Risk evaluation of decomposition of hydroxylamine/water solution at various concentrations

Abstract

The thermal property of HA/water solution was studied from the calorimetric data obtained using differential thermal analysis (DTA). The intensity of decomposition was studied from results of a mini closed pressure vessel test (MCPVT), and a pressure vessel test (PVT), in addition to the steel tube test. The thermal analysis was conducted to evaluate the ease of thermal decomposition using DTA. The heat‐release onset temperatures using the no‐treated stainless steel cells were more than 70° C below those measured using the gold‐coated stainless steel cells. This result implies that the heat‐release onset temperature depends on the materials of the sample cell. The intensity of the thermal decomposition was investigated using the MCPVT, the PVT, and the steel tube test. The intensity of the thermal decomposition increased as the HA concentration increased in the MCPVT. The intensity of the thermal decomposition increased greatly when the HA concentration was beyond 80% (wt.) in the MCPVT. It was determined that the thermal decomposit ion of HA 70%/water solutions was very violent in the PVT. In addition, HA/water solutions of more than 80% concentration could detonate in the steel tube test.

Approaching Bulk Chemical Nitriles from Alkenes: A Hydrogen Cyanide-Free Approach through a Combination of Hydroformylation and Biocatalysis

“…The decomposition of hydroxylamine in aqueous solution at an elevated temperature is described in the literature to proceed under formation of ammonia, nitrites, and nitrates . However, it should be added that such a procedure has to be taken with high caution as in general thermal decomposition of hydroxylamine raises safety concerns since hydroxylamine has turned out to be a chemically instable compound, which also has led to tragic incidents in industry . Thus, we only utilized this thermal decomposition method to remove trace amounts of hydroxylamine present in highly diluted concentration in an aqueous medium.…”

Do-It-Yourself: Differential Scanning Calorimetry Glass Capillary Crucible for Thermal Safety Evaluation of a Chemical Process

“…Iwata and Koseki have reported that thermal decomposition of 50% hydroxylamine aqueous solution was remarkably accelerated due to a catalytic effect of the stainless steel surface of a SS crucible, based on comparative differential thermal analysis (DTA) measurements between a gold-plated crucible and a SS crucible . The decomposition onset temperatures were observed at about 75 °C for the SS crucible and about 130 °C for the gold-plated crucible.…”

Initial Decomposition Pathways of Aqueous Hydroxylamine Solutions

“…Numerous studies have been conducted involving calorimetric and explosion hazard assessments of aqueous HA solutions, − and some reasonable reaction mechanisms have been developed. − HA in the free base form has been shown to decompose at high temperatures according to reactions and , below, which respectively account for five and two-sevenths of the total decomposition. , …”