Amine Composition Research Articles

Research Process on Water Treatment Agent of Boiler for Preventing Metal Corrosion in the Steam-water Cycle

The safe and economical operation of boiler is influenced significantly by the metal corrosion in the steam-water cycle. It is the most common way to add the water treatment agents into the boiler water to prevent metal corrosion. In this paper, the application situation and limitations of the traditional boiler water treatment agents were summarized. Then the research process of the film-forming amines was elaborated. First, the structure and composition of film-forming amines, their properties and the interaction mechanisms with metal materials were described. Second, the industrial application of the film-forming amines was considered. Third, the existing problems of film-forming amines were discussed. Finally the future development of the novel film-forming amines was prospected.

Development and thermal behavior of a new type of polymer materials with reduced combustibility based on epoxy–amine composites modified with copper(II) hexafluorosilicate

The polyamine chelate complex of copper(II) hexafluorosilicate—[Cu(eda)(deta)]SiF6—(a flame retardant-hardener of epoxy resins) and CuSiF6-containing epoxy–amine composites—DGEBA/pepa-CuSiF6—with reduced combustibility and with the varied content of CuSiF6 were obtained in the DGEBA–pepa–CuSiF6 system (pepa—H2N[–C2H4NH–]nH, n = 1 (eda—NH2C2H4NH2) and n = 2 (deta—NH2C2H4NHC2H4NH2); DGEBA—bisphenol A diglycidyl ether). These samples were characterized by IR spectra, thermal analysis and flammability studies. The results of Thermogravimetric analysis (TGA) showed that thermal decomposition of [Cu(eda)(deta)]SiF6 is completed at 368 °C and the maximal temperature of the gaseous combustion products was 488 °C. TGA data for DGEBA/pepa-CuSiF6(22) confirm that the incorporation of [Cu(eda)(deta)]SiF6 into DGEBA significantly increases thermal stability and anti-flammability of CuSiF6-containing epoxy–amine composites. Ignition and self-ignition temperatures have been measured for all CuSiF6-containing epoxy–amine composites in accordance with ASTM D1929-16. Depending on the quantity of added CuSiF6, the tignition for this type of composite increases by 15–34 °C, and the tself-ignition increases by 25–58 °C compared to DGEBA/pepa. The flammability of the samples was evaluated by means of UL94 BH methods. The burning rate of the DGEBA/pepa-CuSiF6(66) and DGEBA/pepa-CuSiF6(88) epoxy–amine composites is severe slowed down (these samples do not propagate flame), while rburn. value for the unmodified epoxy–amine sample (DGEBA/pepa) is 25.13 mm min−1.

Residual chemical analysis of amines used as corrosion inhibitors

Main problem: Presence of acidic chemicals such as carbon dioxide and hydrogen sulphide, composition of production fluids triggers corrosion. Corrosion in oil and gas industry leads to deterioration of equipment since most of equipment is made of metal alloys. Application of inhibitors is one of the corrosion mitigation methods that needs to be controlled because it is important to identify optimal concentration of the chemicals in production fluids.Residual chemical analysis plays an important rolein identifying the appropriate dosage of corrosion inhibitors and its correction. It is imperative to find the most optimal concentration of amines due to the fact that both overdose and underdose could lead to equipment deterioration. The chemical analysis is hindered by complexity of mixtures that are applied in petroleum industry. Purpose: The main purpose of this article is to find out the most effective method of residual chemical analysis for inhibitors used against sweet and sour corrosion by studying and analyzing corresponding literature review. The analysis should be carried out with robust, sensitive, and accurate instrumentation. Methods :Theoretical study of composition and mechanism of amines used in oil and gas industry as corrosion inhibitors and selection of appropriate instrumental analytical techniques for the residual analysis. Results and their importance: After careful studying and consideration of modern instrumental analytical techniques the most optimal and efficient method in terms of robustness, time saving and cost was selected. Ion chromatography is an adequate method to carry out residual chemical analysis for amines that are used as inhibitors in oil and gas industry to prevent sweet and sour corrosion.

