Dehydration Process Research Articles

Durability of Two-Component Grout in Tunneling Applications: A Laboratory Test Campaign

Today, two-component grout is the most widely used backfilling technology in shielded mechanized tunneling. Despite its intensive use, however, very scant information pertaining to the durability of this material is available in the scientific literature. In this work, the aging of two-component grout is studied by curing grout samples using three different modalities. Furthermore, the action of air on two-component grout is studied by assessing the dehydration process, which is a phenomenon that occurs when the material is cured without being completely embedded in soil/rock. Uniaxial compression tests and three-point flexural tests have been carried out for mechanical characterization. The results reveal that in a curing environment made of sand, a moisture of 5% is sufficient to guarantee correct curing of the grout and extend the mechanical performance to three years, whereas the action of air is potentially dangerous, since the grout suffers strongly from dehydration. Despite this dehydration process, however, the mechanical performance of the grout also tends to increase for samples cured under the action of air until a very high level of cracking and shrinkage is reached. A discussion of the limitations on the uniaxial compression strength as the main mechanical parameter for the characterization of two-component grout concludes the work.

Capturing drought stress signals: The potential of dendrometers for monitoring tree water status

Abstract The severity of droughts is expected to increase with climate change, leading to more frequent tree mortality and a decline in forest ecosystem services. Consequently, there is an urgent need for monitoring networks to provide early warnings of drought impacts on forests. Dendrometers capturing stem diameter variations may offer a simple and relatively low-cost opportunity. However, the links between stem shrinkage, a direct expression of tree water deficit (TWD), and hydraulic stress are not well understood thus far. In this study, we exposed two widespread conifers Pinus sylvestris and Larix decidua to lethal dehydration by withholding water and closely monitored TWD, midday water potential ($\psi $), and midday stomatal conductance ($g_{s}$) under controlled greenhouse conditions. We found strong relationships between the three variables throughout the dehydration process, particularly suggesting the potential for continuous $\psi $ predictions and stomatal closure assessments. However, the relationships decoupled during recovery from severe drought. We also identified TWD thresholds that signal the onset of drought stress and tissue damage, providing insights into stress impacts and recovery potential. While these findings are promising, challenges remain in practically transferring them to field set-ups by suitable TWD normalization. Importantly, we observed that midday $g_{s}$ was drastically reduced when TWD persisted overnight, providing a directly applicable drought stress signal that does not require normalization. In conclusion, while challenges remain, our results highlight the potential of dendrometers for monitoring tree water dynamics. Implementing dendrometer networks could support the development of early-warning metrics for drought impacts, enabling large-scale monitoring in diverse settings, such as urban areas and forest ecosystems.

Smoked Fish Salam: Development and Sensory Analysis

Objective: The aim of this study is to develop smoked salamis (cold and hot) from mechanically separated meat (MSM) of tilapia, and to evaluate their acceptance through sensory analysis. Theoretical Framework: With the increase in fish production, large quantities of fish by-products are also generated, such as carcasses, heads, fillets, among others with high nutritional value that can be used in human and animal nutrition. Method: The methodology adopted for this research includes a control formulation subjected to smoking (cold and hot), and two others with the inclusion of 10 and 20% of CMS in natura, totaling four treatments. In the dehydration process, the salamis were weighed and subjected to pre-drying in a forced ventilation oven for three hours at 55ºC. Then, they were placed in a stainless steel smoker that produced smoke by burning sawdust (4h/55ºC). The cold smoking process was carried out using 20% of liquid smoke/volume of water, where the salamis were immersed for 15 minutes, drained and taken to the oven (4h/55ºC). At the end of the process, the weight loss of the sausages was calculated and sensory analyses were performed, where 50 untrained judges evaluated the products in terms of acceptance and purchase intention. Results and Discussion: The results obtained revealed that total losses ranged from 16.71 to 32.79%. The type of smoking influenced the acceptance of the salamis (p<0.05), where color and aroma were the parameters that presented the highest values for hot-smoked salamis, as observed for purchase intention. Research Implications: Fish salamis enriched with fish protein sources are an excellent alternative for human nutrition, as they represent an excellent nutritional source for people who are concerned about healthy foods. There are several studies using animal protein sources such as fish to prepare healthy and easy-to-prepare foods, since due to people's fast-paced routines today, they need quick and healthy foods. Originality/value: this study contributes to the literature by highlighting the supplementation of food with processed fish by-products and enhanced in the form of fish sausages.

