Carbon dioxide fertilization

A global extension to this question is whether the world is as a whole down regulated or if carbon dioxide fertilization is actually occurring. U.S. Forest Service data for the past 70 years was analyzed to find if forest growth is currently... 

The amount of carbon per unit area for a given ecosystem or vegetation type, based on climatic conditions, topography, vegetative-cover type and amount, soils, and maturity of the vegetative stands, carbon dioxide fertilization... 

Urea can be considered the amide of carbamic acid, NH2COOH, or the diamide of carbonic acid, CO(OH)2. At room temperature, urea is colorless, odorless, and tasteless. Properties are shown ia Tables 1—4. Dissolved ia water, it hydrolyzes very slowly to ammonium carbamate (1) and eventually decomposes to ammonia and carbon dioxide (qv). This reaction is the basis for the use of urea as fertilizer (qv). 

An additional mole of ammonium sulfate per mole of final lactam is generated duting the manufacture of hydroxylamine sulfate [10039-54-0] via the Raschig process, which converts ammonia, air, water, carbon dioxide, and sulfur dioxide to the hydroxylamine salt. Thus, a minimum of two moles of ammonium sulfate is produced per mole of lactam, but commercial processes can approach twice that amount. The DSM/Stamicarbon HPO process, which uses hydroxylamine phosphate [19098-16-9] ia a recycled phosphate buffer, can reduce the amount to less than two moles per mole of lactam. Ammonium sulfate is sold as a fertilizer. However, because H2SO4 is released and acidifies the soil as the salt decomposes, it is alow grade fertilizer, and contributes only marginally to the economics of the process (145,146) (see Caprolactam). 

The ammonium carbamate then loses a molecule of water to produce urea [57-13-6] CO(NH2)2- Commercially, this is probably the most important reaction of carbon dioxide and it is used worldwide ia the production of urea (qv) for synthetic fertilizers and plastics (see Amino resins Carbamic acid). 

Carbon dioxide is sometimes added to irrigation water, in the same manner as fertilizer ammonia, in hard water regions. Carbon dioxide is also used with other gases in treating respiratory problems and in anesthesia. 

The carbon dioxide removed in synthesis gas preparation can be reacted with ammonia, to lonn urea CO(NH2)2- This is an excellent fertilizer, highly concentrated in nitrogen (46.6%) and also useful as an additive in animal feed to provide the nitrogen for formation of meat protein. Urea is also an important source of resins and plastics by reacting it with formaldehyde from methanol. 

Urea, NH2CONH2, is the diamide of carbonic acid, (HO)2CO, and is manufactured in large volume for use in fertilizers and plastics by the reaction of carbon dioxide and ammonia. 

In this study, the main aim was to investigate how maize fertilized with wastewater at 120 kg N ha-1 affected crop growth, soil properties and the production of carbon dioxide (C02), methane (CH4) and nitrous oxide (N20) compared with plants fertilized with urea [16]. 

As the one of the main end products of protein metabolism in living organisms, urea is a primary source of organic nitrogen in soil (from animal urine, fertilizers, etc.). Monitoring the level of urea is important for medicine, as well as for environmental protection. Urease is an enzyme that breaks the carbon-nitrogen bond of amides to form carbon dioxide, ammonia and water. This enzyme is widely used for determination of urea in... 

Considering the full production cycle, methanol from biomass emits less carbon dioxide than ethanol from biomass. This is because short rotation forestry, the feedstocks of methanol, requires the use of less fertilizer... 

Urea, another common example of an amide, is made from the reaction between carbon dioxide gas, CO2, and ammonia, NH3. Urea was the first organic compound to be synthesized in a laboratory. It is found in the urine of many mammals, including humans, and it is used as a fertilizer. 

Although urea is an organic compound, it is best discussed with other ammonia-derived synthetic nitrogen compounds, especially in view of its importance to the fertilizer industry like the other compounds in this chapter. It is made easily from ammonia and carbon dioxide. 

A 3 1 molar ratio of ammonia and carbon dioxide (excess ammonia) are heated in the autoclave for 2 hr at 190°C, and 1500-3000 psi. The mixture formed is approximately 35% urea, 8% ammonium carbamate, 10% water, and 47% ammonia. It is cooled and the ammonia is distilled at 60 °C. The residue from the ammonia still enters a crystallizer at 15°C. More ammonia is removed by vacuum. The resulting slurry is centrifuged to get solid urea. All excess nitrogenous materials from the liquid are combined and processed into liquid fertilizer, which contains a mixture of all these materials. 

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