslinkable elastomer, may be incorporated into the bituminous compositions according to the invention.

[0056] The bituminous compositions according to the invention may, in particular, comprise one or more olefinic polymers, in particular selected from: (a1) statistical or sequenced copolymers, preferably statistical, of ethylene and a monomer selected from glycidyl acrylate and glycidyl methacrylate, comprising from 50% to 99.7% by mass, preferably from 60% to 95% by mass, more preferably 60% to 90% by mass of ethylene; (b1) statistical or sequenced terpolymers, preferably statistical, of ethylene, of a monomer A selected from vinyl acetate, C1-C6 alkyl acrylates and C1-C6 alkyl methacrylates and of a monomer B selected from glycidyl acrylate and glycidyl methacrylate; in particular said terpolymers comprising from 0.5% to 40% by mass, preferably from 5% to 35% by mass, more preferably from 10% to 30% by mass of motifs derived from monomer A and from 0.5% to 15% by mass, preferably from 2.5% to 15% by mass of motifs derived from monomer B, the remainder being formed from motifs derived from ethylene; (c1) copolymers resulting from the grafting of a monomer B selected from glycidyl acrylate and glycidyl methacrylate, onto a polymeric substrate; in particular the polymeric substrate is selected from polyethylenes, in particular low-density polyethylenes, polypropylenes, statistical or sequenced copolymers, preferably statistical, of ethylene and vinyl acetate and statistical or sequenced copolymers, preferably statistical, of ethylene and C1-C6 alkyl acrylate or C1-C6 alkyl methacrylate, comprising from 40% to 99.7% by mass, preferably from 50% to 99% by mass of ethylene; preferably said grafted copolymers comprising from 0.5% to 15% by mass, preferably from 2.5% to 15% by mass of grafted motifs from monomer B.

[0057] The bituminous compositions according to the invention may, in particular, comprise one or more elastomers, notably selected from crosslinked or crosslinkable elastomers. The crosslinked elastomers will be introduced in their crosslinkable form into the compositions according to the invention and crosslinked in situ. Such elastomers are known to be incorporated into a composition Bituminous copolymers include, in particular, SB (styrene-butadiene block copolymer), SBS (styrene-butadiene-styrene block copolymer), SIS (styrene-isoprene-styrene), SBS* (styrene-butadiene-styrene star block copolymer), SBR (styrene-butadiene-rubber), EPDM (modified ethylene propylene diene).

[0058] Advantageously, the mass of olefinic polymer(s) and / or elastomer(s) represents from 0.1 to 12% by mass, preferably from 0.3 to 10%, and preferably from 0.5 to 7% by mass, relative to the mass of the bitumen base present in the bituminous composition.

[0059] According to certain particular embodiments, a bituminous composition according to the invention comprises from 0.09% to 10% by mass, preferably from 0.3% to 8% by mass and preferably from 0.5% to 6% by mass, of olefinic polymer(s) and / or elastomer(s), relative to the total mass of said bituminous composition. Bituminous compositions, also known as bituminous compositions, according to the invention

[0060] Although it is not excluded that the bituminous compositions according to the invention may include one or more other additives, in particular chosen from those classically used in bituminous compositions, preferably the bitumen base, the trapped CO2, the zeolite particles, or even the elastomer(s) and / or olefinic polymer(s) represent at least 90% by mass, preferably at least 95% by mass, or even 100% by mass of the total mass of the bituminous composition.

[0061] The different components of the bituminous composition are dispersed in the bituminous composition, and therefore in the bitumen base.

[0062] Examples of particularly preferred bituminous compositions are given below. The preferred quantities of the various components present in the compositions according to the invention are given below. These quantities can be used independently of each other. Of course, they can also be used in combination, and all possible combinations of the ranges specified below are envisaged within the scope of the invention. By way of example, the widest mass percentage ranges given for each of the components can be used in combination, or the intermediate mass percentage ranges given for each component can be used in combination, or the most restricted mass percentage ranges given for each component can be used in combination.

