아미노산과 중금속 이온 혼합물의 연속적인 분리를 위한 최적의 simulated moving bed와 carousel 공정 개발

Abstract

In this study, two different patterns of continuous chromatographic separation processes for the production of valuable amino acids and heavy metal ions were developed in a systematic way. First, a modified four-zone simulated moving bed (SMB) process for separation of a ternary amino acid mixture was established in order to address the need for fractionation of the amino acid mixture coming from upstream fermentation steps, which has been widely raised in a lot of biochemical industries. The development procedure of modified four-zone SMB started with estimating intrinsic parameters of three amino acids. These intrinsic parameters were applied in optimization step of modified four-zone SMB process, which was carried out using a highly efficient SMB optimization tool that was prepared based on genetic algorithm. The optimized modified four-zone SMB process was validated first from detailed rate-model simulations and then from a well-organized SMB process experiment. The experimental results of MF-SMB showed verified the attainment of a ternary separation. Secondly, an efficient method for determining the optimal size of adsorbent particle in SMB process was developed to meet the necessity for maximizing the SMB productivity. For this work, a series of electronic packages based on the standing wave design theory was constituted and further improved to immediately produce the optimal particle size with high accuracy. It was confirmed that the developed methodology and electronic tool were highly effective in optimizing the particle size of the SMB process for amino acid separation. Following the above SMB process development for amino acid separation, another type of continuous separation process, a carousel process, was developed for continuous recovery of the target metal ion from a mixture of heavy metal ions. For the recovery of specific metal ion, a metal ion-imprinted polymer (MIP), which has strong affinity to target metal ion, was specially synthesized and utilized as a solid phase in the carousel process of interest. Moreover, two different configurations of carousel process were properly designed according to species of eluent in separation zone. The operating conditions of these carousel processes were determined from a series of single-column experiments and detailed simulations. The experiment results of both carousel processes showed that the target heavy metal ion could be recovered with high purity and high yield through proposed carousel processes in a continuous mode. The results and the design approach in this work will make a valuable contribution to the downstream step in metal-plating industries or semiconductor industries and furthermore to the industries involved in the recovery of rare-earth metals.