HTL Biocrude Upgrading Technology Landscape 2026
HTL Biocrude Upgrading Technology Landscape
Hydrothermal liquefaction converts wet biomass into energy-dense biocrude at 250–374 °C and 10–25 MPa, bypassing costly drying steps. This report maps the patent and literature landscape across HTL biocrude production, catalytic upgrading, feedstock diversity, and emerging process integration through 2026.
From Wet Biomass to Drop-In Fuels: The HTL Biocrude Upgrading Landscape
HTL biocrude upgrading encompasses four interrelated technical domains: catalytic hydrotreating for heteroatom removal, co-solvent and solvothermal liquefaction to improve biocrude yield, biocrude separation and co-processing with fossil streams, and integrated process systems connecting HTL with downstream gasification, carbon capture, and hydrogen generation.
The core challenge documented across retrieved results is that raw HTL biocrude contains elevated nitrogen (from protein-rich feedstocks such as microalgae and sewage sludge), oxygen (from lignocellulosic feedstocks), and sulfur. Hydrodeoxygenation (HDO) and hydrodenitrogenation (HDN) under high hydrogen pressure remain the dominant upgrading pathways, documented across NiMo/Al₂O₃, Ru/C, Pt/C, and Ni-Ru/CeO₂ catalyst studies.
The dataset spans 2013–2026 and shows three developmental phases: a foundational phase (2013–2016) dominated by core process patents and early continuous-flow demonstrations; a development phase (2017–2021) broadening to diverse feedstocks and techno-economic analysis; and a scale-up phase (2022–2026) signaling a shift toward scalable systems and novel reactor architectures including downhole geothermal-style systems.
In this dataset, the US and WO (PCT) jurisdictions dominate foundational and process systems filings, while India is emerging as an active filing jurisdiction with academic (IIT Guwahati) and national oil company (Hindustan Petroleum) filings. Among retrieved records, Board of Regents University of Texas System and Universidad de Antioquia each represent 5 filings, making them the most prolific individual assignees in this dataset.
Assignee Filing Activity and Technology Cluster Distribution
Patent activity in this dataset is distributed across academic institutions, energy majors, national oil companies, and specialized startups. The following charts show top assignee filing volumes and technology cluster patent distribution as observed in retrieved records.
Top Patent Assignees by Filing Count (Dataset Snapshot)
In this dataset, Board of Regents University of Texas System and Universidad de Antioquia each account for 5 filings, making them the most prolific individual assignees among retrieved records.
↗ Click bars to explorePatent Filings by Technology Cluster — HTL Biocrude Upgrading (Dataset Snapshot)
In this dataset, catalytic hydrotreating (HDO/HDN) and integrated process systems account for the largest patent clusters, followed by co-solvent/solvothermal liquefaction and co-processing/refinery integration.
↗ Click bars to exploreKey Application Sectors for HTL Biocrude Upgrading Technology
HTL biocrude upgrading is being pursued across four principal application sectors: sustainable aviation fuel, marine fuels, road transport and engine testing, and waste valorization with biorefinery integration. Each sector draws on distinct feedstock streams and upgrading configurations documented in retrieved records.
Sustainable Aviation Fuel (SAF)
The EU Horizon 2020 HyFlexFuel project demonstrated HTL fuel chains from sewage sludge, straw, miscanthus, and microalgae to upgraded kerosene, with economic near-competitiveness for the sewage sludge pathway. Wet-waste HTL biocrude was evaluated for ASTM D7566 SAF compliance in Tier α/β testing. Studies reported 20.8–36.6% biojet fraction yield from upgraded HTL biocrude with significant emission reduction potential.
SAF / Aviation FuelMarine Fuels — Port of Rotterdam
A Dutch case study modeled sewage sludge HTL with centralized hydrotreating co-located at the Port of Rotterdam specifically for the marine fuels market. The model featured distributed HTL plants at wastewater treatment sites with centralized hydrotreating at refineries, published in 2022. This pathway was identified as a logistics-efficient route for marine biofuel production from urban wastewater infrastructure.
