Abstract
Catalytic solvent regeneration has attracted broad interest owing to its potential to reduce energy consumption in CO
2
separation, enabling industry to achieve emission reduction targets of ...the Paris Climate Accord. Despite recent advances, the development of engineered acidic nanocatalysts with unique characteristics remains a challenge. Herein, we establish a strategy to tailor the physicochemical properties of metal-organic frameworks (MOFs) for the synthesis of water-dispersible core-shell nanocatalysts with ease of use. We demonstrate that functionalized nanoclusters (Fe
3
O
4
-COOH) effectively induce missing-linker deficiencies and fabricate mesoporosity during the self-assembly of MOFs. Superacid sites are created by introducing chelating sulfates on the uncoordinated metal clusters, providing high proton donation capability. The obtained nanomaterials drastically reduce the energy consumption of CO
2
capture by 44.7% using only 0.1 wt.% nanocatalyst, which is a ∽10-fold improvement in efficiency compared to heterogeneous catalysts. This research represents a new avenue for the next generation of advanced nanomaterials in catalytic solvent regeneration.
Acid–base copolymer materials are of considerable interest because of their fundamental implications for acid–base bifunctional catalysis applications. However, quenching the acid and base sites of ...the copolymer with each other in free radical polymerizations is still challenging. Herein, we demonstrate that the polymerization of styrenesulfonic acid-co-4-vinylpyridine into the mesoporous carbon material (i.e., CMK-3) can control the chain growth polymerization and result in decreasing the interaction of the acid–base sites. The results showed that by using CMK-3, 40% of the acid and base sites of the copolymer remain in their original form while 60% of acid and base sites convert to the pyridinium and sulfonate forms. Furthermore, it is demonstrated that this material can be processed as a heterogeneous bifunctional acid–base catalyst in the tandem one-pot acid–base reaction (i.e., deacetalization–Knoevenagel condensation reaction) with a high catalytic activity in aqueous media.
Graphic abstract
Aqueous solutions of tertiary amines are promising absorbents for CO2 capture, as they are typically characterized by a high absorption capacity, low heat of reaction, and low corrosivity. However, ...tertiary amines also exhibit very low kinetics of CO2 absorption, which has made them unattractive options for large-scale utilization. Here, a series of novel nanoporous carbonaceous promoters (NCPs) with different properties were synthesized, characterized, and used as rate promoters for CO2 absorption in aqueous N, N-diethylethanolamine (DEEA) solutions. To prepare a DEEA–NCP nanofluid, NCPs were dispersed into aqueous 3 mol·L−1 DEEA solution using ultrasonication. The results revealed that among microporous (GC) and mesoporous (GS) carbonaceous structures functionalized with ethylenediamine (EDA) and polyethyleneimine (PEI) molecules, the GC–EDA promoter exhibited the best performance. A comparison between DEEA–GC–EDA nanofluid and typical aqueous DEEA solutions highlighted that the GC-EDA promoter enhances the rate of CO2 absorption at 40 °C by 38.6% (36.8–50.7 kPa·min−1) and improves the equilibrium CO2 absorption capacity (15 kPa; 40 °C) by 13.2% (0.69–0.78 mol of CO2 per mole of DEEA). Moreover, the recyclability of DEEA–GC–EDA nanofluid was determined and a promotion mechanism is suggested. The outcomes demonstrate that NCP–GC–EDA in tertiary amines is a promising strategy to enhance the rate of CO2 absorption and facilitate their large-scale deployment.
In patients with hepatitis E virus (HEV) infections, extrahepatic, particularly renal and hematological manifestations, are increasingly reported in the medical literature but have never been studied ...compared to a control cohort. We retrospectively analyzed medical records of consecutive patients that were diagnosed with acute hepatitis E (AHE) (n = 69) or acute hepatitis A (AHA) (n = 46) at the University Medical Center Hamburg Eppendorf from January 2009 to August 2019 for demographical, clinical, and laboratory information. Patients with AHE had significantly lower median levels of ALAT (798 U/L) and total bilirubin (1.8 mg/dL) compared to patients with AHA (2326 U/L;
< 0.001 and 5.2 mg/dL;
< 0.001), suggesting a generally less severe hepatitis. In contrast, patients with AHE had significantly higher median serum creatinine levels (0.9 mg/dL vs. 0.8 mg/dL;
= 0.002) and lower median estimated glomerular filtration rate (eGFR) (91 mL/min/1.73 m
vs. 109 mL/min/1.73 m
;
< 0.001) than patients with AHA. Leucocyte, neutrophil and lymphocyte count, hemoglobin, platelets, red cell distribution width (RDW), neutrophil to lymphocyte ratio (NLR), and RDW to lymphocyte ratio (RLR) did not differ between patients with AHE and those with AHA. Our observations indicate that renal but not hematological interference presents an underrecognized extrahepatic feature of AHE, while inflammation of the liver seems to be more severe in AHA.
