Journal ArticleDOI
Conversion of lactic acid to acrylic acid in near-critical water
Carl T. Lira,Perry J. McCrackin +1 more
TLDR
In this paper, the degradations of lactic acid in a Hastelloy C-276 annular reactor in near-critical water were investigated at a pressure of 310 bar, at temperatures of 120-400°C, at residence times of 25-110 s, and with various catalysts, including disodium hydrogen phosphate, phosphoric acid, and sodium hydroxide.Abstract:
The dehydration of lactic acid is studied in a Hastelloy C-276 annular reactor in near-critical water. Experiments are performed at a pressure of 310 bar, at temperatures of 120-400°C, at residence times of 25-110 s, and with various catalysts, including disodium hydrogen phosphate, phosphoric acid, and sodium hydroxide. Three main reaction pathways are investigated and evaluated. A temperature of 160°C optimizes the formation of acrylic acid with molar yields as high as 58%, based on conversion. The presence of phosphate salts and/or base increases the yields of acrylic acid by suppressing the competing pathways. The aging of the Hastelloy reactor for 60-70 h decreases the degradation reactions resulting in higher yields of acrylic acidread more
Citations
More filters
Journal ArticleDOI
Lactic acid as a platform chemical in the biobased economy: the role of chemocatalysis
TL;DR: In this article, a critical overview of all advances in the field of homogeneous and heterogeneous catalysis and recognises a great potential of some of these chemocatalytic approaches to produce and transform lactic acid as well as some other promising α-hydroxy acids.
Journal ArticleDOI
Biomass Conversion in Water at 330−410 °C and 30−50 MPa. Identification of Key Compounds for Indicating Different Chemical Reaction Pathways
Andrea Kruse,A. Gawlik +1 more
TL;DR: In this article, the degradation of biomass was studied in the ranges of 330−410 °C and 30−50 MPa and at 15 min of reaction time, and the chemistry of biomass degradation, key compounds which are interme...
Journal ArticleDOI
Catalytic dehydration of glycerol in sub- and supercritical water: a new chemical process for acrolein production
TL;DR: In this paper, the influence of the addition of electrolytes such as zinc sulfate on this reaction has been investigated and it was shown that in the near subcritical temperature, increasing the amount of salt enhances the glycerol conversion.
Book
Analytical Supercritical Fluid Extraction
Miguel Valcárcel,Miguel Valcárcel,Maria T. Tena,M. D. Luque de Castro,María Teresa Tena,María Dolores Luque de Castro +5 more
TL;DR: In this paper, the authors present an analytical approach for the separation of supercritical fluids in the analytical process, based on a set of properties of the supercritical fluid, including: 1.1 Basic Features of the Supercritical Fluid.
Journal ArticleDOI
Catalytic routes towards acrylic acid, adipic acid and ε-caprolactam starting from biorenewables
TL;DR: The types of today's biomass sources and their economical relevance are summarised, and the biobased productions of three important bulk chemicals: acrylic acid, adipic acid and e-caprolactam are assessed.