Quantum parameter analysis of the adsorption mechanism by freshly formed ferric hydroxide for synthetic dye and antibiotic wastewaters

Chemosphere ◽  
2021 ◽  
pp. 130577
Author(s):  
Yujia Tan ◽  
Zhiwen Cheng ◽  
Yawei Liu ◽  
Xiaoping Gao ◽  
Shiqiang Liu ◽  
...  
1989 ◽  
Vol 21 (4-5) ◽  
pp. 325-337 ◽  
Author(s):  
Cornelia Luedecke ◽  
Slawomir W. Hermanowicz ◽  
David Jenkins

A chemical model of ferric phosphate precipitation was developed describing ferric hydroxy-phosphate precipitation either alone or together with ferric hydroxide. Conditions for formation of one or two precipitates are examined. The model also incorporates an additional mechanism for phosphate removal through adsorption of PO43− ions on the precipitate. Experimental verification of the proposed model was carried out in lab-scale batch and continuous activated sludge units fed with municipal primary effluent and at five pH values in the range of 6.5 to 8.0. Solubility of ferric phosphate in the activated sludge system was significantly different from that reported in the literature for distilled water systems and was pH-dependent with a minimum at pH of approx. 7.0. It is proposed that the composition of precipitating ferric hydroxy-phosphate can be represented by the empirical formula Fe2.5PO4(OH)4.5. Corresponding solubility product was estimated at pKsp=96.7. The adsorption mechanism has an important effect on total phosphate removal, especially at low residual phosphate concentrations.


2018 ◽  
Vol 19 (3) ◽  
pp. 838-845
Author(s):  
Esra Bilgin Simsek ◽  
Pelin Demircivi ◽  
Ivan Novak ◽  
Dusan Berek ◽  
Ulker Beker

Abstract The competitive adsorption of antimonate and arsenate on carbon fibers decorated with ferric hydroxide (CF-Fe) has been investigated at different pH and temperatures. Tap and drinking water samples spiked with unitary and binary solutions were subjected to kinetic tests and compared with distilled water media. As the required time for attaining the arsenate concentration permitted by law, the legal limit was found as 3 hours for drinking and tap water systems. It was shown that arsenate can be adsorbed more strongly than antimonate. Such multiple adsorption/desorption cycles showed that the CF-Fe sample had approximately 96% of the first antimonate adsorption at the seventh cycle. X-ray photoelectron spectroscopy (XPS) analyses were performed in order to obtain insight into the adsorption mechanism.


Author(s):  
Valeriy G. Yakubenko ◽  
Anna L. Chultsova

Identification of water masses in areas with complex water dynamics is a complex task, which is usually solved by the method of expert assessments. In this paper, it is proposed to use a formal procedure based on the application of the method of optimal multiparametric analysis (OMP analysis). The data of field measurements obtained in the 68th cruise of the R/V “Academician Mstislav Keldysh” in the summer of 2017 in the Barents Sea on the distribution of temperature, salinity, oxygen, silicates, nitrogen, and phosphorus concentration are used as a data for research. A comparison of the results with data on the distribution of water masses in literature based on expert assessments (Oziel et al., 2017), allows us to conclude about their close structural similarity. Some differences are related to spatial and temporal shifts of measurements. This indicates the feasibility of using the OMP analysis technique in oceanological studies to obtain quantitative data on the spatial distribution of different water masses.


2015 ◽  
Vol 135 (6) ◽  
pp. 721-722 ◽  
Author(s):  
Wataru Kumagai ◽  
Kenichi Tamura ◽  
Junichi Tsuchiya ◽  
Keiichiro Yasuda

2020 ◽  
Vol 5 (1) ◽  
pp. 414
Author(s):  
Amsar Yunan

Maps or remote sensing can be interpreted as the process of reading using various sensors where data collected remotely can be analyzed to obtain information about the object, area or phenomenon. In this study, the author develops a flood disaster mapping information system applying overlays with scoring between the parameters. The determinant factors to provide flood hazard levels includes rainfall factors in the dasarian unit, land-use factors and land-use arbitrary factors. Of all these parameters, a scoring process will be carried out by assigning weights and values according to their respective classifications, then an overlay process will be performed using ArcGIS software. The author conducted this study in Nagan Raya Regency since this area experiences flooding annually.  Framing a thematic map of flood-prone areas in Nagan Raya Regency was designed using the flood hazard method. Spatial data that has been presented in the form of thematic maps as parameters are land use maps, landform maps, and dasarian rainfall maps (per 10 daily). The design of thematic maps that are prone to flooding is done by overlapping (overlay process). In contrast, the determination of the classification is done by adding scores to each parameter, with low, medium and high hazard levels. Parameter analysis shows the level of flood vulnerability in Nagan Raya Regency of each district, namely Beutong: high 0.21%, medium 13.68%, low 86.12%. Seunagan District: high 51.17%, medium 48.83%, low 0%. Seunagan Timur District: high 10.07%, medium 46.18%, low 43.75%. Kuala Subdistrict: high 29.66%, medium 68.99%, low 1.35%. Darul Makmur District: high 8.57%, medium 63.37%, low 28.06%. From the overall results of the study, it can be concluded that the danger of flooding in Nagan Raya Regency with a level of vulnerability: high 9.92%, moderate 42.65% and low 47.43%.


2013 ◽  
Vol 58 (1) ◽  
pp. 283-290 ◽  
Author(s):  
Y. Nishizaki ◽  
H. Miyamae ◽  
S. Ichikawa ◽  
K. Izumiya ◽  
T. Takano ◽  
...  

Our effort for decontamination of radioactive cesium scattered widely by nuclear accident in March 2011 in Fukushima, Japan has been described. Radioactive cesium scattered widely in Japan has been accumulating in arc or plasma molten-solidified ash in waste incinerating facilities up to 90,000 Bq/kg of the radioactive waste. Water rinsing of the ash resulted in dissolution of cesium ions together with high concentrations of potassium and sodium ions. Although potassium inhibits the adsorption of cesium on zeolite, we succeeded to precipitate cesium by in-situ formation of ferric ferrocyanide and iron rust in the radioactive filtrate after rinsing of the radioactive ash with water. Because the regulation of no preservation of any kind of cyanide substances, cesium was separated from the precipitate consisting of cesium-captured ferric ferrocyanide and ferric hydroxide in diluted NaOH solution and subsequent filtration gave rise to the potassium-free radioactive filtrate. Cesium was captured by zeolite from the potassium-free radioactive filtrate. The amount of this final radioactive waste of zeolite was significantly lower than that of the arc-molten-solidified ash.


2015 ◽  
Vol 32 (3) ◽  
pp. 231
Author(s):  
Haitao Liu ◽  
Minghai Wei ◽  
Kun Lin ◽  
Yiqing Xiao

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