[0063] In particular, the invention relates to bituminous compositions comprising a bitumen base modified by the incorporation of zeolite particles and in which CO2 has been incorporated and remains trapped. In other words, the invention relates to bituminous compositions comprising a bitumen base, zeolite particles, and trapped CO2.

[0064] In particular, such bituminous compositions comprise a bitumen base, modified by the incorporation of (or comprising): - 0.1 to 10% by mass, preferably 1 to 8% by mass, and preferably 3 to 7% by mass, relative to the base mass of bitumen, of zeolite particles, and in particular of particles of a zeolite chosen from among the faujasites, notably CBV 400, CBV 760 and 13X, and the LTA, preferably, the zeolite is an LTA 5A; - optionally, one or more polymers chosen from among olefinic polymers and elastomers, in particular from among crosslinked or crosslinkable elastomers, at a rate of 0.5 to 12% by mass, preferably from 0.3 to 10% by mass, and even more preferably from 0.5 to 7% by mass, of the mass of the bitumen base, - of CO2 trapped in the said composition, which represents 0.2 to 3% by mass, preferably 0.2 to 2% by mass, and preferably 0.2 to 0.8% by mass, relative to the mass of the bitumen base.

[0065] In such compositions, preferably, the polymer(s) present are chosen from those specifically described within the framework of this description.

[0066] It is possible for such compositions to include one or more other additives. However, it is preferable that the aforementioned components and the bitumen base constitute the bulk of the bituminous composition. In the bituminous compositions according to the invention, the bitumen base represents at least 75% by mass of the total mass of the bituminous composition, and preferably at least 80%, or even at least 85% and even at least 90% by mass of the total mass of the bituminous composition. This percentage will depend on the presence or absence of additional polymers, in particular. According to specific embodiments of the aforementioned bituminous compositions, the bitumen base may be modified only by the incorporation of the listed components.

[0067] Advantageously, these bituminous compositions will have a mass that remains stable at 25°C and under 1013.25 hPa, over a period Ps of at least 5 hours, preferably at least 10 hours. This stability criterion is as previously defined in this description. Preparation of bituminous compositions according to the invention and preparation method according to the invention

[0068] The bituminous compositions of the invention can be prepared using any method known to those skilled in the art for preparing bituminous compositions. Generally, these methods include mixing the components and heating the mixture. The bitumen may be heated before mixing. Usually, the bitumen is heated before mixing, and the additive(s) is / are added to the bitumen without having been preheated. According to a particular embodiment of the invention, a modified bitumen base is first prepared by contacting: - the bitumen base; - the desired mass of zeolite particles; - possibly one or more other additive(s).

[0069] Typically, the mixture of the bitumen base and zeolite particles, or even of the other additive(s) present, is carried out at temperatures ranging from 90 to 230 °C, preferably ranging from 120 to 200 °C, and preferably ranging from 120 to 180 °C.

[0070] Such a mixture is prepared under agitation, in particular, for a period of 5 minutes to 10 hours, preferably from 10 minutes to 3 hours, preferably from 10 to 90 minutes, and even more preferably from 20 to 90 minutes. The mixture can be prepared by means of agitation. producing high shear or low shear. In particular, the mixture is prepared under agitation at 100 to 1000 rpm (revolutions per minute), preferably 100 to 600 rpm, and preferably 150 to 500 rpm. Agitation is carried out in such a way as to facilitate the dispersion and even distribution of the zeolite particles in the bitumen base. A person skilled in the art will adjust the time and intensity of the agitation to obtain satisfactory distribution. It has been observed in examples that longer agitation times for preparing the modified bitumen base subsequently resulted in a greater quantity of CO2 trapped, both at the end of the trapping process and also after stabilization, if this is not immediate. Therefore, an agitation time of 1 hour or more, particularly 1 to 5 hours, during the preparation of the modified bitumen base is preferred.

[0071] When one or more polymers are incorporated into the bitumen base, they are preferably introduced before the zeolite particles, particularly for practical reasons. However, introduction after the zeolite particles could equally be implemented.