Novel CuSiF6-coordinated epoxy–amine composites with reduced combustibility: Elaboration, thermal-oxidative behavior, and ignition susceptibility

In the DGEBA–PEPA–CuSiF6 system (DGEBA is diglycidyl ether of bisphenol A, PEPA is polyethylenepolyamine), a new flame-retardant hardener for epoxy resins in the form of a chelate complex labeled as PEPA–CuSiF6 was synthesized and incorporated into the framework of DGEBA to make a range of CuSiF6-containing epoxy–amine composites (EA–CuSiF6) with reduced combustibility. The resulting EA–CuSiF6 composites were characterized using FTIR spectroscopy, thermogravimetric analysis (TGA), and temperatures of ignition and self-ignition measuring. TGA results showed that the thermal decomposition of PEPA–CuSiF6 ends at 368 °C, and after ignition of its organic component, the maximum temperature of the gaseous products of combustion reached 488 °C. TGA of EA–CuSiF6(22) sample confirms that the incorporation of PEPA–CuSiF6 into DGEBA significantly increases the thermal stability and reduces the flammability of the epoxy–amine composites. The combustibility of the epoxy–amine composite samples was investigated using “Ceramic tube” (CT) method. Results of CT measurement reveal that the maximal temperature of combustion gases for EA–CuSiF6(66) in comparison with unmodified epoxy–amine polymer (EAP) appreciably goes down and relative loss of the mass lessens. The measured ignition and self-ignition temperatures showed that depending on the amount of CuSiF6 added, tignition and tself-ignition for this type of composites increase by 15–34 °C and 25–58 °C, respectively, compared to EAP that does not contain additives.

Surface Curvature and Aminated Side-Chain Partitioning Affect Structure of Poly(oxonorbornenes) Attached to Planar Surfaces and Nanoparticles of Gold.

Cationic amphiphilic polymers are often used to coat nanoparticles as they increase chemical stability in solution and exhibit membrane disruption activities. Among these, poly(oxonorbornenes) (PONs) are tunable membrane disruptors. They can be constructed with either one amine-terminated side chain and one hydrophobic alkyl side chain (PON-50) or two amine-terminated side chains (PON-100) on each repeat unit and can then be conjugated to gold nanoparticles using O-(2-carboxyethyl)-O'-(2-mercaptoethyl) heptaethylene glycol (HEG) spacers. While the amine content and membrane disruption activity of PONs can be controlled, the detailed structural properties of PONs conjugated to gold nanoparticles remain less understood. To address this, we performed molecular dynamics simulations of PON-50 and PON-100 to determine the nonbonded energies of PON structures as a function of amine composition. We found increasing energetic stabilization with decreasing amine composition. These results were consistent with experimental observations obtained with X-ray photoelectron spectroscopy (XPS) in which PON-100 was found to have the lowest conjugation efficiency to gold surfaces out of a range of PON amination ratios. Computationally obtained energetics suggest that replacing the aliphatic amine groups with aromatic amine groups can reverse this behavior and lead to more stable PON structures with increasing amine content. We also found that the curvature of the gold nanoparticle surface affects interactions between the surface and the amine groups of PON-50. Increasing curvature decreased these interactions, resulting in a smaller effective footprint of the HEG-PON-50 structure.

Evaluating the influence of simultaneous inoculation of SiO2-alginate encapsulated bacteria and yeasts on volatiles, amino acids, biogenic amines and sensory profile of red wine with lysozyme addition

The influence of the timing of inoculation (sequential and simultaneous alcoholic fermentation (AF)/malolactic fermentation (MLF)) on the chemical and sensory properties of red wines was studied. The impact of the encapsulation of Oenococcus oeni into SiO2-alginate hydrogel (Si-ALG) and the addition of lysozyme in wines inoculated with encapsulated bacteria were also analysed. There was a significant influence of the timing of inoculation on the volatile composition of the wines just as on the amino acid and biogenic amine content. The wines produced by simultaneous AF/MLF showed the highest contents of some volatile compounds, such as ethyl esters and terpenes, as well as amino acids and tyramine. Bacterial encapsulation affected the volatile and amino acid profile of the wines, while the biogenic amine composition was not modified. The chemical composition of the wines was not altered by the presence of lysozyme. A trained panel did not perceive substantial differences between treatments.

