Dehydration Of 1-butanol Research Articles

Spherical nucleic acid nanoprobes for in situ and multiplex detection of exosomal PIWI-interacting RNAs

PIWI-interacting RNAs (piRNAs) are a novel class of non-coding RNAs that bind specifically to the PIWI subfamily of Argonaut proteins. It has been increasingly demonstrated that piRNAs encased in circulating exosomes could be an ample source of potential tumor markers for cancer diagnostics. However, methods on exosomal piRNAs detections are limited, and most of them need extraction of piRNAs from the sample which is laborious and disadvantage to clinical applications. Herein, we developed two kinds of dual-targeted spherical nucleic acid nanoprobes for in situ and multiplex detection of exosomal piRNAs. The detection scheme was rationally designed for the large sized targets of PIWI-interacting RNA complex which could generate steric hindrance in the detection reaction. The probes were synthesized by modifying 13-nm gold particles with high-density double stranded anchor-report DNA through butanol dehydration method. The key synthesis condition of molar ratio between the two kinds of anchor-report DNA chains were optimized for preparing probes with good structural reproducibility. The probes can perform in situ and multiplex detection of piRNAs in exosomes after simple incubation. In the clinical assays of plasma from breast cancer patients and normal control groups, the probes can differentiate the expression levels of 3 types of piRNAs and their combinations in high specificity and sensitivity. These new piRNA probes are potentially to perform simple and accurate liquid biopsy for cancer diagnostics.

Tailoring the interlayer channel structure of graphene oxide membrane with conjugated cationic dyes for butanol dehydration

For the design of high-performance GO membrane, the structure of intercalation material is a key consideration due to its decisive impacts on nanosheet assembly and mass transfer channel structure. Herein, conjugated cationic dyes were incorporated into GO interlayer channels. The large π-conjugated structure and delocalized positive charge can form π-π and electrostatic interactions with the non-oxidized region and negatively-charged group on GO nanosheet, respectively. Through interlayer cross-linking, the nanosheet orientation and interlayer bonding can be improved, conferring the membrane with higher anti-swelling capacity, more ordered channel structure, and controllably tailored interlayer d-spacing. The electron cloud density and planar structure of cationic dye molecules are evidenced to be critical in influencing membrane structure and separation performance. After incorporating conjugated cationic dyes, the separation factor for water/butanol separation can reach 5.3 times of that of pristine GO membrane, while the permeate flux also increases by 20%. This work provides a category of promising intercalation materials for GO membranes with good potential application in butanol dehydration.

A sodium-dependent split DNAzyme fluorescent sensor under butanol acceleration for ultrasensitive detection of PIWI-interacting RNAs and microRNAs

Split DNAzymes have been designed as multifunctional biosensors. However, their limited sensitivity and low resistance to nuclease hinder their applications in biological samples. Herein, we developed a sodium-dependent and butanol accelerated split DNAzyme fluorescent sensor named Na+-BAS DNAzyme which has an ultra-sensitivity for quantifying PIWI-interacting RNAs/microRNAs and can be directly applied in blood biopsy to detect nucleic acids within the extracellular vesicles (EVs). The Na+-BAS DNAzyme consists of two split DNA strands based on NaA43 DNAzyme, a starting hairpin DNA for binding target to initiate the combining of the split enzymes, and a hairpin RNA-embedded DNA substrate labeled a quencher and a fluorophore for signal readout after its cleavage by the assembled DNAzyme complex. To achieve ultra-sensitivity, we employed a simple but key approach of butanol dehydration to highly accelerate the measuring reaction. The sensor has achieved an ultra-low detection limit of 12 × 10−18 M miR-21 after 30 min reaction, and 3.98 or 2.69 particles μL−1 MCF-7 EVs through miR-21 or piR-20365 detection. With these high performances, the sensor can detect extremely trace abundance of miR-21 in a single MCF-10a or MCF-7 EV, quantifying it as 5.93 × 10−3 or 0.12 copies per EV. Without any chemical structure modification, the sensor can be directly used in the plasma sample for breast cancer diagnosis which has obtained both 100% sensitivity and specificity using the biomarker of piR-20365. The Na+-BAS DNAzyme sensor’s ultra-sensitivity, high efficiency, universality, and simplicity make it a great potential in the clinical diagnostic application.

