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Application of Ecotechnology in Ecosystem Management of Inland Waters
Published in Sven E. Jørgensen, Jose Galizia Tundisi, Takako Matsumura Tundisi, Handbook of Inland Aquatic Ecosystem Management, 2012
Sven E. Jørgensen, Jose Galizia Tundisi, Takako Matsumura Tundisi
Removal of superficial sediment can be used to support the recovery process of very eutrophic lakes and of areas contaminated by toxic substances (for instance, harbors). This method can only be applied with great care in small ecosystems due to the stirring up of suspended matter. Sediments have a high concentration of nutrients and many toxic substances, including trace metals. If a wastewater treatment scheme is initiated, the storage of nutrients and toxic substances in the sediment might prevent recovery of the ecosystem due to exchange processes between sediment and water. Anaerobic conditions might even accelerate these exchange processes; this is often observed for phosphorus, as iron(III) phosphate reacts with sulfide and forms iron(II)-sulfide by release of phosphate. The amount of pollutants stored in the sediment is often very significant, as it reflects the discharge of untreated wastewater for the period prior to the introduction of a treatment scheme. Thus, even though the retention time of the water is moderate, it might still take a very long time for the ecosystem to recover.
Properties of the Elements and Inorganic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
1356 Iron(II) oxalate dihydrate 1357 Iron(II) oxide 1372 Iron(II,III) oxide 1393 Iron(III) oxide 1322 Iron pentacarbonyl 1358 Iron(II) 2,4-pentanedioate 1394 Iron(III) 2,4-pentanedioate 1359 Iron(II) perchlorate 1395 Iron(III) perchlorate hexahydrate 1396 Iron(III) phosphate dihydrate
Phosphate loaded layered double hydroxides for active corrosion protection of carbon steel
Published in Corrosion Engineering, Science and Technology, 2022
Yongqiang Sui, Xuehui Liu, Shuangfeng Bai, Xiangbo Li, Zhiyong Sun
It is well known that phosphate-based corrosion inhibitive pigments are efficient inhibitors for corrosion protection of steel. Deshpande et al. prepared epoxy-based coating containing conducting polyaniline/nano-zinc phosphate composite pigment. Corrosion protection performance of the painted low-carbon steel samples lies in enhanced barrier protection, anodic protection and release of inhibiting phosphate ions when in contact with corrosive media [11]. Wang et al. investigated the synergetic effect of benzotriazole (BTA) and Na2HPO4 for inhibiting corrosion of carbon steel. Na2HPO4 inhibits the corrosion by forming iron phosphates in the presence of chloride ions [12]. Nam et al. developed a lanthanum diphenylphosphate compound for controlling the dominant cathodic process of the electrochemical reaction on the mild steel surface when exposed to aqueous chloride solution [13]. Poon et al. studied the corrosion inhibition of steel in seawater through a layer of rough iron (III) phosphate formed in water-saturated dodecane [14]. Recently, the phosphate-loaded LDHs into the coating matrix have been prepared and they provide efficient and active corrosion protection performance by releasing the inhibitors at corrosion sites. Alibakhshi et al. [15] synthesised Mg-Al-PO43− LDH nanoparticles through an anion exchange method. ICP measurements depicted the release of magnesium cation from LDH scaffold and phosphate anion from the galleries, which had great potency on the active corrosion protection on mild steel. Wang et al. [16] prepared sodium tripolyphosphate (STPP) pillared LDHs via the coprecipitation method, and the corrosion resistance of STPP-LDHs modified epoxy coating showed an improved anticorrosion performance compared to the neat epoxy coating.