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Riman, Richard

Publications and source records attributed to Riman, Richard.

Waste-to-Energy (WTE)-derived Low-Carbon-Footprint Concrete (LCFC)

The construction industry is estimated to generate around 600 million tons of concrete and demolition waste annually in the US. In comparison, Waste-To-Energy (WTE) plants generate about 6.6 million tons of ash from the combustion of municipal solid waste.1–4 Research has been ongoing for decades to upcycle WTE-ash and C&D waste.

36 MATERIALS SCIENCE↗

Lithium aluminum–layered double hydroxide chlorides ( LDH ): Formation enthalpies and energetics for lithium ion capture

Layered aluminum double hydroxide chloride sorbents, LiCl∙Al 2 (OH)6. n H 2 O, Li-LDH, have shown promising application in selective Li extraction from geothermal brines. Maintaining LiCl uptake capacity and retaining a long cycle life are critical to widespread application of sorbent materials. To elucidate the energetics of Li capture, enthalpies of LDH with different Li content have been measured by acid solution calorimetry. The formation enthalpies generally become less exothermic as the Li content increases, which indicates that Li intercalation destabilizes the structure, and the enthalpies seem to approach a limit after the Li content x = 2Li/Al exceeds 1. To improve stability, metal doping of the aluminum LDH structure with iron was performed. Introduction of a metal with greater electron density but a similar ionic radius was postulated to improve the stability of the LDH crystal structure. Here, the calorimetric results from Fe-doped LDH samples corroborate this as they are more exothermic than LDH-lacking Fe. This suggests that Fe doping is an effective way to stabilize the LDH phase.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