Biphasic pretreatment excels over conventional sulfuric acid in pinewood biorefinery: An environmental analysis

• Published in: Environmental research 2024-05, Vol.248, p.118286-118286, Article 118286
• Main Authors: Khounani, Zahra, Abdul Razak, Normy Norfiza, Hosseinzadeh-Bandbafha, Homa, Madadi, Meysam, Sun, Fubao, Mohammadi, Pouya, Mahlia, T.M. Indra, Aghbashlo, Mortaza, Tabatabaei, Meisam
• Format: Article
• Language: English
• Subjects: Bioenergy; Biofuels; Biomass; Biotechnology - methods; Biphasic pretreatment; Ecosystem; Humans; Hydrolysis; Life cycle assessment; Lignin; Lignocellulosic biomass; Pentanols; Saccharomyces cerevisiae; Sulfuric Acids; Xylonic acid
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2024.118286

This study assesses the environmental impact of pine chip-based biorefinery processes, focusing on bioethanol, xylonic acid, and lignin production. A cradle-to-gate Life Cycle Assessment (LCA) is employed, comparing a novel biphasic pretreatment method (p-toluenesulfonic acid (TsOH)/pentanol, Sc-1) with conventional sulfuric acid pretreatment (H2SO4, Sc-2). The analysis spans biomass handling, pretreatment, enzymatic hydrolysis, yeast fermentation, and distillation. Sc-1 yielded an environmental impact of 1.45E+01 kPt, predominantly affecting human health (96.55%), followed by ecosystems (3.07%) and resources (0.38%). Bioethanol, xylonic acid, and lignin contributed 32.61%, 29.28%, and 38.11% to the total environmental burdens, respectively. Sc-2 resulted in an environmental burden of 1.64E+01 kPt, with a primary impact on human health (96.56%) and smaller roles for ecosystems (3.07%) and resources (0.38%). Bioethanol, xylonic acid, and lignin contributed differently at 22.59%, 12.5%, and 64.91%, respectively. Electricity generation was predominant in both scenarios, accounting for 99.05% of the environmental impact, primarily driven by its extensive usage in biomass handling and pretreatment processes. Sc-1 demonstrated a 13.05% lower environmental impact than Sc-2 due to decreased electricity consumption and increased bioethanol and xylonic acid outputs. This study highlights the pivotal role of pretreatment methods in wood-based biorefineries and underscores the urgency of sustainable alternatives like TsOH/pentanol. Additionally, adopting greener electricity generation, advanced technologies, and process optimization are crucial for reducing the environmental footprint of waste-based biorefineries while preserving valuable bioproduct production. [Display omitted] •Pinewood biorefinery producing bioethanol, xylonic acid, and lignin are environmentally analyzed.•LCA compares the environmental impacts of monophasic and biphasic pretreatment methods.•TsOH/pentanol pretreatment was environmentally superior to H2SO4 (13.05 % reduction).•Lignin production exhibited the highest environmental burden in both scenarios.•Electricity production was a hotspot in both scenarios, with a share of 99.05 %.