Boron recycle system

BRS—boron recycle s) em BTRS—boron thermal regeneration s) em CCW—component coolir water HX—heat exchanger RCS—reactor coolant system RHRS—residual heat removal system RMW—reactor makeup water RWST—refuelii water storj e tank WPS (L)—waste processii system (liquid)... 

Reduction of the liquid radioactive effluent discharged to the environment as a result of boron recycling, because relatively little boric acid is used during power operation as load follow is accomplished with grey rods and without changes in the reactor coolant system boron concentration. 

Boron Soils Ultrasound-assisted bleaching UV-Vis up to 35 pg g 1 Flow injection system bleaching unit in the sampling loop bleaching solution under recycle Azomethine-H as the colour-forming reagent [419]... 

Furthermore, a vast number of organometallic catalyzed reactions can be performed in a biphasic manner thus proving that also uncommon reactions may be worth to be investigated in liquid/liquid systems. For instance, Braddock describes the atom economic nitration of aromatics in a two-phase process [192], Nitration of aromatics leads usually to excessive acid waste streams and the classical Lewis acid catalysts such as boron trifluoride are destroyed in the aqueous quench after the reaction thus making any recycle impossible. In the method of Braddock the ytterbium triflate catalyst is solved in the aqueous phase and can be recycled by a simple evaporative process. Monflier and Mortreux [193] investigated the nickel catalyzed isomerization of olefins, for instance allylbenzene, in a two phase system yielding good yields of cis- and trans-methylstyrene. 

The method in which palladium complexes with hydrophilic phosphines are used in a biphasic system of water-organic solvent can be considered complementary to the standard protocol. In this case, boronate and palladium catalyst reside in the aqueous phase, while halide substrate is in the organic phase. In order for the reaction to run, the latter should be partitioned into the aqueous phase. Alternatively, oxidative addition may occur at the interface. Due to the low efQcienc of both methods, high loads of palladium catalyst and phosphine are required. Recycling is possible but is hampered by the accumulation of inorganic salts (hahde, borate) in the aqueous layer. 

Kaboudin B, Mostafalu R, Yokomatsu T (2013) FejO nanoparticle-supported Cu(ll)-p-cyclodextrin complex as a magnetically recoverable and reusable catalyst for the synthesis of symmetrical biaryls and 1,2,3-triazoles from aryl boronic acids. Green Chem 15 2266-2274 Roy S, Chatteijee T, Islam SM (2013) Polymer anchored Cu(II) complex an efficient and recyclable catalytic system for the one-pot synthesis of 1,4-disubstituted 1,2,3-triazoles starting from anilines in water. Green Chem 15 2532-2539... 

Most nuclear power plants today are operated as base load plants, but with some ability to load-follow. For PWRs, this load following capability is achieved by means of systems that manage the boron concentration of the reactor coolant water by recycling the boron in and out, on a short time scale. This requires elaborate and complicated boron and water handling systems outside the containment, and results in restrictions on the rate of load follow available. 

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