SepPure nanofilters significantly reduce the energy costs of industrial separation processes

SepPure nanofilters significantly reduce the energy costs of industrial separation processes

As pressure mounts on companies to reduce their dependence on oil and gas, established processes are being challenged even on an industrial scale, giving technology a chance to intervene. Seppuro is seeking to replace the complex distillation of gas-based oils with a nanometer-scale membrane, and its approach has attracted $12 million in a new round of funding.

All types of oils must be extracted and purified from their source, which can be a seed, fiber or other organic material. Sure, you can crush an olive and get a lot of oil out of it, but not all of it; To do this, the pulp is immersed in a large amount of solvent, such as acetone or hexane, which extracts the remaining oil. The resulting mixture is then heated, usually with natural gas or oil, and the solvent and oil are separated.

This fuel-intensive process has been around for decades, in part because the high temperatures required make it impossible to use solar or wind energy as a heat source.

A possible alternative emerged many years ago in the field of water purification, where a distillation process was also used for a long time to separate H2O from impurities. Membranes can be designed to allow certain substances to pass while blocking others, leaving water molecules behind, for example, but not large organic molecules. This approach has caught on in the water industry because it is cheaper, simpler, and uses less energy (look for “reverse osmosis” on the label).

SepPure founder and CEO Mohammad Farahani explained that the pressures of climate change and gas prices (not to mention cost cutting) have led others to consider membranes as an option. For example, Divisas has developed a membrane that separates hydrogen from carbon dioxide and Membrion has developed a membrane to remove heavy metals from water. But water is not a particularly hard substance, unlike many chemical precursors to beneficial oils and other molecules.

“It took a long time to find a good solution for water, and basically all the companies making membranes were focused on water,” Farahani said. “Perhaps people only started looking at chemical resistant membranes 10 years ago. We believe we are in the same place we were 40 years ago when water membranes were introduced; in fact, they are being introduced everywhere.”

A computer shows a cross-section of SepPure nanofilter tubes.

SepPure produces what they call a hollow fiber nanofilter, which is exactly what it sounds like: a hollow polymer fiber with a surface designed on a nanometer scale that allows only certain molecules to pass through. Pack a few and put them in a tube and squeeze the liquid through the tube to filter it. Although the membrane does not separate the two substances 100%, it significantly reduces the scope of the distillation step. The concept is not new and is actually used all over the membrane industry, but what sets SepPure apart is its durability and compactness.

“Strong solvents can easily dissolve polymers – you have to make polymeric membranes with solvents, but they have to be resistant to solvents. That is a challenge and a lot of research has been done to get there,” says Farahani. “The beauty of what we’ve been doing is making fibers that can withstand harsh chemicals, high temperatures and high pressures.”

Water and gas aren’t as picky in those categories, which is why they’ve attracted the most attention, but now there’s a version that can separate oils from solvents or other valuable molecules from an equally difficult mixture. This is used in all industries that still use distillation due to the fragility of the old membrane processes, and there are many. Separation processes are responsible for a significant portion of global energy consumption and emissions.

SepPure has a competitor in the German Evonik, which makes a similar product. But Farahani said that while this older version of the technique is good for high-margin products like pharmaceuticals, it’s too slow and bulky to be used in high-volume, low-margin processes like cooking oil production.

Hollow fiber nanotubes are made in the lab and a small version of the final filter is shown.

Filters usually come in a standard size: a 4-inch diameter, 40-inch long tube. SepPure claims it can fit five times as much membrane in that space, improving efficiency and reducing costs – pushing five times as much material through the same number of tubes or filtering the same amount in much less space. And this is without taking into account the increase in pressure and other combinatorial factors.

All in all, Farahani estimates that through these gains and the reduction in fuel-based heating, they reduce the cost of producing (say) 100,000 tons of oil in a year from about $7.5 million to about $7.5 million. $2.5 million. And if the filter fibers are used after a number of years, they can apparently be reused to make flame retardant substances.

The $12 million A round was led by SOSV, with participation from Anji Microelectronics, Real Tech Fund, Seeds Capital, EPS Ventures and others. The company raised $2.5 million in 2019.

The money will be used to complete the construction of Singapore’s first filter plant.

“Once we start deploying our technology solutions to customers, we will quickly reach full capacity. Anticipating the growing demand for our modules, our team is already working on expansion plans,” said Farahadi.

Source: La Neta Neta