SYNTHESIS AND CRYSTAL STRUCTURE OF HYDRATED CALCIUM SILICATES IN THE CaO - SiO_2 - H_2O SYSTEM

CaO-SiO_2-H_2O体系水合硅酸钙的合成及晶体结构

• 批准号: 62470050
• 负责人: MITSUDA Takeshi
• 金额: $ 3.58万
• 依托单位: NAGOYA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-62470050/
• 关键词: CALCIUM SILICATE; SYNTHESIS; NMR; TOBERMORITE; HILLEBRANDITE; DICALCIUM SILICATE; 電子顕微鏡; CーSーH; 含水カルシウム珪酸塩; 構造; 分析電子顕微鏡; 水和物

beta C_2S was prepared at 600゜-1000゜C from hillebrandite, Ca^-_(SiO_3)(OH)_2, which was hydrothermally made using quartz below 10 m and CaO eith Ca/Si=2.0 at 250゜C for 20 h in stirring suspensions under saturated steam pressure. Hillebrandite shows fibrous or lath-like crystals lying on (001) elongated to b with a=16.588(2) , b=7.2670(8) , c=11.787(1) , beta=90.231(7)゜, specific surface area of 10.1 m^2g (BET), crystallite size of 483 , and single chains (MASNMR). On heating hillebrandite was decomposed into beta-C2S at 600゜C and further transformed into alpha'L phase at 650゜-900゜C, alpha'H phase at 1170゜C, and alpha phase at 1430゜C. Samples heated below 1430゜C were stabilized into beta form by cooling to room temperature. The crystals of beta-C_2S obtained by heat treatment at 600゜-1000゜C retained the same morphology and crystallographic orientations of hillebrandite, and gave the following crystallite size and specific surface area: 289 - 6.3 m^2/g (600゜C), 360 - 5.2m^2/g (800゜C), 721 - 2.5m^2/g (1000゜C).The results of calorimetry showed the faster the rate of beta-C<@D22@>D2S hydration, the lower the treatment temperature of hillebrandite. Within 2 weeks at w:s = 1.0 and 20゜C, perfectly hydrated products of C-S-H with Ca(OH)<@D22@>D2 were obtained from the beta-C<@D22@>D2S prepared at 600゜C. Analytical electron microscopy of the C-S-H in the beta-C<@D22@>D2S pastes cured for 28 days gave a mean Ca/Si ratio which vary greatly with w:s ratio; 1.97 (w:s = 1.0), 1.86 (2.0), 1.70 (5.0) and 1.51 (20). MASNMR spectroscopy of the C-S-H showed a strong Q<@D11@>D1 and a weak Q<@D12@>D2 in the absence of Q<@D10@>D1, Q<@D13@>D1 and Q<@D14@>D1. This suggests that the silicate anions of the C-S-H in beta-C<@D22@>D2S pastes are mixtures of dimer and short single chain.

在600 ℃-1000 ℃下，以10 μ m以下的石英和Ca/Si=2.0的CaO为原料，在250 ℃下搅拌20 h，在饱和蒸汽压下水热合成了钙铝榴石Ca^-_（SiO_3）（OH）_2，制备了β C_2S。钙铝榴石为纤维状或板条状晶体，位于（001）面，拉长至B，a=16.588（2），B=7.2670（8），c=11.787（1），β =90.231（7）μ m，比表面积为10.1 m^2 g（BET），晶粒尺寸为483，且为单链（MASNMR）。加热时，在600 ℃时，hillebrandite分解为β-C2 S，在650 ℃-900 ℃时进一步转化为α 'L相，在1170 ℃时转化为α' H相，在1430 ℃时转化为α相。加热至1430 ℃以下的样品通过冷却至室温稳定为β形式。在600 ℃ ~ 1000 ℃热处理得到的β-C_2S晶体保持了与hillebrandite相同的形貌和晶体学取向，其晶粒尺寸和比表面积如下：289 - 6.3 m^2/g（600 ℃），360 - 5.2m^2/g（800 ℃），721 - 2.5m^2/g（1000 ℃）。量热分析结果表明，β-C <@D22@> D2 S水化速率越快，水化温度越低。在w：s = 1.0和20 ℃下2周内，由在600 ℃下制备的β-C <@D22 @> D2 S得到C-S-H与Ca（OH）<@D22 @> D2的完全水合产物。在固化28天的β-C <@D22@> D2 S糊剂中的C-S-H的分析电子显微镜检查给出了随w：s比变化很大的平均Ca/Si比; 1.97（w：s = 1.0）、1.86（2.0）、1.70（5.0）和1.51（20）。C-S-H的MASNMR谱显示在不存在Q<@D10@>D1、Q<@D13@>D1和Q<@D14@>D1的情况下，强Q<@D11@> D1和弱Q<@D12@>D2。这表明β-C <@D22@> D2 S浆料中C-S-H的硅酸根阴离子是二聚体和短单链的混合物。

项目成果

光田武: J.Am.Ceramic Soc.

光田武：J.Am.Ceramic Soc。

光田武: セメント技術年報. 41. 9-17 (1987)

Takeshi Mitsuda：水泥技术年度报告。41. 9-17 (1987)。

光田武: J.Am. Ceramic Soc.

光田武：J.Am.陶瓷学会。

光田武: セラミックス. 23. 748-752 (1988)

光田武：陶瓷 23. 748-752 (1988)

光田武: Advanced Characterization Techniques for Ceramics.1988.1988. 1-8 (1989)

Takeshi Mitsuda：陶瓷高级表征技术。1988.1988 1-8 (1989)。