Acrylic acid process parameters

This work presents an analysis of kinetic parameters, used in a dynamic structured model for the acrylic acid production process. Through this procedure, it was possible to identify the parameters with the most significant impact on the model to represent well the process of acrylic acid production. 

Equation (Rs) corresponds to the biomass formation from lactate, where a glucose inhibition term is included in the equation. Equation (R ) describes the formation of lactate dehydrogenase from active component in the cell material (X ). An acrylic acid inhibition term was added in this equation. Equation (Rt) shows the degradation rate of the active compartment and depends of the glucose and acrylic acid present in the medium. These reaction rates and the kinetic parameters values were obtained from Lei et al. [4] and modified to describe the acrylic acid production process. 

To analyze the operational parameters used in the acrylic acid production process, a fractional factorial design of two-level (2 ) with two level of fractionation was used. In this experimental design, six variables (Si , Fi , Xj , Dp, D and L) were investigated in 16 runs. The values of such parameters are shown in Table 7, whereas Table 8 depicts the coded units of parameters and the obtained response in each simulation (colurim 8). The obtained results are shown in Pareto chart (Fig. 7). 

Through these experimental designs, it is possible to identify the optimal values of the parameters to increase the acrylic acid concentration from biotechnological process (inside of value range established for this process). Table 9 shows the optimal condition settings of factors. 

In this work, the kinetics and operational parameters used in the acrylic acid production from biotechnological process were analyzed, bearing in mind that high operational... 

Later on, through fractional factorial design, the operational parameters with a significant impact in the process were identified. In addition, it was possible to identify the optimal values for kinetic and operational parameters. The optimal values of such parameters identified in these experimental designs are able to drive the process to maximize the acrylic acid concentration. 

Vapor phase polymerization from SI-NMP of various vinylic monomers resulted in polymer bmshes with greater thicknesses than those formed by the solution phase process [21]. To explain this result, the authors supposed a more efficient reaction on the surface as a result of prolongation of the mean path of vaporized monomers in a vacuum, higher thermal energy of the monomer, and the possibility of adjusting the reaction parameters independently. Thin films of PS grafted polymer, poly (acrylic acid) (PAA), poly(2-hydroxypropyl methacrylamide) (PHPMA), and poly(lV-isopropylacrylamide) (PNIPAM) were prepared with thicknesses of a few nanometers to submicrometers. This process was also used for the preparation of block copolymers (e.g., PS-b-PAA and PAA-b-PS-PHPMA). It is important to mention that solution phase polymerization of AA, HPMA, and NIPAM is impossible with TEMPO-based alkoxyamines. 

Copolymerization. Vinyl chloride can be copolymerized with a variety of monomers. Vinyl acetate [9003-22-9], the most important commercial comonomer, is used to reduce crystallinity, which aids fusion and allows lower processing temperatures. Copolymers are used in flooring and coatings. This copolymer sometimes contains maleic acid or vinyl alcohol (hydrolyzed from the poly(vinyl acetate)) to improve the coating s adhesion to other materials, including metals. Copolymers with vinylidene chloride are used as barrier films and coatings. Copolymers of vinyl chloride with maleates or fumerates are used to raise heat deflection temperature. Copolymers of vinyl chloride with acrylic esters in latex form are used as film formers in paint, nonwoven fabric binders, adhesives, and coatings. Copolymers with olefins improve thermal stability and melt flow, but at some loss of heat-deflection temperature (100). Copolymerization parameters are listed in Table 5. 

---