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Carbon dioxide Primary production

The Selectoxo unit can also help in a grass root plant by maintaining carbon dioxide/ammonia production ratios which is favorable for full conversion of ammonia to urea. The economics of this option are to be considered against the extra cost of carbon dioxide production by other means (either from the flue gas of the primary reformer or through back burning of extra synthesis gas)202. [Pg.156]

Pyrone reacts readily as a diene in Diels-Alder additions, but the initial adduct often loses carbon dioxide, generating a second diene that then adds a second mole of the dienophile reaction with maleic anhydride, shown below, is typical - a monoadduct can be isolated, which under more vigorous conditions loses carbon dioxide and undergoes a second addition. When the dienophile is an alkyne, methyl propiolate for example, benzenoid products result from the expulsion of carbon dioxide. Primary adducts, which have not lost carbon dioxide, can be obtained from reactions conducted at lower temperatures under very high pressure or in the presence of lanthanide catalysts. A useful example is the reaction of 2-pyrone and substituted derivatives with alkynyl boronates leading to aryl boronates 2-pyrone itself reacts in 86% yield with trimethylsilylethynyl boronate. ... [Pg.216]

In keeping with its biogenetic origin m three molecules of acetic acid mevalonic acid has six carbon atoms The conversion of mevalonate to isopentenyl pyrophosphate involves loss of the extra carbon as carbon dioxide First the alcohol hydroxyl groups of mevalonate are converted to phosphate ester functions—they are enzymatically phosphorylated with introduction of a simple phosphate at the tertiary site and a pyrophosphate at the primary site Decarboxylation m concert with loss of the terti ary phosphate introduces a carbon-carbon double bond and gives isopentenyl pyrophos phate the fundamental building block for formation of isoprenoid natural products... [Pg.1091]

Toxicity. The products of combustioa have beea studied for a number of plastic foams (257). As with other organics the primary products of combustion are most often carbon monoxide and carbon dioxide with smaller amounts of many other species depending on product composition and test conditions. [Pg.421]

Climate and Environmental Factors. The biomass species selected for energy appHcations and the climate must be compatible to faciUtate operation of fuel farms. The three primary climatic parameters that have the most influence on the productivity of an iadigenous or transplanted species are iasolation, rainfall, and temperature. Natural fluctuations ia these factors remove them from human control, but the information compiled over the years ia meteorological records and from agricultural practice suppHes a valuable data bank from which to develop biomass energy appHcations. Ambient carbon dioxide concentration and the availabiHty of nutrients are also important factors ia biomass production. [Pg.30]

The reactions of primary amines and maleic anhydride yield amic acids that can be dehydrated to imides, polyimides (qv), or isoimides depending on the reaction conditions (35—37). However, these products require multistep processes. Pathways with favorable economics are difficult to achieve. Amines and pyridines decompose maleic anhydride, often ia a violent reaction. Carbon dioxide [124-38-9] is a typical end product for this exothermic reaction (38). [Pg.450]

Decomposition products from primary and secondary dialkyl peroxides include aldehydes, ketones, alcohols, hydrogen, hydrocarbons, carbon monoxide, and carbon dioxide (44). [Pg.107]

Cyclohexylamine is miscible with water, with which it forms an azeotrope (55.8% H2O) at 96.4°C, making it especially suitable for low pressure steam systems in which it acts as a protective film-former in addition to being a neutralizing amine. Nearly two-thirds of 1989 U.S. production of 5000 —6000 t/yr cyclohexylamine serviced this appHcation (69). Carbon dioxide corrosion is inhibited by deposition of nonwettable film on metal (70). In high pressure systems CHA is chemically more stable than morpholine [110-91-8] (71). A primary amine, CHA does not directiy generate nitrosamine upon nitrite exposure as does morpholine. CHA is used for corrosion inhibitor radiator alcohol solutions, also in paper- and metal-coating industries for moisture and oxidation protection. [Pg.212]

The primary advantage of MCP is to create a large number of gas cells rapidly during mixing. These gas cells serve as nuclei for a greater expansion later in the oven. MCP also finds many uses in the products in which fast release of carbon dioxide and a low bench action are requited. Examples are pancake mixes, cookie mixes, and angel food cakes. The milling industry uses MCP in the manufacture of phosphated flour. [Pg.469]

Sodium Aluminum Sulfate (SAS). Sodium aluminum sulfate is a dehydrated double salt of aluminum and sodium sulfate. It does not react with baking soda in cold, but in the heat of oven 1 mol of SAS produces 6 mol of carbon dioxide from reacting with baking soda. Historically, SAS was one of the first materials used to Hberate carbon dioxide from baking soda. Today its primary use is in household baking powder production. It is used either alone or in combination with MCP. SAS is not recommended for use in prepared mixes due to its lack of compatibiHty with other ingredients in a mix. [Pg.469]