Numerical modeling the process of deep slab dehydration and magmatism

This study uses a 2D high-resolution thermo-mechanical coupled model to investigate the dynamic processes of deep plate hydration, dehydration, and subsequent magmatic activity in ocean-continent subduction zones. We reveal the pathways and temporal evolution of water transport to the deep mantle during the subduction process. Plate dehydration plays a critical role in triggering partial melting of the deep mantle and related magmatic activity. Our study shows significant differences in the volumes of melt produced at different depths, with dehydration reactions in deeper regions being weaker compared to shallower ones. It takes a longer time to reach the suitable P-T conditions for hydrous melting in the deep mantle. The results highlight the geophysical significance of water transport in deep subduction zones and its role in magmatic processes, particularly in the formation of magma chambers beneath continental plates.

Interfacial and mass transport phenomena in the tri-ethylene glycol-methane system at process conditions of natural gas dehydration

AbstractUnderstanding the phase and interphase behavior at equilibrium and during the mass transfer between two adjacent fluid phases is relevant for optimizing and designing efficient separation processes. This study experimentally investigates the interfacial and transport behavior of systems comprising tri-ethylene glycol (TEG) and methane (CH4) under conditions relevant to the gas dehydration process. A comprehensive review of the interfacial tension (IFT) and diffusivity of systems involving non-polar and polar compounds at elevated pressures was studied. However, a research gap exists, particularly concerning the interfacial tension of systems involving TEG, TEG + water, and different types of gases as well as the diffusivity of CH4 in TEG. To address this gap, this study presents new data on mixture densities, interfacial tension, and drop volumes of TEG and TEG + water in CH4 and CH4 + CO2 mixtures at temperatures ranging from 20 to 50 °C and pressures up to 250 bar using the oscillating U-tube and pendant drop methods, respectively. Additionally, time-dependent fluid mixture densities and TEG droplet volumetric expansion, coupled with an analytical approach for the binary diffusion were applied to determine the CH4 solubility and diffusivity in TEG. The results show that IFT and drop volume of TEG and TEG + water in CH4 and CH4 + CO2 mixtures decrease with increasing pressure. The presence of water increases the IFT of TEG-CH4 up to $$\sim$$ ∼ 5mN/m, while CO2 reduces it by $$\sim$$ ∼ 2mN/m. Interestingly, the IFT and drop volume of TEG-CH4 show no significant change at elevated pressures when temperatures rise from 20 to 50 °C. IFT remains relatively constant over time at moderate pressures but decreases by $$\sim$$ ∼ 3mN/m at an elevated pressure of 150 bar, suggesting methane solubilization into TEG to have a significant influence which is confirmed by TEG drop volume expansion. The diffusivity of CH4 in TEG at 150 bar and 50 °C is determined to be in the range of 10–10 m2/s, which is in agreement with the diffusivity of CH4 in liquids of similar viscosity, i.e. according correlations may be applied as good engineering practice. To the best of our knowledge, there is no such comprehensive work on the properties of fluid mixtures relevant in gas dehydration processes published up to date.

