Acrylic Acid Production via Lactide Pyrolysis
Solution Overview
Problem
Current production of technical grade acrylic acid is costly due to high capital and raw material expenses, and existing methods for producing acrylic acid via fermentation are inefficient, with low yields from lactic acid dehydration.
Innovation Solution
A process using a nickel catalyst system with lactide and methyl acetate to convert 2-acetoxypropionate, followed by pyrolysis and transesterification, achieving high yields of acrylic acid and methyl acrylate, with recycling of reactants to optimize production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional two-stage air oxidation of propylene is used to produce acrylic acid, then production capacity is achieved, but capital cost and raw material cost are very high
Solution Approach 1:
The invention changes the chemical pathway parameters by using fermentation-derived lactic acid as feedstock instead of propylene, and employs pyrolysis temperature and catalyst parameters to achieve high-yield acrylic acid production through a different chemical route that avoids the expensive oxidation catalysts and high-pressure equipment
Solution Approach 2:
The invention uses inexpensive, readily available materials such as fermentation-derived lactic acid feedstock and simple pyrolysis catalysts (zeolites, alumina, silica) instead of expensive proprietary oxidation catalysts, replacing costly shell-and-tube reactors with simpler pyrolysis reactor designs
2Productivity
If lactic acid dehydration is used to produce acrylic acid via fermentation, then renewable resource utilization is achieved, but yield is low at approximately 55%
Solution Approach 1:
The invention changes the reaction parameters by using pyrolysis temperatures (typically 300-700°C) and catalyst properties instead of conventional dehydration conditions, transforming the reaction mechanism to proceed through radical pathways rather than carbocation intermediates, thereby achieving near-quantitative yields
Solution Approach 2:
The invention substitutes the conventional acid-catalyzed dehydration mechanism with a thermal pyrolysis mechanism, replacing the need for acid catalysts and their associated side reactions with thermal energy-driven bond cleavage and reformation that proceeds through different intermediates and achieves higher selectivity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This process enhances the efficiency and cost-effectiveness of acrylic acid and methyl acrylate production by achieving high conversions and allowing for the recycling of reactants, thereby reducing production costs and improving yield.
Implementation Method 1
A process using a nickel catalyst system with lactide and methyl acetate to convert 2-acetoxypropionate
Implementation Method 2
followed by pyrolysis and transesterification, achieving high yields of acrylic acid and methyl acrylate
Implementation Method 3
followed by pyrolysis and transesterification, achieving high yields of acrylic acid and methyl acrylate
Data Source
AI summary
Technical grade acrylic acid derived from renewable resources utilizing a homogeneous nickel catalyst system by a process including reacting lactide with acetic acid to form 2-acetoxypropionic acid in the presence of a homogeneous nickel catalyst, pyrolyzing, with or without a catalyst, the 2-acetoxypropionic acid to acrylic acid and acetic acid, condensing and collecting the pyrolysis products in the presence of polymerization inhibitor(s) and purifying the acrylic acid by distillation in the presence of polymerization inhibitor(s). Acrylic acid and methyl acrylate are produced from methyl 2-acetoxypropionate which comes from fermentation derived lactic acid. The disclosed process will produce a “green” (i.e. renewable resources derived) acrylic acid and methyl acrylate ester.