Process Engineering for Advanced Chemically Bonded Ceramics (CBC)

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We aim to achieve room- or near-room T processed low-cost, low-CO2 emission Chemically Bonded Ceramics CBC with high-T (> 1000C) resistance and targeted ion encapsulation (e.g. heavy*metals or nuclear waste) properties. (I) room- or near-room-temperature*processing, and (II) use of chemical reactions, rather than sintering, to*achieve ionic/covalently bonded materials, will be utilized. Properly processed*CBC may lead to high-T (>1000C)*resistant ceramics obtained in a low-T (<100C) processes as the chemically reacting CBC form ionic/covalent bond*and undergo phase transformations at elevated T. The kinetics of these processes will be studied to determine the*speed of fire resistance increase of such CBCs exposed to elevated T. Because of the above two fundamentals*(I, II) of CBC processes and their mineral/waste raw materials, their CO2 footprint could be up to 10x smaller as compared to OPC. Specifically, we propose research into advanced CBCs for (A) structural and (B) functional*applications broadly related to environmental*protection, in two Themes 1,2:***Theme*1: Basic and Applied Studies on (1A) Structural and (1B) Functional Acid-Activated*Phospho-Silicate Cements (PhD#1). The long-term objective*is to develop process technology for phosphoric acid bonded mineral-derived,*low-cost low-alkali (Na, K) calcium alumino-silicates (such as anorthite) as (1A) viable replacement of structural OPC, and (1B) functional high-temperature (refractory) ceramics. An overlap between 1A and 1B allows to*obtain in a simple, room-temperature process large volumes of high-temperature*resistant cements for applications in fire-sensitive residential, transportation*(e.g. tunnels), industrial (e.g. petrochemical) or military structures.***Theme*2: Basic and Applied Studies on Alkali-Activated (2A) Structural and (2B) Functional*Geo-Polymers GP (PhD #2). The is focus on low-cost,*room-temperature processing of alkali-activated metakaolinite and waste*materials such as aluminosilicate fly-ash for (2A) structural applications of amorphous, low-CO2 footprint GP targeting general OPC replacement, and (2B) functional applications of microstructurally-engineered,*in-situ zeolite-crystallized GP targeting absorption and retention of Cs, Sr,*As, or heavy metals Pb, Hg.