Renewable acrylonitrile production

TLDR

Acrylonitrile (ACN) is a petroleum‑derived compound used in resins, polymers, acrylics, and carbon fiber. The study presents a renewable ACN production process using microbially derived 3‑hydroxypropionic acid from sugars. The process employs ethyl 3‑HP dehydration and nitrilation over inexpensive TiO₂ solid‑acid catalyst to achieve >90 % ACN yields, and a scaled integrated version yields 98 ± 2 % from ethyl acrylate. The endothermic route eliminates runaway hazards, yields higher ACN than propylene ammoxidation, and avoids toxic HCN by‑product, improving safety and handling.

Abstract

Acrylonitrile (ACN) is a petroleum-derived compound used in resins, polymers, acrylics, and carbon fiber. We present a process for renewable ACN production using 3-hydroxypropionic acid (3-HP), which can be produced microbially from sugars. The process achieves ACN molar yields exceeding 90% from ethyl 3-hydroxypropanoate (ethyl 3-HP) via dehydration and nitrilation with ammonia over an inexpensive titanium dioxide solid acid catalyst. We further describe an integrated process modeled at scale that is based on this chemistry and achieves near-quantitative ACN yields (98 ± 2%) from ethyl acrylate. This endothermic approach eliminates runaway reaction hazards and achieves higher yields than the standard propylene ammoxidation process. Avoidance of hydrogen cyanide as a by-product also improves process safety and mitigates product handling requirements.