ExxonMobil introduces renewable diesel process

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ExxonMobil Catalysts and Licensing has introduced ExxonMobil Renewable Diesel (EMRD) process technology, to help meet evolving mobility needs using renewable feedstock.

EMRD converts feedstocks including vegetable oils, unconverted cooking oils, and animal fats into renewable diesel. It is a two-stage process in which hydrotreating and dewaxing are controlled separately. Stage 1 comprises hydrodeoxygenation to convert triglycerides to n-paraffins. In Stage 2, the n-paraffins are selectively isomerised to iso-paraffins, improving the cold flow properties. Exxon says that compared to a single-stage process, this method enables higher yield and better control.

The process technology uses Exxon’s Bio-isomerisation Dewaxing Catalyst (BIDW) catalyst. According to Exxon, during testing, BIDW demonstrated better yields compared to other internally formulated zeolite-based alternatives. It offers effective dewaxing in both summer and winter modes. Diesel fuel has different seasonal requirements for summer and winter.

EMRD also has the potential to produce jet fuel as a secondary product with added fractionation. Due to significant interest in producing renewable jet fuel as a primary product, Exxon is developing advanced catalyst and process technology that offers the flexibility to tailor the amount of diesel to the amount of jet fuel produced.