Dehydration of Lactic Acid: The State of The Art

Abstract

The dehydration of lactic acid to produce acrylic acid is a renewable alternative to the mostly used production of acrylic acid from propene. In this review, the recent developments and state of the art for the dehydration of lactic acid to acrylic acid are presented and critically commented. The most recent publications on the topic are discussed inetail with respect to the observed catalysts and process performance data. Among the different catalysts developed, three main groups can be distinguished: zeolites, sulphates, and phosphates. The latter, especially hydroxyapatites, have recently attracted the attention of academics in particular. The three families of catalysts are discussed and the recent developments and technical drawbacks in the gas phase dehydration are reported.

Design of Co, Cu and Fe–BEA Zeolite Catalysts for Selective Conversion of Lactic Acid into Acrylic Acid

“…Pérez-Ramírez et al [18] also studied the LA dehydration process using hierarchical NaY zeolite, which exhibited a high selectivity to AA (75%). Important issues on the dehydration of LA were also presented by T. Bonnotte et al [19].…”

Synthesis of Acrylonitrile from Renewable Lactic Acid

“…Such a cyclic transition state could be reached on the surface of carbonates, nitrates, phosphates, or sulfates. Especially the latter two are promising because BaSO 4 and various phosphates are used in the dehydration of LA to acrylic acid. The dehydration of the alcohol group in LCM is similar as shown in Scheme .…”

“…In the Ac 2 O-assisted dehydration of LCM it became clear that the elimination of acetic acid in ac yclic transitions tate is the crucial step in the mechanism. The CÀHa nd CÀOb onds are broken simultaneously,a nd no chargedi ntermediates are generated[ Scheme 5( left)].S uch ac yclic transition state could be reached on the surfaceo fc arbonates, nitrates, phosphates, or sulfates.E specially the latter two are promisingb ecause BaSO 4 [48] and various phosphates [49] are used in the dehydration of LA to acrylic acid. The dehydration of the alcohol group in LCM is similara ss hown in Scheme 5.…”

Bio‐Acrylates Production: Recent Catalytic Advances and Perspectives of the Use of Lactic Acid and Their Derivates

“…However, the conversion of LA to AA is the most widely studied route. Although several reviews describe the LA‐to‐AA chemical route,,, together with a discussion about the reaction mechanisms, we are aiming for a more structured updated summary of the existing literature on this LA‐to‐AA reaction and we will present a clear separation of lactic acid based studies from those based on derivatives of lactic acid. As these are often reported together, they may hide potential problems with the catalytic performances related to the nature of the feedstock.…”