Marine BiofuelRoad Transport Engine Testing
HTL biofuel produced from municipal solid waste (MSW) was tested in optical compression ignition (CI) engines at blend levels of 5–40% with reference diesel, as reported by academic researchers in 2023. Microalgae biocrude was also assessed for marine diesel engine compatibility. Both upgraded and non-upgraded HTL biofuel blends were included in combustion and emissions characterization studies.
Road Transport FuelWaste Valorization and Biorefinery
University of Western Ontario filed active US patents (2019–2020) on co-processing wastewater sludge with lignocellulosic biomass for co-production of bio-gas and bio-oils. Integration of HTL with kraft pulp mills and ethanol biorefineries was analyzed for co-production economics by New Zealand researchers in 2020. Hindustan Petroleum Corporation Limited filed WO and AU patents in 2023 covering valuable chemicals from co-liquefaction of bioliquor and biomass.
Waste ValorizationKey Patent Assignees in HTL Biocrude Upgrading (Retrieved Records)
In this dataset, Board of Regents University of Texas System and Universidad de Antioquia each account for 5 filings, representing the highest individual filing counts among retrieved records. Innovation is distributed across academic institutions, energy majors, national oil companies, and specialized startups, with no single assignee holding more than 5 filings in retrieved records.
Top HTL Biocrude Assignees by Filing Count in Retrieved Records (Dataset Snapshot)
↗ Click bars to exploreBoard of Regents, Univ. Texas System
With 5 filings across US and EP jurisdictions (2015–2020) in this dataset, the University of Texas System represents the most prolific single academic assignee for foundational HTL-to-biocrude conversion systems. Patent family covers systems and methods for converting algal biomass to biocrude via hydrothermal liquefaction, with active and inactive US patents and one EP filing. Filings span from a 2015 foundational US patent through a 2020 continuation, documenting continuous-flow HTL process architecture.
United StatesUniversidad de Antioquia
Universidad de Antioquia has built the most geographically distributed recent patent family in this dataset, with 5 filings across US (active + pending), IN, EP, and AU jurisdictions filed in 2023–2024. Their solvothermal liquefaction process uses alcohol, ketone, and aldehyde solvent mixtures to achieve ≥30% biocrude yield with calorific value of 20–35 MJ/kg and less than 1% sulfur. This multi-jurisdiction filing strategy across five jurisdictions signals commercial intent for production-stage quality improvement distinct from post-HTL upgrading.
ColombiaNext-Generation HTL Biocrude Strategies: 2022–2026 Filing Signals
Filings dated 2022–2026 in this dataset signal a shift from laboratory fundamentals toward novel reactor architectures, distributed production networks, feedstock pre-activation, and global-scale solvothermal multi-solvent systems.
Downhole HTL: Repurposing Oil Well Infrastructure
Enoverra Energy & Environment’s 2024–2026 filing family (WO, AU, US) describes using existing oil and gas well casing, tubing, and electric heating elements to create underground HTL reaction zones. This approach eliminates the need for exotic surface-level high-pressure vessels and addresses the largest capital cost barrier in HTL commercialization. The US pending application dated 2026 is the most recent filing in the entire dataset.
Distributed-Centralized Production Networks
Circlia Nordic’s 2023 WO system patent describes multiple decentralized HTL units reporting to a central controlling facility, enabling modular deployment near waste sources while centralizing quality control and upgrading. A separate 2024 WO patent addresses viscosity reduction through alcohol-mediated processing above the boiling point of water. This distributed model aligns with the logistics structure modeled in the Port of Rotterdam marine fuels case study.
