Vivek Mehrotra

Sacrificial Protective Coating Materials that can be Regenerated In-Situ to Enable High Performance Membranes

Among the various manufacturing processes employed across all U.S. industries, the process of concentrating weak black liquor (WBL) in the pulp and paper industry is identified as one of the largest energy reduction opportunities for separation technologies. The concentration of WBL in the pulping process is currently performed by multiple stages of steam-heated evaporators, which concentrate the liquor from approximately 15% solids to about 65%–80% solids. This process consumes large amounts of energy due to the high heat needed to vaporize water.

Bio Inspired Living Skins for Fouling Mitigation

A biomimetic method to mitigate marine biofouling using a pilot-whale inspired sacrificial skin concept has been developed. We developed a method to form conformal, protective skins in-situ underwater using a circulatory system. In addition, the materials chemistry was tuned such that the skin dissolves after a tunable stable period, removing any foulants that may have collected on it. A very large reduction in biofouling was demonstrated for surfaces protected by the sacrificial skin compared to identical unprotected surfaces, when high fouling pressure was generated using bacteria in artificial seawater. Skin formation, stability, and dissolution have been studied by forming skins on 6 inch square flat substrates, and curved surfaces. Several different materials and material combinations were tested for their skin-forming ability. Rheology studies were conducted to determine the changes in viscosity of the materials upon exposure to seawater. The materials microstructure and composition was probed before and after seawater exposure. These experiments helped explain the mechanisms by which skin formation and dissolution occurs. Biofouling experiments consisted of culturing and growing the bacteria Pseudoalteromonas carrageenovera, a strain known to cause biofouling in marine environments. Efforts focused on determining experimental conditions necessary to achieve high levels of biofouling growth in the shortest amount of time. Marine-like environments were created in the range of a few hundred milliliters of artificial seawater and scaled to several liters, large enough to contain a 6 inch × 6 inch substrate.Copyright