Ethanolamine Solution Research Articles

Fabricating electrochemical aptasensors for detecting aflatoxin B1 via layer-by-layer self-assembly

Developing high-performance sensors for detecting mycotoxin is of great significance for food safety. Herein, a novel electrochemical aptasensor for the detection of aflatoxin B1 (AFB1) was fabricated via layer-by-layer self-assembly technology. Positively charged poly (diallyl dimethylammonium chloride) modified graphene nanosheets and negatively charged carboxylated polystyrene nanospheres were alternately deposited on the electrode. The resulting multi-layered sandwich structured electrode afforded abundant electrochemical active sites and excellent conductivity. The aptamer of AFB1 was immobilized to the surface of the carboxyl-functionalized polystyrene nanospheres via an amide bond. The electrode was treated by solutions of ethanolamine and bovine serum albumin to improve the specific selectivity. The charge transfer resistance of the electrodes as determined from the Nyquist plots was well correlated with the concentration of AFB1 in the samples. The optimized electrochemical aptasensor exhibited a limit of detection of 0.002 ng mL−1 and outstanding stability after 30 days, rendering it to be one of the best aptasensors for the detection of mycotoxin reported in the literature. The electrochemical aptasensor was practically employed for the detection of AFB1 in oil and soy sauce, yielding recovery values in the range of 94.5 and 103.3%.

Experimental results of advanced technological modifications for a CO2 capture process using amine scrubbing

This paper provides a discussion of the experimental results obtained at the amine-based carbon capture pilot plant having the capacity of 200 m3n/h of flue gas, using 30 wt% ethanolamine solution as a solvent. The objective was to prove the superiority of application of advanced amine flow systems as well as of the novel stripper internal heater fulfilling pilot Technology Readiness Level. Standard process flow sheet, multi absorber feed and split-flow process modifications with and without stripper interheating were examined. A vast number of process parameters were recorded during the trials. The data were critically analysed, compared and presented in the paper. Demonstrated process flow modifications resulted in a reduction of the reboiler heat duty by about 5%, while using internal stripper interheatingby 9÷11 %, comparing to standard amine-based carbon capture plant.

Improved Ti species distribution and hierarchical pores in TS-1: towards regeneration of TS-1 deactivated due to alkali corrosion

TS-1 deactivated in industrial cyclohexanone ammoximation can be effectively regenerated by hydrothermal treatment with TPABr and ethanolamine solution.

A facile strategy for enhanced performance of inverted organic solar cells based on low-temperature solution-processed SnO2 electron transport layer

High-efficiency organic solar cells (OSCs) based on low-temperature (LT) processed SnO2 electron transport layer (ETL) are promising for their commercial use. However, high density of traps and large contact barrier for carriers at the interface between LT SnO2 and the active layer has been reported. To solve the problem, various interface modifying layer materials, such as PFN, has been introduced. Currently, the fabrication process of such interface modifying layer materials is complex and expensive. Herein, a facile strategy involved a polar solvent ethanolamine (EA) is introduced to modify LT SnO2 surface. By soaking the SnO2 film into EA solution in 2-Methoxyethanol (2-ME), EA can easily anchor into SnO2 film surface and forms a continuous monomolecular layer via dehydration reaction. The whole process is green and highly compatible with a roll-to-roll process. Further study suggests that the deep trap centers on SnO2 surface are substantially reduced and the built-in potential in OSCs is reinforced. Finally, OSCs based on EA-modified SnO2 demonstrated an enhanced power conversion efficiency from 10.71% to 12.45% which was comparable to those based on ZnO (12.26%) under the same experiment parameters. Our work boosts the development of the inverted OSCs with easy fabrication and compatibility with roll-to-roll process.

Transient N4 -Acyl-DNA Protection against Cleavage by Restriction Endonucleases.

