arXiv subjects

Veena Sahajwalla

Publications and source records attributed to Veena Sahajwalla.

3 recordsLinked to original sources

arXiv2022

Recycling End-of-life Polycarbonate in Steelmaking; $\textit{Ab Initio}$ Study of Carbon Dissolution in Molten Iron

The scarcity of fossil fuels as carbon resources has motivated the steelmaking industry to search for new carbon sources such as end-of-life polymeric products. Using $\textit{ab initio}$ molecular dynamics simulation, we demonstrate that 41% of polycarbonate's carbon content is readily dissolved in molten iron's interface at $T$ = 1823 K which is comparable to graphite with $\sim$ 58% carbon content dissolution. More importantly, we demonstrate that polycarbonate's hydrogen content does not dissolve in molten iron but rather escape in gaseous form. Therefore, waste polycarbonate constitutes a feasible carbon source for steelmaking.

cond-mat.mtrl-sci↗

arXiv2022

High-Density Polyethylene Degradation into Low Molecular Weight Gases at 1823 K: An Atomistic Simulation

Using molecular dynamics simulation, we present a comprehensive study of the volatile thermal degradation of high-density polyethylene (HDPE) across a temperature range of 300 K to 1823 K. We find that degradation at temperatures higher than $\sim$ 1373 K generates significant quantities of reducing gases such as CH$_{\text{n}}$ and hydrogen molecules which are beneficial to the steelmaking industry. Our results provide a new understanding of HDPE's phase transformation from solid to gas that occurs during superheating at steelmaking's electric arc furnace environment offering a new method for eliminating end-of-life HDPE from landfill.

cond-mat.soft↗

arXiv2021

Polymers' surface interactions with molten iron: a theoretical study

Environmental concerns are the chief drive for more innovative recycling techniques for end-of-life polymeric products. One attractive option is taking advantage of C and H content of polymeric waste in steelmaking industry. In this work, we examined the interaction of two high production polymers, i.e., polyurethane and polysulfide with molten iron using ab initio molecular dynamics simulation. We demonstrate that both polymers can be used as carburizers for molten iron. Additionally, we found that light weight H$_2$ and CH$_x$ molecules were released as by-products of the polymer-molten iron interaction. The outcomes of this study will have applications in the carburization of molten iron during ladle metallurgy and waste plastic injection in electric arc furnace.

cond-mat.mtrl-sci↗