China
Africa
Explore chapters and articles related to this topic
The Chemistry of Hazardous Materials
Published in Armen S. Casparian, Gergely Sirokman, Ann O. Omollo, Rapid Review of Chemistry for the Life Sciences and Engineering, 2021
Armen S. Casparian, Gergely Sirokman, Ann O. Omollo
Chlorine and ammonia may also react directly to form compounds, with or without the presence of water, which are particularly hazardous to health. Gaseous ammonia and chlorine can react to produce ammonium chloride, NH4Cl, and chloramine, NH2Cl. Regardless of the pathway, NH2Cl is a very toxic gas, which can lead to suffocation or asphyxia. Di- and trichloroamines, NHCl2 and NCl3, may also be formed by autocatalytic reaction or consecutive reactions and are equally hazardous.
Particulate matter
Published in Abhishek Tiwary, Ian Williams, Air Pollution, 2018
The ammonium nitrate and ammonium chloride particles are generated by corresponding reactions between gaseous ammonia and nitric acid vapour or hydrogen chloride, respectively. Long-term records of suspended particulate show that European sulphate concentrations rose slowly but steadily from the 1950s, peaked in the late 1970s and have since declined. This pattern reflects the improved control of SO2 emissions over the same period. Particulate nitrate, on the other hand, has continued to increase, although concentrations are expected to fall again as vehicle NOx emissions decline. On a larger scale, measurements from the European Monitoring and Evaluation Programme (EMEP) network have shown a gradient of particulate sulphate concentration from peak values in south-east Europe of around 3 μg S m−3, through about 1.5 μg S m−3 down to around 0.5 μg S m−3 in Scotland. This sulphate probably contributes about 6 μg m−3 to the background PM10 concentration in both rural and urban areas of southern Britain, and about one-third of that in the north. The corresponding values for nitrate PM10 would be about two-thirds of these figures. Hence, in industrial countries that also have intensive animal husbandry and/or crop production, a characteristic haze of fine particles is produced. The long range import of secondary particles can also make it hard to achieve standards for PM10 concentration.
Postcombustion NOx Control
Published in David A. Lewandowski, Design of Thermal Oxidation Systems for Volatile Organic Compounds, 2017
When hydrogen chloride (HCl) is a product of the thermal oxidation reaction, this HCl will react with ammonia to form ammonium chloride. Ammonium chloride is a white, crystalline solid that is water soluble, hygroscopic, and corrosive. If present in a significant concentration, it will form a detached, white plume in the stack exhaust. An opacity monitor will not detect this plume.
Contribution of tailpipe and non-tailpipe traffic sources to quasi-ultrafine, fine and coarse particulate matter in southern California
Published in Journal of the Air & Waste Management Association, 2021
Rima Habre, Mariam Girguis, Robert Urman, Scott Fruin, Fred Lurmann, Martin Shafer, Patrick Gorski, Meredith Franklin, Rob McConnell, Ed Avol, Frank Gilliland
In the PM2.5 size fraction, seven source factors were resolved as follows: “Ammonium Sulfates” with high loadings of La and S, possibly related to secondary formation from petroleum refineries and industrial emissions (Kulkarni, Chellam, and Fraser 2007). It contributed 22.8% of the total PM2.5 mass. Two tailpipe traffic sources were identified in PM2.5 – “Traffic (gasoline)” with loadings of wsOC, isOC and B (15% of the mass) and “Traffic (diesel)” with loadings of EC and barium (Ba) (5.9% of the mass). “Traffic (gasoline)” was elevated in most communities with major freeways (SB, ML, SD, UP) while “Traffic (diesel)” was elevated in communities with truck activity (LB, AN, SD, GL). “Sea Salt” also contributed 15.9% of PM2.5 mass, with loadings of Na, Cl and Mg, and highest contributions in the coastal community of SB. “Abrasive Vehicular Emissions” (AVE) was also resolved, with an 11.4% contribution to mass and high loadings of Ag, Mo, Zn, Ni, V, Pt and Rh. This factor was highest in communities with significant truck and freight activity (LB, ML, AN), and the presence of Ni and V here suggests a certain degree of collinearity with fuel oil sources originating from source areas in close proximity (i.e., the ports) (Habre, Coull, and Koutrakis 2011). “Crustal” (19% of PM2.5 mass) was also resolved with Al, Dy and Fe – elements related to soil – and highest contributions in the inland, arid community of ML with agricultural and dairy production. Finally, a factor related to secondary inorganic PM formation was identified with high loadings of ammonium, nitrate and chloride (“Ammonium Nitrate/Ammonium Chloride”). It contributed ~10% of PM2.5 mass and had highest contributions in the cool season in RV (Figure 8). This is a result of ammonia (NH3) reactions with nitric and hydrochloric acid, which is shown to favor formation of ammonium nitrate and ammonium chloride especially in cold conditions (Kelly et al. 2013; Wang et al. 2015).