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Chemicals from Non-hydrocarbons
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Nitric acid is commercially produced by oxidizing ammonia with air over a platinum-rhodium wire gauze. The following sequence represents the reactions occurring over the heterogeneous catalyst: 4NH3+5O2→4NO+6H2O2NO+O2→2NO23NO2+H2O→2HNO3+NO
Inorganic Chemical Pollutants
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Inhalation of high concentrations of ammonia causes temporary blindness and intolerable irritation of the eyes and the glottis. Large doses of ammonia can actually affect the cerebral energy metabolism in the brain.27 Smaller doses cause irritation of the respiratory tract and conjunctivae. The major hazard of ammonia is to office workers from blueprinting and copying machines, to workers in the chemical industry where larger amounts of ammonia are used in the chemical processes, and to farmers exposed to fertilizers. The TLV for ammonia is 25 ppm, corresponding to about 18 mg/m3.28 Again, this value is probably too high for chronic exposures. Excess ammonia can overload the oxidative deamination mechanisms and create chemical sensitivity, as has been seen in the patients at the EHC-Dallas, giving both reactive airway disease and cerebral dysfunction. The catalytic oxidation of ammonia with atmospheric oxygen gives oxides of nitrogen which can easily be converted to nitric acid (Figure 4.3).
Water Management
Published in L.B. (Bert) McCarty, Golf Turf Management, 2018
Safety. Citric acid, 75% phosphoric acid (H3PO4), and 35% sulfuric acid (H2SO4) are relatively safe to work with as compared to the 67% nitric acid (Table 8.21). Nitric acid is very caustic and can cause serious injury to exposed tissue, especially eyes and lungs. Avoid skin and eye exposure when handling any acid. Acid-resistant eyewear, gloves, and apron should be worn. Acids are corrosive and can damage clothing that is not immediately rinsed. Also, when mixing acid stock solutions, always add acid to a larger volume of water to create the stock. Never add water to concentrated acid.
Distribution and Statistical Analysis of Chemical Elements in Soil from the Territory of the Republic of Kosovo
Published in Soil and Sediment Contamination: An International Journal, 2023
Granit Kastrati, Ramë Vataj, Flamur Sopaj, Krste Tašev, Trajče Stafilov, Robert Šajn, Musaj Paçarizi
Samples from each individual soil depth in amounts of about 1 to 3 kg (0–5 cm and 20–30 cm) were stored in plastic bags, then cleaned of foreign matter, dried at room temperature, crushed, sieved through a 2 mm sieve, and grinded in an agate mill (Retsch PM 100 CM) and sieved onto a sieve of W = 125 microns, type Analysensieb DIN ISO 3310–1, stainless steel, to obtain particles below 0.125 mm. Then, samples were digested with acid mixture of HNO3, HClO4, HF and HCl in accordance with the international standards ISO 14,869–1:2001(E) (Stafilov et al. 2018). The digestion was performed in the following order: the accurately measured mass of dust samples (0.25 g) was placed in Teflon vessels. Then, 5 ml of concentrated HNO3 65% was added until brown vapors left the vessels. Nitric acid is a very suitable oxidizing agent for the digestion of organics in samples. For complete digestion of the inorganic components, 5–10 ml of HF (≥40%) was added. When the digestion became a clear solution, 1.5 ml of HClO4 70% was added for complete digestion of the organic matter. After cooling the vessels for 15 min, 2 ml of HCl 37% and 5 ml of water were added for the total dissolution of the metal ions. The obtained solution was filtered through Munktell filter paper No. 2, and the filtrate was leveled with redistilled water in a 25 ml volumetric plastic flask. The final sample was stored in plastic bottles labeled with the sample number and sent for analysis.
Experimental assessment of various fuel additives on the performance and emission characteristics of the spark ignition engine
Published in International Journal of Ambient Energy, 2022
T. Srinivas Rao, Sk. Jakeer Hussain, V. Dhana Raju, Harish Venu, Lingesan Subramani
Nitrogen oxide development fundamentally relies upon the availability of oxygen and higher temperature, while the combustion of air/fuel mixture in the combustion chamber. Figure 7 presents the deviation of emissions of nitrogen oxide for the used fuel samples in this investigation at different loads. The two common ingredients of nitrogen oxide (NOx) are nitrogen dioxide and nitric oxide. NOx is named as toxic and noxious gases for all the environment and human life. This nitrogen oxide is mainly responsible for many hazardous effects namely, smoke, acid rain followed by synthetic fog. From the figure, it is found that nitrogen oxide emissions are increased with the increment in engine load for the all tested fuel samples in this current investigation. The nitrogen oxide emissions for the used fuels of petrol, Ethanol 20%, Benzene 20% and Toluene 20% are 1450, 1350, 1390 and 1410 ppm, respectively, at full-load operation. The harmful exhaust emissions of NOX are decreased considerably with the addition of fuel additives than that of the pure gasoline.
Influence of ethanol-gasoline blended fuel on performance and emission characteristics of the test motorcycle engine
Published in Journal of the Air & Waste Management Association, 2022
Thanh Dinh Xuan, Dien Vu Minh, Binh Pham Hoa, Khanh Nguyen Duc, Vinh Nguyen Duy
NOx is a nitrogen oxide combination that includes a minor amount of other nitrogen oxides, nitric oxide, and nitrogen dioxide. It is affected by the air-fuel ratio, combustion chamber temperatures, and engine operating conditions. NOx is formed due to the thermal NOx, fuel NOx, and N2O intermediate processes. Figure 5 depicts the nitrogen oxides (NOx) emissions measured at different engine speeds. NOx emissions rose with increasing load and speed for all of the test fuels. The highest average emission of NOx corresponding to the test vehicle running on E20, E10, and E5 was respectively 67%, 47%, and 37% higher than that of E0. This trend shows that the higher the alcohol percentage in the blend, the more NOx the fuel produces. The resultant nitrogen oxides are produced in the atmosphere from nitrogen and oxygen, and the temperature is the most significant component influencing the formation. Thermal NOx generation is also a substantial process in ethanol-gasoline mixtures. The lower heating value and high ethanol heat reduce temperature, resulting in a temperature drop in the cylinder. NOx production is reduced when the adiabatic flame temperature is low. More fuel is used in this research realized at stoichiometry because of rising volumetric efficiency owing to stoichiometric rate reduction parallel with increasing ethanol rate, high vapor density, and evaporation heat.