[No public or meaningful name is available]

Nanomaterial crystalline phase

Administrative data

Endpoint:

nanomaterial crystalline phase

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Qualifier:

no guideline followed

GLP compliance:

no

Type of method:

x-ray diffraction (XRD)

Test material

Test material information

Constituent 1

Reference substance name:

Amorphous hydrothermal synthesis product of water, calcium oxide and quartz

Molecular formula:

Not applicable for UVCB substance

IUPAC Name:

Amorphous hydrothermal synthesis product of water, calcium oxide and quartz

Test material form:

solid: nanoform

Data gathering

Instruments:

To determine crystallinity XRD analysis and TEM analysis with SAD was performed on the test item.

Results and discussion

Crystalline phase

Crystalline phase 1

Key result

Common name:

silicon dioxide (Quartz)

Crystalline phase 2

Key result

Common name:

calcium hydroxide (Portlandite)

Crystalline phase 3

Key result

Common name:

calcium carbonate (Calcite)

Crystalline phase 4

Key result

Common name:

Xonotlite (a mineral of the calcium silicate hydrate mineral group)

Crystallographic composition:

The XRD analysis on the liquid suspension shows different mineral phases present in the suspension: calcium carbonate (Calcite), calcium hydroxide (Portlandite), silicon dioxide (Quartz), and a mineral phase similar to Xonotlite. Xonotlite is a mineral of the Calcium Silicate Hydrate mineral group. The major basal reflections (0,0,1) and (0,0,2) are weakly present but are visible. All other peaks are present with increased full width half maximum (FWHM) correlating with the crystallite size of Xonotlite. Derived from the FWHM the crystallite size is in the range 50 to 100 nm.

The nanoform of the substance can be described as multiconstituent nanoform dominated by a crystalline CSH phase with low crystallite size (~ 15 nm). The other constituents in the inorganic composition represented by crystalline phases Portlandite, Calcite, and Quartz. Additionally, an X-ray amorphous phase is present, which shows tobermorite like short range order derived from TEM with SAD.

Applicant's summary and conclusion

Conclusions:

The XRD analysis on the liquid suspension shows different mineral phases present in the suspension: calcium carbonate (Calcite), calcium hydroxide (Portlandite), silicon dioxide (Quartz), and a mineral phase similar to Xonotlite.