[0072] Advantageously, the incorporation of CO2 into the composition leading to its capture in the bituminous mixture is carried out after the zeolite particles have been incorporated. This maximizes the effect of the zeolite particles on CO2 capture. If one or more other components are incorporated, the incorporation of CO2 into the composition leading to its capture in the bituminous mixture is preferably carried out after the incorporation of the other components as well.

[0073] Such trapping can be achieved by placing the modified bitumen base containing the zeolite particles, and possibly the other additive(s), in a chamber pressurized with CO2. The chamber is maintained at a temperature generally ranging from 10 to 200 °C, preferably from 20 to 160 °C, and particularly from 25 to 160 °C. The CO2 pressure will be chosen in the range of 5.10 3 at 8.10 4 hPa (Hectopascal, corresponding to 5-80 bar), preferably in the range of 5-10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa. Maintenance under these conditions in the pressurized chamber will be ensured for a duration, most often of From 5 minutes to 100 hours. This duration will be adjusted by a person skilled in the art, depending in particular on the temperature chosen for CO2 incorporation, the CO2 pressure used, and the desired quantity of CO2. For example, CO2 incorporation will take place over a period of 5 to 50 hours when a temperature of 80 to 160 °C is used, and over a period of 30 minutes to 5 hours when a temperature of 10 to 40 °C is used, for the same pressure. The CO2 incorporation step can be carried out with or without mechanical agitation. If such agitation is present, the agitation speed can, for example, vary between 200 rpm and 6000 rpm (revolutions per minute).

[0074] CO2 incorporation is favored at lower temperatures. A person skilled in the art will be able to manipulate the three variables—temperature, pressure, and duration of exposure of the composition to CO2 pressure—to achieve optimal CO2 incorporation within the composition, and in particular, to achieve CO2 saturation. However, the stabilization of the CO2 concentration occurs more rapidly when incorporation is carried out at a higher temperature.

[0075] In general, after the CO2 capture step, the captured CO2 represents 0.4 to 6% by mass, preferably 0.4 to 4% by mass, and preferably 0.4 to 2% by mass, and more preferably 0.6 to 1.5% by mass, of the mass of the bitumen base. Alternatively, after the CO2 capture step, the captured CO2 represents 0.2 to 6% by mass, preferably 0.2 to 4% by mass, and preferably 0.2 to 2% by mass, and more preferably 0.2 to 1.5% by mass, of the mass of the bitumen base.

[0076] After such a CO2 trapping step, a release step of some of the trapped CO2 may occur, depending in particular on the temperature used during the CO2 trapping step.

[0077] Advantageously, CO2 trapping is achieved by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 100 to 150 °C, typically 120 °C, the CO2 pressure being notably chosen in the range of 5.10 3 has 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa and typically equal to 2.1 x 10 4 hPa. In this case, the stabilization of the trapped CO2 within the composition is immediate.

[0078] According to another implementation variant, CO2 trapping is achieved by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 20 to 50 °C, typically 25 °C, the QC pressure being notably chosen in the range of 5.10 3at 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa and typically equal to 2.1 x 10 4 hPa, the bituminous composition from step b) is then subjected to a release step of part of the trapped CO2, at the end of which the mass of the bituminous composition is stable.

[0079] The release phase (Pr), when present, generally lasts at least 10 hours, and most often 15 to 30 hours, after the end of the CO2 capture phase. The end of the CO2 capture phase corresponds, in particular, to the point at which the bituminous composition is no longer under CO2 pressure. This release can occur naturally when the bituminous composition is stored at 25°C and under 1013.25 hPa. Such a release phase under these conditions typically lasts at least 10 hours, and in particular 15 to 30 hours. It is also possible that the bituminous composition is subjected to heating during this release phase (Pr), which will accelerate the release of some of the CO2 and thus reduce the duration of the release phase.During such a release phase, generally 50 to 25% by mass of the initially incorporated CO2, and particularly 40 to 30% by mass of the initially incorporated CO2, can be released, leading to a CO2 mass percentage relative to the bitumen base mass that remains at least 0.2 to 3% by mass, preferably 0.2 to 2% by mass, and preferably 0.2 to 0.8% by mass of the bitumen base mass. Indeed, in this case, there is a loss of the trapped CO2, but the initially incorporated mass is greater than when the trapping is carried out at a higher temperature.

