Hydraulic binder with low carbon footprint and high early strength

1 . A binder composition comprising:

a Portland cement and/or a ground Portland cement clinker;

a calcium aluminate cement (CAC) or a mixture of the calcium aluminate cement (CAC) and a calcium sulfo aluminate cement (CSA);

and

a pozzolanic and/or latent hydraulic material,

wherein the binder composition comprises at least 1.5% of calcium sulfate to a total amount of the binder composition by weight, and

wherein the calcium aluminate cement (CAC) comprises between 50% and 98% of an amorphous phase by weight.

2 . The binder composition according to claim 1 , further comprising a calcium sulfate source, wherein the binder composition comprises:

(a) 20% to 90% by weight of the Portland cement (PC) and/or the ground Portland cement clinker;

(b) 0.5% to 40% by weight of the calcium aluminate cement (CAC) or the mixture of the calcium aluminate cement (CAC) and the calcium sulfo aluminate cement (CSA);

(c) 1.5% to 44.5% by weight of the calcium sulfate source; and

(d) 5 to 50% by weight of the pozzolanic material,

such that a total amount of said (a), (b), (c), and (d) in the binder composition equals 100% relative to a total amount of the binder composition.

3 . The binder composition according to claim 1 , further comprising a calcium sulfate source, wherein the binder composition comprises:

(e) 20% to 70% by weight of the Portland cement (PC) and/or the ground Portland cement clinker;

(f) 2% to 20% by weight of the calcium aluminate cement (CAC) or the mixture of the calcium aluminate cement (CAC) and the calcium sulfo aluminate cement (CSA);

(g) 2% to 15% by weight of the calcium sulfate source; and

(h) 10% to 70% by weight of the pozzolanic and/or latent hydraulic material,

such that a total amount of said (e), (f), (g), and (h) in the binder composition equals 100% relative to a total amount of the binder composition.

4 . The binder composition according to claim 1 , wherein the pozzolanic material is a calcined clay.

5 . The binder composition according to claim 1 , further comprising a calcium sulfate source, wherein the binder composition comprises:

(i) 0.5% to 70% by weight of the Portland cement;

(j) 0.5% to 20% by weight of the calcium aluminate cement (CAC);

(k) 0.5% to 15% by weight of the calcium sulfate source; and

(l) 20% to 95% by weight of the latent hydraulic material,

such that a total amount of said (i), (j), (k), and (l) in the binder composition equals 100% relative to a total amount of the binder composition.

6 . The binder composition according to claim 1 , further comprising a calcium sulfate source, wherein the binder composition comprises:

(m) 0.5% to 50% by weight of the Portland cement;

(n) 0.5% to 20% by weight of the calcium aluminate cement (CAC);

(o) 0.5% to 15% by weight of the calcium sulfate source; and

(p) 40% to 95% by weight of the latent hydraulic material,

such that a total amount of said (m), (n), (o), and (p) in the binder composition equals 100% relative to a total amount of the binder composition.

7 . The binder composition according to claim 1 , wherein the latent hydraulic material is ground granulated blast-furnace slag.

8 . The binder composition according to claim 1 , further comprising 5% to 40% by weight of carbonaceous mineral.

9 . The binder composition according to claim 1 , further comprising one or more set modifiers.

10 . The binder composition according to claim 9 , wherein the modifier is selected from the group consisting of citric acid, tartaric acid, sodium gluconate, Na 2 CO 3 , and K 2 CO 3 .

11 . The binder composition according to claim 1 , wherein the calcium aluminate cement comprises from 30% to 75% of Al 2 O 3 and from 0.1% to 18% of Fe 2 O 3 by weight.

12 . The binder composition according to claim 1 , wherein the pozzolanic material comprises between 1% and 99% by weight of metakaolin (MK).

13 . The binder composition according to claim 1 which additionally comprises an added calcium sulfate source.

14 . The binder composition according to claim 13 , wherein the added calcium source is gypsum, anhydrite, hemihydrate, or a mixture thereof.

15 . The binder composition according to claim 1 , further comprising a calcium sulfate source, wherein the binder composition comprises:

(q) 0.5% to 60% by weight of the Portland cement;

(r) 0.5% to 20% by weight of the calcium aluminate cement (CAC);

(s) 0.5% to 15% by weight of the calcium sulfate source; and

(t) 20% to 95% by weight of the latent hydraulic material,

such that a total amount of said (q), (r), (s), and (t) in the binder composition equals 100% relative to a total amount of the binder composition.

16 . A process of preparation of a construction composition comprising mixing the binder composition according to claim 1 with water.

17 . A construction composition obtained by the process according to claim 16 .

18 . The construction composition according to claim 17 , wherein the construction composition is a mortar composition or a concrete composition.

19 . A construction part comprising the construction composition of claim 17 .