Experimental leaching of natural cement from Maqarin (Jordan): study and modeling of the alteration processes

摘要

A leaching experiment was undertaken on a natural cement from Maqarin (Jordan). The leaching protocol, constant pH, renewed solution under a CO_2 free atmosphere, was identical to that used for industrial cements. Chemical analyses of solid and solution and mineralogical investigations are presented and interpreted. A modeling of this complex heterogeneous system based on simple assumptions is performed and compared to observations. The link between field and experimental observations seems to be related to the rate limited precipitation of secondary portlandite and CSH phases upon larnite alteration.