Understanding the dehydration of acetone, 1-butanol, and ethanol fermentation-based biofuel

ABSTRACT Removing most of the water in the acetone + n-butanol + ethanol (ABE fermentation broth can reduce energy consumption and improve the biobutanol market competitiveness. Understanding the dehydration process of ethanol, acetone, and n-butanol can guide the fermentation process for the subsequent separation, which led to an investigation into the salting-out effects of K2CO3 on aqueous ethanol solution, aqueous acetone solution and n-butanol+water system at various temperatures. Elevating the salt concentration has the potential to decrease the water content of these solutes as well as the content of ethanol or acetone and n-butanol in the salt-free aqueous phase. The distribution and selectivity coefficients of ABE were also enhanced. As a result, the recovery and dehydration ratio of ethanol or acetone, or n-butanol, was also improved. The strong hydrophilicity of acetone and ethanol makes the recovery and dehydration ratio of n-butanol difficult. On the same basis(50% K2CO3), the dehydration ratios of ethanol, acetone, and n-butanol were 91.43%, 96.21%, and 97.52%, respectively. Thus, the dehydration capacity gave the following trend: n-butanol>acetone>ethanol. By raising the temperature，it was possible to increase the amount of ethanol，acetone，or n-butanol in the organic phase while decreasing their amounts in the aqueous phase. The ratio of n-butanol’s recovery and dehydration can be improved by raising the temperature.

Comparison of DNA-Gold Nanoparticle Conjugation Methods: Application in Lateral Flow Nucleic Acid Biosensors.

Lateral flow nucleic acid biosensors (LFNABs) have attracted extensive attention due to their rapid turnaround time, low cost, and results that are visible to the naked eye. One of the key steps to develop LFNABs is to prepare DNA-gold nanoparticle (DNA-AuNP) conjugates, which affect the sensitivity of LFNABs significantly. To date, various conjugation methods-including the salt-aging method, microwave-assisted dry heating method, freeze-thaw method, low-pH method, and butanol dehydration method-have been reported to prepare DNA-AuNP conjugates. In this study, we conducted a comparative analysis of the analytical performances of LFNABs prepared with the above five conjugation methods, and we found that the butanol dehydration method gave the lowest detection limit. After systematic optimization, the LFNAB prepared with the butanol dehydration method had a detection limit of 5 pM for single-strand DNA, which is 100 times lower than that of the salt-aging method. The as-prepared LFNAB was applied to detect miRNA-21 in human serum, with satisfactory results. The butanol dehydration method thus offers a rapid conjugation approach to prepare DNA-AuNP conjugates for LFNABs, and it can also be extended to other types of DNA biosensors and biomedical applications.

1-Butanol dehydration and oxidation over vanadium phosphate catalysts

The transformation of 1-butanol into either butenes or maleic anhydride was carried out both with and without oxygen, using V/P/O catalysts. With vanadyl pyrophosphate prepared by coprecipitation, at temperature lower than 240 °C and without oxygen, selectivity to butenes was higher than 90%, but a slow deactivation took place. At temperature higher than 300 °C and in the presence of air, maleic and phthalic anhydrides were the prevailing products, with selectivity of 60% and 14%, respectively. Catalytic performance was affected by crystallinity and acidity. αI-VOPO4 showed a poor performance in the absence of air, with a quick deactivation due to coke accumulation; but it displayed an excellent selectivity to butenes (close to 98%) at temperatures lower than 320 °C in the presence of air, with stable performance. At temperature higher than 360 °C, α I-VOPO4 was reduced to vanadyl pyrophosphate and catalyzed the direct oxidation of 1-butanol into maleic anhydride, but with 35% selectivity.