Mixed (NH4)2Mn0.47Cu0.53(SO4)2(H2O)6 Tutton salt: A novel optical material for solar-blind technology

In this paper, a novel mixed Tutton salt (NH4)2Mn0.47Cu0.53(SO4)2(H2O)6 obtained in single crystal form is described. Their structural, thermal, electrical, and spectroscopic properties have been examined, and their possible uses are discussed. The salt crystallizes in a monoclinic symmetry (P21/c) and exhibits thermal stability between 300-333 K. Above this temperature, the crystal undergoes phase changes associated with dehydration and crystallization processes. 231 optical phonons distributed between 50 and 4000 cm–1, calculated through density functional perturbation theory, were used to accurately assign vibrational modes in experimental FT-IR and Raman spectra. Additional computational studies using Hirshfeld surfaces have revealed that H···O/O···H and H···H intermolecular contacts are crucial interactions for stabilizing the crystal lattice. Electrical characteristics (resistivity = 1160 MΩ·cm; capacitance = 3.6 pF) and optical data (bandgap = 4.27 eV) depict a typical behavior of nonpolar dielectric materials. UV-Vis-NIR transmittance spectrum has shown deep light blocking in the UV-C and Vis/NIR spectral regions and high transmittance levels (reaching 98.5%) in the UV-B/-A/Vis range. The photoresponse findings point out that (NH4)2Mn0.47Cu0.53(SO4)2(H2O)6 is a promising light-absorbing material for solar-blind photodetection devices operating in the 200-280 nm interval. The crystal as a bandpass filter (280-615 nm) or a cut-off filter (615-1000 nm) are also excellent prospects for application.

Cryo-X-Ray Phase Contrast Imaging Enables Combined 3D Structural Quantification and Nucleic Acid Analysis of Myocardial Biopsies.

Snap-frozen biopsies serve as a valuable clinical resource of archival material for disease research, as they enable a comprehensive array of downstream analyses to be performed, including extraction and sequencing of nucleic acids. Obtaining three-dimensional (3D) structural information before multi-omics is more challenging but can potentially allow for better characterization of tissues and targeting of clinically relevant cells. Conventional histological techniques are limited in this regard due to their destructive nature and the reconstruction artifacts produced by sectioning, dehydration, and chemical processing. These limitations are particularly notable in soft tissues such as the heart. In this study, the feasibility of using synchrotron-based cryo-X-ray phase contrast imaging (cryo-X-PCI) of snap-frozen myocardial biopsies is assessed and 3D structure tensor analysis of aggregated myocytes, followed by nucleic acid (DNA and RNA) extraction and analysis. It is shown that optimal sample preparation is the key driver for successful structural and nucleic acid preservation which is unaffected by the process of cryo-X-PCI. It is proposed that cryo-X-PCI has clinical value for 3D tissue analysis of cardiac and potentially non-cardiac soft tissue biopsies before nucleic acid investigation.

Simulation study on additive-promoted microwave dehydration of lignite

ABSTRACT Microwave dehydration technology has been widely used in coal processing methods due to its unique advantages. Adding additives with high dielectric loss to coal can enhance the microwave absorption capacity of coal, so as to effectively improve the dehydration process. In order to understand the change and distribution of multi-fields in the microwave drying process of lignite under the action of different additives, verify the experiment and reduce the cost and number of experiments, this paper established a multi-field coupling model of electromagnetic field and heat and mass transfer of multiphase porous media based on COMSOL Multiphysics, so as to simulate the microwave drying process of lignite. The results show that the distribution areas of electromagnetic field, temperature field, and vapor in coal are basically the same, while the distribution of liquid water is just the opposite. With the enhancement of additive promotion effect, the parts with strong electromagnetic field strength increase, the hot spots of temperature field increase, the maximum temperature, and minimum temperature increase, and the water content in coal samples decreases. The promotion effect of additives on the microwave dehydration process of lignite is consistent with the experiment.

Effectiveness Evaluation of Silicone Oil Emulsion In Situ Polymerization for Dehydration of Waterlogged Wooden Artifacts

