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BACKGROUND Spent coffee grounds, a valuable source of phenolic compounds, are considered beneficial for human health because of their antioxidative properties. The liquid extract containing phenolic compounds (such as chlorogenic and gallic acids) can be obtained via extraction using environmentally friendly organic solvent. The separation of chlorogenic and gallic acids from the liquid extract was carried out using isocratic chromatography technique in a three‐zone simulated moving bed (SMB). However, due to the low selectivity of separation, the productivity of three‐zone SMB was sacrificed to meet the purity criteria. Hence this work aimed to enhance the productivity of three‐zone SMB for the separation of chlorogenic and gallic acids via model simulation using partial feed operation and to improve the concentration of extract and raffinate products using partial collection strategy. RESULTS The full feed scenario was designed based on the triangle theory, and the partial feed patterns (initial feed, middle feed and late feed) were implemented for each operating point in the triangle diagram to investigate the possibility of increasing the feed flow rate. The maximum productivity was evaluated based on the purity criteria (≥98%) for both extract and raffinate products. Under optimal conditions, productivity was doubled to 0.24 mg min−1 L−1 for both middle feed and late feed patterns compared to that of the full feed scenario. The partial collection strategy applied to the optimal point for each operational mode significantly increased the raffinate concentration to approximately 0.02 g L−1 at the optimal time fraction for discarding the solvent. CONCLUSION This work could be a foundation for the valorization of spent coffee ground. © 2021 Society of Chemical Industry (SCI).

Encapsulation of vitamin E is the preservation of the biological activities of vitamin E for various applications. In the first part of this research, factors affecting the batch encapsulation of vitamin E, including PCL concentration, the concentration of Tween 20, and the volumetric ratio of aqueous phase to organic phase were experimentally investigated. The Box-Behnken experimental design and response surface methodology were implemented to determine the optimal operating conditions of the batch encapsulation. At the optimal conditions, the percentage of vitamin E encapsulation (%EC) was 98.69%, using the PCL concentration, the Tween 20 concentration, and the volumetric ratio of aqueous phase to organic phase of 3.6 g/L, 0.6 g/L, and 0.9 mL: 1 mL, respectively. The second part is to enhance the productivity by applying the optimized formulation of vitamin E encapsulation in a continuous process using a micro-channel encapsulator. The effect of residence time was investigated. At the residence time of 1 s, the percentage of vitamin E encapsulation of 97.28% and the productivity of 153.61 mg/(mL∙min) were achieved.