Scavenger system, advantage

The caustic is usually received as a 50% solution and diluted to 20% for use in the process. Softened water is desirable as the diluent to avoid scaling problems. In most oil field installations, the spent solution is diluted with production water and disposed of by injection into the formation. The overall process is more complex than most batch systems. In addition to the static mixers and separators, the process needs storage tanks for concentrated and dilute caustic and for spent solution recycle and makeup pumps and an instru-mentation/control system. The process has several advantages over other scavenging systems, including the use of a readily available, low-cost chemical compact size and the production of a waste product, NaHS, which has the potential for reuse in other industrial processes such as paper manufacture. 

However, it is not clear what advantages there would be to the enzyme to operate such a system, unless one metal could rapidly scavenge N2 from solution and then can pass it on to a metal center capable of activating the N2 toward hydronation. 

After about 30 min the reaction ceases. At this stage the boron trifluoride and the excess boron trichloride must be removed. One way is to open valve 1 and pump them into the vacuum system (which should have a liquid-nitrogen scavenger trap). It is a considerable advantage of the preparative method that all the reagents and products, except uranium hexachloride, are volatile. 

One of the major advantages of a molecular sieve system is the almost complete removal of heavy and unsaturated hydrocarbons, notably acetylene. Acetylene if precipitated out of LOX will detonate. It is, therefore, very important to monitor and keep acetylene levels signi cantly belo w the solubility limits, 8 ppm in LOX at 20 psia (138 kPa). In a reversing ASU it is necessary to add cryogenic silica gel adsorbers to scavenge any acetylene entering the column system. 

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