The MECAGEOPOLY Project was aimed at proving that: a) the mechano-chemical activation of kaolins is a valid alternative to the thermal treatment at 650-750°C for the industrial production of PSS geopolymeric binders to be used in building construction and in other industrial applications; b) geopolymeric binders obtained by mechano-chemical activation of kaolins have similar properties than those obtained by thermal treatments; c) the mechano-chemical treatment can be exploited for making geopolymeric binders from other alumino-silicate rocks, such as quarry wastes of volcanic tuff cemented by glass (welded tuffs) or by authigenic minerals (zeolites), that are difficult or impossible to activate by thermal processes; d) the mechano-chemical process is easier to control than the thermal process and it is feasible at an industrial scale; e) the mechano-chemical treatment simplifies the industrial production of PSS geoplymeric binders by combining in a single step the grinding and thermal treatment of the raw material. These objectives were expected to be met in a time period of 2 years, after an evaluation of the results obtained in the first year of activity, aimed at demonstrating the suitability of the mechano-chemical processing to get metakaolins (MKA's) from a commercial kaolin (BS-4) sufficiently reactive for the synthesis of KPSS geopolymers. Although the main objectives of the first year were reached, the reactivity of mechanically activated MKA from BS-4 was higher than that of MKA from BS-4 obtained by thermal treatment. This produced more porous KPSS geopolymers, that showed slightly better thermal properties than KPSS obtained from MKA obtained by thermal treatment, but werecharacterized by a 20% lower mechanical resistance to unconfined uniaxial compression (UCS). The Tutor of the Project commented positively the achievements obtained in the first year of the project, but argued that solid state NMR was a too expensive and complex method to assess the degree of activation of MKA, and invited the partners to find a simpler and easy method to measure this parameter in an industrial production environment. This suggestion, that would have greatly improved the meaning of the results obtained in the first year of the project, was accepted by all partners, who decided to include this new activity in the second year of the project, in addition to those foreseen in the tasks and deliverables originally defined in the Project. This additional part will be described in a specific Section named ADDITIONAL ACTIVITY OF THE PROJECT that will be added at the end of the results and deliverables obtained in the original WP's, that were aimed at showing the possibility to make K-based geopolymers from the welded (PTV) and lithified volcanic tuff (TRSNV) selected and certified in the first year of activity. The rational of using volcanic tuffs in the second year of the Project to get geopolymeric binders of various types was justified not only by economical and environmental reasons, but also by the need to meet the requirements for a sustainable environment according to the objectives indicated by the EU for the year 2020. In the document issued by the EU Commission, the use of waste materials to make new cementing products characterized by a longer durability and/or low CO2 consumption is one of the main objectives indicated to make a more sustainable environment. In this respect, volcanic tuffs can be advantageous as they are much less expensive than MKA. They are quarried in larger amounts in Italy and substantial portions of them are represented by waste residues from these indutrial activities. Not only the utilization at an industrial scale of volcanic tuffs would have created positive environmental and social benefits by reducing the costs of storage and disposal of wasted material, but also it would become a part of a green economy due to the limited amounts of CO2 required for their production.
SECOND YEAR SCIENTIFIC REPORT OF THE MECAGEOPOLY PROJECT: "MECHANO-CHEMISTRY: AN INNOVATIVE PROCESS IN THE INDUSTRIAL PRODUCTION OF POLY-SIALATE (PS) AND POLY-SILANOXOSIALATE (PSS) GEOPOLYMERIC BINDERS TO BE USED IN BUILDING CONSTRUCTION"
Piero Ciccioli;Paolo Plescia;Sabrina Gualtieri;Giorgio Contini
2014
Abstract
The MECAGEOPOLY Project was aimed at proving that: a) the mechano-chemical activation of kaolins is a valid alternative to the thermal treatment at 650-750°C for the industrial production of PSS geopolymeric binders to be used in building construction and in other industrial applications; b) geopolymeric binders obtained by mechano-chemical activation of kaolins have similar properties than those obtained by thermal treatments; c) the mechano-chemical treatment can be exploited for making geopolymeric binders from other alumino-silicate rocks, such as quarry wastes of volcanic tuff cemented by glass (welded tuffs) or by authigenic minerals (zeolites), that are difficult or impossible to activate by thermal processes; d) the mechano-chemical process is easier to control than the thermal process and it is feasible at an industrial scale; e) the mechano-chemical treatment simplifies the industrial production of PSS geoplymeric binders by combining in a single step the grinding and thermal treatment of the raw material. These objectives were expected to be met in a time period of 2 years, after an evaluation of the results obtained in the first year of activity, aimed at demonstrating the suitability of the mechano-chemical processing to get metakaolins (MKA's) from a commercial kaolin (BS-4) sufficiently reactive for the synthesis of KPSS geopolymers. Although the main objectives of the first year were reached, the reactivity of mechanically activated MKA from BS-4 was higher than that of MKA from BS-4 obtained by thermal treatment. This produced more porous KPSS geopolymers, that showed slightly better thermal properties than KPSS obtained from MKA obtained by thermal treatment, but werecharacterized by a 20% lower mechanical resistance to unconfined uniaxial compression (UCS). The Tutor of the Project commented positively the achievements obtained in the first year of the project, but argued that solid state NMR was a too expensive and complex method to assess the degree of activation of MKA, and invited the partners to find a simpler and easy method to measure this parameter in an industrial production environment. This suggestion, that would have greatly improved the meaning of the results obtained in the first year of the project, was accepted by all partners, who decided to include this new activity in the second year of the project, in addition to those foreseen in the tasks and deliverables originally defined in the Project. This additional part will be described in a specific Section named ADDITIONAL ACTIVITY OF THE PROJECT that will be added at the end of the results and deliverables obtained in the original WP's, that were aimed at showing the possibility to make K-based geopolymers from the welded (PTV) and lithified volcanic tuff (TRSNV) selected and certified in the first year of activity. The rational of using volcanic tuffs in the second year of the Project to get geopolymeric binders of various types was justified not only by economical and environmental reasons, but also by the need to meet the requirements for a sustainable environment according to the objectives indicated by the EU for the year 2020. In the document issued by the EU Commission, the use of waste materials to make new cementing products characterized by a longer durability and/or low CO2 consumption is one of the main objectives indicated to make a more sustainable environment. In this respect, volcanic tuffs can be advantageous as they are much less expensive than MKA. They are quarried in larger amounts in Italy and substantial portions of them are represented by waste residues from these indutrial activities. Not only the utilization at an industrial scale of volcanic tuffs would have created positive environmental and social benefits by reducing the costs of storage and disposal of wasted material, but also it would become a part of a green economy due to the limited amounts of CO2 required for their production.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
