Compatibility studies salt selection

Salt selection. Unlike the reactor coolant salt, the secondary salt has no requirement for low nuclear cross sections to minimize neutron absorption. A variety of chloride and fluoride salts are potential candidates. Studies have not yet been conducted to define the preferred salt based on cost and performance requirements (compatibility with coolant salt and melting point). If appropriate low-cost salts are found, the option exists for the secondary-salt inventory to absorb days to weeks of decay heat. 

The fuel selected for use with HAN should be totally compatible and therefore, nitrate salts of amines are the natural choice for this purpose. Based on a study with aliphatic, aromatic and heterocyclic amines, aliphatic amines are considered a better choice and a formulation containing the nitrate salt of triethanolamine (TEA), that is, TEAN [(CH2OHCH2)3 NHNOJ is currently in use. HAN-based propellants consist of HAN, water and TEAN. Some typical formulations of LGP are given in Table 4.2 along with their properties. These three propellants differ from one another only in respect of the amount of water which they contain. 

In general, if an API form has stability problems in the bulk form, it is best to solve these issues via salt and form selection studies designed to discover and identify more thermodynamically stable forms prior to any excipient compatibility evaluation. It is known that different polymorphic forms and hydrated/solvated forms can have dramatically different stability profiles (23-26). 

The DSHP, which is catalyzed by C-supported Pd-based systems, may even occur in aqueous solutions, in the presence of strong mineral acids and halide ions, at temperatures inthe range 0-25 °C and at 100 atm pressure [22]. DuPont have studied extensively the use of Pt and Pd bimetallic catalysts on silica the optimal weight ratio of Ptto metal loading on silica was 0.02-0.2 the selectivity to HP obtained was about 70%, with a concentration of HP exceeding 20%. Key promoters were halogens, such as Cl or Br salts. However, the presence of strong acids may be not compatible with the epoxidation of olefins. 

The aim of this study was to investigate the compatibility between CORRPASSIV primer and topcoats based on various binders [82]. The selected topcoats have subjected to the salt spray test performed on scratched panels for the three coating systems. Underfilm corrosion, blistering, and degree of rusting were assessed. 

That different solvents, or mixtures of solvents, are critically associated with differences in selectivity coeflicients of calcium (or indeed all other types) of PVC ISEs based on organo-sensors is evident from Tables 3.2-3.10. It is highly desirable that the mediator should additionally function as a plasticizer for the PVC membrane. In view of the extensive use of PVC for fabricating the organic sensor type of ISEs, it is indeed fortunate that many of the necessary solvents fulfil this additional role. Thus di-octylphenyl phosphonate with, or without, a calcium salt is perfectly compatible with PVC. This requirement is rarely observed with alkan-l-ols which fail to plasticize the master membranes, and surface exudations are common (13). Despite this drawback, functional PVC ISEs can sometimes be fabricated (Tables 3.8,3.10) and extensive studies have been made on various solvents (Tables 3.2-3.10). 

In membrane contactor processes, various types of aqueous liquid have been employed such as pure water, aqueous solution of NaOH, KOH, amine solution, and amino acid salts. Each of the absorbent has its own specialties that define a selective process application. Li and Chen [63] conducted a study on the selection of liquid absorbent in a membrane contactor, in which they highlighted criteria for choosing the chemical solvent to be implemented in membrane contactor. The criteria included high reactivity with CO2, liquids with low surface tension, good chemical compatibility with membrane material, regenerability, low vapor pressure, and good thermal stability. Because any liquid that has surface tension lower than the critical surface tension of the polymers may wet the membrane spontaneously, the solvents must have a substantially higher surface tension than the critical surface tension... 

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