The per pass ethylene conversion in the primary reactors is maintained at 20—30% in order to ensure catalyst selectivities of 70—80%. Vapor-phase oxidation inhibitors such as ethylene dichloride or vinyl chloride or other halogenated compounds are added to the inlet of the reactors in ppm concentrations to retard carbon dioxide formation (107,120,121). The process stream exiting the reactor may contain 1—3 mol % ethylene oxide. This hot effluent gas is then cooled ia a shell-and-tube heat exchanger to around 35—40°C by usiag the cold recycle reactor feed stream gas from the primary absorber. The cooled cmde product gas is then compressed ia a centrifugal blower before entering the primary absorber. [Pg.457]

Combustion processes are the most important source of air pollutants. Normal products of complete combustion of fossil fuel, e.g. coal, oil or natural gas, are carbon dioxide, water vapour and nitrogen. However, traces of sulphur and incomplete combustion result in emissions of carbon monoxide, sulphur oxides, oxides of nitrogen, unburned hydrocarbons and particulates. These are primary pollutants . Some may take part in reactions in the atmosphere producing secondary pollutants , e.g. photochemical smogs and acid mists. Escaping gas, or vapour, may... [Pg.502]

Ammonia production from natural gas includes the following processes desulfurization of the feedstock primary and secondary reforming carbon monoxide shift conversion and removal of carbon dioxide, which can be used for urea manufacture methanation and ammonia synthesis. Catalysts used in the process may include cobalt, molybdenum, nickel, iron oxide/chromium oxide, copper oxide/zinc oxide, and iron. [Pg.64]

In a typical gas oil design, the lighter products overhead from the quench tower/primary fractionator are compressed to 210 psi, and cooled to about 100°F. Some Q plus material is recovered from the compressor knockout drums. The gases are ethanolamine and caustic washed to remove acid gases sulfur compounds and carbon dioxide, and then desiccant dried to remove last traces of water. This is to prevent ice and hydrate formation in the low temperamre section downstream. [Pg.103]

Codeposition of silver vapor with perfluoroalkyl iodides at -196 °C provides an alternative route to nonsolvated primary perfluoroalkylsilvers [272] Phosphine complexes of trifluaromethylsilver are formed from the reaction of trimethyl-phosphme, silver acetate, and bis(trifluoromethyl)cadmium glyme [755] The per-fluoroalkylsilver compounds react with halogens [270], carbon dioxide [274], allyl halides [270, 274], mineral acids and water [275], and nitrosyl chloride [276] to give the expected products Oxidation with dioxygen gives ketones [270] or acyl halides [270] Sulfur reacts via insertion of sulfur into the carbon-silver bond [270] (equation 188)... [Pg.716]

Transportation accounts for about one-fourth of the primary energy consumption in the United States. And unlike other sectors of the economy that can easily switch to cleaner natural gas or electricity, automobiles, trucks, nonroad vehicles, and buses are powered by internal-combustion engines burning petroleum products that produce carbon dioxide, carbon monoxide, nitrogen oxides, and hydrocarbons. Efforts are under way to accelerate the introduction of electric, fuel-cell, and hybrid (electric and fuel) vehicles to replace sonic of these vehicles in both the retail marketplace and in commercial, government, public transit, and private fleets. These vehicles dramatically reduce harmful pollutants and reduce carbon dioxide emissions by as much as 50 percent or more compared to gasoline-powered vehicles. [Pg.479]

Natural gas will continue to be substituted for oil and coal as primary energy source in order to reduce emissions of noxious combustion products particulates (soot), unburned hydrocarbons, dioxins, sulfur and nitrogen oxides (sources of acid rain and snow), and toxic carbon monoxide, as well as carbon dioxide, which is believed to be the chief greenhouse gas responsible for global warming. Policy implemented to curtail carbon emissions based on the perceived threat could dramatically accelerate the switch to natural gas. [Pg.827]


See other pages where Carbon dioxide Primary production is mentioned: [Pg.121]    [Pg.156]    [Pg.489]    [Pg.5]    [Pg.425]    [Pg.9]    [Pg.10]    [Pg.64]    [Pg.66]    [Pg.163]    [Pg.522]    [Pg.343]    [Pg.347]    [Pg.467]    [Pg.25]    [Pg.332]    [Pg.544]    [Pg.110]    [Pg.482]    [Pg.383]    [Pg.457]    [Pg.446]    [Pg.34]    [Pg.235]    [Pg.576]    [Pg.423]    [Pg.581]    [Pg.1188]    [Pg.794]    [Pg.88]    [Pg.225]    [Pg.397]   


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Carbon dioxide photosynthesis production, primary

Carbon dioxide primary

Carbon dioxide production

Carbon primary productivity

Carbon product

Carbonates production

Primary carbon

Primary carbonization

Primary productivity

Primary products

Production primary

Production/productivity primary

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