Organosilicon materials have shown potential as dehydration agents for waterlogged wooden artifacts. These materials can polymerize under normal conditions to form polymers with favorable mechanical strength, antibacterial properties, and aging resistance. However, the insolubility of most organosilicon hindered their penetration into waterlogged wood, which may lead to an unwanted cracking. This study aimed to evaluate the effectiveness of polydimethylsiloxane (PDMS) and hydroxy-terminated polydimethylsiloxane (PDMS-OH) with low viscosity and moderate reactivity for dehydrating waterlogged wooden artifacts from the Nanhai No.1 shipwreck. Four surfactants ((3–aminopropyl) triethoxysilane (APTES), alkyl polyoxyethylene ether (APEO), tri-methylstearylammonium chloride (STAC), and fatty alcohol polyoxyethylene ether (AEO)) and cosurfactant were employed to transform the two kinds of water-repellent silicone oils into eight groups of highly permeable oil-in-water (O/W) emulsions. Under the catalysis of a neutral catalyst, in situ polymerization occurred within the wood cells. Group P2-2 formulated with PDMS-OH and APEO showed the best efficiency in maintaining the dimensions of the wood during dehydration. The dehydrated wood exhibited a natural color and texture with a minimal volume shrinkage rate of 1.89%. The resulting polymer adhered uniformly to the cell walls, effectively reinforcing the wood cell structure. The weight percent gain of the wood was only 218%, and the pores of the cell lumen were well maintained for future retreatment. This method effectively controlled the sol–gel reaction process of the organosilicon and prevented damage to the wooden artifact during the dehydration process. Moreover, the dehydrated wood samples only experienced a low weight gain of 17% at 95% relative humidity (RH), indicating their great environmental stability.

Study on Mass Transfer and Physicochemical Properties of Avocado During Osmotic Dehydration

A previous study found that mass transfer occurring during the osmotic dehydration (OD) process. This phenomena is possible causing modification in physicochemical properties; therefore, understanding the OD effect on quality attributes is important. This research aimed to study the impact of sucrose concentration and immersion time on the kinetics of mass transfer and the physicochemical properties of avocado (Persea americana var. Miki) during the OD process. The samples were immersed in a sucrose solution (45, 55 and 65 ° Brix) for up to 300 min, then the mass transfer parameter and physicochemical properties were evaluated. The results showed that the highest rate of water removal (WR) was –0.037 g.g–1.h–1 using the 55 ° Brix solution, which also led to an increase in the soluble solid gain (SSG) value to 0.0126 g.g–1.h–1, while the highest WR/SSG ratio was obtained after 180 min of immersion using 65 ° Brix (2.451). A 2nd-order polynomial model accurately describes avocado mass transfer kinetics and their relationship to physicochemical properties. The model showed the best adjustment for WR, SSG, and weight loss (WL), as pointed out by R2 = 0.9671, 0.8968 and 0.9573, respectively. WR has a negative effect on firmness (R2 = 0.9278), vitamin C (R2 = 0.9349), and total fat (R2 = 0.8954). The uptake of sucrose correlated with decrease of vitamin C (R2 = 0.9391), whereas WL also affected the loss of total fat (R2 = 0.8288). The OD process modified the chroma of the avocado by reducing lightness, increasing greenness and yellowness, and yet protecting the flesh from the browning effect. Overall, this study provides insights into the relationship between mass transfer and physicochemical properties, and it is useful to predict the final condition of the osmo-avocado before subsequent processes. HIGHLIGHTS Immersing the avocado in a 55 ° Brix solution resulted in the highest rate of water removal (WR) and soluble solid gain (SSG). The highest ratio of WR and soluble solid gain (WR/SSG) was obtained at 180 min of immersion using a 65 ° Brix solution. The 2nd-order polynomial model fits the mass transfer parameters (WR, SSG, and weight loss/WL). WR contributed to a softened texture, color contrast, degradation of vitamin C, and total fat content. The combination of mass transfer and physicochemical property models is useful for designing the OD process and predicting the final condition of osmo-avocado. GRAPHICAL ABSTRACT

Zwitterionic covalent organic framework membranes for efficient liquid molecular separations

