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Chemicals from Paraffin Hydrocarbons
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Free naphthenic acids are corrosive and are mainly used as their salts and esters. The sodium salts are emulsifying agents for preparing agricultural insecticides, additives for cutting oils, and emulsion breakers in the oil industry. Other metal salts of naphthenic acids have many varied uses. For example, calcium naphthenate is a lubricating oil additive, and zinc naphthenate is an antioxidant. Lead, zinc, and barium naphthenate derivatives are wetting agents used as dispersion agents for paints. Some oil-soluble metal naphthenate derivatives, such as those of zinc, cobalt, and lead, are used as driers in oil-based paints. Among the diversified uses of naphthenate derivatives is the use of aluminum naphthenate derivatives as gelling agents for gasoline flame throwers (napalm). Manganese naphthenate derivatives are well-known oxidation catalysts.
Erosion
Published in Karlheinz Spitz, John Trudinger, Mining and the Environment, 2019
Karlheinz Spitz, John Trudinger
The seventh most abundant element in the earth, sodium occurs mainly as soluble salts, notably sodium chloride (table salt). Metallic sodium has relatively few uses but sodium salts are widely used. Sodium chloride is widely used for flavour enhancement, de-icing and in the production of other sodium compounds. Sodium hydroxide (caustic soda) is used in a wide range of chemical processes, while sodium bicarbonate is used in baking. The main source of sodium (sodium chloride) is produced by the evaporation of sea water and brines, and from deposits of rock salt.
Boilers
Published in A.J. Pansini, K.D. Smalling, Guide to Electric Power Generation, 2020
Calcium salts may include calcium carbonate (lime, chalk, marble), calcium sulfate (plaster of Paris, gypsum), both of which are very soluble in water. Magnesium carbonate, bicarbonate, sulfate (Epsom salt), chloride, are also very soluble in water. Sodium salts soluble in water include carbonate (soda ash), sulfite, chloride (common table salt) and hydroxide (caustic soda). Silica dioxide, or sand, may combine with some of the other salts and be deposited as scale.
Recovery and reuse of alginate in an immobilized algae reactor
Published in Environmental Technology, 2021
Olga Murujew, Rachel Whitton, Matthew Kube, Linhua Fan, Felicity Roddick, Bruce Jefferson, Marc Pidou
Preliminary tests were run to identify the most suitable chemical for bead dissolution. Three sodium salts were investigated: sodium chloride (NaCl), sodium carbonate (Na2CO3) and trisodium citrate (Na3C6H5O7; Na-citrate). These salts were selected because they are readily available and cheap and/or had been previously used to dissolve calcium alginate [8]. Solutions were made up to at least 0.5 M to have excess sodium ions. Algae beads (1 g, 61–67 beads) were added to 25 mL of each of the sodium solutions and magnetically stirred for 20–150 min. In the subsequent experiments, beads (EB and AB) were dissolved by stirring for 1–2 h in 0.5 M Na-citrate solution (Merck, Batch No MC1M610493). Preliminary tests showed that a ratio of 1:2 Na-citrate:sodium alginate was suitable for dissolution of the beads. Where stated (i.e. supplemented beads), sodium alginate powder was added (equivalent to 1% weight/volume) to the recovered alginate (RA) solutions to overcome the dilution incurred by dissolution. After the dissolution of the algae beads, the algal biomass was separated with vacuum filtration with a 3 µm cellulose acetate filter. However, this proved inefficient with regard to alginate yield in the filtrate. A centrifugation method, detailed below, was subsequently used for the separation of the algal biomass from the alginate for the continuous nutrient removal experiments.