SUPERCRITICAL CO₂ AS A GREEN SOLVENT: A COMPREHENSIVE REVIEW OF ITS APPLICATIONS IN INDUSTRIAL PROCESSES

Abstract

Supercritical carbon dioxide (scCO₂) has emerged as a powerful green solvent with broad applications across various industrial domains due to its tunable solvating power, low toxicity, and environmentally benign characteristics. This study presents a systematic literature review of 163 peer-reviewed articles published between 2000 and 2024, conducted in accordance with the PRISMA 2020 guidelines to ensure a structured, transparent, and comprehensive evaluation process. The objective of this review is to critically examine the role of scCO₂ in facilitating sustainable and high-performance processing across multiple sectors, including natural product and bioactive compound extraction, pharmaceutical formulation and purification, polymer processing, green chemical synthesis, environmental remediation, and industrial waste management. The findings demonstrate that scCO₂ consistently offers superior extraction efficiencies, enhanced drug solubility and bioavailability, clean and controlled polymer modification, improved catalytic reaction selectivity, and effective removal of persistent organic pollutants and recovery of valuable resources from waste streams. Notably, case studies from global industry leaders such as Nestlé (coffee decaffeination), Pfizer (pharmaceutical micronization), and BASF (polymer coating and impregnation) provide concrete evidence of scCO₂’s successful industrial adoption and economic feasibility. In addition to performance metrics, the review identifies key engineering challenges related to high-pressure reactor design, pump and separator integration, process control, and safety management, all of which are addressed through advanced modeling, material innovation, and automation strategies. By synthesizing multidisciplinary research and real-world implementation, this review positions scCO₂ not only as a sustainable alternative to conventional solvents but also as a mature industrial technology with transformative potential in advancing green manufacturing and circular economy practices.