Covalent organic frameworks (COFs) featuring uniform topological structure and devisable functionality have emerged as promising membrane materials. The design and precise manipulation of COF membranes with advanced spatial structure to achieve efficient liquid molecular separations are of great necessity. Herein, zwitterionic COF membranes have been in-situ fabricated on porous polymeric substrates using an interfacial polymerization modification strategy. The continuous defect-free COF membranes with two-dimensional in-plane dominant growth can be achieved by optimizing the fabrication parameters including reaction time, monomer concentration, and catalyst concentration. Subsequent zwitterionic modification thereon not only favors the formation of hydrophilic surface but also improves the sieving capability by sheltering effect. Attributed to the synergistic contribution, the optimized zwitterionic COF membrane possesses a superior separation factor of 2839 with the water content in the permeate up to 99.7 wt%, while maintaining a comparable permeation flux of 3309 g m−2 h−1 during the ethanol dehydration process, outperforming most of other representative membranes. Furthermore, the excellent durability of the zwitterionic COF membrane in the ethanol dehydration process and its efficient separation performance towards other alcohol dehydration systems demonstrate its potential practical applications. The easy scalability of the fabrication and regulation method offers crucial guidance for the engineering of advanced COF membranes in efficient liquid molecular separations.

High Quantum Yields and Energy Transfer Efficiency of Lanthanide‐Based Coordination Polymers as Luminescent Thermometer in Low Temperature Range

ABSTRACTLuminescent lanthanide‐based coordination polymers (LnCPs) present great potential in low‐temperature detection due to their convenience in contactless readout. High quantum yields and energy transfer efficiency are favored by LnCPs as luminescent thermometer. In this work, based on the thermogravimetric analysis and temperature‐dependent powder x‐ray diffraction, coordinated and isolated molecules of [Ln2(mip)3(H2O)8·4H2O]∞ (abbreviated as Ln2MIP) were removed by dehydration process. Combining luminescent measurement and calculation, both quantum yields and energy transfer efficiency between Tb3+ and Eu3+ have been greatly enhanced. Additionally, the Eu3+ intensity of dehydrated Gd0.2Tb1.08Eu0.72MIP displays excellent temperature sensing ability from 77 to 300 K with enhanced relative sensitivity. These results demonstrate the potential of LnCPs in low‐temperature sensing with high quantum yields and energy transfer efficiency.

Enhancing the Nutritional Value and Preservation Quality of Strawberries through an Optimized Osmotic Dehydration Process

Enhancing the Nutritional Value and Preservation Quality of Strawberries through an Optimized Osmotic Dehydration Process

Physiological and gene expression response mechanisms of dehydration process in Cinnamomum cassia (L.) J. Presl seeds.

A critical factor in the storability of recalcitrant seeds is their moisture content (MC), but its effect on the viability of Cinnamomum cassia (L.) J. Presl (C. cassia) seeds is not fully understood. Measured the germination rate, starch and soluble sugar content, and transcriptome of 8 seed samples with different MC obtained by low-temperature drying method. It was found that the germination rate was significantly negatively correlated with MC. The lethal MC was around 15.6%. During the dehydration process, there was a significant increase in the content of soluble sugars and starch. Transcriptome analysis was performed on CK, W3, W6 showed a total of 62.78 Gb of clean data. Among the 30,228 Unigenes, 28,195 were successfully annotated. In the three comparative groups (CK and W3, CK and W6, W3 and W6), 6,842, 7,640, and 11,628 differentially expressed genes (DEGs) were obtained, respectively. These DEGs were found to be involved in a variety of metabolic pathways, including carbon metabolism, amino acid biosynthesis, starch and sucrose metabolism, glycolysis/gluconeogenesis, and nucleotide and amino sugar metabolism. A total of 1,416 common genes were identified among all three comparison groups. Furthermore, among all the DEGs, a total of 71 transcription factor families were identified, with the C2H2 transcription factor family having the highest number of genes. This ground-breaking study sheds light on the physiological response and gene expression profiles of C. cassia seeds after undergoing dehydration treatment, which will provide valuable insights for further research and understanding of this process.