Global and local conductivity in percolating crosslinked carbon black/epoxy\u2013amine composites

Conductive particle-filled polymer composites are promising materials for applications where both the merits of polymer and conductivity are required. The electrical properties of such composites are controlled by the particle percolation network present in the polymeric matrix. In this study, the electrical properties of crosslinked carbon black–epoxy–amine (CB-EA) composites with various CB concentrations are studied at room temperature as a function of the AC frequency f. A transition at critical frequency fc from the DC plateau σDC to a frequency-dependent part was observed. Conductivity mechanisms for f > fc and f < fc were investigated. By considering the fractal nature, conduction for f > fc was verified to be intra-cluster charge diffusion. For f < fc, with the assistance of conductive atomic force microscopy (C-AFM), the conduction behavior of individual clusters can be observed, revealing both linear and nonlinear I–V characteristics. By combining microtoming and C-AFM measurements, 3D reconstructed images offer direct evidence that the percolating network of these materials consists of both a low-conductivity part, in which the charge transports through tunneling, and a high-conductivity part, which shows ohmic electrical properties. Nevertheless, for these CB-EA composites, the presence of these non-ohmic contacts still leads to Arrhenius-type behavior for the macroscopic conductivity.

LC‐MS Fingerprinting Method for the Trace Amines Ratio and Synephrine Enantiomers Found in Citrus Aurantium‐Listing Pre‐Workout Supplements

Background/AimThe popularity of weight‐loss and pre‐workout supplements (PWS) has been associated with adverse cardiovascular effects. Since 2004, bitter orange (Citrus aurantium) extracts were listed as a natural stimulant in these supplements. Bitter orange is known to contain the sympathomimetics, p‐synephrine, p‐octopamine and p‐tyramine. However, the origin of these amines is questionable due to discrepancies between the labelled and actual content found in previous analytical methods. This study aimed to produce an LC‐MS fingerprint profile for the three amines and enantiomeric ratios of p‐(±)‐synephrine in standardized reference materials (SRMs) to compare to PWS.MethodsThree SRMs and fifteen bitter orange‐listing PWS were analyzed under two reversed‐phase LC‐QDa‐MS chromatographic separation protocols. Quantitative method used an XBridge BEH C18 (100mm x 4.6mm, 2.5μm) with a mobile phase of water (A) and acetonitrile (B), both with ammonium carbonate buffer (pH 10.0; 5mM), under gradient conditions (1–45 %B over 10 minutes) at a flow rate of 0.8mL/min and UV detection at 242 nm. Quantifications were based on the racemic amine standards. Qualitative enantiomeric separations were conducted using a Chiral‐CBH column (100mm x 4.0mm, 5μm) under isocratic conditions with a mobile phase of methanol (15%, w/w) in ammonium acetate buffer (pH 7.0, 5mM) and a flow rate of 0.6 mL/min. UV detection was at 225nm. A QDa mass detector provided structural confirmation in ESI+ mode.ResultsTrace amines and enantiomeric ratios of the SRMs support the current literature where (−)‐synephrine was the main amine of bitter orange, whereas octopamine, tyramine and (+)‐synephrine were present in low concentrations. Quantitative methods were linear over a 1.0 – 250 μg/mL range. The limit of quantification (LoQ) for amines was 0.45 μg/mL. Synephrine was detected in the majority of supplements (11/15; 0.025mg – 38.8 mg/serve) whereas octopamine was only in 5/15 (0.013 mg – 0.54 mg/serve) and tyramine in 8/15 supplements (0.017 mg – 0.43 mg/serve). Only 3/15 PWS had trace amine ratios (octopamine: synephrine: tyramine) similar to that found in the plant SRMs. The enantiomeric separation was linear, ranging from 0.5 – 200 μg/mL. LoQ was 1.75 μg/mL for (−)‐synephrine and 1.62 μg/mL for (+)‐synephrine. Only 5/15 supplements showed similar enantiomeric ratios to that of the SRMs, 4/15 supplements showed racemic synephrine profiles while 2/15 supplements showed higher amounts of (+)‐synephrine.ConclusionThis pilot study incorporated bitter orange SRMs to quantify and then establish a relative ratio for the trace amines, synephrine, octopamine and tyramine, as well as determine enantiomeric ratios for p‐synephrine. Only 3/15 PWS contained a matching profile of trace amines and an enantiomer ratio suggestive of natural origin. Furthermore, the amounts of (+)‐synephrine suggest that synephrine had been added synthetically or undergone racemization during manufacture. Variability of trace amine composition in PWS presents increased risks to consumers, especially when supplements often contain a cocktail of stimulants, including caffeine and other plant extracts.Support or Funding InformationResearch was supported by an Australian Government Research Training Program ScholarshipRepresentative summary of the two LC‐MS methods to quantify and qualify trace amines in standardized bitter orange extract and pre‐workout supplements that had natural, racemic and synthetic profiles. Top row: Representative peaks of synephrine (Syn; green), octopamine (Oct; red) and tyramine (Tyr; blue). Bottom row: representative peaks of (±)‐synephrine enantiomers.Figure 1

