# US 2017/0253530 A1 · White carbonatable calcium silicate-based cements and methods of preparation and use thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0253530 A1 - Document ID: US20170253530A1 - Status: Published application - Kind: A1 - Application number: 15/449,736 - Filed: 2017-03-03 - Published: 2017-09-07 - Earliest claimed: 2016-03-04 - Assignees: Solidia Technologies, Inc. - Applicants: Solidia Technologies, Inc. - Inventors: Sadananda Sahu; Sean Quinn; Anuj Seth; Jayson Bryant; Deepak Ravikumar - Web page: https://patentgrep.com/patent/US20170253530A1 ## CPC - C04B 7/345: Hydraulic cements not provided for in one of the groups C04B7/02 - C04B7/34 - C04B 28/188: {the Ca-silicates being present in the starting mixture} - C04B 2111/00019: {Carbon dioxide sequestration} - C04B 2111/802: {White cement} - Y02P 40/18: Carbon capture and storage [CCS] - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract The invention provides a new class of carbonatable calcium silicate-based, white clinkers and the ground cement produced from these clinkers, as well as methods of their production and use thereof. The disclosed white clinkers and the ground cement exhibit a high brightness and are suitable for use in products with high aesthetic considerations. ## Claims ### Claim 1 A white carbonatable calcium silicate cement composition, comprising: one or more discrete calcium silicate phases selected from CS (wollastonite or pseudowollastonite), C3S2 (rankinite), C2S (belite, larnite, bredigite), and an amorphous calcium silicate phase, wherein the one or more discrete calcium silicate phases form about 30% or more by mass of the total phases, and wherein elemental Ca and elemental Si are present in the composition at a molar ratio from about 0.8 to about 1.2; and metal oxides of Al, Fe and Mg are present at about 30% or less by mass, wherein the total color-imparting oxides of one or more of metals selected from Fe, Ti, Mn and Cr are present about 2.5% or less by mass of the total cement composition, wherein the cement composition is characterized by a reflectance value (L*) of greater than about 85%. ### Claim 2 (depends on 1) The composition of claim 1, wherein the cement composition is suitable for carbonation with CO2 at a temperature of about 30° C. to about 90° C. to form a composite material comprising a binder matrix with a mass gain of about 10% or more. ### Claim 3 (depends on 1) The composition of claim 1, comprising one or more residual SiO2 and CaO phases. ### Claim 4 (depends on 1) The composition of claim 1, comprising one or more melilite phases having the general formula (Ca,Na,K)2[(Mg, Fe2+,Fe3+,Al,Si)3O7]. ### Claim 5 (depends on 1) The composition of claim 1, wherein the composition comprises one or more calcium silicate phases existing in an amorphous state and one or more calcium silicate phases existing in a crystalline state. ### Claim 6 (depends on 1) The composition of claim 1, wherein the composition comprises calcium silicate phases existing only in an amorphous state. ### Claim 7 (depends on 1) The composition of claim 1, wherein the composition comprises calcium silicate phases existing in both the crystalline state and the amorphous state. ### Claim 8 (depends on 1) The composition of claim 1, wherein the composition is a powder having a reflectance value (L*) of greater than about 85%. ### Claim 9 (depends on 8) The composition of claim 8, wherein the composition is a powder having a reflectance value (L*) of greater than about 90%. ### Claim 10 (depends on 9) The composition of claim 9, wherein the composition is a powder having a reflectance value (L*) of greater than about 95%. ### Claim 11 (depends on 1) The composition of claim 1, wherein the metal oxides of one or more metal selected from Fe, Ti, Mn and Cr are incorporated into a melilite phase. ### Claim 12 (depends on 11) The composition of claim 11, wherein the metal oxides of one or more metal selected from Fe, Ti, Mn and Cr are incorporated into an amorphous phase. ### Claim 13 (depends on 11) The composition of claim 11, wherein the metal oxides of one or more metal selected from Fe, Ti, Mn and Cr are incorporated into a melilite phase and an amorphous phase. ### Claim 14 (depends on 4) The composition of claim 4, wherein the one or more melilite phases are characterized by a refractive index between about 1.5 and about 1.8. ### Claim 15 (depends on 1) A composite material formed by carbonation of a cement composition according to claim 1. ### Claim 16 A method for producing a white carbonatable calcium silicate cement, comprising: providing a raw material set comprising CaO and SiO2; grinding the raw material set to obtain a precursor mixture, wherein the molar ratio of CaO to SiO2 is from about 0.8 to about 1.2, wherein the precursor mixture comprises: (i) less than about 21.2% by mass the oxides of Al, Fe and Mg, and (ii) less than about 1.5% by mass metal oxides of one or more metals selected from Fe, Ti, Mn and Cr; firing the precursor mixture to a temperature in the range from about 800° C. to about 1,400° C. to obtain a white carbonatable calcium silicate clinker; and grinding the white carbonatable calcium silicate clinker to a fineness of about 200 to about 800 m2/kg to produce the white carbonatable calcium silicate cement having a reflectance value (L*) of greater than about 85%. ### Claim 17 (depends on 16) The method of claim 16, wherein the precursor mixture is prepared from a raw material set selected from limestone, sand, silts, sandstones, silica-rich clays, diatomaceous earths, marl, fly ash, and silica fume. ### Claim 18 (depends on 17) The method of claim 17, wherein the raw material set is selected to achieve a precursor mixture with less than about 1.5% by mass of transition metal oxides. ### Claim 19 (depends on 17) The method of claim 17, wherein the raw material set is selected to achieve a precursor mixture with less than about 1.5% by mass of metal oxides of one or more metal selected from Fe, Ti, Mn and Cr. ### Claim 20 The method of 16, wherein firing the precursor mixture is performed at a temperature between about 1,300° C. to about 1,400° C. ### Claim 21 The method of 16, wherein after firing the white carbonatable calcium silicate clinker is subjected to cooling by forced air in the range of about 1,400° C. to about 500° C. under an uncontrolled atmosphere. ### Claim 22 The method of 16, wherein after firing the white carbonatable calcium silicate clinker is subjected to cooling by forced air in the range of about 1,400° C. to about 500° C. under a reducing atmosphere. ### Claim 23 The method of 16, wherein after firing the white carbonatable calcium silicate clinker is subjected to a cooling in the range of about 1,400° C. to about 500° C. by quenching in water. ### Claim 24 The method of 16, wherein grinding the raw material set to obtain a precursor mixture is performed in a grinder with a steel grinding surface. ### Claim 25 The method of 16, wherein grinding the white carbonatable calcium silicate clinker achieves a fineness of about 200 m2/kg to about 400 m2/kg to produce the white carbonatable calcium silicate cement. ### Claim 26 The method of 16, wherein grinding the white carbonatable calcium silicate clinker achieves a fineness of about 400 m2/kg to about 800 m2/kg to produce the white carbonatable calcium silicate cement. ### Claim 27 The method of 26, wherein grinding the white carbonatable calcium silicate clinker achieves a fineness of about 400 m2/kg to about 600 m2/kg to produce the white carbonatable calcium silicate cement.