Continuous monitoring for leaching of calcium sulfoaluminate cement pastes incorporated with ZnCl2 under the attacks of chloride and sulfate.
Chemosphere
; 223: 91-98, 2019 May.
Article
en En
| MEDLINE
| ID: mdl-30771652
ABSTRACT
Ionic zinc is considered as an environmental pollutant. This work systematically investigated leaching mechanisms of calcium sulfoaluminate cement (CSA) pastes incorporated with/without ZnCl2 under the attacks of chloride and/or sulfate. The leaching behaviors of CSA pastes in the leaching solution are in-situ and continuously monitored by innovative non-contact electrical impedance measurement (NCEIM) and pH meter. The dissolution and diffusion during the leaching process are experimentally identified. Other techniques are also performed to verify the finding of NCEIM the ion chromatograph and inductively coupled plasma optical emission spectrometer reveal the leaching or decomposition sequence of CSA pastes during the leaching process. Besides, results from XRD and SEM techniques demonstrate that main solid products in CSA pastes are ettringite and calcium monosulfoaluminate hydrates. The incorporation of Zn in the pastes has great impact on the decomposition of CSA pastes in the temperature elevation. External chloride and/or sulfate attacks significantly alter the pore structure of CSA pastes during the leaching process.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
2_ODS3
Problema de salud:
2_quimicos_contaminacion
Asunto principal:
Compuestos de Azufre
/
Contaminación del Agua
/
Cloruros
/
Compuestos de Zinc
/
Compuestos de Calcio
/
Compuestos de Aluminio
/
Materiales de Construcción
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Chemosphere
Año:
2019
Tipo del documento:
Article
País de afiliación:
China