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Two of the main challenges in post-combustion CO2 capture with ethanolamine are solvent degradation and material corrosion. It has been shown that there is a correlation between degradation and corrosion. The present paper examines this correlation by studying the effect of 10 MEA degradation products on corrosion. Thermal degradation experiments were conducted under stripper conditions for 5 weeks. 30wt% MEA solution with 1wt% of the various degradation products were placed in 316 SS cylinders and stored in a thermostat chamber at 135 °C. ICP-MS was used for the metal concentration analyses for all the solutions, while ion chromatography was used for the quantitative determination of heat stable salts anions and MEA concentrations. The solutions were also analyzed for degradation products in order to study the formation and thermal stability of these compounds. For corrosion monitoring, in addition to ICP-MS analyses, SEM-EDS was used for examining the cylinders surface morphology and elemental composition while XRD was used for corrosion product identification. In the present paper, the influence of the secondary degradation products on corrosion is studied. Results show that some specific degradation products, like bicine, HeGly and HEEDA enhance corrosion while others don't seem to have a significant effect on corrosion of stainless steel.

Hydrogels show great promise in cell-based tissue engineering, however new fabrication and modification methods are needed to realize the full potential of hydrogel based materials. The inclusion of an inorganic phase is one such approach and is known to affect both cell-material interactions and mechanical properties. This article describes the development of a correlative experimental approach where gel formation and mineralization has been investigated with spatial and temporal resolution by applying Raman microspectroscopy, optical and electron microscopy and a reaction-diffusion modeling scheme. Modeling allows us to predict gelling kinetics for other geometries and sizes than those investigated experimentally. Our experimental system enables non-destructive study of composite hydrogel systems relevant for, but not limited to, applications within bone tissue engineering.

The precipitation and transformations of calcium phosphates (CaP) is a complex process, where both formation kinetics and the stability of different mineral phases control the outcome. This situation is even more complex if CaP is precipitated in a hydrogel matrix, where one can expect the organic matrix to modulate crystallization by introducing supersaturation gradients or changing the nucleation and growth kinetics of crystals. In this study we apply a range of characterization techniques to study the mineral formation and transformations of CaP within an alginate matrix with spatiotemporal resolution. It demonstrates how a detailed investigation of the mineral precipitation and transformations can aid in the future rational design of hydrogel-based materials for bone tissue engineering and studies of biomineralization processes.

Use of scaffolds both as supporting materials at defect site and delivery vehicles for bioactive agents is a commonly employed strategy to aid in tissue repair and regeneration. In this study, fibrous meshes of chitosan were prepared by wet spinning and coated with alginate. BSA as a model protein and gentamicin as a model antibiotic were incorporated into the scaffolds in multiple loading models and their release kinetics were studied. The effects of structural form of scaffold and properties of bioactive agents on release profiles were evaluated. Our results suggest that, designed scaffolds are potential candidates for tissue engineering with the feature of controlled bioactive agent delivery.