# Green Coconut Biorefinery: RSM and ANN–GA Optimization of Coconut Water Microfiltration with IntegratedTechno-Economic Analysis

## TL;DR

This paper optimizes coconut water microfiltration using advanced modeling and evaluates the economic feasibility of a green coconut biorefinery.

## Contribution

The study introduces a novel integration of RSM and ANN–GA for optimizing microfiltration and provides a techno-economic analysis for a coconut biorefinery.

## Key findings

- Optimized microfiltration achieved 605.32 ± 15.34 L h−1 m−2 flux and 82.79 ± 1.35% VRR at 75 kPa and 30 °C.
- Economic analysis showed an IRR of 23.80%, NPV of US$733,761, and a 2.96-year payback period.
- Fouling was primarily due to concentration polarization and intermediate blocking mechanism.

## Abstract

The coconut water market continues to expand, but industrial supply is constrained by the high perishability of fresh coconut water and the need for stabilization routes that preserve quality. This study optimized crossflow microfiltration of coconut water using a silicon carbide (SiC) ceramic membrane, high permeability, chemical/thermal robustness, and cleanability, and assessed the techno-economic feasibility of a green coconut biorefinery producing microfiltered coconut water and coconut pulp. Pressure and temperature were modeled and optimized using a face-centered design (FCD) and artificial neural networks coupled with a genetic algorithm (ANN–GA), considering permeate flux and fouling index (p < 0.05). Both approaches converged to the same operating point, and experimental validation at 75 kPa and 30 °C achieved 605.32 ± 15.34 L h−1 m−2 and 82.79 ± 1.35% at VRR = 1. Sample-level fit statistics favored ANN (higher R2 and lower sample-level errors), whereas condition-wise grouped cross-validation (leave-one-condition-out) indicated higher predictivity and lower RMSECV for the quadratic FCD/RSM models across experimental conditions, highlighting response-dependent generalization within the investigated domain. Fouling analysis indicated concentration polarization as the main resistance contribution and a flux-decline behavior best described by the intermediate blocking mechanism. A SuperPro Designer® simulation over a 20-year project life indicated economic feasibility under baseline assumptions (Internal rate of return—IRR = 23.80%, Net present value—NPV = US$733,761, payback = 2.96 years), with profitability remaining attractive under ±10% selling-price variation. Overall, the process optimization and modeling outcomes align with the economic case, reinforcing the potential of this biorefinery concept for industrial deployment.