A set of five N4 -acyl-modified 2'-deoxycytidine 5'-triphosphates were incorporated into modified DNA by using phi29 DNA polymerase, and cleavage by selected restriction endonucleases was studied. Modified DNA containing N4 -acyl functional groups in either one or both strands of a DNA molecule was resistant to the majority of restriction enzymes tested, whereas modifications outside of the recognition sequences were well tolerated. The N4 -acylated cytidine derivatives were subjected to competitive nucleotide incorporation by using phi29 DNA polymerase, showing that a high-fidelity phi29 DNA polymerase efficiently used the modified analogues in the presence of its natural counterpart. These N4 modifications were also demonstrated to be easily removed in an aqueous ethanolamine solution, in which all steps, including primer extension, demodification, and cleavage by restriction endonuclease, could be performed in a one-pot procedure that eliminated additional purification stages. It is suggested that N4 -modified nucleotides are promising building blocks for a programmable; transient; and, most importantly, straightforward DNA protection against specific endonucleases.

Absorption of Carbon Dioxide Using Ethanolamine-Based Deep Eutectic Solvents

The development of a new, green CO2 absorbent with high energy utilization and low solvent loss can replace CO2 capture by ethanolamine solution, which is currently a necessary and important issue....

Modeling Equilibrium Systems of Amine‐Based CO2 Capture by Implementing Machine Learning Approaches

Precise calculation of carbon dioxide equilibrium solubility in aqueous amine solutions is decisive in the success of establishment or maintenance of amine‐based absorptive carbon dioxide capture processes. To implement the AdaBoost algorithm in conjunction with the classification and regression tree (AdaBoost‐CART) aimed at developing models to accurately estimate the equilibrium absorption of carbon dioxide in ethanolamine solutions, experimental data for monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA) systems were gathered from the literature. Furthermore, neural‐based models were developed using the collected databank as the basis of comparison. The results of the presented models were compared to the results of the available models in the literature. It was found that the proposed AdaBoost‐CART models for the investigated amine systems present more precise and reliable outputs compared to the results of the neural‐based and literature models. In a respective order, the introduced AdaBoost‐CART models for MEA, DEA, and TEA solutions show average absolute relative deviation percent of 0.51, 2.76, and 1.41 which indicate their reliability and superiority over other models. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019

Purification of Biohydrogen Produced From Palm Oil Mill Effluent Fermentation for Fuel Cell Application

Fermentation of palm oil mill effluent (POME) produces biohydrogen in a mixture at a specific set condition. This research was conducted to purify the produced mixed biohydrogen via absorption and membrane techniques. Three different solvents, methyl ethanolamine (MEA), ammonia (NH3) and potassium hydroxide (KOH) solutions, were used in absorption technique. The highest H2 purity was found using 1M MEA solution with 5.0 ml/s feed mixed gas flow rate at 60 minutes absorption time. Meanwhile, the purified biohydrogen using a polysulfone membrane had the highest H2 purity at 2~3 bar operating pressure. Upon testing with proton exchange membrane fuel cell (PEMFC), the highest current and power produced at 100% H2 were 1.66 A and 8.1 W, while the lowest were produced at 50/50 vol% H2/CO2 (0.32 A and 0.49 W). These results proved that both purification techniques have significant potential for H2 purification efficiency.

Density, Viscosity, and N2O Solubility of Aqueous Solutions of MEA, BmimBF4, and Their Mixtures from 293.15 to 333.15 K

Densities and viscosities of aqueous solutions of ethanolamine (MEA), 1-butyl-3-methylimidazolium tetrafluoroborate (BmimBF4), and their mixtures were measured. The experiments covered the following mole fraction ranges: 1.00–9.38 mol % of BmimBF4 in its aqueous solutions, 3.94–21.97 mol % of MEA in its aqueous solutions, and 1.32–17.01 mol % of MEA + 5.10–34.02 mol % of BmimBF4 in the mixtures. The results are compared with available data in the literature and correlated using a semiempirical formula as functions of the temperature and concentration of MEA and BmimBF4. At the concentration suitable for the CO2 capture, the viscosity of the hybrid absorbent did not significantly increase by the addition of BmimBF4. Moreover, the addition of BmimBF4 reduced the Henry’s law constant, which is significant for reaction kinetics.

