I D
× COMMENTARYCOVER STORYIN THE NEWSNEWSFRONTSCHEMENTATOR + Show More
Chemical Engineering MagazineChementator Briefs
Sulfur control Preferential Oxidation Catalysis — a new catalytic solution…
BUSINESS NEWS
Chemical Engineering MagazineBusiness News
Plant Watch Perstorp will construct new plant for sodium formate…
TECHNICAL & PRACTICALFEATURE REPORTFACTS AT YOUR FINGERTIPSTECHNOLOGY PROFILEEQUIPMENT & SERVICESFOCUSNEW PRODUCTS + Show More SHOW PREVIEWS

Comment

Highly selective rare-earth separation using bacteria filters

By Mary Page Bailey |

Mixtures of rare-earth metals (REMs) are notoriously difficult to separate, but a team of researchers from Harvard University (Cambridge, Ma.; www.seas.harvard.edu) has developed a method for efficiently extracting REMs with a high level of selectivity. By taking advantage of the complex surface chemistry of bacteria-coated filters, the team discovered that it could essentially tailor the filter to control the bio-absorption of certain REMs while allowing others to pass through the filter for extraction. The key to this selectivity is the affinity of the bacteria’s surface groups for bioabsorbing different REMs. By passing various low-pH solutions through the filter prior to any REMs — a step the team calls “pre-protonation” — certain surface groups become occupied with protons, and the REMs for which these occupied groups have affinity will pass through the filter (see diagram). The team found that pre-protonation with subsequently lower-pH solutions resulted in the extraction of heavier REMs. By fine-tuning the pre-protonation step, the filter can differentiate between extremely similar REMs, even among neighboring lanthanides. The REMs are recovered from the filtrate using traditional extractive metallurgy techniques. The…
Related Content

Chemical Engineering publishes FREE eletters that bring our original content to our readers in an easily accessible email format about once a week.
Subscribe Now
Quadruple Sensor Lifetime with a Retractable Housing
Minimizing Explosion Risk Where Other Solutions Cannot
Minimizing Corrosion with Fast, Robust Gas Analysis
Lower Measurement Point Costs with Automatic pH Sensor Cleaning
Reduce the Risk of Corrosion in Fertilizer Production

View More

Live chat by BoldChat