Synergistically tailoring the hierarchical channel structure of graphene oxide membrane through co-assembly strategy for high-performance butanol dehydration

A significant boost in permeate flux along with the desirable separation factor remains a challenging issue for graphene oxide (GO) membranes in pervaporation applications. Herein, a facile approach of co-assembling pristine and etched GO nanosheets was proposed to tailor the hierarchical channel structure (involving the slits, defects and interlayer galleries) of GO membrane and achieve remarkable improvements in both the permeate flux and water/butanol separation factor. Pristine GO nanosheets guarantee a defect-free membrane structure, while etched GO (eGO) provides abundant defects/slits for molecular transport, thus reducing molecular diffusion resistance and doubling permeate flux. The introduction of eGO confers a more ordered nanosheet assembly and narrower interlayer spacing, thus strengthening the size-exclusion effect of the interlayer channels towards butanol molecules and realizing a 3-times enhancement in the separation factor. The subsequent intercalation of Congo red (CR) molecules ulteriorly optimizes the interlayer channels and results in the superior water/butanol separation factor of 5705 with the permeate flux of 4.81 kg/(m2h). This work provides a facile and feasible method for constructing high-performance GO-based membranes with great potential for practical butanol dehydration process.

Production of Butane from Methyl Ethyl Ketone over Pt/Al2O3

Methyl ethyl ketone (MEK) was catalytically converted to butane directly in one step over platinum (Pt) supported on alumina (Al2O3). The reaction was performed in the gas phase in a fixed bed reactor. Conversion of MEK to butane was achieved by hydrogenation of MEK to 2-butanol, dehydration of 2-butanol to butene, and further hydrogenation of butene to butane. The results showed that butane can be produced with selectivity reaching 95% depending on the operating conditions. The highest selectivity for butane was obtained at 220 °C and a H2/MEK molar ratio of 15. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Graphite supported heteropolyacid as a regenerable catalyst in the dehydration of 1-butanol to butenes

1-butanol dehydration reaction has recently emerged as a sustainable route to produce butenes which can be further oligomerized to be applied as jet fuel. However, the high catalyst deactivation rates observed during this reaction due to coke deposition is still a pending matter. As promising catalysts for this reaction, we have supported two heteropolyacids (HPA), i.e. H4SiW12O40 (STA) and H3PW12O40 (TPA), on two commercial carbon materials: an activated carbon (AC) and a high surface area graphite (HSAG). Aiming to evaluate the role of HPA-support interactions, the STA was also dispersed over metallic oxides of different acidic nature, namely SiO2, Al2O3 and ZrO2. An exhaustive physicochemical characterization revealed that after the HPA dispersion thorough the support, the Keggin structure was maintained and an increase in the amount and strength of acid sites was provoked, but in different degree according to the HPA type and support’s nature. While the TPA-based catalysts developed less quantity of total acid sites, but higher strength than their STA-carbon counterparts, the STA/AC and TPA/AC samples exhibited a slight major amount of acid sites than STA/HSAG and TPA/HSAG. The HPA-support interactions have ultimately modulated to some extent the activity, selectivity, stability and regeneration ability of the synthesized catalysts, when applied in the gas phase butanol dehydration reaction at 275 °C. The higher STA decomposition temperature prompted by the graphitic support, among other factors, allowed the total regeneration of the highly active (39 mmolBuOH∙min−1∙ga.p) and n-butenes selective (>98 %) STA/HSAG catalyst by means of combustion of carbon deposits at 400 °C.

Self-converted fabrication of a Ni-MOF-74 tubular membrane from nickel-based nanosheets for butanol dehydration by pervaporation

A high-quality Ni-MOF-74 tubular membrane was prepared by the self-conversion of the nickel-based nanosheet layer (Ni-NSL) showing superior pervaporation separation of n-butanol.