Facile, Quick, and Gram‐Scale Synthesis of Ultralong‐Lifetime Room‐Temperature‐Phosphorescent Carbon Dots by Microwave Irradiation

AbstractLong‐lifetime room‐temperature phosphorescence (RTP) materials are important for many applications, but they are highly challenging materials owing to the spin‐forbidden nature of triplet exciton transitions. Herein, a facile, quick and gram‐scale method for the preparation of ultralong RTP (URTP) carbon dots (CDs) was developed via microwave‐assisted heating of ethanolamine and phosphoric acid aqueous solution. The CDs exhibit the longest RTP lifetime, 1.46 s (more than 10 s to naked eye) for CDs‐based materials to date. The doping of N and P elements is critical for the URTP which is considered to be favored by a n→π* transition facilitating intersystem crossing (ISC) for effectively populating triplet excitons. In addition, possibilities of formation of hydrogen bonds in the interior of the CDs may also play a significant role in producing RTP. Potential applications of the URTP CDs in the fields of anti‐counterfeiting and information protection are proposed and demonstrated.

Facile, Quick, and Gram‐Scale Synthesis of Ultralong‐Lifetime Room‐Temperature‐Phosphorescent Carbon Dots by Microwave Irradiation

Long-lifetime room-temperature phosphorescence (RTP) materials are important for many applications, but they are highly challenging materials owing to the spin-forbidden nature of triplet exciton transitions. Herein, a facile, quick and gram-scale method for the preparation of ultralong RTP (URTP) carbon dots (CDs) was developed via microwave-assisted heating of ethanolamine and phosphoric acid aqueous solution. The CDs exhibit the longest RTP lifetime, 1.46 s (more than 10 s to naked eye) for CDs-based materials to date. The doping of N and P elements is critical for the URTP which is considered to be favored by a n→π* transition facilitating intersystem crossing (ISC) for effectively populating triplet excitons. In addition, possibilities of formation of hydrogen bonds in the interior of the CDs may also play a significant role in producing RTP. Potential applications of the URTP CDs in the fields of anti-counterfeiting and information protection are proposed and demonstrated.

Extended Investigation of Electrochemical CO2 Reduction in Ethanolamine Solutions by SECM

AbstractThe electrochemical reduction of carbon dioxide is very much in the focus of interest today. Intensive research is carried out in leading laboratories trying to work out methods for making useful materials from this unwanted greenhouse gas using solar or wind power generated excess electric energy. In this work, electrochemical reduction experiments are carried out in homemade cells supplied with different metal electrodes. Electrolytes containing carbon dioxide absorbing components like monoethanolamine (MEA) or KHCO3, KOH, and K2CO3 solutions are used. Metal‐containing species were noticed in the used electrolytes after being in contact with the metal working electrodes. Therefore parallel to the electrochemical measurements, the metal components in the electrolyte were checked with atomic absorption methods for getting better insight into the nature of the electrode passivation. This paper attempts to compare the behavior of different electrode materials (copper, nickel) in CO2 capturing media, and investigate of the products of the electrolysis using Scanning Electrochemical Microscopy (SECM), Atomic Absorption Spectroscopy (AAS) and gas chromatography.

The enhancement performances of cotton stalk fiber/PVC composites by sequential two steps modification

ABSTRACTIn the present study, the cotton stalk fiber (CSF) was modified by sequential two steps of alkali and copper ethanolamine (CE) solution treatment. The unmodified and modified CSF/poly(vinyl chloride) (CSF/PVC) composites were prepared. The mechanical and physical performances of the various CSF/PVC composites were studied comparatively. By the modification of CE solution, all the tensile strength, tensile modulus, impact strength, water resistance, and heat distortion temperature of samples were enhanced continuously. The sample with comprehensive properties was obtained using 2% concentration of CE. The composites were also prepared with different CSF content. By increasing the CSF loading, all the tensile strength, elongation at breakage, tensile modulus, and heat distortion temperature of samples were enhanced. The existence of copper on the surface of CSF improved the thermal stability of the CSF/PVC composites. Water retention value, oil retention value, and scanning electron microscope were applied to reveal the components and microscopic change of the composites. The possible reaction mechanism of modification was proposed based on the experimental results and according to the previous literature. This method reported here may provide a new way for the fabrication of CSF/PVC composite in engineering applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46090.

