Ammonia nitric acid production from

If similar processes could be developed at energy conversion efficiency levels that are comparable to the present day SMR-based NH3 synthesis plants, then it would be possible to realize a major reduction in the production costs of ammonia-borane complex. We note that a concept similar to that discussed above has already been developed for nitric acid synthesis process based on boron nitride analogous to the Haber-Bosch route for nitric acid production from NH3. Finally, recent results have shown that unusual parallel behavior exists between hydrocarbons and their corresponding B-N analogues. Thus, hydrogenation of benzene to cyclohexane may also provide a model for the reformation of borazine to other amine-boranes. 

NO may decompose [Eq. (6.4.8)]. According to Figure 6.4.5, the equilibrium NO content in air is rather small below 3000 K. This is the reason why a high temperature was needed in the electric arc of the old Birkeland-Eyde process. Figure 6.4.5 also indicates that during combustion processes, for example, in a coal fired power plant, a content of NO of 1000 ppmv (0.1 vol. %) or more may be reached for temperatures above about 1500 K. In the case of nitric acid production from ammonia, NO decomposition must be avoided, and the product gas of NH3 oxidation is therefore rapidly quenched to below 700 K, where NO is metastable and decomposition is Idnetically hindered. 

Dual-Pressure Process. Dual-pressure processes have a medium pressure (ca 0.3—0.6 MPa) front end for ammonia oxidation and a high pressure (1.1—1.5 MPa) tail end for absorption. Some older plants still use atmospheric pressure for ammonia conversion. Compared to high monopressure plants, the lower oxidation pressure improves ammonia yield and catalyst performance. Platinum losses are significantiy lower and production mns are extended by a longer catalyst life. Reduced pressure also results in weaker nitric acid condensate from the cooler condenser, which helps to improve absorber performance. Due to the spHt in operating conditions, the dual-pressure process requires a specialized stainless steel NO compressor. 

It is available commercially from several routes including as a product from the manufacture of sodium nitrate from sodium chloride and nitric acid, and from a process involving the passage of ammonia and air over heated platinum and treating the nitric oxide so formed with oxygen. 

From the investigation into project feasibility, it is proposed to construct a plant that will deliver 280 tonnes per day of 60%(wt) nitric acid. This capacity is based on 8000 hours of operation per year, i.e. 330 days. It is envisaged that this nitric acid production facility will be centred within a larger chemical complex to be located in the Bunbury region of Western Australia. Other plants on this site will include an ammonia plant and an ammonium nitrate plant. Approximately 70% of the product acid will be consumed in situ for the production of crystalline ammonium nitrate. The remaining acid will be available to exploit the neighbouring South-east Asian export market. 

A few classicaV studies on the reactivity of HCs to reduce NOx with catalysts indicated that the use of such reductants for controlling mobile NOx emissions was quite attractive to the automotive industry, thereby the advent of a new type of HC-SCR technology in the mid-1980s. An example may be the treatment process of the tail gas from nitric acid production plant via ammonia oxida-tion. The process includes the usual injection of excessive amounts of HCs over supported noble metals such as Pt, Pd and Rh to eliminate the yellowish stack plume due to 0.1 - 0.5% NOx, mainly NO2, from the nitric acid plant. 

As a consequence of its recent development the petrochemical industry is relatively much younger than the major inorganic chemicals industry. However, one can easily be misled by the classification of products that are termed petrochemical . Basically a petrochemical is derived directly or indirectly from a petroleum or natural gas fraction. It may be organic, such as ethylene, benzene, or formaldehyde, or it may be inorganic, such as ammonia, nitric acid, and ammonium nitrate (Chap. 11). So a petrochemical is not synonymous with an organic chemical, although most petrochemicals are also organic chemicals. 

The Italian chemical journal, Rassegna Chemica 50), contains articles on technical and industrial developments and on chemical markets in Italy. Monthly statistics on Italian chemical production (quoted from the Ministry of Industry and Commerce) include the following synthetic ammonia, nitric acid, sulfuric acid, sodium carbonate, caustic soda, alumina, trichlorethylene, calcium carbide, carbon disulfide, explosives, superphosphates, ammonium sulfate, calcium cyanamide, calcium nitrate, ammonium nitrate, copper sulfate, dyestuffs, ethyl alcohol, methanol, tanning extracts, tartaric acid, citric acid, wood pulp and cellulose, and sodium nitrate. 

When a metal-catalyzed reaction is so fast that external mass transfer controls, several layers of fine wire screen can be used as the catalyst bed. The catalytic oxidation of ammonia to nitric oxide, which is the first step in nitric acid production, is carried out with screens (called gauzes) of Pt/Rh alloy, and very high ammonia conversions are obtained. Similar gauzes are used in the Andrussov process for manufacture of HCN from CH4, NH3, and O2. Wire screens are also used for catalytic incineration of pollutants and in improving combustion efficiency in gas burners. 

The major part of these catalytic processes is carried out in fixed bed reactors. Some of the main fixed bed catalytic processes are listed in Table 11.1-1. Except for the catalytic cracking of gas oil, which is carried out in a fluidized bed to enable the continuous regeneration of the catalyst, the main solid catalyzed processes of today s chemical and petroleum refining industry appear in Table 11.1-1. However, there are also fluidized bed alternatives for phthalic anhydride— and ethylene dichloride synthesis. Furthermore, Table 11.1-1 is limited to fixed bed processes with only one fluid phase trickle bed process (e.g., encountered in the hydrodesulfurization of heavier petroleum fractions) are not included in the present discussion. Finally, important processes like ammonia oxidation for nitric acid production or hydrogen cyanide synthesis, in which the catalyst is used in the form of a few layers of gauze are also omitted from Table 11.1-1. 

Fertilizer production was badly weakened by the dismantling of about 65% of the ammonia and 100% of the nitric acid capacities of the Leuna plants in Merseburg. The nitrogen plant Piesteritz also lost all of its facilities for nitric acid production, and the ammonia facility was removed from the Luetzkendorfer mineral oil plant. In addition, the phosphoric acid facility in Piesteritz (40,000 t per year) was completely dismantled and the older phosphoric furnaces in Bitterfeld were partly dismantled. 

The characteristics of the process wastewaters from the manufacture of plastic and synthetic materials are shown in Table 17. The plastic and synthetic materials industry is typically a continuous year-round operation. Because it is technically and economically advantageous, many hrms manufacture several different, but related chemical products at one location. For example, a typical complex makes ethylene, polyethylene, sulfuric acid, ethyl chloride, ammonia, nitric-acid and phosphoric acid. 

Nitridation usually occurs when carbon, low-alloy, and stainless steels are exposed to an ammonia-bearing environment at elevated temperatures. The production of ammonia, nitric acid, melamine, and nylon generate such conditions. Nitridation can also result from nitrogen atmospheres, especially under reducing conditions and high temperatures. There are many parallels to carburization nitridation occurs when chromium and other elements combine with nitrogen to form embrittling nitrides in the microstructure. 

It has been suggested that the practical similarities between methanol and ammonia oxidation led to the more rapid development of platinum gauzes for nitric acid production during the 1914-1918 war. Large-scale production of formaldehyde did not become important until the demand for phenol-formaldehyde plastics developed in the 1920s. With so little information available on the production of formaldehyde, it is more likely that the experience gained from ammonia oxidation in the wartime plants was then applied to the manufacture of formaldehyde. 

Adding nitric acid lowers the concentration of ammonia. Decreasing ammonia s concentration causes reaction 6.29 to move from products to reactants, decreasing the solubility of AgCl. 

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