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Modification of sodium lignosulfonate with reagent obtaining for drilling fluids
Published in Vladimir Litvinenko, Advances in Raw Material Industries for Sustainable Development Goals, 2020
R.A. Fedina, A.D. Badikova, I.N. Kulyashova, D.A. Dubovtsev, M.A. Tsadkin
Modification of the lignosulfonate feed was carried out as follows: iron (II) sulfate was introduced into the mass of technical lignosulfonate. The mass was maintained with constant stirring for 1.0-1.5 hours at a temperature of 30-40°C. Sodium dichromate was introduced into the resulting mass in the form of an aqueous 15-20% solution. The mass was maintained with constant stirring for 1 hour at a temperature of 30-40°C. Then, a modifying agent was introduced, in the form of an aqueous solution, and again kept for 1 hour under the same conditions. The finished liquid product was neutralized with caustic soda to pH=3.5-5.0. The finished mass was dried to a powder state, first at atmospheric pressure at a temperature of 65÷85°C, then in a vacuum oven to a constant weight (Kulyashova, 2016). The obtained experimental drilling reagents were analyzed according to the requirements of analytical control adopted in the production of reagents that regulate the quality of a drilling fluid (Badikova et al., 2014).
Basic studies for in-situ leaching project: Leaching of polished and powdered natural ore samples
Published in Vladimir Litvinenko, Innovation-Based Development of the Mineral Resources Sector: Challenges and Prospects, 2018
A. Korda, J. Heinrich, G. Heide
All samples were leached in Erlenmeyer flasks containing iron-ion (ferric and ferrous) sulfate solution adjusted to a pH of 1.6 with H2SO4 at room temperature (Fig. 4). The vessels were placed in an orbital shaker (100 rpm) for the duration of the experiment. For the preparation of the chemical leaching solution iron(III) sulfate was dissolved in deionized water (DI). In contrast, to make the biological leaching solution iron(II) sulfate heptahydrate was dissolved in the previously acidified DI. Before further use, both solutions were sterile filtered. The whole lab work was carried out under sterile conditions. An overview of all approaches of the two experimental series is given inTable 1. The differences of the leaching test series are briefly summarized.
World Water Crisis and Climate Change
Published in Stanley E. Manahan, Environmental Chemistry, 2022
Anhydrous iron(III) sulfate added to water forms iron(III) hydroxide in a reaction analogous to Reaction 7.1. An advantage of iron(III) sulfate is that it works over a wide pH range of approximately 4 to 11. Hydrated iron(II) sulfate, or copperas, FeSO4•7H2O , is also commonly used as a coagulant. It forms a gelatinous precipitate of hydrated iron(III) oxide; in order to function, it must be oxidized to iron(III) by dissolved oxygen in the water at a pH higher than 7.5, or by chlorine, which can oxidize iron(II) at lower pH values.
Spectroscopic studies of water-soluble superstructured iron(III) porphyrin. Interaction with the bovine serum albumin protein
Published in Journal of Coordination Chemistry, 2018
Hermas R. Jiménez, María Arbona
The “one-face” hindered sulfonated porphyrin, e-HSP(C12), was prepared as reported [45]. Anaerobic insertion of iron into the free base porphyrins was accomplished using iron(II) sulfate in water under reflux in the presence of sodium bicarbonate [45]. Bovine serum albumin (fraction V powder minimum 97% pure) was purchased from Sigma. All other reagents were analytical grade chemicals, purchased from Aldrich and Merck. Water was bidistilled before use. The concentrations of metalloporphyrin were measured spectrophotometrically using the extinction coefficient described previously (ε = 70.0 mM−1 cm−1 at 397 nm, pH 3, 25 °C) [45]. All the measurements were carried out with 0.1 M KNO3 as the background electrolyte under the same conditions in which the molar extinction coefficients of the metalloporphyrin has been determined. D2O (99.9%) was obtained from SDS Chemical. Sample concentrations for 1-D and 2-D 1H NMR were 3 to 6 mM of the metalloporphyrin dissolved in D2O or in 90% H2O/10% D2O.
Ultrasound-assisted adsorption on porous ceramic for removal of iron in water
Published in Environmental Technology, 2022
Luana Negris, Hélisson N. Santos, Rochele S. Picoloto, Felipe E. A. Alves, Erico M. M. Flores, Maria F. P. Santos, Maristela A. Vicente
In this study, broken pieces of porous ceramics that were discarded by local businesses were used. The ceramics were then fragmented into uniform 1 cm × 1 cm × 0.5 cm pieces. To determine the concentration of iron in aqueous solutions, the orto-phenantroline method [38] was used with the following reagents (analytical grade): hydroxyl ammonium hydrochloride, ammonium acetate, ammonium iron (II) sulfate hexahydrate, and 1, 10-phenanthroline monohydrate, which were purchased from Neon, São Paulo, Brazil; sulfuric acid (98%) and iron (II) sulfate heptahydrate salt, which were acquired from Dinâmica Co., São Paulo, Brazil; and glacial acetic acid (99.7%), which was purchased from Sigma-Aldrich, St. Louis, MO, USA.
Antibacterial properties of Cu-doped TiO2 prepared by chemical and heat treatment of Ti metal
Published in Journal of Asian Ceramic Societies, 2021
Kanae Suzuki, Taishi Yokoi, Misato Iwatsu, Maiko Furuya, Kotone Yokota, Takayuki Mokudai, Hiroyasu Kanetaka, Masakazu Kawashita
The amount of H2O2, which is a reactive oxygen species, was measured using H2O2 colorimetry. Two types of solutions were used for this purpose. Solution 1 was prepared by mixing 6 cm3 of 100 mol/m3 sulfuric acid and dissolving 11.8 mg of ammonium iron (II) sulfate hexahydrate into 30 cm3 of pure water. Solution 2 was prepared by dissolving 9.1 mg of xylenol orange tetrasodium salt and 2.186 g of sorbitol into 30 cm3 of pure water. A calibration curve was prepared using solutions 1 and 2, and 8.821 mol/dm3 of H2O2 solution.