Concentration (process)

Elsevier, TrAC - Trends in Analytical Chemistry, Volume 113, April 2019
Microplastic (MP) studies in freshwater environments are gaining attention due to the huge quantities of plastic particles reported from lakes and rivers and the potential for negative impacts in these environments. Different units have been used to report MP densities, which makes it difficult to compare data and can result in reports of extremely high concentrations that do not reflect the original sample size. We recommended that the density of MPs from bulk samples be reported as number L −1 , while density from net samples should be reported as number m −3 .
The existing methods for recycling electronic wastes such as the printed circuit boards (PCB), which contains a large number of components and elements, face significant challenges when considering environmentally benign and easily separable disposal targets. We report here a low-temperature ball milling method that breaks down PCBs all the way into nanoscale particles which further enables enhanced separation of its different base constituent materials that are the polymer, oxide, and metal.