Exploring the potential of highly selective deep eutectic solvents (DES) based membranes for dehydration of butanol via pervaporation

N-butanol has unique physicochemical and combustion properties, similar to gasoline, which makes it an environmentally friendly alternative to conventional fuels. To improve the efficiency, the dehydration of butanol is necessary. This paper aims to investigate the performance of Deep Eutectic Solvents (DESs) based membranes for the dehydration of n-butanol by the pervaporation process. Three DES with different combinations of hydrogen bond donors and acceptors, i.e., DL-menthol: Lauric acid (DES), DL-menthol-Palmitic acid (DES), and [TETA] Cl: Thymol (DES), were used. We hypothesized that (i) incorporation of hydrophobic DES would increase the hydrophobicity of the membranes; (ii) specific functional groups (phenolic group, amine group) in DESs would enhance the butanol-philic character of membranes, and (iii) hydrophobic DESs would increase the butanol separation efficiency and permeability of membranes. FTIR analysis and physicochemical parameters of the resultant liquid mixture validated the DESs' production. The DESs were then filled into the permeable support, resulting in supported liquid membranes (SLMs). An additional layer of polydimethylsiloxane (PDMS) was coated directly on the DES-PSf layer to prevent leaching out of DES. A feed containing a 6 wt % aqueous solution of butanol under varying temperatures was studied. The results showed that among all membranes, [TETA] Cl: Thymol DES-based membrane showed the highest sorption of 36% at room temperature. The introduction of DES in membranes resulted in a remarkable increase in the separation factor while sustaining a reasonable flux. Among all the membranes, the DL-menthol: Lauric acid (DES) based membrane exhibited the highest separation factor of 57 with a total flux of 0.11 kg/m2. h. Significantly high butanol-water separation was attributed to the low viscosity and high butanol solubility of the chosen DES, which makes it a suitable substitute to conventional ILs.

Highly accelerated isothermal nucleic acid amplifications by butanol dehydration: simple, more efficient, and ultrasensitive.

Enzyme-free isothermal amplification reactions for nucleic acid analysis usually take several hours to obtain sufficient detection sensitivity, which limits their practical applications. Herein, we report a butanol dehydration-based method to greatly improve both the efficiency and the sensitivity of nucleic acid detections by three types of enzyme-free isothermal amplification reactions. The reaction time has been shortened from 3 h to 5-20 min with higher sensitivities. Especially in the DNAzyme-based amplification, the detection limit can be lowered over 16 000-fold to 3 × 10-17 mol L-1 in 2 h compared to the normal 3 h-reaction. We demonstrate that the high amplification efficiencies are attributed to the greatly accelerated reaction rates in the extremely concentrated reaction solutions caused by the butanol dehydration. This approach enhances the potential of applications of isothermal amplification reactions in clinical rapid tests, nanostructure synthesis, etc. and is promising to expand to other types of chemical reactions.

Process-oriented approach towards catalyst design and optimisation

Translation of catalysts developed in academia to industrial end-users remains a challenge due to a lack of knowledge about the impact of catalyst attributes on the whole process and vice versa. A systematic methodology is proposed that assesses these in terms of Key Performance Indicators (KPIs). As a case study, the dehydration of butanol to butenes and dibutyl ether is considered over H-ZSM5 and H-Beta catalysts. It is demonstrated that catalysts should be designed for complete conversion and high butene selectivity, as removal of unreacted 1-butanol requires a complex separation due to the thermo-physical properties of the product mixture.

