Energy & Green Tech

Green adhesives made from whey

Every day, large quantities of whey are produced as a byproduct by the dairy industry. In Germany alone, this amounts to 12.6 million tons a year. For each kilogram of cheese, for example, 9 kilograms of whey are produced. ...

Energy & Green Tech

Hydrogen production and carbon capture in a single step

Hydrogen production takes place using natural gas as the raw material, combined with a very special ceramic membrane. Both hydrogen production and CO2 capture are achieved in a single step, which makes the method highly energy ...

Energy & Green Tech

Examining a new bio-inspired proton exchange membrane fuel cell

A team from the Department of Energy Engineering at the University of Seville has developed an experimental research focused on the design of a bio-inspired PEM fuel cell. The model they have obtained has reached a maximum ...

Energy & Green Tech

Capturing carbon with inspiration from battery chemistry

The need for negative emissions technologies to address our climate crisis has become increasingly clear. At the rate that our planet is emitting carbon dioxide—adding about 50 gigatons every year—we will have to remove ...

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Membrane

A membrane is a layer of material which serves as a selective barrier between two phases and remains impermeable to specific particles, molecules, or substances when exposed to the action of a driving force. Some components are allowed passage by the membrane into a permeate stream, whereas others are retained by it and accumulate in the retentate stream.

Membranes can be of various thickness, with homogeneous or heterogeneous structure. Membrane can also be classified according to their pore diameter. According to IUPAC, there are three different types of pore size classifications: microporous (dp < 2nm), mesoporous (2nm < dp < 50nm) and macroporous (dp > 50nm). Membranes can be neutral or charged, and particles transport can be active or passive. The latter can be facilitated by pressure, concentration, chemical or electrical gradients of the membrane process. Membranes can be generally classified into three groups: inorganic, polymeric or biological membranes. These three types of membranes differ significantly in their structure and functionality.

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