CFD modeling of DME synthesis based on methanol dehydration process by an adiabatic reactor: Characterization

Today, Dimethyl ether (DME) can be used as a fuel in various applications, including as a substitute for diesel fuel. Despite its advantages, there are some challenges associated with DME as a fuel. One of the main challenges is the limited availability of DME refueling stations and the need for dedicated storage facilities due to their different properties compared to traditional fuels. DME shows promise as a clean-burning alternative fuel with the potential to reduce emissions and dependence on fossil fuels, especially in the transportation and power generation sectors. Ongoing research and development efforts are focused on improving production methods, expanding infrastructure, and exploring new applications for DME as a fuel. DME is a colorless gas that can be used as a fuel or as a precursor for the production of other chemicals. The most common method for DME synthesis involves the dehydration of methanol. Methanol is first converted to dimethyl ether by removing a molecule of water. This reaction is typically catalyzed by acidic materials such as alumina or zeolites. In this work, to study the physical properties of the methanol dehydration reaction, CFD modeling of the adiabatic reactor has been accomplished. The researchers showed that the use of an alumina catalyst, which has selective mechanical properties and unique surface properties, is a suitable choice as a catalyst for DME synthesis. The results of this study indicate that laboratory data such as pressure, energy, and velocity in the adiabatic reactor satisfy the reaction conditions well. Also, temperature profile diagrams with changes in temperature, pressure, and velocity show that the reaction of methanol dehydration is strongly dependent on environmental factors and presents different results under the influence of other conditions.

Direct Metal Transfer on Swellable Hydrogel with Dehydration-Induced Physical Adhesion.

Composites of hydrogels and metals are gaining interest because of each material's unique properties. However, the stable adhesion of metals on hydrogels is challenging due to the mechanical mismatch at the soft-hard interface and the liquidity of the water components in hydrogels. We propose a facile physical-adhesion method that involves the dehydration process of hydrogels to transfer metals from a glass substrate. This method is based on the hydrophobic interaction between polymer chains and metals and is stable, even in water. Continuous metal wiring was achieved on a swollen hydrogel, and electrical conduction was effective for a soft electronic device. Therefore, our method could be a versatile method for integrating hydrogels and metals.

Thermodynamic modelling of systems involved in natural gas dehydration with triethylene glycol using a group contribution association model

Natural gas (NG) dehydration through absorption into Triethylene Glycol (TEG) is one of the most important applications in the NG industry. The optimal design of the TEG dehydration process requires a deep understanding of the thermodynamic behavior of mixtures containing TEG, water, hydrocarbons, and other compounds present in natural gas. In this work, the recently developed Universal Mixing Rule – Cubic Plus Association (UMR-CPA) group contribution equation of state (EoS) is extended to these systems. UMR-CPA combines the PR-CPA EoS with the UNIFAC group contribution activity coefficient model through the Universal Mixing Rules. Parameters for pure water, TEG and NG components were determined by accurately fitting vapor pressure, density and heat capacity data. For non-associating compounds, the model leads to overall deviations of 1.2 % in vapor pressures and 6.1 % in isobaric heat capacities. Water properties are also quite accurately described, with overall deviations of approximately 0.4 %, 1.2 % and 5.7 % in vapor pressures, liquid densities and isobaric heat capacities, respectively. The model was then applied to mixtures of water and TEG with gases and hydrocarbons by correlating the proper group interaction parameters. Very satisfactory results were obtained for both vapor-liquid and liquid-liquid phase equilibria in these systems, where also an adequate reproduction of the minimum of hydrocarbon solubility in water was noted. Finally, the UMR-CPA EoS was further validated through the prediction of the phase behavior of ternary systems including TEG and/or water and NG compounds. Very good predictions were achieved for the low TEG and water content in the vapor phase of the TEG-H2O-CH4 ternary system, with absolute deviations of around 0.05 and 23.26 ppm, respectively. Overall, the model yields accurate predictions, suggesting its suitability for designing the TEG dehydration process.

