Plastics could be one of the most important environmental problems our society will face this century. The continuous and increasing production of these synthetic materials and the lack of an appropriate plastic waste management approach are intensifying the plastic contamination of water bodies worldwide, as well as land and air. The fact that plastics break down into smaller particles (micro-and nanoplastics) by the action of physical and chemical reactions and do not degrade biologically is a cause of concern as plastics are believed to cause harm in animals, plants, and humans. From sampling to identification, several techniques have been developed to determine the type of plastics found in aquatic environments. Following the sampling process of a water body, using nets, pumps, or other devices, depending on the sample type, it is usually necessary to treat the samples for separation and purification purposes. The next step is the use of analytical methods to identify the synthetic pollutants. The most common approaches are microscopy, spectroscopy, and thermal analysis. This Review summarizes the most important technologies applied to analyze the importance of plastics as a contaminant in water bodies, offering an excellent compendium regarding the sampling, separation, purification, and identification of micro-and nanoplastics in aqueous samples, including an overview of notable articles that have utilized these approaches successfully.

Although the world output of zirconium has been declining, increasing zirconium consumption cannot compete with this situation. For this reason, removal and recovery of zirconium become important. This work is focused on the removal of Zirconium (as ZrO22+) ions from an aqueous solution using polymer-enhanced ultrafiltration (PEUF) techniques with water-soluble Poly (sodium-p-styrene sulfonate, SSS) sorbent. The negatively charged sulfonic acid groups in the polymer interact with positively charged ZrO22+ cation thereby enabling the efficient removal of ZrO22+through ultrafiltration. The effect of polymer: zirconium mole ratio, initial solution pH, and the presence of interfering ions on the removal of zirconium was investigated. The obtained results demonstrated that ZrO22+ can be removed from the aqueous solution by the PEUF technique with more than 99% efficiency at pH ≥ 2 using polymer: Zr molar ratio of 5:1. The presence of interfering ions did not affect the percent removal of ZrO22+.

The consumption of ultrapure water (UPW) is continuously increasing owing to its numerous applications. In the production line of UPW using ion exchange resins, boron is usually found in the...

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A comparative study on Cu 2+ removal by shallow shell resin (Purolite SST 60) and traditional strongly acidic cation exchange resin (Purolite PFC 100) was performed. Batch experiments were carried out as a function of resin dosage, solution pH and contact time. Ion exchange reaction showed a pH dependent feature. Maximum removal of Cu 2+ achieved pH from 2 to 5. Sorption isothermal data is well interpreted by the Langmuir equation. Additionally, kinetic experiments showed that the pseudo first-order model was suitable for such resins. Thermodynamic parameters such as ∆G°, ∆S° and ∆H° of the ion exchange Cu 2+ on cation exchange resins were also calculated. The regeneration performance of shallow shell technology (SST) resin is better than PFC 100. A solution of 2M H2SO4 performed complete regeneration of SST 60 resin. On the other hand, maximum regeneration reached 80% for PFC 100 resin.