[0080] Once the preparation process is complete, or the release phase (Pr) if applicable, the remaining CO2 remains trapped within the bituminous composition under standard storage conditions (25°C and 1013.25 hPa), resulting in a stabilization of the bituminous composition's mass. The mass of the bituminous composition refers to the mass of all its components (particularly the bitumen base, zeolite particles, and any other components present), as well as the CO2 trapped within it when its mass is measured.

[0081] The invention also relates to bituminous compositions that can be obtained by the process described in the context of the invention, and in particular to bituminous compositions, which can be described as stabilized, that can be obtained by the process according to the invention, and at the end of the step of releasing part of the trapped CO2, when the process according to the invention includes one.

[0082] The characteristics described in the preceding sections also apply to the preparation processes according to the invention. Thus, the components involved in the preparation process will preferably be chosen from those previously described and introduced in proportions that lead to the quantities given for the description of the bituminous compositions according to the invention. Use and implementation of bituminous compositions according to the invention

[0083] Various uses for the bituminous compositions obtained according to the invention are envisaged. In particular, the bitumen compositions according to the invention can be used as a bituminous binder. The bituminous binder or bituminous composition according to the invention can, in turn, be used to prepare a mixture with aggregates, particularly road aggregates. With regard to road applications, the invention relates in particular to bituminous mixes as materials for the construction and maintenance of roadbeds and their surfacing, as well as for carrying out all roadworks.

[0084] Bituminous mix refers to a mixture of a bituminous binder with aggregates and optionally mineral and / or synthetic fillers. Bituminous mix comprises a bituminous binder as described in the invention, and optionally mineral and / or synthetic fillers, preferably selected from fines, sand, gravel, and recycled material. The aggregates are mineral and / or synthetic aggregates, including recycled material, with dimensions greater than 2 mm, preferably between 2 mm and 20 mm.

[0085] Also, the invention also relates to a method for preparing a bituminous coating comprising the hot mixing of a bituminous composition according to the invention, with aggregates, and optionally mineral and / or synthetic fillers.

[0086] The bituminous binder according to the invention can advantageously be used to prepare a surface dressing, hot mix asphalt, cold mix asphalt, cold-applied asphalt, or emulsion-treated aggregate. With regard to road applications, the invention also relates to asphalts as materials for manufacturing and surfacing sidewalks.

[0087] Asphalt is defined as a mixture of bituminous binder with mineral and / or synthetic fillers. An asphalt mix comprises a bituminous composition as described in the invention and mineral fillers such as fines, sand, or gravel, and / or synthetic fillers. The mineral fillers consist of fines (particles smaller than 0.063 mm), sand (particles between 0.063 mm and 2 mm), and optionally gravel (particles larger than 2 mm, preferably between 2 mm and 4 mm). Asphalt mixes have 100% compaction and are primarily used for constructing and surfacing sidewalks, whereas asphalt mixes have less than 100% compaction and are used for constructing roads. Unlike asphalt mixes, asphalt mixes are not roller-compacted during placement.

[0088] Also, the invention also relates to a process for preparing an asphalt comprising the hot mixing of a bituminous composition according to the invention, with mineral and / or synthetic fillers.

[0089] Another aspect of the invention relates to the use of a bitumen composition in various industrial applications, particularly for preparing a waterproofing coating, a membrane, or an impregnating layer. Industrial applications of bituminous compositions include the manufacture of waterproofing membranes, noise-reducing membranes, insulation membranes, surface coatings, carpet tiles, and impregnating layers.

[0090] The incorporation of CO2 and zeolite particles does not significantly affect the needle penetration and ring ball temperature of the bituminous compositions, making them suitable for the above applications.

[0091] The invention also relates to a process for preparing an asphalt comprising the hot mixing, at a temperature of 80 to 200 °C, preferably 80 to 180 °C and preferably 100 to 160 °C, of ​​a bituminous composition according to the invention or capable of being obtained according to a process according to the invention, with mineral and / or synthetic fillers.