UV‐A Light Dehydration: Kinetics of Microbial Inactivation Against Gram‐Positive and Gram‐Negative Bacteria

ABSTRACTUV‐A light exposure (365 nm, 4.6 ± 0.2 mW/cm2) was combined with low relative humidity (RH) air flow at room temperature to dehydrate sweet potatoes and reduce the population of inoculated bacteria. Control samples underwent dehydration with low RH air at room temperature and in the absence of UV‐A light to assess the importance of UV‐A light in the dehydration and microbial reduction processes. The UV‐A light‐dehydrated sweet potatoes resulted in the removal of approximately 97.2% ± 2% of the original mass of water, which was significantly higher than the control samples. Infrared spectroscopy analyses confirmed the preservation of the physical and chemical integrity of the UV‐A light‐dehydrated samples. Despite the absence of pretreatments for enzyme inactivation, the UV‐A light‐dehydrated sweet potato did not exhibit a decrease in luminosity or darkening of color often associated with dehydration. Additionally, the utilization of UV‐A light for the dehydration of sweet potatoes inoculated with ~6 log(CFU/gDry solids) of Escherichia coli K12 resulted in a 99.9% ± 0.1% or 3.1 ± 0.5 log(CFU/gDry solids) reduction with only a 92.2% ± 0.1% or 1.3 ± 0.5 log(CFU/gDry solids) reduction resulting from the control samples dehydrated without UV‐A exposure. In the case of samples inoculated with ~6 log(CFU/gDry solids) of Listeria innocua L2 there was a 99.2% ± 0.5% or 2.2 ± 0.3 log(CFU/gDry solids) reduction when UV‐A light was utilized and only a 60.9% ± 10.3% or 0.4 ± 0.1 log(CFU/gDry solids) reduction when samples were dehydrated in its absence.

A novel TFNi pervaporation membrane with g-C3N4 quantum dots for high-efficiency IPA dehydration

Pervaporation (PV) shows significant potential for the highly selective isopropanol (IPA). The pursuit of developing PV membranes with outstanding separation effect and enduring high purity permeation is an indispensable goal. Based on polyamide (PA) separation layers, a polydopamine (PDA) mixed g-C3N4 quantum dots (gCNQDs) coating as the interlayer was deposited onto a porous ceramic hollow fiber substrate to fabricate thin-film nanocomposite membranes with an interlayer (TFNi). The nanocomposite interlayer enabled the formation of a smoother and highly separated selective polyamide layer. The separation factor exhibited a 31-fold enhancement with the augmentation of the blending fraction of gCNQDs during the PDA coating process. The resulting TFNi membrane attained an exceedingly high separation factor of 10270 ± 90 with a permeate water concentration of 99.9% and demonstrated a satisfactory flux of 1.40 ± 0.08 kg⋅m-2⋅h-1 during the PV process of 90 wt% IPA dehydration at 60 °C. This study presents a fresh perspective on the implementation of nanocomposite interlayers, which is expected to expand the application of high-performance TFNi membranes in PV dehydration processes.

Microwave-assisted dehydration of strontium hydroxide octahydrate: Experimental study and kinetic modeling analysis

In this context, the present study proposes the use of microwave irradiation to improve the dehydration rate and efficiency of strontium hydroxide octahydrate (Sr(OH)2·8H2O) without introducing contaminants. This study revealed that the use of microwave irradiation to dehydrate Sr(OH)2·8H2O is feasible and surprisingly efficient. The effects of this approach on important parameters were investigated using response surface methodology (RSM). The results revealed that the microwave dehydration process follows a linear polynomial model. In addition, compared with the heating time and material thickness, the microwave-assisted dehydration of Sr(OH)2·8H2O is sensitive to the microwave power and not to the material mass. The relative dehydration percentage reached 99.99% when heated in a microwave oven at 950 W for just 3 min. In contrast, a relative dehydration percentage of 94.6% was reached when heated in an electric furnace at 180 °C for 120 min. The XRD spectra also revealed that most of the Sr(OH)2·8H2O transformed into Sr(OH)2 after dehydration via microwave irradiation, whereas a significant portion of the Sr(OH)2·H2O remained after conventional electric dehydration. The experimental data were fitted and analyzed via the thin-layer drying dynamics model, and the results indicated that the dehydrating behavior of Sr(OH)2·8H2O could be well described by the Page model.