The formation of carcinogenic N-nitrosamines from reactions between solvent amines and flue gas NOx is an important concern for the application of amine-based processes to capture CO2 post-combustion. Using an advanced test rig with interconnected absorber and desorber units, we evaluated the importance for N-nitrosamine formation of the desorber relative to the absorber, and any synergism between the two units. Variations in desorber temperature and in flue gas composition indicated that N-nitrosamine formation from fresh monoethanolamine (MEA) occurred predominantly in the absorber. N-nitrosamine formation was driven by high NO2 and O2 flue gas concentrations, although NO also contributed. In contrast, N-nitrosamine formation from piperazine (PZ) was driven by reactions with nitrite in the heated desorber, and accelerated concurrent with nitrite accumulation. A complementary experiment simulating aged MEA solvent (high nitrite, 1.5 % sarcosine as a proxy of secondary amine degradation products) suggested the desorber becomes an order of magnitude more important than the absorber for N-nitrosamine formation. For fresh MEA solvent, increasing the desorber temperature from 110 °C to 130 °C promoted thermal decomposition of N-nitrosamines, reducing N-nitrosamine accumulation rates two-fold. Compared to the test rig, the prevailing practice of using separate absorber columns and autoclave-like treatments to mimic desorber units predicted the direction, but underestimated the magnitude of N-nitrosamine formation. Because N-nitro...
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Round-ups are the summaries of handpicked papers around trending topics published every week. These would enable you to scan through a collection of papers and decide if the paper is relevant to you before actually investing time into reading it.
Coronavirus Research Articles published between Oct 11, 2021 to Oct 17, 2021
Oct 18, 2021
Articles Included: 3
Muhammad Ikbal and colleagues (2021) reported in ‘Visualisasi dan Analisa Data Penyebaran Covid-19 dengan Metode Klasifikasi Naïve Bayes’ that the cov...Read More
Climate change Research Articles published between Oct 11, 2021 to Oct 17, 2021
Oct 18, 2021
Articles Included: 5
Junjie Jia et al. (2021) reported in ‘Driving mechanisms of gross primary productivity geographical patterns for Qinghai–Tibet Plateau lake systems’ t...Read More