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Secondary final product

The potential function of each chemical is also indicated PR = primary rawmaterial, SR = secondary raw material, I = intermediate, PF = primary final product, SF = secondary final product. [Pg.87]

Protonolysis of Pb(C2H5)4 leads to cleavage of one or two Pb-C bonds, depending on the acid and the reaction conditions, and formation of tri- or diethyllead compounds. These primary products tend to redistribute or to decompose, and in many instances, especially at elevated temperatures, lead(II) derivatives of the acid are the secondary final products, either alone or as contaminants of the primary products. No acidolytic cleavage of a third Pb-C bond or even of all four Pb-C bonds of Pb(C2Hs)4 has been observed, thus, monoethyl-lead compounds or inorganic lead(IV) compounds cannot be obtained by acidolysis of... [Pg.144]

The reaction sequence is successful because reverse, ring-contraction reactions are unlikely and because only the final product contains a secondary lactam group, which is depro-tonated under the reaction conditions. [Pg.250]

Miscellaneous Reactions. Sodium bisulfite adds to acetaldehyde to form a white crystalline addition compound, insoluble in ethyl alcohol and ether. This bisulfite addition compound is frequendy used to isolate and purify acetaldehyde, which may be regenerated with dilute acid. Hydrocyanic acid adds to acetaldehyde in the presence of an alkaU catalyst to form cyanohydrin the cyanohydrin may also be prepared from sodium cyanide and the bisulfite addition compound. Acrylonittile [107-13-1] (qv) can be made from acetaldehyde and hydrocyanic acid by heating the cyanohydrin that is formed to 600—700°C (77). Alanine [302-72-7] can be prepared by the reaction of an ammonium salt and an alkaU metal cyanide with acetaldehyde this is a general method for the preparation of a-amino acids called the Strecker amino acids synthesis. Grignard reagents add readily to acetaldehyde, the final product being a secondary alcohol. Thioacetaldehyde [2765-04-0] is formed by reaction of acetaldehyde with hydrogen sulfide thioacetaldehyde polymerizes readily to the trimer. [Pg.51]

Diester/Ether Diol of Tetrabromophthalic Anhydride. This material [77098-07-8] is prepared from TBPA in a two-step reaction. First TBPA reacts with diethylene glycol to produce an acid ester. The acid ester and propylene oxide then react to give a diester. The final product, a triol having two primary and one secondary hydroxyl group, is used exclusively as a flame retardant for rigid polyurethane foam (53,54). [Pg.470]

Secondary Plasticizers. Also known as extenders, secondary plasticizers continue to play a significant role ia flexible PVC formulations. They do not impart flexibiHty to the PVC resia alone, but when combiaed with a primary plasticizer act ia such a way as to add flexibiHty to the final product. [Pg.123]

Secondary Timber Products. Secondary timber products are products manufactured from primary timber products. Secondary products can be sold directly to the final consumer or can requite additional processing before reaching the final consumer. The wide diversity of products manufactured from primary timber products makes it difficult to precisely define secondary products. Lumber, for example, is clearly a secondary product because it is manufactured from roundwood and typically requites further processing before reaching its final use. Wooden furniture is considered a final product, not a secondary product because it is made from lumber or other secondary timber products. In general, products made from secondary timber products were not included in this analysis. [Pg.333]

The size distribution of the final product may become wide since the monodispersity cannot be controlled due to the formation of the copolymer particles with a secondary nucleation. [Pg.216]

Pyrolyses of formates, oxalates and mellitates yield CO and C02 (H2, H20 etc.) as the predominant volatile products and metal or oxide as residue. It is sometimes possible to predict the initial compositions from thermodynamic considerations [94], though secondary reactions, perhaps catalyzed by the solids present, may result in a final product mixture that is very different. The complex mixtures of products (hydrocarbons, aldehydes, ketones, acids and acid anhydrides) given [1109] by reactants containing larger organic groupings makes the collection of meaningful kinetic data more difficult, and this is one reason why there are relatively few rate studies available for the decompositions of these substances. [Pg.229]

The addition, therefore, follows Markovnikov s rule. Primary alcohols give better results than secondary, and tertiary alcohols are very inactive. This is a convenient method for the preparation of tertiary ethers by the use of a suitable alkene such as Me2C=CH2. Alcohols add intramolecularly to alkenes to generate cyclic ethers, often bearing a hydroxyl unit as well. This addition can be promoted by a palladium catalyst, with migration of the double bond in the final product. Rhenium compounds also facilitate this cyclization reaction to form functionalized tetrahydrofurans. [Pg.996]

Typically, the reaction mechanism proceeds as follows [6], By photoreaction, two chlorine radicals are formed. These radicals react with the alkyl aromatic to yield a corresponding benzyl radical. This radical, in turn, breaks off the chlorine moiety to yield a new chlorine radical and is substituted by the other chlorine, giving the final product. Too many chlorine radicals lead to recombination or undesired secondary reactions. Furthermore, metallic impurities in micro reactors can act as Lewis catalysts, promoting ring substitution. Friedel-Crafts catalyst such as FeClj may induce the formation of resin-Uke products. [Pg.613]

Any process which is a consequence of discrete tasks that have to follow a predefined sequence from raw materials to final products is a batch process. This predefined sequence is commonly known as a recipe. The primary features of any comprehensive recipe are the quantities of materials that have to be processed by individual tasks as well as the duration of each task within the recipe. The secondary features are the operating conditions of the various tasks, and in less common circumstances, the locality or geographic position of the task at hand. In processes wherein safety is of great concern, it might be necessary to perform a particular task in a designated area equipped with relevant safety features. [Pg.3]

Primary amines react readily with nitrosating agents (Scheme 3.1) to provide deamination products. The intermediates, primary nitrosamines (RNHNO), are not stable therefore after a series of rapid reactions, they give rise to the diazonium ion (RN2+), and then decompose to the final products. The reactions of secondary amines can stop at the nitrosamine stage, since no a-hydrogen atoms are available for the necessary proton transfer reactions, which lead to diazonium ion formation. [Pg.58]

In addition to the primary processes, the following secondary processes are present in all three companies maintenance, quality and logistics. These processes together with the primary process constitute the operational process, where the initial data for this study was collected. The maintenance process performs scheduled and unscheduled maintenance activities at the different technical installations. The quality process takes samples at different points in the primary process to check the intermediate or final product according to product specifications. The logistic process takes care of the material flow and storage of materials. [Pg.123]


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See also in sourсe #XX -- [ Pg.84 ]

See also in sourсe #XX -- [ Pg.84 ]




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