A Systematic Review and Meta-Analysis of Hydrothermal Liquefaction of Lignocellulosic Biomass: Deciphering the Synergistic Effects of Feedstock Composition and Catalyst Selection on Bio-crude Yield and Quality

This record provides the complete systematic review package — manuscript, supplementary dataset, and PRISMA 2020 flow diagram — for a meta-analysis of hydrothermal liquefaction (HTL) of lignocellulosic biomass. The review synthesizes 103 data points extracted from 78 peer-reviewed experimental studies published between 2004 and 2026, following the PRISMA 2020 guidelines. METHODOLOGYDatabases searched: Scopus, Web of Science, ScienceDirect.Records identified: 2,495 (2,450 from databases + 45 from citation searching).After deduplication: 1,875. Excluded Round 1: 1,781.Full-text assessed: 94. Excluded Round 2: 16.Final studies included: 78 (103 data points).Quality assessment: 72 High / 6 Medium / 0 Low quality (6-criteria scoring). KEY FINDINGS- Mean bio-crude yield: 28.1 wt% (range 2.9–61.8 wt%)- Mean HHV: 28.8 MJ/kg- Optimal temperature: 251-300 °C (mean yield 28.5 wt%)- Optimal residence time: 16-30 min (mean yield 29.1 wt%)- Best catalysts vs no-catalyst baseline (22.9 wt%): MeOH co-solvent (+73%), K3PO4 (+69%), NaOH (+67%), K2CO3 (+56%), KOH (+53%)- Strongest cross-effect: alkaline catalyst × woody biomass CONTENTS1. Manuscript (Word document)2. Systematic review toolkit (Excel, 7 sheets: Dashboard, Screening, PRISMA Numbers, Data Extraction, Analysis, Quality Assessment, Writing Guide)3. PRISMA 2020 flow diagram (Word)4. README This work identifies major research gaps in feedstock × catalyst combinations and sets the experimental roadmap for the follow-up primary research (Paper 2).