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Friday, January 23, 2026

When scientists build nanoscale architecture to solve textile and pharmaceutical industry challenges

The study highlights a novel engineered crystalline membrane, whose one-nanometre gateways act as a high-precision sieve, enabling the recycling of polluted textile wastewater and improving the purity and cost-efficiency of generic medicines.

Indian Institute of Technology Gandhinagar

Artist’s impression of the precise molecular transport facilitated by POMbranes — image:
Ultra-precise “POMbranes” sieve out larger molecules (red) while allowing only 1-nanometer-sized species (green) to pass through its pores, enabling sharp molecular sorting.
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Credit: The graphic has been created by Central Salt and Marine Chemical Research Institute, Gujarat, India.

Scientists from the CSIR-Central Salt and Marine Chemicals Research Institute (CSMCRI), Indian Institute of Technology Gandhinagar, the Nanyang Technological University, Singapore, and the S N Bose National Centre for Basic Sciences have collaborated to develop a new class of highly precise filtration membranes. The research, published in the Journal of the American Chemical Society, could significantly reduce energy consumption and enable large-scale water reuse in industry.

Everyday industrial processes, like purifying medicines, cleaning textile dyes, and processing food, rely on “separations.” Currently, these processes are incredibly energy-hungry, accounting for nearly 40% to 50% of all global industrial energy use. Most factories still use old-fashioned methods like distillation and evaporation to separate ingredients, which are expensive and leave a heavy carbon footprint. Although membrane-based technologies are considered cleaner, most polymer membranes currently used in industry have irregularly sized pores that tend to degrade over time, limiting their effectiveness. Thus, they lack the precision and long-term stability needed for demanding industrial applications.

“To address these limitations, we engineered a new class of ultra-selective, crystalline membranes called “POMbranes”, which contain pores that are about one nanometre wide, thousands of times thinner than a human hair,” said Dr Shilpi Kushwaha, Senior Scientist at CSMCRI. This precise pore size results from an intricate molecular design that mimics the action of biological gatekeepers like aquaporins, which use pores of precisely the right size to filter molecules. The team utilised polyoxometalate (POM) clusters, which feature a permanent, naturally occurring hole exactly 1 nanometer wide. According to Ms Priyanka Dobariya, a CSMCRI research scholar and co-first author of the article, “These POMs are tiny, crown-shaped metal clusters that have a permanent, perfect hole in their centre that does not change or lose shape, which is the biggest hurdle with traditional plastic filters.”

To arrange billions of such rings into a continuous, defect-free sheet suitable for use as a membrane, the research team attached flexible chemical chains to the clusters. When placed on water, the clusters naturally spread out and align, forming an ultrathin film over large areas. By adjusting the length of the attached chains, the team could control how tightly the clusters packed together. “This forced molecules to cross the membrane through the only open path, the one-nanometre holes built into each cluster, allowing the membrane to act like a high-tech sieve,” added Dr Raghavan Ranganathan, Associate Professor at IITGN’s Department of Materials Engineering. He and Mr Vinay Thakur, a PhD scholar at IITGN and the co-first author of the article, performed molecular-level simulations that helped explain how the membranes work.

The research team has tested the membrane to distinguish between molecules that differ by just 100-200 Daltons. Such precision is extremely difficult to achieve with conventional polymer membranes. According to Dr Ketan Patel, Principal Scientist at CSMCRI, this level of control opens new possibilities for sustainable manufacturing. “Our membranes show almost ten times better separation performance compared to existing technologies, while remaining flexible, stable, and scalable,” he said. “Additionally, these membranes are flexible, stable across different acidity levels (pH ranges), and can be manufactured in large sheets. This combination is essential if the membranes are to be adopted widely in industry.”

The technology is highly relevant to India’s textile and pharmaceutical sectors, both critical pillars of the economy. The textile and apparel sector contributes over 2.3% of GDP. It accounts for around 13% of industrial production, with the domestic market valued at USD 160-225 billion and projected to grow to USD 250-350 billion by 2030. However, textile dyeing and finishing generate large volumes of polluted wastewater, making dye removal and water recycling persistent challenges. The new membranes could selectively remove dye molecules while allowing water to be reused, reducing freshwater consumption and chemical discharge. This is particularly significant as India’s wastewater treatment market is expected to grow rapidly in the coming years.

For the pharmaceutical sector, where precise separations are essential for drug purity and cost-effective manufacturing, the technology could offer significant benefits. “Processes like drug purification and solvent recovery are both energy-intensive and quality-sensitive,” noted Mr Vinay Thakur. “Highly selective membranes such as these can lower energy use while maintaining the stringent standards required in pharmaceutical production.”

The versatility of the engineered POMbranes makes them an efficient platform technology. Their tunable structure, high selectivity, and stability under harsh chemical conditions ensure their suitability for a wide range of separation challenges, from wastewater treatment to advanced chemical processing. As industries seek solutions that balance efficiency, durability, and sustainability, molecularly engineered membranes could form the backbone of next-generation manufacturing technologies. By drawing on a core principle from biology—precise control at the molecular scale—and translating it into a scalable materials system, the research shows how nature-inspired design can address real industrial needs.

Journal

Journal of the American Chemical Society

DOI

10.1021/jacs.5c17644

Article Title

Large-Area Supramolecular Crystalline Thin Films of Polyoxometalates with Controlled 1-nm Pores Enabling Ultra-Selective Molecular Transport

Article Publication Date

13-Jan-2026

Engineering a low-cost alternative catalyst for producing sustainable petrochemicals

Newly identified methods to harness the properties of tungsten carbide could yield viable substitutes for precious metals like platinum.

