Separation and Purification of β‐Carotene from Chlorophyll Factory Residues

A process for the separation and purification of β‐carotene from chlorophyll factory residues has been developed. By use of three‐step extractions using ethanol, hexane‐NaCl aqueous solution and hexane‐95 % methanol, β‐carotene was enriched up to 0.23 % with a recovery of 79.6 %. The performance and separation characteristics relevant to β‐carotene were measured on HZ816, H103, D4006, HZ801, X5, S8, AB8 and D301 resins. It was found that the non‐polar macroporous X5 resin offers the largest adsorption capacity among the tested adsorbents. The Langmuir and Freundlich adsorption models were applied to describe the multicomponent isotherms of the crude residue, and the experimental data fits best to the Freundlich isotherm. Dynamic adsorption and desorption tests were performed to optimize the β‐carotene separation process on a packed‐bed X5 column. The parameters for dynamic adsorption include a β‐carotene sample solution concentration of 174.5 μg/mL, processing volume of 5 BV, flow rate of 0.5 BV/h, and a temperature of 25 °C. The β‐carotene was eluted entirely from the column following treatment with a gradient elution of ethanol‐ether. The content in the product increased from 0.23 % to 2.03 %, with a recovery yield of 76.6 %. It was then recrystallized in chloroform‐ethanol to obtain a final crystalline product with a purity of 95 %.