Reactive chemical production

Supervisor safety training applies to all levels of Dow management and is tailored to the individual s responsibility. For example, a manager with global responsibilities for reactive chemical products which are new to him may be required to conduct a reactive chemicals review for the products and then pass a written examination. 

Research on the spontaneous explosion of lead azide was recently reviewed by Fox et al. [123], who discuss the main three hypotheses which have been suggested to explain the phenomenon. These involve (1) the release of stored energy sufficient to cause explosion [124], (2) reactive chemical products or intermediates formed in the solution from which the lead azide is growing [122,125], and (3) spark initiation caused by discharge between growing crystals [121] ... 

A sohd waste is considered hazardous if it is either a Hsted waste or a characteristic waste. Listed wastes include a Hst of specific processes that generate a waste and a Hst of discarded commercial chemical products. There are four hazardous waste characteristics ignitabiHty, corrosivity, reactivity, and toxicity. The last refers to the leachabiHty of a waste and the resultant toxicity in the groundwater using the analytical method referred to as toxicity characteristic leaching procedure (TCLP). A Hst of substances included under TCLP is shown in Table 1. 

Reactive Chemicals Exposure. The ha2ards associated with exposure to reactive chemicals vary with the chemicals produced. The multitude of chemicals produced electrochemically precludes a detailed discussion of these ha2ards. Material Safety Data Sheets (MSDS) are available from suppHers. Anyone contemplating the production of a chemical must become thoroughly familiar with all safety, health, and environmental aspects of such production. 

Ethylene oxide is a highly reactive compound, and so is used iudustriaHy as an iatermediate for many chemical products. The three-membered ring is opened iu most of its reactions. These reactions are very exothermic because of the tremendous ring strain iu ethylene oxide, which has been calculated (39). Reviews of ethylene oxide reactions are given iu References 40 and 41. 

Understanding the Reactive Chemicals and Reactive Chemicals Systems Involved The main business of most chemical companies is to manufacture products through the control of reactive chemicals. The reactivity that makes chemicals useful can also make them hazardous. Therefore, it is essential that people who design or operate chemical processes understand the nature of the reactive chemicals involved. 

Two standard estimation methods for heat of reaction and CART are Chetah 7.2 and NASA CET 89. Chetah Version 7.2 is a computer program capable of predicting both thermochemical properties and certain reactive chemical hazards of pure chemicals, mixtures or reactions. Available from ASTM, Chetah 7.2 uses Benson s method of group additivity to estimate ideal gas heat of formation and heat of decomposition. NASA CET 89 is a computer program that calculates the adiabatic decomposition temperature (maximum attainable temperature in a chemical system) and the equilibrium decomposition products formed at that temperature. It is capable of calculating CART values for any combination of materials, including reactants, products, solvents, etc. Melhem and Shanley (1997) describe the use of CART values in thermal hazard analysis. 

There are many applications for silicone adhesives, sealants, or coatings where the condensation curing systems are not suitable. This is because they are relatively slow to cure, they require moisture to cure that can itself be in some cases uncontrollable, and they evolve by-products that cause shrinkage. Adhesives needed in automotive, electronics, microelectronics, micro electromechanical systems, avionic, and other hi-tech applications are usually confined to vei7 small volumes, which can make access to moisture difficult. Also, their proximity to very sensitive mechanical or electronic components requires a system that does not evolve reactive chemicals. 

The testing of chemicals/wastes to establish the nature of their hazard capacity/threat in accordance with regulatory requirements falls into four categories (1) reactivity, (2) ignitability/flammability, (3) corrosivity, and (4) EP toxicity. Commercial chemical products, specific wastes, and wastes from specific processes may be listed as hazardous wastes because they are known to present toxic hazards in the manner of the tests above and/or are known to present serious toxic hazards to mammals/humans. In the discussion to follow, various chemical groups will be examined primarily in the context of reactivity, ignitability, and corrosivity. 

The control of chemical reactions (e.g., esterification, sulfonation, nitration, alkylation, polymerization, oxidation, reduction, halogenation) and associated hazards are an essential aspect of chemical manufacture in the CPI. The industries manufacture nearly all their products, such as inorganic, organic, agricultural, polymers, and pharmaceuticals, through the control of reactive chemicals. The reactions that occur are generally without incident. Barton and Nolan [1] examined exothermic runaway incidents and found that the principal causes were ... 

Experience has shown that reactive chemistry hazards are sometimes undetected during bench scale and pilot plant development of new products and processes. Reactive chemistry hazards must be identified so they can be addressed in the inherent safety review process. Chemists should be encouraged and trained to explore reactive chemistry of "off-normal operations. Simple reactive chemicals screening tools, such as the interactions matrix described in Section 4.2, can be used by R D chemists. 

Isoprene is the second important conjugated diene for synthetic rubber production. The main source for isoprene is the dehydrogenation of C5 olefins (tertiary amylenes) obtained by the extraction of a C5 fraction from catalytic cracking units. It can also be produced through several synthetic routes using reactive chemicals such as isobutene, formaldehyde, and propene (Chapter 3). 

Contractors, contract manufacturers, transporters, warehouses, and end users of reactive chemicals should be informed not only of chemical reactivity hazards, but provided information or training on how to control them. This should be done as part of product life-cycle management and Responsible Care/Product Stewardship. Specific issues needing to be addressed may include but probably are not limited to those that are highlighted during the hazard/risk analyses (Section 4.5), including ... 

Develop new less-energetic chemical reaction systems for product manufacture, including alternate catalytic and biological routes where appropriate Emphasize need to develop economically viable inherently safer systems at the research and development stages of new process development Develop new process equipment and strategies for product manufacture using lower inventories of reactive chemicals, error tolerant approaches, and process conditions further from limits of control where appropriate... 

There are OSHA standards designed to protect employees from acute chemical hazards resulting lfom reactive incidents-including fires, explosions, and toxic releases. The Hazard Communication Standard (29 CFR 1910.1200) requires chemical manufacturers to evaluate chemicals produced or handled in their workplace and to communicate the hazards associated with the products they produce via labels and MSDSs. The standard also requires all employers to provide information to employees about the hazardous chemicals to which they could be exposed. The PSM Standard (29 CFR 1910.119) requires employers to prevent or minimize the consequences of catastrophic releases of highly hazardous chemicals, including highly reactive chemicals. 

Reactive chemical process safety Systematic identification, evaluation, and control of reactive hazards at all phases of the production life cycle-from R D to pilot plant, change management, and decommissioning and for all types of operations-from storage or manufacturing to packaging or waste processing. 

The company strongly supports owner responsibility on the part of the production leaderknowing reactive chemicals and their process hazards, participating in the establishment and maintenance of corporate memory, and demonstrating a fundamental understanding of reactive chemical hazards within the facility within 90 days of any new assignment. 

Biological systems have learned to generate and tame highly reactive chemical species such as NO, FT, 0 2, HO, and oxene, in other words to produce and trap them in nano-environments where they can react productively rather than deleteriously. But biological systems have also learned a contrasting strategy, which is to enhance the chemical reactivity of a mild molecule such as water. As illustrated in this book, a diversity of enzyme mechanisms have been discovered by nature to render water more nude-... 

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