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List of Chemical Substances
Published in T.S.S. Dikshith, and Safety, 2016
In 1808, Sir Humphry Davy and J. L. Gay-Lussac discovered boron. It is a trivalent, non-metallic element that occurs abundantly in the evaporite ores, borax and ulexite. Boron is never found as a free element on Earth. Boron as a crystalline is a very hard, black material with a high melting point, and exists in many polymorphs. Boron has several forms, the most common form being amorphous boron, a dark powder, non-reactive to oxygen, water, acids, and alkalis. It reacts with metals to form borides. Boron is an essential plant micronutrient. Sodium borate is used in biochemical and chemical laboratories to make buffers. Boric acid is produced mainly from borate minerals by the reaction with sulfuric acid. Boric acid is an important compound used in textile products.
Recent Advances in Boron-Based Flame Retardants
Published in Yuan Hu, Xin Wang, Flame Retardant Polymeric Materials, 2019
Due to their low dehydration temperature and water solubility, sodium borates (except the anhydrous sodium borate) are normally only used as flame retardants in cellulose insulation, wood timber, textiles, urethane foam, and coatings. Thus, in cellulosic material and wood products, it is commonly used in combination with boric acid, which is an effective smoldering inhibitor. In addition, a combination of boric acid and sodium borate can also result in significantly higher water solubility.
An overview of the mineralogical characterization and treatment strategies of Bauxite residues for their sustainable management
Published in Mineral Processing and Extractive Metallurgy Review, 2023
Adèle Dramou, Lev O. Filippov, Ndue Kanari, Eric Allain, Sekou Traoré, Inna V. Filippova
(Chun et al. 2017) made significant progress in iron recovery through alkaline roasting at optimal temperature and residence time of 1300°C and 30 minutes respectively using a sodium salt. Sodium borate (Na2B4O7.10H2O) was used as an additive to improve iron recovery by wet magnetic separation, obtaining 90.05% conversion at the optimal 4% addition. This indicates that, sodium borate has a significant effect on the reduction and magnetic separation. Sodium salts, such as sodium sulfate, sodium carbonate, or other additives, especially magnesium carbonate is also observed to facilitate the growth of metallic iron particles while improving the efficiency of magnetic separation. Therefore, in the absence of the sodium salts, the metallic iron particles remain fine and dispersed.
Study on combustion of aluminum powder mixed with sodium borohydride at low starting temperature in steam atmosphere
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Wei Shi, Weijuan Yang, Longjin Du, Jianzhong Liu, Junhu Zhou
Sodium borohydride is a kind of coordination hydride with a pretty high content of hydrogen. Therefore, it has got much attention in the field of fuel cells (Nunes et al. 2016). Its hydrogen production technology by hydrolyzed is considered to be safe and efficient (Liu and Li 2009; Muir and Yao 2011). According to the empirical formula of sodium borohydride half-life proposed by Kreevoy in 1979 (Kreevoy and Jacobson 1979), (, t1/2/min, T/K), its decomposition rate is mainly related to temperature and pH of the solution. Under the condition of 25°C and pH of 14, the half-life of sodium borohydride is about 430 days. A common way to promote the hydrolysis of sodium borohydride is to add catalysts (Netskina et al. 2018; Saka et al. 2015). Hydrogen and water-soluble sodium borate are produced by hydrolysis of sodium borohydride, as the following chemical equation shows:
Evaluation of three different glassy composites (quinary matrix designed using Cr2O3/Na2O/MnO2) in respect of radiation shielding behaviors
Published in Radiation Effects and Defects in Solids, 2021
Ozan Toker, Bayram Bilmez, Melis Ö. Toker, H. Birtan Kavanoz, Özgür Akçalı, Mehmet Yılmaz, Orhan İçelli
Sodium oxide (Na2O) is used to amplify the glass formation regions of other materials and helps to sustain more ion exchange and makes it easier to produce low melting glass. Sodium borate glasses have found public interest in the last decade and are used in many diverse areas from radiation shielding to fiberglass production (16,17).