(195i) Designing Inhibitors of Mineral Scale: A New Platform Based on Cooperative Microfluidic Assays and in Situ Atomic Force Microscopy

Sosa, R. D., University of Houston
Geng, X., University of Houston
Palmer, J. C., University of Houston
Reynolds, M. A., Shell Exploration and Production Company
Conrad, J. C., University of Houston
Rimer, J. D., University of Houston
Mineral scale occurs in processes ranging from water treatment and purification to oil and gas production systems, posing significant challenges to the upstream petroleum industry. Designing effective biodegradable chemical treatments to reduce scale formation requires understanding the molecular-scale interactions of inhibitors during nucleation and growth of scale. Here we apply new approaches to design and test environmentally friendly inhibitors of scale formation using a combination of surface science techniques, microfluidic technology, and molecular modeling. Crystallization can be inhibited in highly supersaturated solutions using dilute quantities of macromolecular modifiers. How the presence of flow, which alters the dynamics of modifier-crystal interactions, affects inhibitor efficacy is not fully understood. Our studies focus on barium sulfate (barite), a common scaling mineral. In this presentation we will describe a microfluidic platform that is used to perform multiple bulk crystallization assays simultaneously and capture crystal growth and inhibition in real time in the presence of biomacromolecules. Using in-situ scanning probe microscopy, we probe the interfacial behavior between the biomacromolecules and different surfaces of barite and elucidate the role of these putative inhibitors during the growth phase of mineralization. Concurrently, we use molecular modeling of inhibitor adsorption of barite surfaces to probe the interactions that govern inhibitor specificity and efficacy. Collectively, these studies generate new understanding of the mechanism(s) of crystal growth modifiers and apply this knowledge to design improved generations of scale inhibitors.