Sugar cane bagasse is an industrial waste which is used worldwide as fuel in the same sugarcane industry. The combustion yields ashes containing high amounts of unburned matter, silicon and aluminium oxides as main components. These sugar-cane bagasse ashes (SCBA) have been chemically, physically and mineralogically characterized, in order to evaluate the possibility of their use as a cement-replacing material in the concrete industry. Determination of parameters such as carbon content (by thermal analysis methods), presence of crystalline material (by X-ray diffractometry), granulometric distribution (by laser diffraction in water suspensions), morphology of particles (by scanning electron microscopy) and reactivity towards lime (pozzolanic activity by thermogravimetric monitoring in lime/SCBA and cement/SCBA pastes) have been carried out.

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Use of functionalized MCM‐41 solids as anion sensing systems has been demonstrated for the first time. The combination of the binding properties of molecular receptors with the structural characteristics of solid, inorganic surfaces leads to remarkably enhanced anion sensing response. The Figure shows a schematic view of a solid surface, with 300 Å diameter holes that are filled with aminoanthracene molecules.

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CO 2 emissions associated with geopolymeric mortar prepared using spent fluid catalytic cracking catalyst (FCC) were compared to those calculated for plain ordinary Portland cement (OPC) mortar.Commercial waterglass used for preparing alkaline activating solution for geopolymeric mortar was the main contributing component related to CO 2 emission. An alternative route for formulating alkaline activating solution in the preparation of the geopolymeric binder was proposed: refluxing of rice husk ash (RHA) in NaOH solution. Geopolymeric mortar using rice hull ash-derived waterglass led to reduced CO 2 emission by 63% compared to OPC mortar. The new alternative route led to a 50% reduction in CO 2 emission compared to geopolymer prepared with commercial waterglass.Replacement of commercial waterglass by rice hull ash-derived waterglass in the preparation of the geopolymer did not cause a significant decrease in the mechanical strength of mortar. CO 2 intensity performance indicators (C i ) for geopolymeric mortars were lower than that found for OPC mortar, indicating that the new route for activating solution led to the lowest C i value.

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