A novel process for rutin recovery from model solutions using nanofiltration: Experimental study, mathematical modeling, and scale-up design

Pressure-driven membrane processes represent a credible method for the separation and concentration of natural polyphenols. The separation characteristics and their productivity depend on several factors such as molecular weight cut-off, operating conditions, and test cell parameters. In this study, a compact polyamide HFT-NF150 nanofiltration membrane has been tested to separate different model solutions of rutin, and the effects of operating conditions like trans-membrane pressure, feed concentration, and feed flow rates were analyzed. All the findings of the experiment revealed that the maximum permeate flux of 3.04 x 10-5 m3/m2 s and 98.5% rejection were obtained at a high feed flow rate of 36 L/h and a high pressure of 6 x 105 Pa. Also, the Spiegler-Kedem model is used to report the mass transport phenomenon across the membrane. The unconstrained minimization technique based on the simplex search method was applied for the estimation of the unknown parameters. The theoretical and experimental values for permeate characteristics were then compared for each experimental data point for the model validation. Later, a mathematical model was used to check the scale-up viability of the process to the commercial limit.Practical applicationsIn the past few years, naturally occurring bioactive compounds have revolutionized the whole scientific community for their exploration. Rutin is one such phenolic compound that is present in significant amounts in buckwheat and has a wide range of applications in the food and pharmaceutical industries. In this work, an energy-efficient and cleaner method of nanofiltration is applied to concentrate the rutin from the model plant extract. Experiments were performed on a polyamide nanofiltration membrane with a molecular weight cut-off of 150 Da at different operating conditions. Experimental results were fitted in a three-parameter Spiegler-Kedem model to determine the transport parameters of the membrane for rutin. The values of transport parameters were also successfully validated using the experimental results. Experimental results and model predictions were then used to analyze the effects of different operating parameters. A scale-up setup has been designed and simulated to check the feasibility of the process at the commercial level. Energy-efficient and cleaner method of nanofiltration is applied to concentrate the rutin from the model plant extract. A scale-up setup has been designed and simulated to check the feasibility of the process at the commercial level. image