Water reactive

Although numerous mud additives aid in obtaining the desired drilling fluid properties, water-based muds have three basic components water, reactive soHds, and inert soHds. The water forming the continuous phase may be fresh water, seawater, or salt water. The reactive soHds are composed of commercial clays, incorporated hydratable clays and shales from drilled formations, and polymeric materials, which may be suspended or dissolved in the water phase. SoHds, such as barite and hematite, are chemically inactive in most mud systems. Oil and synthetic muds contain, in addition, an organic Hquid as the continuous phase plus water as the discontinuous phase. 

A weigh tank containing chlorosulfonic acid needed to be cleaned to remove salt deposits. The salt deposits precipitated from the material and occasionally plugged the downstream control valve. Since the material was water reactive, heptane was chosen to clean the vessel. Chemists had not anticipated the material would be reactive with heptane. While cleaning the vessel the pressure... 

Process materials may be pyrophoric, water reactive, strong oxidizers or strong reducers. 

Water reactivity of chemicals involved in reaction. Possibility of runaway. 

Clean and chemically dry vessel prior to charging water reactive material... 

Spontaneous Pyrophoric deposit Deposits Water reactive Sulphides Oily rags, oil impregnation of lagging Heat transfer salt ... 

Peroxides — Compounds containing the ion are hazardous primarily as oxidizing agents but also as water reactives. An example is the liberation of oxygen... 

Carbides, which are binary compounds containing anionic carbon, occur as covalent and as salt-like compounds. The salt-like carbides are water-reactive and, upon hydrolysis, yield flammable hydrocarbons. Typical hydrolysis reactions include ... 

Suong oxidizers have more potential incompatibilities than perhaps any other chemical group (with the exception of water reactive substances). It is safe to assume that they should not be stored or mixed with any other material except under carefully controlled conditions. Common oxidizing agents listed in decreasing order of oxidizing strength include ... 

Chemical Reactivity - Reactivity with Water. Reacts slowly with water, but considerable heat is liberated when contacted with spray water Reactivity with Common Materials Corrodes iron, steel and other metals Stability During Transport Stable Neutralizing Agents for Acids and Caustics Dilute with water and use sodium bicarbonate solution to rinse Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Chemical reaction sources catalysis, reaction with powerful oxidants, reaction of metals with halocarhons, thermite reaction, thermally unstahle materials, accumulation of unstahle materials, pyrophoric materials, polymerization, decomposition, heat of adsorption, water reactive solids, incompatihle materials. 

Is the material water reactive (A water reaedve material violently react with water to produce a toxic or flammable gas.)... 

Gibson D, Weber, Handbook of Selected Properties of Air and Water Reactive Materials , NAD-RDTR-144 (1969) 25)P.M. Kirke-... 

Pyrophoric deposit Deposits Water reactive Sulphides... 

For reaction of benzoyl chlorides in water, reactivity follows the electronreleasing ability of p-substituents, and there are striking differences in the micellar effects (Table 7). With electron-withdrawing substituents k+/k > 1, but its value progressively decreases with increasing electron release from a p-substituent. Thus an increase in electron release changes k+/k from values characteristic of a carbonyl addition reaction to values characteristic of SN reactions at saturated carbon. This classification also... 

Water-reactivity Release of water-reactive material and energetic reaction with water or humidity... 

The potential thermal hazards associated with thermally unstable substances, mixtures, or reaction masses are identified and evaluated as in the flow charts Figures 2.3, 2.4, and 2.5. The potential hazards posed by reactivity—water reactivity, pyrophoricity, flammability, oxidizer contact, and so forth—are also included in Figure 2.3. The individual boxes in the flow charts are discussed below ... 

Several tests have been developed to identify the hazards of reactive substances [10]. Test methods for determining pyrophoric properties, water reactivity, and oxidizing properties (Box 17) are discussed in Section 2.3.4. 

Substances that are reactive with ubiquitous substances such as air (spontaneously combustible/pyrophoric, peroxide-forming), water (water-reactive), or ordinary combustibles (oxidizers)... 

Pyrophoric and other spontaneously combustible substances will generally be identified as such on their product literature, material safety data sheets (MSDSs), or International Chemical Safety Cards (ICSCs). If transported, these substances should be identified as DOT/UN Hazard Class 4.2 materials for shipping purposes and labeled as spontaneously combustible. For pyrophoric substances, the NFPA 704 diamond for container or vessel labeling has a red (top) quadrant with a rating of 4, indicating the highest severity of flammability hazard (NFPA 704, 2001). Note that pyrophoric materials often exhibit one or more other reactivity hazards as well, such as water reactivity. 

Water-Reactive Substances Water-reactive substances will chemically react with water, particularly at normal ambient conditions. For fire protection purposes, a material is considered water-reactive if a gas or at least 30 cal/g (126 kj/kg) of heat is generated when it is mixed with water (NFPA 704, 2001), using a two-drop mixing calorimeter. 

Water reactivity can be hazardous by one or more of several mechanisms. The heat of reaction can cause thermal bums, ignite combustible materials, or initiate other chemical reactions. Flammable,... 

Substances that are water-reactive will nearly always be identified as such on their MSDSs or ICSCs. They may be identified as DOT/UN Hazard Class 4.3 materials for shipping purposes and labeled as dangerous when wet. However, some water-reactive materials are classified otherwise. Acetic anhydride is designated Class 8 it may also be identified as a combustible liquid. 

The means by which a quench system works depends on the nature of the reactive material e.g., for water-reactive materials, a quench system will destroy the material in a last-resort situation and generally form less-hazardous products, and will at the same time absorb some of the heat of reaction. Most quench systems are designed to both cool down and dilute a material that may be reacting uncontrollably the quenching medium may also actually interfere with the chemical reaction or deactivate a catalyst. 

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