Piperphentonamine Hydrochloride

Different marine sponge species from Tethys Bay, Antarctica, were analyzed for contamination by polyester and polyamide microplastics (MPs). The PISA (Polymer Identification and Specific Analysis) procedure was adopted as it provides, through depolymerization and HPLC analysis, highly sensitive mass-based quantitative data. The study focused on three analytes resulting from the hydrolytic depolymerization of polyesters and polyamides: terephthalic acid (TPA), 6-aminohexanoic acid (AHA), and 1-6-hexanediamine (HMDA). TPA is a comonomer found in the polyesters poly(ethylene terephthalate) (PET) and poly(butylene adipate co terephthalate) (PBAT), and in polyamides such as poly(1,4-p-phenylene terephthalamide) (Kevlar™ and Twaron™ fibers) and poly(hexamethylene terephthalamide) (nylon 6 T). AHA is the monomer of nylon 6. HMDA is a comonomer of the aliphatic nylon 6,6 (HMDA-co-adipic acid) and of semi-aromatic polyamides such as, again, nylon 6 T (HMDA-co-TPA). Except for the biodegradable PBAT, these polymers exhibit high to extreme mechanical, thermal and chemical resistance. Indeed, they are used as technofibers in protective clothing able to withstand extreme conditions as those typical of Antarctica. Of the two amine monomers, only HMDA was found above the limit of quantification, and only in specimens of Haliclona (Rhizoniera) scotti, at a concentration equivalent to 27 μg/kg of nylon 6,6 in the fresh sponge. Comparatively higher concentrations, corresponding to 2.5-4.1 mg/kg of either PBAT or PPTA, were calculated from the concentration of TPA detected in all sponge species. Unexpectedly, TPA did not originate from PET (the most common textile fiber) as it was detected in the acid hydrolysate, whereas the PISA procedure results in effective PET depolymerization only under alkaline conditions. The obtained results showed that sponges, by capturing and concentrating MPs from large volumes of filtered marine waters, may be considered as effective indicators of the level and type of pollution by MPs and provide early warnings of increasing levels of pollution even in remote areas.

Facile fabrication of the ultra-high-performance adsorbent can effectively ameliorate the Cr(VI)-pollution elimination in sewage control. Herein, a simple synthesis strategy is proposed to tap a versatile chelating resin poly(pyrogallol-tetraethylene pentamine) (PPTA) with respect to Cr(VI) removal from solution. Multiple changing factors which affect the adsorption behavior of PPTA are explored sequentially, such as initial pH, adsorbate concentration, adsorbent dosage, temperature, foreign ions, etc. The microstructure and functional mechanism of synthetic adsorbent are investigated systematically by means of various characterizations including TEM, EDS, FT-IR, XPS, etc. Consequently, the as-prepared PPTA-3 microsphere by reactant ratio of 1: 1 represents a brilliant synergistic adsorption and reduction result for Cr(VI) by the drastic electrostatic interaction of -NH₃⁺ and -OH₂⁺ groups, including satisfactory removal efficiency which closes to 100 % in low concentration, favorable specificity for the influence from coexistent ions (Mo(VI), Mn(VII), Cl^-, Cr(III), etc), and passable recyclability. Following the surpassingly fitting with Langmuir isotherm model, its maximum capacity reaches 714.29 mg g^-1 at 30 °C. The removal performance is essentially in agreement with the pseudo-second-order kinetics, simultaneously, suffers the rate-limiting impact depending on intra-particle diffusion process. In brief, this newly developed chelating resin presents an effective means with regard to the Cr(VI)-wastewater treatment or other uses in the future.