Mesoporous materials from polysaccharides
Dr Rob McElroy , CTO , and Susan Brench , CEO , at Starbons , highlight the use of their eponymous material in separations
Figure 1 – Examples of compounds isolated using Starbon SPE
Starbon * materials , or Starbons , are very versatile materials , with tuneable surface chemistry and porosity . There are over 50 peer-reviewed publications relating to them in a range of end use applications . For some applications , there are no existing alternative technologies . For others , they offer a sustainable , reusable and environmentally benign alternative to existing systems , while also delivering a step change in performance . A Starbon material is like a solid sponge . The hole sizes and ‘ stickiness ’ of the ‘ sponge ’ allow different sized species to pass through or stick to the Starbon . Varying the stickiness means that substances can be captured in many ways , so the company can design technical solutions tailored to the customer ' s specific needs and end use application . Market application examples include API isolation , gas capture ( including CO 2
), gas monitoring equipment and precious metal recovery . Principally , Starbons are derived from one of three materials : starch ( from potato waste , corn starch etc ), alginic acid ( from kelp or other sea weed ) or pectin ( from fruit waste , principally citrus peel ). However , any
polysaccharide that can be gelled is a viable feedstock .
Starbon applications
Starbon materials have shown application in a range of fields , although these can be condensed into four main headings : capture , catalysis , energy and separations . Capture has been shown for metals ( including gold , platinum and palladium from aqueous acidic streams via reduction and deposition onto the surface of the Starbon ); and gases ( switchable capture for inert gases like
CO 2 and permanent capture for toxic gases such as H 2
S ). Heterogeneous catalysis has been achieved through the change or introduction of functional groups ( acid or base ) on the surface of the Starbon .
Starbons have also been used as active supports in capturing single metals as nanoparticles , for instance palladiummediated coupling reactions , or in immobilising enzymes . In energy applications , Starbons have been applied to lithium-ion battery technology , both in anode and cathode electrode manufacture , as well as being combined with graphene in the production of capacitors . It is in separations where the most recent and exciting applications have arisen ( Figure 1 ). The tuneability of the starting material , surface chemistry and pore size mean that Starbon materials can be produced to capture compounds of interest selectively from complex mixtures . This is done through a simple and fast solid phase extraction ( SPE )
Figure 2 – HPLC of adsorption and desorption systems using a natural product extract Source : J . Attard , Starbon materials for a circular economy , PhD thesis , University of York , 2018
56 SPECIALITY CHEMICALS MAGAZINE ESTABLISHED 1981