Ozonizer, Otto

Otto, H. W., and R. H. Daines. Plant injury by air pollutants Influence of humidity on stomatal apertures and plant response to ozone. Science 163 1209-1210. 1%9. 

Chemiluminescence is also shown with a few simple mineral compounds. Otto (21) expressed the opinion that, if ozone causes a luminescence in the presence of water, it acts upon impurities therein. Hydrogen sulfide gives rise to an ultraviolet chemiluminescence with ozone (Zabiezynski and Orlowski, 33). Several oxygen compounds of nitrogen, especially nitric oxide, show, under the action of ozone, a spectrum different from that of active nitrogen [Morren (20), Sarrasin (23), Strutt (26), Knauss and Murrey (17) ]. Solid phosphorus trixode becomes luminescent [Thorpe and Tutton (29)]] and so do carbon monoxide, carbonyl sulfide, and carbonyl chloride at 200 C. The first of these furnishes a band spectrum of 4000 to 5000 A. which corresponds to a bimolecular process [Trautz and Seidel (31) and Trautz and Haller (30)]. Siloxane too shows oxyluminescence [Kautsky and Zocher (16)] under the influence of ozone. 

Half of the plant uses plate ozonators of the Otto design and half ozonizers of the tubular Van der Made design. The ozonized emulsion is introduced through eight cylindrical, porous diffusers at the bottom of each column in one half of the plant in the other, it is introduced through 96 nozzles per column. 

The historical development of European ozonators and ozone production are reviewed. The OttO/ van der Made, and Siemens processes for generating ozone are described. Recent improvements and Innovations are indicated. Two distinct operations are considered conditioning of the air to be submitted to the electric discharge, and contact between the ozone and the water. 

In Europe from 1907 to 1930, three ozone generating processes were successfully submitted to the test of industrial applications the Otto, the Van der Made, and Siemens processes. Since 1930, there has been a tendency toward improving the production equipment of these processes with a view to reducing its size and eliminating certain production drawbacks, such as the too frequent breakage of dielectrics. 

Otto Ozonators. Before 1930, Otto ozonators, built and put into use in numerous municipal water treatment plants, were of the flat electrode type with two dielectrics, assembled as in arrangement A, Figure 1, and supplied with 500-cycle current. 

Figure 2. Otto ozonator, flat-electrode type, with five ozonator elements...

Figure 3. Otto ozonator with ozone-producing elements grouped in batteries of four...

The cooling of the high tension electrodes is by a means similar to that of the first Otto ozonators, except that the break in the high tension circuit is accomplished by a rain of droplets into insulating oil instead of a fall through air. 

In France. In 1938, the first silica gel dryer applied to the Otto process was put in operation. Since then, this method of drying has normally been used in all Otto ozonation plants, except the Saint-Maur plant, which alone uses coohng. 

After the ozone is produced, it must be made to act upon the water. This problem, which is a matter of bringing large volumes of gases and liquids into adequate and continuous contact, has been approached in a variety of ways. Two methods were introduced about 1930. One was developed by Otto, the other by Van der Made. 

Because of a number of problems—e.g., weakness of the perforated plates, too low an ozone concentration, too large a volume of air, and costly maintenance of the compressor and other equipment because of corrosive action of ozone— this method has been modified in later installations. The perforated plates have been eliminated, and the air is diffused through plastic diffusers. Stainless steel rotary, liquid ring compressors are used. In some cases, even the Otto method of emulseurs and selfcontact columns is employed. 

At present in Europe, water is treated with ozone according to the old Otto process or the Van der Made process. As far as is known, other processes have not become established. These two are the original systems proposed by those who introduced ozone into France. 

Figure 1 is a schematic section of the Otto sterilization apparatus, the most commonly utilized. It is used generally in combination with Otto plate ozonators. The water to be treated comes under pressure to the emuheur, a sort of water jet pump. The vacuum produced by the water is sufficient to suck in the ozonated air from the ozonator, and the mixture of the two fluids is carried to the bottom of the self-contact column, which is a tower 5 meters (16 feet 4 inches) in depth. The water falls freely from a weir at the top of the tower, where most of the gas escapes. 

The application of ozone to the oxidation of ethylene was first investigated by Schonbein 88 in 1855 but neither he nor Otto who worked somewhat later,84 succeeded in isolating the primary product of the reaction because of the heavy explosions which invariably took place. 

Cril Otto Kiemm, Locai and Regionai Ozone A Student Study Project," /. Chem. Educ, Voi. 78, 2001, 1641-1646. 

In the previous sections, we described the addition of ozone and carbenes to double bonds as cycloadditions. Cycloadditions are one of a larger class of reactions called pericyclic processes that we will meet again in several later chapters. We can class the ozone reaction as a 3 + 2-cycloaddition and the carbene addition as a 1 + 2-cycloaddition. This section will deal with 2 + 2- and 4 + 2-cycloadditions. The numbers come simply from the number of atoms in each component that we are adding together to make a new cyclic compound. The Diels-Alder reaction was first documented in 1928, and Otto Diels and Kurt Alder received the Nobel Prize for their work in 1950. In its simplest form, it involves the addition of an alkene, usually... 

Research at the Max Planck Institute for Chemistry has been at the forefront of science throughout its existence. Since the Institute s foundation in 1912, three of its directors were awarded with the Nobel Prize for Chemistry Richard Willstatter in 1915 for the revelation of the structure of chlorophyll and other plant pigments, Otto Hahn in 1944 for the discovery of nuclear fission, and Paul Cmtzen in 1995 for the elucidation of atmospheric ozone chemistry. 

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