Catalytic Hydrotreating vs. Co-Solvent Solvothermal Liquefaction: Key Dimensions
Click any row to explore further.
| Dimension | Catalytic Hydrotreating (HDO/HDN) | Co-Solvent Solvothermal Liquefaction |
|---|---|---|
| Process Stage | Post-HTL upgrading of raw biocrude | Production-stage quality improvement during HTL |
| Key Catalysts | NiMo/Al₂O₃ (commercial benchmark), Ru/C, Pt/C, Ni-Ru/CeO₂ | No catalyst required; solvent acts as hydrogen donor |
| Operating Conditions | 300–400 °C; elevated H₂ pressure (~725 psi reported for Ru/C) | Subcritical water conditions with alcohol/ketone/aldehyde solvents |
| Biocrude Yield / Quality | Up to 92% denitrogenation (two-stage); ~97% oxygen reduction in co-distillation | ≥30% biocrude yield; calorific value 20–35 MJ/kg; <1% sulfur |
| Heteroatom Removal | Primary purpose: N, O, S removal via HDO and HDN | Reduces heteroatom content at production stage; lower N/O in raw biocrude |
| Key Assignees (Dataset) | Board of Regents Univ. Texas System, University of Western Ontario, academic researchers | Universidad de Antioquia (5 filings, 2023–2024 across 5 jurisdictions) |
| Feedstocks Documented | Microalgae, sewage sludge, Spirulina, lignocellulosics, pinewood | Spirulina (59.0% yield with formic acid), general biomass feedstocks |
| Commercialization Stage | Closest to commercial; benchmark in SAF and marine fuel studies | Active patent filing (2023–2024); commercial intent signaled by multi-jurisdiction strategy |
Frequently Asked Questions: HTL Biocrude Upgrading Technology
HTL converts wet biomass feedstocks into energy-dense biocrude under subcritical water conditions, typically at 250–374 °C and 10–25 MPa. Its key advantage over competing thermochemical routes such as pyrolysis is that it bypasses the costly drying steps required before processing, making it suitable for wet feedstocks like microalgae, sewage sludge, and food waste.
Raw HTL biocrude contains elevated levels of nitrogen (from protein-rich feedstocks such as microalgae and sewage sludge), oxygen (from lignocellulosic feedstocks), and sulfur. All three heteroatoms must be removed before biocrude qualifies as a drop-in fuel. Viscosity is an additional property target, addressed specifically by Circlia Nordic’s alcohol-mediated processing patent.
NiMo/Al₂O₃ catalysts operating at 300–400 °C are the commercial benchmark for HDO and HDN. Ru/C and Pt/C catalysts are reported at laboratory scale for enhanced denitrogenation. Ni-Ru/CeO₂ with H₂ was shown to achieve the highest higher heating value (HHV) and best elemental composition for algal biocrude upgrading at 450 °C. A two-stage approach — low-temperature stabilization followed by high-temperature HDN — is emerging for nitrogen-rich biocrudes, achieving up to 92% denitrogenation.
Studies documented in retrieved records report a 20.8–36.6% biojet fraction from upgraded HTL biocrude. The EU Horizon 2020 HyFlexFuel project demonstrated HTL fuel chains from sewage sludge, straw, miscanthus, and microalgae to upgraded kerosene with economic near-competitiveness for the sewage sludge pathway. Wet-waste HTL biocrude was evaluated for ASTM D7566 SAF compliance in Tier α/β testing.
Enoverra Energy & Environment’s 2024–2026 filing family (WO, AU, US) describes using existing oil and gas well infrastructure — casing, tubing, and electric heating elements — to create underground HTL reaction zones. This eliminates the need for exotic surface-level high-pressure vessels, addressing the largest capital cost barrier in HTL commercialization. The approach uses subsurface pressure and temperature to replace conventional high-pressure vessels.
In this dataset, the US leads with approximately 12 filings (active, pending, and inactive), followed by WO (PCT) with approximately 6, India (IN) and Australia (AU) with approximately 5 each, Europe (EP) with approximately 3, and Canada (CA) with approximately 3. India is emerging as an active filing jurisdiction, particularly from IIT institutions and national energy companies. No Chinese or Korean assignees appear in this patent subset.
Data and insights on this page are based on a limited patent and literature dataset and are for reference only. Figures may not represent the complete technology landscape.