Stabilized liquid bromine

Table 2 Storage stability of chlorine and stabilized liquid bromine...

Significant industrial demand for a more practical stabilized liquid bromine product has been known for several years. Until the invention and commercial development of STABREX, there was no practical means to overcome the inherent instability, volatility, and handling hazards of liquid bromine. The new technology solves several longstanding technical problems that bromine manufacturers tried, unsuccessfully, to overcome for 15 years. The practical use of STABREX stabilized liquid bromine and its... 

STABREX Stabilized Liquid Bromine is a trademark of Nalco Chemical Company... 

A derivation of these sodium bromide activation programs is the recent introduction of stabilized liquid bromine, in which the two primary reactants are present in the correct ratio, in one drum, and remain stabilized against reaction until required. 

The most recent enhancement of bromine biocide chemistry is the development of a stabilized single liquid bromine, under the brand Stabrex , from Nalco (now owned by Degremont/Suez Lyonnaise Des Eaux). The product is most likely a sodium hypochlorite/sodium bromide mix, stabilized with sulfamic acid. It contains 14% available halogen as Br (6% as Cl), and is stable for several months. Stabrex probably has some benefits over other bromine chemistries, but is also a premium priced product. 

STABREX is easier and simpler to use compared to any other oxidant available for industrial water treatment. The product is pumped directly from returnable transporters (PortaFeed Systems)17 with standard chemical feed equipment. Previously, the only practical ways to apply bromine were to oxidize bromide solutions on-site with chlorine in dual liquid feed systems, or with one of the solid organically-stabilized bromine products applied from sidestream erosion feeders. The former is cumbersome and complex, and the latter is prone to dusting and difficult to control. Other oxidants require complex handling and feed of toxic volatile gases, unstable liquids, multiple-component products, or reactive solids. Simplicity in use results in reduced risk to workers and to the environment. 

Brominated phosphate heated in a glass tube in air at 300°C for 30 minutes remains a water-white liquid. This was compared with commercial bromine-containing flame retardants which melt they all turn color. The excellent color stability of this brominated phosphate ester makes it suitable for the high temperature processing of engineering plastics. 

When chlorination or bromination of alkenes is carried out in the gas phase at high temperature, addition to the double bond becomes less significant and substitution at the allylic position becomes the dominant reaction.153-155 In chlorination studied more thoroughly a small amount of oxygen and a liquid film enhance substitution, which is a radical process in the transformation of linear alkenes. Branched alkenes such as isobutylene behave exceptionally, since they yield allyl-substituted product even at low temperature. This reaction, however, is an ionic reaction.156 Despite the possibility of significant resonance stabilization of the allylic radical, the reactivity of different hydrogens in alkenes in allylic chlorination is very similar to that of alkanes. This is in accordance with the reactivity of benzylic hydrogens in chlorination. 

Polyolefin resins contain only carbon and hydrogen, and additives, such as some antioxidants and UV stabilizers. Moreover, the presence of hetero-elements, such as chlorine and bromine is undesirable, as these elements distribute over the three product phases-gas, liquid, and solids, reducing the market potential and value of each of these. Studying their elimination is a major consideration in developing processes for mixed plastics. 

Benzyl bromide is prepared by the direct bromination of toluene in the. same way as xylyl bromide is obtained from xylene. In its pure. state, benzyl bromide Is a transparent liquid, with a specific gravity of 1.44, which boils at 201 C. (393.8 F.), yielding vapor 0 times heaWer than air and with a pleasant aromatic odor resembling water cress. It is inuoliiblo in water and is only very slowly decomposed thereby. Its great cliemical stability, low vapor pressure, 2.0 mm. Hg at 20 C. (68 F.), and low volatility, 2.4 mg. per liter at 20 C. (68 F.), assures its j>ersistence on the terrain. 

AMYL ALDEHYDE (110-62-3) CsH,oO Highly flammable liquid. Peroxidizable material. Forms explosive mixture with air (flash point 54°F/12°C Fire Rating 3). Violent reaction with strong oxidizers, bromine, ketones. Incompatible with strong acids (may cause exothermic selfcondensation or polymerization reactions) ammonia, strong caustics, amines, amides, organic hydroxides. Unless stabilized, with antioxidants (to retard autoxidation), this... 

---