Disposal of hydrogen

The enzymes GSH peroxidase, GSH reductase and SOD collaborate to ensure that the red cell is protected from the effects of methaemoglobin and superoxide. Disposal of hydrogen peroxide may occur by catalase, in a reaction which is also dependent on NADPH. This vital coenzyme is provided via the PPP. Although the PPP operates in all cell types for the provision of pentose sugars and nucleotides, its role in the RBC is more directed to cell survival than cell division. 

Handling precautions for the gas or anhydrous liquid have been detailed.8 A polythene condenser for disposal of hydrogen fluoride has been described.8,9... 

Cytochrome P-450 reductase (present in cell nuclear membranes) catalyzes reduction of the anthracyclines to semiquinone free radicals. These in turn reduce molecular 02, producing superoxide ions and hydrogen peroxide that mediate single strand scission of DNA (Figure 38.10). Tissues with ample superoxide dismutase (SOD) or glutathione peroxidase activity are protected.6 Tumors and the heart are generally low in SOD. In addition, cardiac tissue lacks catalase and thus cannot dispose of hydrogen peroxide. This may explain the cardiotoxicity of anthracyclines. 

W. R. Thompson and C. S. Boncore, Design and Development of a Test Facility for the Disposal of Hydrogen at High Flow Rates, 1966 Cryogenic Engineering Conference, Boulder, Colo. 

A snag was that these companies now had to dispose of hydrogen chloride. The most elegant solution was to react this with acetylene in a separate stage, to give what became known as the Balanced Process. This scheme became a driving force for naphtha cracking to mixtures of ethylene and acetylene, as exemplified by the Wulff process. 

The most common method of disposing of hydrogen is by venting to the atmosphere. Venting should be done through a vent stack that discharges at an elevated point. It should be done at a controlled rate in an isolated area remote from sources of ignition and away from air intakes. 

Disposal of hydrogen chloride may be accomplished by slowly discharging the gas into a scrubber or other suitable receptacle containing approximately 15 percent sodium hydroxide (or other alkali) and water. It is necessary to place a reverse flow check valve or trap in the discharge line to prevent the caustic solution from drawing back into the cylinder. 

Routine disposal of hydrogen fluoride may be accomplished by discharging the gas directly into a counterflow caustic (KOH) scrubber. The system should contain an antisuckback device to prevent reverse flow into the cylinder. The scrubber vent should discharge into a well-ventilated area away from personnel and building ventilation air intakes, and be monitored for acid breakthrough. 

Emissions, spills, inventory, and disposal of hydrogen sulfide are also regulated under the Superfund Act and under the Resource Recovery and Conservation Act in the United States. The reportable quantity (RQ) for hydrogen sulfide is 100 lb (45.4 kg). 

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