Behavior and mechanism of graphene oxide-tris(4-aminophenyl)amine composites in adsorption of rare earth elements

Three-dimensional (3D) graphene oxide-tris(4-aminophenyl)amine (GO-TAPAx:y) composites with different GO-to-TAPA mass ratios (x:y) were prepared by a facile one-step ultrasonic treatment. GO-TAPAx:y composites were characterized by scanning electron microscopy (SEM), nitrogen (N2) adsorption-desorption isotherms, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). Behavior and mechanism of GO-TAPAx:y composites for the adsorption of rare earth elements (REEs) were investigated. The adsorption capacities of GO-TAPA1:2 composite for Yb3+, Er3+, Nd3+, La3+ and Y3+ are 30.88, 26.52, 20.60, 11.24 and 10.52 mg/g, respectively. Effects of some important parameters including GO-to-TAPA mass ratios, contact time, reaction temperature and initial Yb3+ concentration on the adsorption were evaluated in detail. FTIR spectral and XPS analyses show that the metal complexations and ion exchanges between nitrogen/oxygen-containing species of the adsorbents and REEs are involved in the adsorption procedure besides the conventional adsorption based on specific surface area, indicating the introduction of specific molecules onto GO is beneficial to its adsorption ability. The convenient reusability and applicability of GO-TAPAx:y composites toward real samples also demonstrate their feasibility in the enrichment of REE ions.

Rapid synthesis of solid amine composites based on short mesochannel SBA-15 for CO2 capture

Hydrothermal is common process for synthesizing well-ordered mesoporous silica, however, it costs time and energy simultaneously. To improve the efficiency of synthesis process, it is necessary to propose a facile synthesis strategy with less time and energy requirement. In this study, an innovative non-hydrothermal method using NH3∙H2O as catalyst after ripening step is developed to prepare SBA-15 with short mesochannels (SSBA-15) for the first time. The synthesis period of SSBA-15 framework was extremely shortened within 40 min under the optimized conditions (30 min of ripening step and 25% of NH3∙H2O concentration), while obtained material exhibits well-ordered hexagonal pore structure and fine particle morphology of SSBA-15 (pore length of 250 ± 50 nm and mesopore size of 9.8 nm). This method can also be employed to synthesize conventional SBA-15 successfully. Moreover, the application of SSBA-15 as support of solid amine adsorbents on CO2 adsorption and well-fitting of experimental CO2 adsorption data with Avrami and intraparticle diffusion models reveal that the adsorbents combine the advantages of micro-mesoporous structure, short mesochannel and amine reagents (high affinity of CO2), resulting in enhanced molecular diffusion, fast adsorption kinetics and high CO2 adsorption capacity. Notably, the solid amine adsorbents exhibited excellent regeneration ability during ten adsorption-desorption cycles. This work opens up new opportunities in efficient preparation of materials that require hydrothermal process.

