Process for preparing a composite material from an organic liquid and resulting material

Abstract

The present invention relates to a method for preparing a composite material from an organic liquid, consisting of preparing a geopolymer by dissolution/polycondensation of an aluminosilicate source in an activation solution comprising said organic liquid. The present invention also relates to the thereby prepared composite material.

Claims

1. A method for preparing a composite material from an organic liquid, comprising: preparing a geopolymer by dissolution/polycondensation of at least one aluminosilicate source in an activation solution including said organic liquid, said organic liquid representing 20% to 70% by volume based on a total volume of said composite material, said organic liquid including at most 50% by mass of triglycerides based on a total dry mass of said organic liquid, and wherein said preparing the geopolymer includes a) preparing the activation solution including said organic liquid and at least one surfactant, said surfactant being present in a proportion of 1% to 10% based on a total volume of the activation solution, b) adding the at least one aluminosilicate source to the activation solution in step (a) to obtain a mixture, and c) subjecting the mixture in step (b) to conditions allowing hardening of the geopolymer, wherein said composite material is a geopolymeric matrix in which at least one of microbeads and nanobeads of said organic fluid are trapped or coated, and wherein said organic liquid comprises at least one compound selected from the group consisting of a commercial scintillator liquid, benzene, toluene, xylene, ethylbenzene, kerosene, hexane, cyclohexane, octane, ethylcyclohexane, dodecane, eicosane, phenol, dichloromethane, trichloroethane, dichlorobenzene, trichloroethylene, 2-octane, 4-dodecanone, tributyl phosphate (TBP), tetrahydrofurane (THF), and diethyl ether.

2. The method according to claim 1, wherein said organic liquid is in a supported form.

3. The method according to claim 2, wherein said supported form is earth, sand, clay, rubble, granulate, gravel, or one of their mixtures.

4. The method according to claim 1, wherein said organic liquid comprises at least one of a heavy metal, a trace element, or a radioelement.

5. The method according to claim 1, wherein said activation solution contains at least one silicate component selected from the group consisting of silica, colloidal silica, and glassy silica.

6. The method according to claim 1, wherein the activation solution/MK mass ratio with an activation solution term representing the mass of activation solution containing the organic liquid (expressed in g) and MK representing the aluminosilicate source mass (expressed in g) used is between 0.6 and 2.

7. The method according to claim 1, wherein the activation solution/MK mass ratio with an activation solution term representing the mass of activation solution containing the organic liquid (expressed in g) and MK representing the aluminosilicate source mass (expressed in g) used is between 1 and 1.5.

8. The method according to claim 6, wherein the activation solution/MK mass ratio with the activation solution term representing the mass of activation solution containing the organic liquid and a surfactant (expressed in g) and MK representing the aluminosilicate source mass (expressed in g) used is between 1 and 1.5.

9. The method according to claim 1, wherein, in addition to the at least one aluminosilicate source, sand, granulate, and/or fines are added to the activation solution during said step (b).

10. The method according to claim 1, wherein the conditions allowing hardening during said step (c) comprise a curing step.

11. The method according to claim 10, wherein the curing step is followed by a drying step.

12. A method for treatment and/or inertization of an organic liquid, comprising: preparing the composite material from said organic liquid according to the method as defined in claim 1.

Description

SHORT DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a view of an activation solution with 30% by mass of oil.

(2) FIG. 2 is a view of the kneading of the activation solution with the oil after adding metakaolin.

(3) FIG. 3 is a view of geopolymer specimens containing 20% by volume of oil.

(4) FIG. 4 is a view of a specimen 4416 cm.sup.3 of geopolymer containing 20% by volume of scintillator liquid.

DETAILED DISCUSSION OF PARTICULAR EMBODIMENTS

(5) A geopolymeric mortar was prepared with 20% by volume of oil.

I. Raw Materials

(6) The products used for the geopolymer are metakaolin from Pieri Premix MK (Grade Construction Products), NaOH (Prolabo, 98%), SiO.sub.2 (Tixosil, Rhodia), siliceous sand (Sibelco) and motor oil as an organic waste.

(7) The composition is given in the table 1 below.

(8) TABLE-US-00001 TABLE 1 Composition of the mortar for micro-encapsulation of oil Activation solution/ Binding composition (in g) metakaolin mass Geopolymeric SiO.sub.2: 223 1.28 mortar with oil NaOH: 242 Metakaolin: 882 Sand: 821 Oil: 321

II. Operation Procedure

(9) II.1. Preparation of the Activation Solution

(10) The steps of this preparation are the following: Preparation of a concentrated soda solution (10 M), Addition of Tixosil silica with stirring in order to obtain an activation solution, Addition of oil to the activation solution, Sustained stirring at 300 rpm for a minimum of 10 hours in order to obtain a uniform solution, Transfer of the mixture into a kneader with a view to geopolymerization (FIG. 1).

(11) II.2. Geopolymerization

(12) The metakaolin+sand mixture is added to the activation solution (FIG. 2).

(13) The geopolymeric mortar containing the oil is poured into molds in order to obtain measurement specimens (FIG. 3). The hermetic molds are kept in an oven with a controlled atmosphere (20 C. at atmospheric pressure) during the whole of the curing which lasts for at least three days.

III. Obtained Material and its Properties

(14) Obtaining a monolithic geopolymer block with oil is clearly visible in FIG. 3.

(15) These specimens were therefore characterized by mechanical strength tests after storage in air, in a bag and sealed, in the form of two independent tests (test 1 and test 2). The results are shown in Table 2. The geopolymer has good mechanical properties (>8 MPa compatible with the ANDRA requirements) and integrity of the materials after 28 days of preservation is demonstrated.

(16) TABLE-US-00002 TABLE 2 Mechanical properties at 28 days of the geopolymers containing 20% by volume of oil Storage Storage Storage in air in bag under water Flexure (MPa) Test 1 2.235 3.095 2.612 Test 2 3.574 2.998 2.509 Compression (MPa) Test 1 25.69 23.81 22.63 Test 2 29.00 23.06 23.44

IV. Other Example According to the Invention

(17) A geopolymer paste was prepared with 20% by volume of scintillator liquid Ultima gold XR from Perkin Elmer.

(18) The composition and the mechanical properties are given in Table 3.

(19) TABLE-US-00003 TABLE 3 Composition of the mortar for micro- encapsulation of scintillator liquid Binding Mechanical composition properties at 28 (in g) Water/metakaolin days in air Geopolymer paste SiO.sub.2: 21.6 0.77 30 MPa in with scintillator NaOH: 24 compression liquid Metakaolin: 79.7 5.4 MPa in Scintillator flexure liquid: 22

(20) The operating procedure for preparing the geopolymer paste with the scintillator liquid is identical with the one shown earlier with oil.

(21) The geopolymer mortar containing the scintillator liquid is poured into molds in order to obtain measurement specimens (FIG. 4).

REFERENCES

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