The Study of Carbon Dioxide Removal in Membrane Module by Single and Mixture of Alkanolamine Aqueous Solutions

This work presents an investigation on the performance of CO2absorption into aqueous alkanolamine solution using a hollow fiber membrane gas–liquid contactor. Aqueous solution of ethanolamine (MEA), diethanolamine (DEA), 2–amino–2–methyl–1–propanol (AMP) and piperazine anhydrous (PZ) were chosen as the absorption liquids. A microporous hollow fiber membrane made of polyvinylidene fluoride (PVDF) was used as the medium for gasliquid absorption process. In this study, the operating temperature is fixed at 30°C, while the flowrate of CO2 and alkanolamine were in the range of 1000–5000 ml/min and 50–280 ml/min respectively. The feed gas was introduced directly to the shell of the module at 1–1.5 bar and the liquid flowed through the fiber lumen side. The CO2 transfer through the membrane was found to be reaction controlled and dependent on the type of amine used. The use of piperazine as an accelerator in the mixture of the absorption liquids gives a good impact on increasing the performance for the rate of CO2 transfer.

MEA and Piperazine Corrosion of Carbon Steel and Stainless Steel

Two methods were developed to measure the corrosion of 1010 carbon steel and 316L stainless steel in solutions of ethanolamine, piperazine, and several other linear amines at high temperature and pressure. The effect of amine concentration, CO2 loading, and temperature were measured. The first method uses Swagelok® steel cylinders heated in ovens to accelerate corrosion of the metal surface, which is then estimated by measuring dissolved metal. Although the steel cylinder method gave reasonable corrosion rates for 316L SS, it significantly under predicted the corrosion rate of 1010 CS. This is likely due to the weakly adhering passive film that was protective only at the stagnant conditions in the non-agitated cylinders. The second method uses an electrical resistance probe to measure corrosion in a bench-scale thermosiphon apparatus, which was constructed to simulate more realistic flow conditions. Both methods were used to examine a series of linear amines and their results were compared. Corrosion of the electrical resistance probe by a variety of degraded piperazine solutions from pilot plants was measured. Loading was found to be the dominant factor in piperazine corrosion. Counterintuitively, corrosion rates of stainless steel decrease at high loadings, probably due to the formation of a FeCO3 film. Degraded piperazine was only slightly more corrosive than clean piperazine at most conditions. Over a wide variety of conditions, 1010 carbon steel showed lower corrosion rates in piperazine solutions than 316L stainless steel.

Mass transfer performance and correlations for CO2 absorption into aqueous blended of DEEA/MEA in a random packed column

The mass transfer performance of CO2 absorption into blended N,N‐diethylethanolamine (DEEA)/ethanolamine (MEA) solutions was investigated using a lab‐scale absorber (H = 1.28 m, D = 28 mm) packed with Dixon ring random packing. The mass transfer coefficient KGav, the unit volume absorption rate Φ, outlet concentration of CO2 (yCO2), and the bottom temperature Tbot of CO2 in aqueous DEEA/MEA solutions were determined over the feed temperature range of 298.15–323.15 K, lean CO2 loading of 0.15–0.31 mol/mol, over a wide range of liquid flow rate of 3.90–9.75 m3/m2‐h, by using inert gas flow rate of 26.11–39.17 kmol/m2‐h and 6–18 kPa CO2 partial pressure. The results show that liquid feed temperature, lean CO2 loading, liquid flow rate, and CO2 partial pressure had significant effect on those parameters. However, the inert gas flow rate had little effect. To allow the mass transfer data to be really utilized, KGav and yout correlations for the prediction of mass transfer performance were proposed and discussed. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3048–3057, 2017