Selective dehydration of 1-butanol to butenes over silica supported heteropolyacid catalysts: Mechanistic aspect

Butenes are considered as important olefinic building block to produce fuels/fuel additives and commodity chemicals. In the present investigation, selective dehydration of 1-butanol to butenes was studied in a continuous-flow fixed-bed reactor using various silica-supported heteropolyacid (HPA) catalysts such as phosphotungstic acid (PTA), silicotungstic acid (STA), phosphomolybdic acid (PMA), and silicomolybdic acid (SMA) as the solid acid catalysts. The physicochemical properties of these HPA were determined by BET, powder XRD, FTIR, NH3-TPD, and Py-FTIR. The acid strength and Brønsted/Lewis (B/L) acid ratio were increased with higher loading of HPA on silica. The nature of HPA (addenda and hetero atom) and loading of HPA are important factors for the dehydration of 1-butanol and selectivity towards butenes. PTA and STA showed superior catalytic activity than PMA and SMA. The reaction temperature and WHSV also strongly affected the butanol conversion and selectivity of butenes. The selectivity of di-n‑butyl ether decreases with the rising temperature from 523 K to 623 K. The isomerization of 1-butene leading to the formation of other butene isomers depends on the HPA loading, temperature, and WHSV. The presence of molybdenum addendum atom in PMA and SMA promotes dehydrogenation and hydrogenation, leading to the formation of various light hydrocarbons. The 20PTA/SiO2 catalyst afforded 99.8% selectivity towards butenes at quantitative conversion of 1-butanol, whereas the 20STA/SiO2 catalyst gave nearly 97.0% conversion of 1-butanol and 99.9% butenes selectivity at 673 K, 37.4 h−1 of WHSV.

Modulation of DNAzyme Activity via Butanol Dehydration.

Understanding the activity of biomolecules in cosolvent systems is important for catalysis, separation and developing biosensors. The majority of previously studied solvents are either phase separated with water or miscible with water. Butanol was recently used to extract water for the conjugation of DNA to gold nanoparticles. In this work, the effect of butanol on the activity of a few RNA-cleaving DNAzymes was studied. A 130-fold improvement in sensitivity for the Na+ -specific EtNa DNAzyme was observed, and butanol also improved the activity of another Na+ -specific DNAzyme, NaA43T by a few folds. However, when divalent metal ions were used for both EtNa and 17E DNAzymes, the activity was inhibited. A main driven force for enhanced DNAzyme activity is the concentration effect due to butanol dehydration. This study provides insights into the interplay between DNA, metal ions and organic solvents, and such an understanding might be useful for developing sensitive biosensors.

Chitosan/sodium alginate hybrid membranes modified by zeolitic imidazolate framework-90 for pervaporative dehydration of butanol

Chitosan/sodium alginate hybrid membranes modified by zeolitic imidazolate framework-90 for pervaporative dehydration of butanol

Graphene oxide membranes tuned by metal-phytic acid coordination complex for butanol dehydration

For two-dimensional (2D) lamellar graphene oxide (GO) membranes, tuning the interlayer distance and enhancing surface hydrophilicity are two efficient strategies to achieve high selectivity and permeation flux for solvent dehydration. Herein, Fe3+-phytic acid (PA) coordination complex was designed as both the intercalator and surface modifier to fabricate hydrophilic GO membranes. Fe3+-PA complexes interacted with the oxygen-containing functional groups of GO nanosheets through non-covalent interactions to fix the interlayer distances to 0.61 nm in 90 wt% n-butanol/water mixture.Moreover, Fe3+-PA complexes enhanced the surface hydrophilicity of GO membranes, which promoted the water sorption ability of the membrane and facilitated the fast water-transport. The pervaporation n-butanol dehydration performance was investigated as a function of Fe3+-PA complex content and feed temperature. GO-PA-Fe3+/PTFE membranes with an optimized PA addition amount of 50 wt% exhibited a separation factor of 1059 and a permeation flux of 10.57 kg/(m2 h) under 80 °C for 90 wt% n-butanol/water mixture. This study provides a novel avenue to fabricating 2D lamellar separation membranes by incorporating multifunctional metal-coordinated complexes.