Silica supported poly(propylene guanidine) as a CO2 sorbent in simulated flue gas and direct air capture

A guanidine-based oligomer/polymer, poly(propylene guanidine) (PPG), is synthesized and impregnated into mesoporous silica, SBA-15, to prepare a composite organic/inorganic CO2 sorbent. 1H NMR and ESI-TOF MS spectra are used to characterize the structure of the synthesized oligomer/polymer. The adsorption capacities of the PPG based sorbents are measured under both simulated flue gas conditions and direct air capture conditions, and are compared to the performance of poly(ethylene imine) (PEI) based sorbents, the current state of art material among supported amine compositions. While PPG sorbents show lower pseudo-equilibrium capacities than PEI based sorbents under 400 ppm CO2 flow, they show comparable adsorption capacities using 10% CO2 streams. Furthermore, PPG sorbents were able to reach their pseudo-equilibrium capacity in a shorter time than the PEI sorbents under both 10% and 400 ppm CO2. However, due to the higher volatility of the prepared oligomeric PPG, the PPG sorbents show a fast decrease in the adsorption capacity when used over multiple cycles, suggesting that improved performance may be obtained using higher molecular weight oligomers/polymers.

Zeolitic imidazolate framework promoters in one-pot epoxy–amine reaction

Epoxy composites are widely used in commercial products. For industrial purposes, storage stability is one of their most important characteristics. To enable this feature, alternative promoters that are stable at a low-energy state, where they do not react, are needed. Zeolitic imidazolate frameworks (ZIFs) are organic–inorganic complexes, and they contain imidazolate linkers, which are one of the promoters in the epoxy–amine reaction. In this study, the stability of a one-pot epoxy–amine composite was improved by using ZIFs as promoters. ZIFs were synthesized using the solvothermal method, and their structure were confirmed using X-ray diffraction analysis and field-emission scanning electron microscopy. The activation energy of the ZIFs was measured using the non-isothermal method of differential scanning calorimetry, and it was calculated using the Kissinger equation. Furthermore, the storage stability of the one-pot epoxy–amine system was measured considering the viscosity change with time at constant temperature. The viscoelastic behavior of the cured sample was demonstrated using dynamic mechanical analysis.

Использование микробных культур в технологии функциональных напитков

Чай является традиционным напитком для многих народов мира. В странах Востока помимо традиционных видов чая использовали напитки, полученные микробной ферментацией листьев чайного растения. Примером является китайский чай Хэй Ча и напиток, полученный ферментацией чайного экстракта – Комбуча. Микробные культуры, используемые для ферментации, придавали напиткам дополнительные функциональные свойства. Целью данного исследования было изучение микроскопических грибов, используемых в технологии чая Хэй Ча, и ассоциации бактерий и дрожжей напитка Комбуча с последующим изучением возможности их использования для получения ферментированных напитков. Из образцов чая Хэй Ча были выделены микроскопические грибы, идентифицированные как E. cristatum, из напитка Комбуча – бактерии рода Acetobacter и дрожжи рода Saccharomyces. Изучено влияние состава ферментированного сырья и режимов культивирования на рост и развитие выделенных микроорганизмов. Определенны оптимальные параметры ферментации и разработана технологическая схема получения готового ферментированного продукта на основе Chamaenerion angustifolium (кипрей узколистный). Показано, что используемые микроорганизмы не синтезируют микотоксины, обладают способностью к синтезу антиоксидантов и витаминов группы В и др. В напитках, полученных ферментацией экстрактов листьев Camellia sinensis (камелий китайская), Chamaenerion angustifolium (кипрей узколистный) было определенно содержание и состав биогенных аминов, аминокислот, фенольных соединений и антиоксидантов. Разработана рецептура напитков с использованием выделенных микробных культур, в состав которых в качестве дополнительных ингредиентов входят мёд, солодовое сусло, сок виноградный, мате, кофе. Безопасность продукта была подтверждена результатами микробиологического анализа. Полученные напитки имеют насыщенный цвет, приятный аромат, кисло-сладкий с фруктовыми оттенками вкус.

