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CARIX Process—A Novel Approach to Desalination by Ion Exchange
Published in Arup K. Sengupta, Ion Exchange Technology, 2021
Processes of the first type make use of the formation of thermally unstable salts during the service cycle. By subsequently passing the liquid phase through a cation exchanger in the ammonium form and an anion exchanger in the carbonate form, dissolved salts are replaced by (NH4)2CO3, which decomposes into ammonia and carbon dioxide at elevated temperatures. After exhaustion, the resins are regenerated by a solution of ammonium carbonate, which is generated from ammonia and carbon dioxide. The process that uses strong electrolyte resins was applied in the sugar industry but not in the demineralization of drinking water [20].
Role of Nanotechnology: Emerging Path from Soil to Fork
Published in Megh R. Goyal, Santosh K. Mishra, Lohith Kumar Dasarahalli-Huligowda, Nanotechnology Applications in Agricultural and Bioprocess Engineering, 2021
Lohith Kumar Dasarahalli-Huligowda, Gajanan Gundewadi, Vijay S. Rakesh Reddy
Nanomaterials are also being used to develop environmentally friendly fertilizers to lower greenhouse gas emissions during crop production. Widely used carbon-based fertilizers like ammonium bicarbonate and urea in different soil types despite their efficiency are susceptible to decomposition and hydrolysis leading to elevated levels of byproducts such as nitrogen, ammonium carbonate and ammonia in soils. Further decomposition results in the accumulation of nitrate levels in soils leading to toxic effects and environmental damage. One such invention aims to reduce greenhouse gas emission whilst increasing fertilizer efficiency by reducing the decomposition of carbon containing fertilizers by incorporating carbon-nano constituents, nano-graphite, and carbon-colossal [11].
Traffic Pollution: Perspective Overview toward Carbon Dioxide Capture and Separation Method
Published in Maniruzzaman A. Aziz, Khairul Anuar Kassim, Wan Azelee Wan Abu Bakar, Aminaton Marto, Syed Anuar Faua’ad Syed Muhammad, Fossil Free Fuels, 2019
Maniruzzaman A. Aziz, Khairul Anuar Kassim, Wan Azelee Wan Abu Bakar, Fauzan Mohd Jakarmi, A. B. M. Amimul Ahsan, Salmiah Jamal Mat Rosid, Susilawati Toemen
In the sieve adsorption process, molecules are separated on the basis of their mass or size. This method is suitable for different forms of CO2 capture [161]. A number of studies were done to improve adsorption of CO2 through chemical modification using a surficial molecular sieve. Adsorption is carried out on large inorganic surface interacting with organic compounds. Interactions among the basic surface and the acidic molecule of CO2 under water-free conditions produce ammonium carbamates. If the reaction takes place in the presence of water, ammonium bicarbonate and ammonium carbonate are formed [174]. Comparable to the ammonia absorption process without water, the ability to absorb CO2 is preferable with a molecular weight of 0.5 mol CO2/mol, whereas 1.0 mol CO2/mol is preferable in the existence of water. Mesoporous molecules such as silica [174,175], SBA-1 [176], SBA-15 [177], MCM-41 [176,178,179] and MCM-48 [167] are better because their pores are wide and easy to reach by the amino group.
Aqueous stability relations in the hydrometallurgical processing of cerium bastnasite
Published in Mineral Processing and Extractive Metallurgy, 2022
Isehaq Al-Nafai, K. Osseo-Asare
After the solution purification, there is a number of well-known methods for cerium extraction such as solvent extraction, ion exchange and precipitation. Solvent extraction of cerium is the most effective method. Usually, cerium is separated by solvent extraction as Ce(IV) due to its high separation efficiency with other RE(III). The tetravalent cerium ion () is the most stable tetravalent ion of rare earths in aqueous media and it can form stable complexes with fluoride, nitrate, bisulphate and dihydrogen phosphate ions in solution. These complexes can then be easily extracted by organic extractants. Organic extractants include acidic and neutral organophosphorus, bifunctional ionic liquid, amines and others. After extraction of Ce into the organic phase, the pure Ce solution can be collected by stripping. Then, Ce products can be recovered by the addition of ammonium carbonate, oxalic acid or ammonia water. Finally, calcination converts Ce products to high purity Ce oxide (Habashi 1997; Basualto et al. 2013; Gupta and Krishnamurthy 2015; Li et al. 2019).
Ammoniacal leaching process for the selective recovery of value metals from waste lithium-ion batteries
Published in Environmental Technology, 2023
Xiaofen Liu, Kui Huang, Hao Xiong, Haili Dong
Most of the recyclable value in the spent LIBs lies in the cathode [3]. Based on the composition of the cathode, LIBs can be classified as LiCoO2, LiNixMnyCozO2, LiFePO4 and LiMn2O4. The current recycling method developed for spent LIB is very specific, even if the battery type is the same but the composition is different [27]. In this study, an ammoniacal leaching recovery process was investigated to extract Co/Ni/Li metals from a mixed types of waste cathode materials (hybrid powders of LiCoO2, LiNixMnyCozO2 and LiMn2O4). Ammonium sulphite is used as the reductant in the leaching process to accelerate the leaching of the valuable metals in the cathode of spent LIBs. Ammonia and ammonium carbonate are used to provide NH3 to complex different metal elements. To provide the essential basis for the development of a selective recycling process for spent LIBs, this study focuses on determining the apparent leaching behaviour of cobalt, lithium, nickel, manganese and aluminium from waste cathode materials. The possible explanation of the selective ammoniacal leaching mechanism from thermodynamic aspects was proposed by Eh–pH diagrams. The response surface methodology had also been studied to further explain the interactions between the leaching agents which were based on ammonium sulphite, ammonia and ammonium carbonate. And the ammoniacal leaching mechanism has been further explored by the analysis of the interactions and the leaching residue.
Biosorption of Ni(II) by Ni(II) resistant S. cerevisiae AJ208: potential study with nutritive elements and GA modeling
Published in Journal of Dispersion Science and Technology, 2023
Jayeeta Banerjee, Nirjhar Bar, Ranjan Kumar Basu, Sudip Kumar Das
The nitrogen sources were ammonium sulfate, ammonium carbonate, urea, ammonium nitrate, ammonium chloride, ammonium phosphate, ammonium oxalate, ammonium acetate, and sodium nitrate[21] (0.002–0.006 g/ml). The calculated nitrogen percentages in the salts mentioned above keep nitrogen standard as present in sodium nitrate.