New alloy resists dusting

Materials developed by scientists at the US Department of Energy's Argonne National Laboratory could provide large cost and energy savings to the chemical and petrochemical industries.

The new alloy materials are said to be resistant to metal dusting, a type of degradation that occurs at elevated temperatures in hydrocarbon-containing atmospheres in which carbon activity is high.

Such environments are prevalent in chemical and petrochemical industries such as hydrogen, methanol-and ammonia-reformers and in synthesis gas production plants. The degradation of metallic component materials into powder and the resulting damage make it difficult to maintain equipment used in these industries. Currently, almost all commercial alloys degrade by metal dusting corrosion.

'More than 50 years of previous research could not solve this problem,' said Argonne researcher Ken Natesan. 'The only available solution was to quench the high-temperature gases by lowering the working temperature, which results in energy loss and decreased product yield.'

In a study lasting several years, Natesan and Argonne researcher Zuotao Zeng established the role of carbon deposition in the mechanism leading to initiation and propagation of metal dusting. The work was conducted at atmospheric and high pressures and simulated the gas chemistry, including the high steam content prevalent in reformer environments.