[0092] The invention also relates to the use of zeolite particles in a bituminous composition in which CO2 is incorporated, to obtain a stabilization of the amount of CO2 remaining trapped within said bituminous composition.

[0093] The characteristics described in connection with the bituminous composition and / or the process for preparing a composition according to the invention apply to the uses, products, and processes described in this section. Furthermore, to achieve stabilization of the amount of CO2 remaining trapped within said bituminous composition, the components and quantities as previously defined, and / or the incorporation and / or storage conditions, will advantageously be applied.

[0094] The examples below, with reference to the attached Figures, illustrate the invention, but are not intended to be limiting. Brief description of the drawings

[0095] [Fig. 1] Figure 1 represents the crystal structure of a FAU zeolite along the

[0111] axis and a cage 0 and the elementary structure D6R which constitute it.

[0096] [Fig. 2] Figure 2 represents the crystal structure of an LTA zeolite along the

[0111] axis and the elementary cages / structures that constitute it.

[0097] [Fig. 3] Figure 3 represents the evolution of the relative % of CO2 remaining in the sample (mass % relative to the mass of CO2 at the outlet of the PAV - from the English "Pressure Ageing Vessel") as a function of the time (h) elapsed at 25 °C after the outlet of the PAV used to carry out the trapping of CO2 (= storage time at 25 °C), for compositions 2 and 4 prepared in the examples and the bitumen base not modified by incorporation of zeolite particles.

[0098] [Fig. 4] Figure 4 represents the evolution of the relative % of CO2 remaining in the sample (mass % relative to the mass of CO2 at the outlet of the PAV) as a function of the time (h) elapsed at 25 °C after the outlet of the PAV used to carry out the trapping of CO2 (= storage time at 25 °C), for compositions 5 to 8 prepared in the examples and the bitumen base not modified by incorporation of zeolite particles.

[0099] [Fig. 5] Figure 5 represents the evolution of the relative % of CO2 remaining in the sample (mass % relative to the mass of CO2 at the outlet of the PAV) as a function of the time elapsed at 25 °C after the outlet of the PAV used to carry out the trapping of CO2(h) (= storage time at 25 °C), for compositions 8 (8- 25°C) and 9 (9-120°C) prepared in the examples ella base bitumen unmodified by incorporation of zeolite particles for which the trapping of CO2 was carried out at 25 °C (bitumen-25°C) or 120 °C (bitumen-120°C).

[0100] [Fig. 6] Figure 6 represents the evolution of the mass % of CO2 remaining in the sample relative to the base mass of bitumen, for the compositions shown in Figure 5. Examples Part 1. Examples of implementation

[0101] Pure bitumen type 35 / 50 according to standard EN 12591 from the Feyzin refinery (bitumen base), produced using a conventional refining process. direct was modified by incorporating different zeolites, then trapping CO2.

[0102] The zeolite particles used are shown in Table 1 below.

[0103] [Table 1]

[0104] The modified bitumen bases were obtained under the following conditions: - Zeolite particles were introduced into the bitumen base already heated to 160°C; - Mixing temperature: 160 °C; - Agitation speed: 200 revolutions / min. (rpm for rotations per minute); - Agitation for 30 minutes or 1 hour. Incorporation of CO2 into modified bitumen bases

[0105] To incorporate CO2 into the bituminous compositions, a PAV device (model used: PAV3 from ATS [Applied Test Systems]) was used. This device is typically used to induce bitumen oxidation, according to standard NF EN 14769. It simulates the long-term oxidative aging of a bitumen composition, representing several years of oxidation on a road. This test is usually carried out at a temperature of 100°C, a pressure of 21 bar (2.1 x 10⁻¹⁰ hPa), and for 20 hours using a compressed air cylinder. The bitumen is introduced into the device in cups, each containing 50 g of the bitumen composition.

