Monoethanolamine degradation

Monoethanolamine Systems. Monoethanolamine (MEA) is a primary amine that can meet nominal pipeline specifications for removing both H2S and CO 2. MEA is a stable compound and in the absence of other chemicals suffers no degradation or decomposition at temperatures up to its normal boiling point. MEA reacts with CO2 and HiS as follows ... 

HPCA is degradable by chlorine and so it is usual to include a small amount of monoethanolamine (MEA) in the formulation to improve the resistance of this inhibitor to oxidation. 

Finding Based on available data and the experience of the members of the committee, the chemical constituents most likely to be of concern in the RAP process for EDS liqnid wastes are chlorinated organics, possible degradation products of energetic compounds, metals, suspended solids, and monoethanolamine (MEA). These constituents were chosen based on their abundance in the neutralent, their inherent toxicity, their resistance to treatment, or overall regulatory and public concern. 

Absorption is a process that relies on a solvent s chemical affinity with a solute to dissolve preferably one species into another. It is widely proposed for CO2 separation where a solvent, generally, monoethanolamine (MEA) or a solid absorbent like lithium zirconate is used to dissolve CO2, but not the other components of a flue gas stream. C02-rich solution is typically pumped to a regeneration column, where CO2 is stripped out from the solution and the solvent recycled for a new batch of flue gas. The absorption equipment should be placed after the flue gas desulfurization-step and before the stack. Optimal conditions for absorption are low temperature and high pressure, making this the best location for absorption to occur. In addition, most solvents are easily degraded by compounds such as fly ash, other particulates, 80, (SO2, SO3) and (NO, NO2), so the absorption step must take place after electrostatic precipitation and desulfurization. In a typical absorption process, the C02-lean flue gas is either emitted to the atmosphere or possibly used in other applications e.g. chemical production). 

Irreversible Reaction of Monoethanolamine (MEA) with CO. Polderman et al. (1955A, B) first investigated the reaction of CO2 with monoetiianolamine to fcNtm amine degradation products. The reaction mechanism proposed by Polderman et aL (1955A, B) is essentially identical to that proposed later by Kim and Sarttm (1984) for DEA and by Kim (1988) for DIPA. The reactions begin with the formation of the carbamate ion ... 

As shown by Kim and Sartori (1984), the irreversible reactions of dietiumolamine with CO2 are analogous to the reactions of monoethanolamine. The degradation reactions are probably initiated by the formation of the carbamate ion ... 

Systems handling mixtures of the two fall between these two extremes if the gases contain at least 1 vol.% H2S. Corrosion in amine plants using monoethanolamine is more severe than in those using diethanolamine, because the former is more prone to degradation. Corrosion is not caused by the amine itself, but is caused by dissolved hydrogen sulfide or carhon dioxide and by amine degradation products. 

Corrosion and other operational problems can be greatly reduced by proper plant operation. It is recommended that the gas loading (ratio of moles of acid gases to moles of MEA) be kept to 0.45 or less, monoethanolamine concentration be kept at 20%, and that degradation products be removed by use of a side-stream reclaimer. 

In [74], a method of reclaiming of PUR flexible foam waste by grinding of foam scraps and heating in the presence of mono- and diethanolamine at a temperature of 130-150°C is described. The reaction process was considerably faster when monoethanolamine was used at elevated temperature. After the completion of the process, the degradation product underwent separation into... 

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