Solubility study could impact energy, biology, environment

September 5, 2017, Rice University

Rice University chemical engineers have used the most realistic computer model yet devised to simulate the precise atomic and molecular interactions that come into play when water mixes with alkanes, a family of hydrocarbons that includes methane, propane and other products refined from petroleum and natural gas, such as paraffin.

In a new study published this month in the Journal of Chemical Physics, Rice researchers Dilipkumar Asthagiri, Arjun Valiya Parambathu and Walter Chapman, as well as former graduate student Deepti Ballal of Ames Laboratory, offered new answers to a puzzle that has long stymied chemists: When calculating the expected attraction between water and alkane molecules in an alkane-rich solution, scientists find that their answers don't jibe with experimental results.

Asthagiri and colleagues demonstrated that underlying electrostatic and polarization effects—things considered inconsequential in conventional approaches—are critical for accurate simulation of water-alkane solubility.

Chapman, the William W. Akers Professor of Chemical and Biomolecular Engineering and associate dean of engineering for energy, said the research could have far-reaching impacts in fields as diverse as biology, environmental systems and energy and chemical production.

"Simulations are increasingly used to understand, and potentially to manipulate, processes at the nanoscale," Chapman said. "For example, our results could offer new insight to those who study free-energy surfaces related to protein folding and protein denaturation. They could be helpful in better interpreting MRI scans and in predicting the fate of contaminants in the environment. In energy production, insights from this work could be useful for improving flow assurance, preventing corrosion and improving processes in other ways that reduce costs and environmental impacts."

Chapman said his group hopes to build upon the work with future models that incorporate quantum corrections to both the movement of the particles and in assessing interatomic interactions, something that's only become feasible through recent advances in both parallel computing and linear-scaling quantum calculations.

Explore further: Team takes deeper look at unconventional oil and gas

More information: D. Asthagiri et al, Electrostatic and induction effects in the solubility of water in alkanes, The Journal of Chemical Physics (2017). DOI: 10.1063/1.4997916

Related Stories

Team takes deeper look at unconventional oil and gas

February 9, 2017

Understanding how oil and gas molecules, water and rocks interact at the nanoscale will help make extraction of hydrocarbons through hydraulic fracturing more efficient, according to Rice University researchers.

Models will enable safer deepwater oil production

April 1, 2013

Rice University researchers are developing a comprehensive model that will predict how brine, oil and gas drawn from ultra-deep wells react to everything encountered on the way up to the surface and to suggest strategies ...

Recommended for you

A better HIV test

January 22, 2018

Public health officials have a tough choice to make when it comes to screening people for HIV: administer a reliable blood test that can detect infections early on, but that few people will volunteer for, or give people a ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.