[0106] In the context of the invention, where the incorporation of CO2 into a bituminous composition is desired, instead of using a compressed air cylinder as in aging tests, a cylinder of pure CO2 (99%) was used and connected to the PAV device. The bitumen base, incorporating the selected additive, was placed for 20 hours at a temperature of 25°C or 120°C, under a CO2 pressure of 21.1 CP hPa (21 bar), so as to incorporate the CO2 into the bitumen composition. At the end of these 20 hours, the The device was immediately returned to atmospheric pressure and the cups were immediately removed. Measurement of CO2 content in bitumen

[0107] The incorporated CO2 content was measured by weighing, using a precision balance (Sartorius Practum 224-1 S). The cups containing the bitumen were weighed before and after CO2 incorporation by PAV (Pressure Ageing Vessel), as detailed below. The measurements were taken at 25 °C and atmospheric pressure (1013.25 hPa). After PAV in air, there was no difference in mass before and after PAV. After PAV under CO2, the difference in mass obtained therefore corresponds to the mass of CO2 incorporated into the bitumen. Stability study of CO2 trapping

[0108] The stability of CO2 trapping was evaluated at the end of these 20 hours of PAV, maintaining the bituminous composition obtained at ambient temperature (25°C) and under atmospheric pressure (1013.25 hPa). The times mentioned, in particular 5h and 24h, correspond to the time elapsed after the end of the CO2 incorporation stage, and therefore start from the exit of the studied bituminous compositions from the PAV device used for CO2 incorporation. Evaluation of bituminous compositions

[0109] The bituminous compositions were evaluated after 24 hours of storage at 25°C. The following evaluations were carried out by: - the measurement of needle penetration at 25 °C (abbreviation: Pene), according to standard EN 1426, the results being expressed in 1 / 10 mm, - measurement of the ring ball softening temperature (abbreviation: BBT), according to standard EN 1427, with results expressed in °C, - The TBA and the penetrability of composition 8 and pure bitumen, after incorporation of CO2, were measured, before and after aging. First series of tests: use of different zeolites and CO2 trapping at 25°C

[0110] Zeolite particles were introduced at a rate of 3.1% by mass, relative to the mass of the bitumen base. In this case, the mixing time for The incorporation of zeolite particles and the obtaining of the modified bitumen base took 30 minutes.

[0111] Information concerning the zeolites used and the results obtained are presented in Table 2 below and in Figure 3 (for compositions 2 and 4, compared to the unmodified bitumen base by incorporation of zeolite).

[0112] [Table 2]

[0113] It therefore appears that the stabilization of the amount of CO2 occurs more rapidly in the case of LTA 5A zeolite. Thus, further tests were carried out with this zeolite. Second series of tests with LTA 5A zeolite, performing CO2 trapping at 25°C, with different quantities of zeolite and different mixing times

[0114] Zeolite particles were introduced at a rate of 3.1% or 6.4% by mass, relative to the mass of the bitumen base.

[0115] The mixing time used to obtain the modified bitumen base was modulated: 30 minutes or 1 hour.

[0116] Information regarding the preparation conditions and the quantity of CO2 trapped at the outlet of the PAV used to trap CO2 (in mass % per ratio to the mass of the bitumen base) are presented in Table 3 below and the evolution of the relative % of CO2 over time after exiting the PAV used to trap CO2 is presented in Figure 4 (for compositions 2 and 4, compared to the bitumen base not modified by incorporation of zeolite).

[0117] [Table 3]

[0118] * : not modified by incorporation of zeolite particles, but having undergone the same CO2 trapping step.

[0119] The results presented in Figure 4 show that increasing the amount of zeolite introduced increases the amount of CO2 trapped, when the mass of the bituminous composition is stabilized.

[0120] Increasing the mixing time also increases the amount of CO2 trapped and stabilized in the bituminous composition.

[0121] From the refinery to its application, bitumen can be handled and stored at high temperatures, around 160°C. Therefore, hot desorption was also investigated for compositions 7 and 8. For this purpose, after approximately 100 hours of storage at 25°C, following the completion of the CO2 trapping stage (thus stabilizing the mass of the bituminous composition), a sample was placed in a microchamber for 1 hour at 160°C. The amount of CO2 released during the experiment was measured and corresponded to approximately 12% (for composition 8) and 16% (for composition 7) of the mass of CO2 trapped before this heating phase. 3rd series of tests with LTA 5A zeolite, carrying out CO2 trapping at 120°C

[0122] LTA 5A zeolite particles were introduced at a concentration of 6.4% by mass relative to the mass of the bitumen base. The mixing time used to obtain the modified bitumen base was 1 hour.