Tuning the optical band gap and stoichiometric ratio of chemically synthesized lead selenide thin films by controlling film thickness

Lead selenide (PbSe) thin films with different thickness were deposited by chemical bath deposition method at a bath temperature of 75 °C. The films were synthesized from an aqueous solution of lead acetate trihydrate, ethanolamine, sodium hydroxide and sodium selenosulphate. Structural, chemical composition, optical, and surface morphology of the PbSe thin films were investigated by varieties of techniques to study the influence of film thickness on the material properties. All the as-deposited thin films shows a face centered cubic crystal structure with a preferred orientation along the (200) plan. The XRD results also demonstrated that film thickness had a strong influence on the average crystalline size, texture of coefficients and dislocation density of PbSe thin films. The EDAX study verified that the stoichiometric ratio of the prepared PbSe thin films enhanced as the film thickness increased. The surface roughness of PbSe thin films were examined by atomic force microscopy and it was noticed that root mean square and average roughness increased with film thickness. The optical absorption spectroscopy study revealed that the optical band gap of the PbSe thin films tuned over a wide spectral range by simple and cost effective route from 1.07 eV to 1.50 eV. The photoluminescence study verified that increasing the film thickness enhances the emission intensity and broadens of the emission rang.

Chemisorption of sulfur dioxide by aqueous solutions of ethanolamines under static conditions

Chemisorption of sulfur dioxide by water and aqueous solutions of ethanolamines has been studied under static conditions. The solubility of SO2 in these media depends on its partial pressure and рН as well as basicity and hydration properties of ethanolamines. The contributions of the chemical and physical components in the total solubility have been determined. Decrease in the basicity of ethanolamine and increase in the degree of its hydration in the methylmono-, mono-, di-, and triethanolamines series results in the decrease in the salting-in constant of the Sechenov equation for physical absorption of SO2.

Electrochemical Properties of Ni-TiO2/NiO Nanocomposite in Amine-Containing Solutions at the Elevated Temperature

For the development of non-precious-metal-based materials for the assorted electrochemical engineering fields as an alternative for precious metals, we report promising potential of Ni-TiO2/NiO nanocomposite which is synthesized by self-catalytic reactions on metallic substrates. Microstructure characterization via TEM shows the well-dispersed TiO2 nanoparticles in Ni alloy matrix. Electrochemical properties are investigated via linear sweep voltammetry (LSV) in 125, 150, and 175 oC of 15 ppm ethanolamine (ETA) solution (pH25 9.3). LSV were carried out in order to reveal anodic polarization behaviors (Figure 1) to investigate a hydrogen evolution reaction (HER) on catalytic surface. The results give while Ni/NiO represents electrocatalytic activity until 125 oC, Ni-TiO2/NiO does until 150 oC. This tendency can be explained by the dissolution of NiO species into Ni2+ ions and TiO2 nanoparticles suppress the corrosion of the Ni frame. Therefore, it can be concluded that the embedded noble and solid nanoparticle can enhance electrocatalytic activity even at the elevated temperatures. Figure 1

A Study on Capillary-porous Structure of Wood Modified with Boron-Nitrogen Compounds

Capillary-porous structure of wood modified with boron-nitrogen compounds was studies by sorption methods. Specific surface area of the suport was found to be reduced up to three folds.Changes of structure of the wood surface layer treated with aqueas solutions of boric acid and ethanolamines as well as the possibility of forming 4-coordinate boron-nitrogen compounds in situ, directly on the wood surface, were investigated. Stepwise treatment of wood surface with boric acid and ethanolamines in different order was found not to cause significant changes in the capillary-porous structure, which is apparently due to the difficulties of formation of 4-coordinate boron-nitrogen compounds in situ.