University of Rochester

Slip of the tungsten — image:
The evolution of carburization (depicted by the spheres) under kinetic control (illustrated by the surface contours). The molecular beams represent gas evolution under synthesis conditions while the fiery sphere highlights the formation of the pure tungsten semi-carbide phase with additional molecular beams at the top to illustrate its catalytic performance.
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Credit: Illustration by Sinhara M. H. D. Perera

Important everyday products—from plastics to detergents—are made through chemical reactions that mostly use precious metals such as platinum as catalysts. Scientists have been searching for more sustainable, low-cost substitutes for years, and tungsten carbide—an Earth-abundant metal used commonly for industrial machinery, cutting tools, and chisels—is a promising candidate.

But tungsten carbide has properties that have limited its applications. Marc Porosoff, an associate professor in the University of Rochester’s Department of Chemical and Sustainability Engineering, and his collaborators recently achieved several key advancements to make tungsten carbide a more viable alternative to platinum in chemical reactions.

The best turn of phase

Sinhara Perera, a chemical engineering PhD student in Porosoff’s lab, says that part of what makes tungsten carbide a difficult catalyst for producing valuable products is that its atoms can be arranged in many different configurations—known as phases.

“There’s been no clear understanding of the surface structure of tungsten carbide because it’s really difficult to measure the catalytic surface inside the chambers where these chemical reactions take place,” says Perera.

In a study published in ACS Catalysis, Porosoff, Perera, and chemical engineering undergraduate student Eva Ciuffetelli ’27 overcame this problem by very carefully manipulating tungsten carbide particles at the nanoscale level within the chemical reactor—a vessel where temperatures can reach above 700 degrees Celsius. Using a process called temperature-programmed carburization, they created tungsten carbide catalysts in their desired phase inside the reactor, ran the reaction, and then studied which versions performed the best.

“Some of the phases are more thermodynamically stable, so that’s where the catalyst inherently wants to end up,” says Porosoff. “But other phases that are less thermodynamically stable are more effective as catalysts.”

The researchers identified one particular phase—β-W₂C—that works especially well for a reaction that turns carbon dioxide into important precursors for making useful chemicals and fuels. With further fine-tuning by industry, Porosoff and his team think this phase of tungsten carbide could be as effective as platinum without the drawbacks of high cost and limited supply.

Plastic upcycling

Porosoff and his colleagues have also explored tungsten carbide as a catalyst for upcycling plastic waste and converting old plastics into high-quality new products. A study in the Journal of the American Chemical Society, led by Linxao Chen from the University of North Texas, and supported by Porosoff and URochester Assistant Professor Siddharth Deshpande, showed how tungsten carbide can be used for a process called hydrocracking.

Not only was tungsten carbide less costly than platinum catalysts for hydrocracking, it was also more than 10 times as efficient.

Hydrocracking involves taking big molecules such as polypropylene—the basis of water bottles and many other forms of plastic—and chemically breaking them down into smaller molecules that can be used for new products. While hydrocracking has been used in oil and gas refining, applying it to process plastic waste has been a problem because of the high stability of polymer chains that make up most single-use plastics, and presence of contaminants that deactivate the catalysts. The precious metals, such as platinum, that are currently used as catalysts deactivate rapidly and are supported within microporous surfaces that do not have room for the long polymer chains in single-use plastics.

“Tungsten carbide, when made with the correct phase, has metallic and acidic properties that are good for breaking down the carbon chains in these polymers,” says Porosoff. “These big bulky polymer chains can interact with the tungsten carbide much easier because they don’t have micropores that cause limitations with typical platinum-based catalysts.”

The study showed that not only was tungsten carbide less costly than platinum catalysts for hydrocracking, it was more than 10 times as efficient. The researchers say this opens exciting new avenues for improving catalysts and turning plastic waste into new materials, supporting a circular economy.

Taking the temperature

Underpinning these advancements in creating more efficient catalysts is the ability to accurately measure temperatures on the catalyst surfaces. Chemical reactions can either absorb heat (endothermic) or release heat (exothermic), and controlling the catalyst surface temperature allows scientists to efficiently coordinate multiple reactions. But the measurements currently used to take the temperature of catalysts provide rough averages that do not give enough nuance to accurately measure the precise conditions needed to effectively study chemical reactions.

Using optical measurement techniques developed in the lab of Andrea Pickel, a visiting professor in the Department of Mechanical Engineering, the researchers devised a new way to measure temperature within chemical reactors. They described the new technique in a study published in EES Catalysis.

“We learned from this study that depending on the type of chemistry, the temperature measured with these bulk readings can be off by 10 to 100 degrees Celsius,” says Porosoff. “That’s a really significant difference in catalytic studies where you’re trying to ensure that measurements are reproducible and that multiple reactions can be coupled.”

The team applied their new technique to study tandem catalysts, where an exothermic reaction provides enough heat to trigger an endothermic one. Effectively pairing these reactions can minimize waste heat and lead to more efficient chemical engineering processes.

Porosoff says the technique could also help change the way researchers conduct catalysis studies, leading to more careful measurements, reproducible work, and more robust findings across the field.

The ACS Catalysis study was funded with support from the Sloan Foundation and the Department of Energy; the Journal of the American Chemical Society study was funded with support from the National Science Foundation; the EES Catalysis study was funded with support from the New York State Energy Research and Development Authority via the Carbontech Development Initiative.

Heat is transferred from a particle undergoing an exothermic reaction (red) to a particle undergoing an endothermic reaction (blue). A thermal probe excites a particle with infrared light, and the particle emits green light, providing a more accurate form of temperature measurement for the surfaces of catalysts than researchers were previously able to achieve.

Credit

Illustration by Sinhara M. H. D. Perera