[0123] The PAV for CO2 trapping was carried out at 120°C and compared to the results obtained with the unmodified bitumen base and those of composition 8, regarding the evolution of the quantity of CO2 trapped, as a function of the storage time at 25°C, after the end of the trapping step (exit from the PAV).

[0124] Table 4 shows the amount of CO2 trapped at the outlet of the PAV used to trap CO2, in % mass, relative to the mass of the bitumen base (% CO2 incorporated).

[0125] [Table 4]

[0126] * : not modified by incorporation of zeolite particles, but having undergone a CO2 trapping step.

[0127] Figures 5 and 6 show the evolution, respectively, of the relative mass percentage of CO2 remaining in the composition (compared to the mass of CO2 trapped at the PAV outlet) and the mass percentage of CO2 trapped, relative to the mass of the bitumen base, as a function of the storage time at 25°C after exiting the PAV (CO2 trapping stage). It is clear from these figures that incorporating CO2 at 120°C immediately stabilizes the trapped CO2, even though the trapped mass resulting from the trapping stage, and therefore also the stabilized mass, is less than in the case of trapping carried out at 25°C. Evaluation of composition 8

[0128] The TBA and penetrability of composition 8 and pure bitumen were measured before and after the incorporation of CO2. Accelerated long-term aging was performed in a pressure aging vessel (PAV) at 100 °C and 21 MPa air pressure. The aging time used was 25 hours.

[0129] The results presented in Tables 5 and 6 show that the presence of zeolite particles and incorporated CO2 do not affect the properties of the bituminous composition obtained.

[0130] [Table 5] Comparative tests

[0132] For comparison, other bituminous compositions modified with an additive other than zeolite particles were subjected to the same CO2 capture step. The results presented were obtained under the following conditions: - The selected additive was introduced into the bitumen base already heated to 160 °C; - Mixing temperature: 160 °C; - Agitation speed: 200 rpm; - Stirring for 30 minutes; - The quantity of additive was 3.0% w / w relative to the total mass of the modified bitumen base obtained, corresponding to 3.1% w / w relative to the mass of the bitumen base.

[0133] The results obtained for the bituminous compositions after storage for 5 or 24 hours following the CO2 trapping step under a vapor barrier at 25°C are presented in Table 7. They show that with the other additives, the amount of CO2 trapped is far from stabilizing after 24 hours, unlike what is obtained with the zeolite particles in the context of the invention. Indeed, in the case of zeolite particles, after 24 hours of storage, at least 60 to 80% of the CO2 trapped at 5 hours is still trapped, which demonstrates the stabilization of the CO2, whereas in the other cases, after 24 hours of storage, less than 60% of the CO2 trapped at 5 hours is still trapped.

[0134] [Table 7]

[0135] (a)amine (PIBA03)

Claims

Demands

1. Bituminous composition comprising a bitumen base and zeolite particles, wherein the bitumen base represents at least 75% by mass of the total mass of the bitumen composition, characterized in that CO2 is trapped in said bitumen composition and represents 0.2 to 3% by mass of the mass of the bitumen base and the zeolite particles represent 0.1 to 10% by mass of the mass of the bitumen base.

2. Bituminous composition according to claim 1, characterized in that the CO2 trapped in said bituminous composition represents from 0.2 to 2% by mass, and preferably from 0.2 to 0.8% by mass, of the mass of the bitumen base and the zeolite particles represent from 1 to 8% by mass, and preferably from 3 to 7% by mass, of the mass of the bitumen base.

3. Bituminous composition according to claim 1 or 2, characterized in that the zeolite particles are particles of a zeolite selected from faujasites, in particular CBV 400, CBV 760 and 13X, and LTA, preferably the zeolite is an LTA 5A.