Modeling of Fixed‐Bed Rapid Temperature Swing Adsorber for Butanol Dehydration

AbstractA fixed‐bed system of rapid temperature swing adsorption (RTSA), which uses a solid absorbent for dehydration of butanol, was studied. The packed bed was simulated using proper partial and algebraic equations which were solved by the central difference method in MATLAB software. The equilibrium relationship and fixed‐bed breakthrough curves were determined experimentally. The value of unknown parameters such as equilibrium constants, liquid film mass transfer coefficient, intraparticle diffusion coefficient, and axial diffusivity were estimated by appropriate equations. The model fitted well to experimental breakthrough data. The results proved that it would be possible to operate a complete RSTA cycle in just a few hours to allow a large quantity of organic solvent dehydrated with reasonable concentration.

Promoting the Effect of Au on the Selective Hydrogenolysis of Glycerol to 1,3-Propanediol over the Pt/WOx/Al2O3 Catalyst

The selective hydrogenolysis of glycerol to 1,3-propanediol (1,3-PDO) is an important yet challenging reaction because it requires the selective cleavage of the sterically hindered secondary C–O bond of glycerol. In this work, we have developed a new catalyst, 0.1Au-2Pt/7.5W/Al, which affords both high glycerol conversion (77.5%) and 1,3-PDO selectivity (54.8%), which are significantly higher than the Au-free counterpart. HAADF-STEM reveals that the structure of 0.1Au-2Pt/7.5W/Al is characterized with ∼2 nm Pt NPs decorated with Au-WOₓ at the periphery, where the Au additive exists most likely as single atoms. Chemisorption and XPS show that the electron transfer from W to Au can help to weaken the strong metal support interaction (SMSI) between Pt and WOₓ, and thus greatly enlarges the exposed Pt surface and increases the H-spillover capacity. The 2-butanol dehydration in H₂ reveals that the H-spillover capacity is proportional to the number of Bronsted acid sites, which, in conjunction with the only water desorption in H₂-TPD results, strongly suggests that the active sites for breaking the secondary C–O bond of glycerol should be Bronsted acid sites generated by the H-spillover at the interface between Pt and WOₓ, and the modification by the Au additive increases the number of interfacial sites, and thus enhances the 1,3-PDO yield.

Tannin-based thin-film composite membranes integrated with nitrogen-doped graphene quantum dots for butanol dehydration through pervaporation

A thin-film composite membrane was prepared through the interfacial polymerization of tannic acid (TA), a natural oligomer, and acyl chloride monomers – terephthaloyl chloride (TPC) or trimesoyl chloride (TMC). Thin-film nanocomposite (TFN) membranes were also prepared by loading a new class of carbon nanoparticles – nitrogen-doped graphene quantum dots (NGQDs). The composite membranes were characterized with ATR-FTIR, XPS, SEM and water contact angle. The TA-TMC membrane provided lower flux and better water permselectivity than those prepared with TA-TPC due to availability of more reactive acyl chloride. The concentrations of each reactant used, appropriate loading amount of NGQD and contact time between TA and acyl chloride monomers were all determined and investigated to separate 90/10 wt% n-butanol/water mixture at 25 °C. The TA-TMC was found to have higher surface hydrophilicity due to more hydroxyl groups present. The incorporation of 50 ppm NGQD during the interfacial polymerization enhanced the pervaporation performance by providing additional hydrophilicity and mass transfer resistance to larger permeating molecule. The TA0.075-TMC0.4-NGQD(50) membrane at 3-min contact time had a total flux of 1100 g m−2 h−1 and a water concentration in permeate of 97.1 wt% compared to TA0.075-TPC0.4-NGQD(50) membrane with 2196 g m−2 h−1 and 93.2 wt% in separating 90/10 wt% n-butanol/water mixture at 25 °C. The water permselectivity was also found to be more efficient for isobutanol/water mixtures due to the sterically hindered structure of the alcohol. Furthermore, the TA0.075-TMC0.4-NGQD(50) membrane was also tested to separate all butanol isomer/water mixtures at 25 °C showing better separation performance for sterically hindered or branched butanol isomer. The membrane fabricated herein shows the potential use of cheap and natural oligomer (TA) to produce thin-film composite membranes that provided enough barrier to separate butanol from water through pervaporation.