Effect of Lactobacillus acidophilus, Oenococcus oeni, and Lactobacillus brevis on Composition of Bog Bilberry Juice.

This study investigated the impact of Lactobacillus acidophilus NCFM, Oenococcus oeni Viniflora® Oenos and Lactobacillus brevis CICC 6239 on bog bilberry juice with a considerably low pH and rich in anthocyanins content. Moreover, the effects of the strains on the composition of phenolic compounds, amino acids, ammonium ion, biogenic amines, reduced sugars, organic acids, and color parameters of the juice were studied. All three bacteria consumed sugars and amino acids but exhibited different growth patterns. Lactic acid was detected only in L. acidophilus inoculated juice. The content of the phenolic compounds, especially anthocyanins, decreased in juice after inoculation. The CIELa*b* analysis indicated that the juice inoculated with L. acidophilus and O. oeni showed a decrease on a* and b* (less red and yellow) but an increase on L (more lightness), whereas the color attributes of L. brevis inoculated juice did not significantly change. Based on this study, L. brevis showed the most optimal performance in the juice due to its better adaptability and fewer effects on the appearance of juice. This study provided a useful reference on the metabolism of lactic acid bacteria in low pH juice and the evolution of primary and secondary nutrients in juice after inoculated with lactic acid bacteria.

Expanded Graphite/Epoxy/Aliphatic Amine Composites for Bipolar Plates Applications in Polymer Electrolyte Fuel Cells

Suitable conductive fillers for resins and processing conditions are critical factors for the final properties of composite bipolar plates. This research is focused on the development of expanded graphite/epoxy/aliphatic amine composite as a potential replacement for conventional bipolar plates to meet global standards of Polymer Electrolyte Fuel Cells (PEFCs). The synergistic effects on the electrical conductivity of secondary fillers Carbon Black (CB) and Graphite nanoplatelets (GNP) with Expanded Graphite (EG) were studied in a diglycidyl ether of bisphenol A (DGEBA) epoxy/polyether triamine system. Compositions of secondary filler were varied in proportions of 5, 10, 15 and 20 wt % in a fixed 40 wt % EG / Epoxy resin (w/w) to find the right secondary fillers under direct mixing without solvent. A 10 wt % CB displayed the highest electrical conductivity around 3.05 QUOTE x10-2 S/cm. For a 60 wt % EG/10 wt % CB composite, the electrical conductivity (in plane) and flexural strength were at about 19 S/cm and 22 MPa, respectively.

Experimental analysis of waste polyurethane from household appliances and its utilization possibilities