4. Bituminous composition according to any one of the preceding claims, characterized in that the zeolite particles incorporated in the bituminous composition have a specific surface area determined according to the BET method of 20 to 600 g / m² 2 , preferably 50 to 400 g / m 2 .

5. Bituminous composition according to any one of the preceding claims, characterized in that the mass of the bituminous composition is stable at 25°C and under 1013.25 hPa, over a period Ps of at least 5 hours, preferably of at least 10 hours, and advantageously of at least 25 hours.

6. Bituminous composition according to any one of the preceding claims, characterized in that the bitumen base represents at least 80% by mass and preferably at least 85% by mass of the total mass of the bituminous composition.

7. Bituminous composition according to any one of the preceding claims, characterized in that it further comprises one or more polymers selected from olefinic polymers and elastomers, in particular from olefinic polymers and crosslinked or crosslinkable elastomers, preferably representing from 0.5 to 12% by mass, preferably from 0.3 to 10% by mass, and even more preferably from 0.5 to 7% by mass, of the mass of the bitumen base.

8. A process for preparing a bituminous composition, wherein the bitumen base represents at least 75% by mass of the total mass of the bitumen composition, comprising the following successive steps: a) obtaining a modified bitumen base, comprising the incorporation of zeolite particles into a bitumen base, with the zeolite particles representing from 0.1 to 10% by mass, said incorporation being followed or accompanied by mixing, preferably under heating to a temperature in the range of 90 to 230 °C, preferably in the range of 120 to 200 °C, and preferably in the range of 120 to 180 °C; b) trapping CO2 in the modified bitumen base at a mass content representing from 0.2 to 6% by mass, preferably from 0.2 to 4% by mass, and preferably from 0.2 to 2% by mass, and more preferably from 0.2 to 1.5% by mass, of the mass of the bitumen base.

9. A preparation method according to claim 8, characterized in that at step a), the mass of zeolite particles incorporated represents 1 to 8% by mass, and preferably 3 to 7% by mass, of the base bitumen mass.

10. A preparation method according to claim 8 or 9, characterized in that during step a), one or more polymers selected from olefinic polymers and elastomers, in particular from crosslinkable elastomers, is / are also incorporated into the bitumen base, said polymer(s) preferably being introduced at a rate of 0.1 to 12% by mass, preferably 0.3 to 10%, and preferably 0.5 to 7% by mass, of the mass of the bitumen base.

1. A preparation method according to any one of claims 8 to 10, characterized in that the CO2 trapping is carried out by placing the modified bitumen base in a chamber under CO2 pressure, the chamber being maintained at a temperature ranging from 10 to 200 °C, preferably from 20 to 160 °C, and preferably from 25 to 160 °C, or even from 80 to 160 °C, the CO2 pressure being notably chosen in the range of 5.10 3 at 8.10 4 hPa, preferably in the range of 5.10 3 at 5.10 4 hPa, and preferably in the range of 1.10 4 at 3.10 4 hPa.

12. A preparation method according to any one of claims 8 to 11, characterized in that it comprises a release step which results in a quantity of CO2 trapped in the bituminous composition representing 0.2 to 3% by mass, preferably 0.2 to 2% by mass, and preferably 0.2 to 0.8% by mass, of the mass of the bitumen base.

13. Use of a bituminous composition according to any one of claims 1 to 7, for preparing a waterproofing coating, a membrane, or an impregnating layer.

14. Use of a bituminous composition according to any one of claims 1 to 7, for preparing a surface dressing, hot mix asphalt, cold mix asphalt, cold poured asphalt, emulsion aggregate or wearing course, said bituminous composition being associated with recycled aggregates and / or milled material.

15. Use of zeolite particles in a bituminous composition in which CO2 is incorporated and which comprises a bitumen base representing at least 75% by mass of the total mass of the bitumen composition, said zeolite particles representing from 0.1 to 10% by mass, preferably from 1 to 8% by mass, and preferably from 3 to 7% by mass, of the mass of the bitumen base, to achieve stabilization of the amount of CO2 remaining trapped within said bitumen composition.

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