13 Dec, 2025

China-based research team reports low-temp, alkali-free hemp fibre pre-treatment that could cut energy use

Hempco Admin

3 Mins. Read

A new laboratory study suggests a two-step “light + enzyme” process can remove hemp’s stubborn natural gums at mild temperatures and neutral pH — potentially reducing energy demand and wastewater compared with conventional caustic treatments.

At a glance

The method pairs visible-light photocatalysis with a gentle pectinase enzyme wash to “degum” industrial hemp fibres.
Testing was run at ~30°C and neutral pH, aiming to protect cellulose structure (strength) while removing lignin and pectin (coarseness).
Researchers report ~74% lignin removal and ~71% pectin removal, plus an estimated 40–60% energy reduction versus common alkali processes (early-stage estimate).
Pilot-scale trials are still needed to confirm equipment requirements, reaction times and photocatalyst durability in continuous operation.

Why pre-treatment matters for hemp textiles

Hemp is a bast fibre: strong, breathable and naturally suited to lower-impact farming. But turning hemp stalks into soft, spinnable yarn is still one of the biggest bottlenecks for mainstream hemp textiles. That’s largely because hemp fibres are bound up with non-cellulosic “gums” — especially lignin and pectin — that make fibres coarse and difficult to separate.

Pre-treatment (sometimes called degumming) aims to break down or remove those gums before or during early processing, so mechanical separation can run more efficiently and produce cleaner fibre for textiles and higher-value composites.

What the researchers tested

In the new study, researchers linked to Qingdao University report a hybrid approach that combines two mild mechanisms:

Step 1: visible-light photocatalysis using a titanium dioxide / carbon quantum dot (TiO₂/CQDs) catalyst to help loosen and oxidise lignin-rich material.
Step 2: a pectinase enzyme wash to selectively break down pectin binders that hold fibre bundles together.

The key point: the process is designed to work at around 30°C and a neutral pH — avoiding the high heat and caustic alkali conditions commonly used in conventional pretreatment.

What they found

According to the paper’s abstract, the combined method achieved 73.75% lignin removal and 70.6% pectin removal, while maintaining cellulose crystallinity and overall fibre integrity — a balance that matters if you want softness and spinnability without sacrificing strength.

Microscopy and spectroscopy results reported in the study indicate that the “amorphous matrix” around the fibres was broken down, exposing cleaner fibre bundles that are more suitable for downstream refinement and spinning.

Energy and wastewater claims (with an important caveat)

The authors also provide preliminary energy-consumption estimates suggesting a 40–60% reduction compared with conventional alkali-based pretreatment. Because the method is alkali-free, it may also reduce the wastewater burden associated with caustic chemical processing — which can be particularly relevant for smaller or decentralised processing sites.

These figures are promising, but they’re not the same as a full commercial lifecycle assessment. The next step is pilot-scale work to validate throughput, reaction time, catalyst reuse, and equipment design under continuous operation.

What this could mean for hemp (and why we’re watching it)

If the approach scales, it could help tackle one of hemp’s long-running challenges: reliably producing fibre that’s clean and fine enough for higher-value textiles, without relying on high-energy, high-chemical processes.

For Australian hemp, cleaner pretreatment options could also support more localised processing models — especially if future systems can be run with simpler water treatment and lower energy inputs.