New Technologies for Safer Biogas Production and Ammonia Recovery

The search for alternatives to fossil fuels is no longer optional – it is a necessity. One solution that is gaining growing popularity is biogas plants, which, in theory, should serve as a model system: they manage bio-waste from agriculture and livestock, and produce ecological, green electricity and heat. Scientists are constantly working to improve their efficiency and expand the possible uses of biogas.

One such initiative, recognized by the National Centre for Research and Development, is the project titled “Porous Liquids for Ammonia Removal to Improve Biogas Production”, led by Dr. Min Ying Tsang, head of the Functional Macromolecules and Porous Materials Research Group at Łukasiewicz – PORT.

From Waste to Resource – Toward Sustainability

“I carried out an industrial postdoctoral project on the topic of biogas purification using porous liquids,” says Dr. Min Ying Tsang. Porous liquids were conceived in 2007 by Prof. Stuart James and first demonstrated in 2015. Since then, research into these materials has surged. One particular application is to purify biogas. “Taking further step, it is possible to apply this type of porous liquid to remove ammonia from biogas, thereby improving the biogas purification process and methane production – a widely used energy source. The recovered ammonia can be used as fertilizer in agriculture. We generate enormous amounts of waste – so why not turn it into something useful? That’s one of the core ideas behind biogas,” emphasizes Dr. Min Ying Tsang.

Porous Liquids Capture Ammonia from Biogas

Typical liquids do not have permanent pores – only empty spaces between molecules. Professor James dispersed porous solid particles in liquids in such a way that the molecules of the liquid did not block the pores in the particles, leading to the creation of a new class of materials: porous liquids. Today, researchers working on porous liquids are focused on developing mixtures of liquids and porous materials, such as metal-organic frameworks (MOFs), which – when combined with appropriate solvents – form stable suspensions.

“Porous materials like MOFs have been known for over 20 years and possess exceptional properties,” explains Dr. Tsang. “Imagine a few grams of material with surface area equal to that of a football field – that’s the kind of surface available for gas adsorption.”

This type of porous liquid is designed to capture ammonia from biogas, enhancing the safety and stability of its production. At the same time, the captured ammonia can be converted into fertilizer, creating a closed-loop system for agricultural resources. The goal of the project is to develop a stable porous liquid capable of efficiently capturing and releasing ammonia over extended periods. Dr. Min Ying Tsang hopes to collaborate with industry in a long run to test the technology.