Ettringite

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Ettringite

• 3CaO.Al2O3.3CaSO4.32H2O.

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Ettringite in natureEttringite is naturally
polluted by Si, Fe, K, Na, Co. It is very
difficult to find it in bigger amount
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Structural chemical formulaIs compounded from
columns and channels
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(No Transcript)
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Preparation and formation of ettringite

• 6Ca(OH)2 Al2(SO4)3. 18H2O H2OgtCa6Al2(SO4)3(OH
  )12. 26H2O
• Al2(SO4)3 CaCl2 12NaOH 26 H2O
  Ca6(Al2O6)(SO4)3. 32 H2O 12NaCl
• 3CaCO3 Al2(SO4)3 gt Ca3Al2O3(SO4)3 3CO2
• Ca3Al2O3(SO4)3 3CaO gt Ca6(Al2O6)(SO4)3. 32
  H2O
• CA 2CH 3CS.2H 24H gt C3A. 3CS.H32
• 3CA 5CH 6CS.2H 26H gt C3A. 3CS.H32
• CA2 5CH 6CS.2H 47H gt 2C3A. 3CS.H32
• C12A7 9CH 21CS.2H 173H gt7C3A. 3CS.H32
• CA6 17CH 18CS.2H 139Hgt 6C3A. 3CS.H32
• C CaO, A Al2O3, S SO3, H - H2O

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usage and characteristics of ettringite

• fixation outlet ions
• belated formation DEF expansion at concrete
• production of papers, light gypsumwallboard
  boards, ettringite grains which have improved
  fireproof qualities
• possible substituent of cations and anions
• ( heavy metals, or radioactive materials )

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DEF ettringite

• Porous materials, including stone, mortar, and
  concrete,
• can be damaged when crystals precipitate from
  the liquid
• in their pores. Salts may be inherent to the
  material (as is the case in cementitious
  materials), or be absorbed withground water or
  formed by reaction with atmospheric
• pollutants (particularly sulfates), or
  created by the metabolic activity of microbes.

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DEF ettringite after 30 days
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Analysis of ettringite by SEM or RTX
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ettringite below electron microscope
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vocabulary

• pruhlednost transparency
• tvrdost hardness
• tepnost fissionability
• lesk lustre
• nezárivost rayless
• sádrokartonové gypsumwallboard
• odpadních outlet
• vlákno grains

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