Polyurethane has a good insulation characteristic, and it is widely used as an insulation and lining material for refrigerators. Nevertheless, at the end of a product's lifetime, serious problems arise related to waste management. Recently, energy recovery has been marked as a promising solution, especially, waste-to-energy applications. To find an appropriate application for such waste, a thermal analysis was performed. An experimental analysis of polyurethane (PU) waste material was performed by the method of pyrolysis gas chromatography with mass spectrometric detection (Py-GC/MS) at various pyrolytic temperatures, namely, at 500, 600 and 700 °C. Waste polyurethane foam was conducted to investigations in the form of a bulk sample and sorted grain-size samples with a goal to detect the chemical composition of the pyrolysate. The investigation revealed various groups of organic compounds such as heterocyclic compounds of nitrogen and simple and polycyclic aromatic hydrocarbons, while notable concentrations of compounds containing chlorine were detected as well. The experimental analysis found differences in the composition of amines and other compounds and in the dependence on grain size composition. Bulk samples produced the highest concentration of amines (˃ 40%) at a temperature of 500 °C. The sample homogenization led to a significant increase in amines production. Polyurethane waste of grain size from 0.125 to 0.25 mm contained approximately 80% amines. The pyrolysis of the bulk sample at 600 °C yielded only 24% nitrogen heterocyclic compounds, while from the sorted grain-size <0.045 mm and 0.045–0.063 mm, yields were increased to 47.4 and 45.7%, respectively.

Plasma Electrochemical Synthesis of Few-Layer Graphene Structures for Modification of Epoxy Binder

Few-layer graphene structures synthesized by the plasma electrochemical method are used as modifiers of epoxy binders. It is shown that the obtained structures have the maximum positive effect on the strength characteristics of a cured epoxy–amine composition at a concentration of 0.2 wt %.

Performance Enhancement of Polymeric Blend Membranes Incorporation of Methyl Diethanol amine for CO2/CH4 Separation

For efficient gas separation the membrane technology is rapidly growing day by day and it is more economical and effectual than past technologies. The main objective of this study is to synthesis polymer blend membranes (PBM) using glassy polysulfone (PSU) and rubbery polyvinyl acetate (PVAc) with the addition of methyl diethanol amine for removal of CO2 from CH4. The PBM were developed by varying the composition of PVAc ranging from 5 to 20 wt% with 80 to 100 wt% PSU in DMAc solvent. The amine composition was added to the blend and kept at 10 wt%. The present of MDEA in the PBM had increased the CO2 permeance as compare with the based polymer membranes. However as the operating pressure increased from 2 to 10 bar, the PBM (PSU95%/PVAc5%) with MDEA was found to increase significantly the permeance of CO2, hence increasing the separation factor from 9.980.02 to 30.190.49. EPBM was found a very promising to be used for CO2/CH4 separation.

Ultrafast Epoxy–Amine Photopolyaddition

A new generation of light-induced production of polymeric materials is presented here. In detail, we propose to use photoacidic catalysis during the well-known epoxy–amine polyaddition reaction: it is now referred to as “epoxy–amine photopolyaddition”. Soft irradiation (405 nm visible light, 150–450 mW/cm2) of a photosensitizer/iodonium salt system leads to the production of superacids (e.g., H+, PF6–) that spectacularly enhance state-of-the-art epoxy–amine polyaddition kinetics: <3 min is necessary to obtain full conversion when >3 h is required to complete the reaction without light. Also, photoactivation greatly enhances final epoxy and amine conversions which resulted in increases (+15 °C) of the glass transition temperature of the final 3D polymer networks. This work clearly shows the extremely versatile applications for epoxy–amine photopolyaddition: thin layers (40 μm), thick layers (up to 2.5 cm), and composites (45 wt % fillers). This work paves the path toward ultrafast production of epoxy–amine composites and adhesives.

Designing CO 2 Absorption Columns with Activated Amine Solutions

CO2 absorption into chemical solvents has been a growing industrial market for decades. Currently, activated methyldiethanolamines (aMDEAs) in aqueous solutions are quite often used as solvents. There are several amine compositions available on the market, and most often these solvents are activated. For designing a CO2 absorption tower with activated amine, the chemical reaction in the liquid phase must be considered properly. At the column top, the fully reactive amine enters the column, whereby at the column bottom, the solvent is almost inactive. The highly exothermic CO2 reaction with the activated amine generates heat in the solvent, leading to temperature peaks along the tower. This paper will discuss especially structured and random packings used in industrial CO2 chemisorption columns. It will disclose information about packing characteristics and parameters to look at for selecting the preferred device. The paper will also discuss prediction models recommended for use with such processes.