Ni/mZSM-5 and Ni/H-mZSM-5 were synthesized as hierarchical (micro/meso porous) ZSM-5 zeolites by an indirect template method for the first time. The resulting zeolite materials exhibited ...significantly enhanced diffusional properties in comparison to purely microporous zeolite materials. The structural and morphological characterization of the prepared catalysts was investigated using XRD, BET, atomic absorption spectroscopy, FT-IR,
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Al-MAS NMR, SEM, TEM, XPS and DRS-UV techniques. These hierarchical zeolites were used as acid-metal bi-functional heterogeneous catalysts for hydride transfer in the reduction of nitro aromatic compounds. In these reactions, NaBH
4
was used as a reducing agent. Excellent yields at room temperature and very short reaction times in aqueous media conditions were obtained. Reusability experiments showed the excellent stability of Ni/mZSM-5 and Ni/H-mMZSM-5 and the catalysts could be reused 7 times without much loss of activity in reduction of nitro aromatic compounds. Surprisingly, the acid form of Ni/H-mZSM-5 showed much higher activity than that of Ni/mZSM-5. High yield, short reaction time, green solvent (water), room temperature, no by-product, the easy reusability of catalysts and the low amounts of catalyst required are some of the advantages of these catalysts.
Ni/mZSM-5 hierarchical zeolite and the acidic form of it were prepared as novel bi-functional catalysts which showed excellent activity for reduction of nitro aromatic compounds in aqueous medium at room temperature.
The data presented in this paper are related to the published research article “Development of aqueous-based phase change amino acid solvents for energy-efficient CO2 capture: The role of ...antisolvent” 1. The raw and analyzed data include the equilibrium and kinetics of CO2 absorption, the density and concentration of different CO2-containing species at upper and lower liquid phases, and particle size distribution of solid particles precipitated during CO2 absorption of aqueous and aqueous-based amino acid solvents. In addition, the SEM images of solid precipitates at the end of CO2 absorption are presented. The detailed values of this phase change amino acid solvent are crucial for large-scale implementation of CO2 capture systems with phase change behavior.
In this paper, we wish to report the synthesis and characterization of nickel nanoparticles supported on acidic form of ZSM-5 zeolite (Ni/H-mZSM-5) with microporous/mesoporous hierarchical structure. ...This catalyst was effectively employed as novel acid-metal bi-functional heterogeneous catalyst for direct one-pot reductive amination of aldehydes with nitroarenes in the presence of NaBH4 as a mild reducing agent. Excellent yields at room temperature and short reaction time in aqueous media conditions were obtained.
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•Hierarchical H-mZSM-5 zeolite containing Ni nanoparticles was synthesized.•Ni/H-mZSM-5 was prepared as novel acid-metal bi-functional heterogeneous catalyst.•Ni/H-mZSM-5 was used for one-pot reductive amination of aldehydes with nitroarenes.•Excellent yields at room temperature in water were obtained.•The stability of the catalyst was excellent and could be reused 6 times.
CO2 emissions from industrial processes and their adverse implications on the climate is of major concern. Carbon capture and storage (CCS), especially using chemical-absorption-based processes, has ...been regarded as one of the most realistic pathways to curtail global warming and climate change. However, the energy-intensive nature of CO2 capture and therefore its expensive cost of operation has been regarded as the main barrier halting its widespread implementation among the portfolio of low-carbon energy technologies currently available. Recently, catalytic solvent regeneration has drawn significant attention as a new class of technology for energy-efficient CO2 capture with great potential for large-scale implementation. In this review, recent progress and developments associated with catalyst-aided solvent regeneration for low-temperature energy-efficient CO2 desorption is presented. A detailed discussion of heterogeneous acid–base catalyst is undertaken and the specific privileges, drawbacks, and challenges of each catalyst identified and commented upon. In keeping with the latest investigations, the promotion mechanism of catalytic CO2 desorption and the role of Lewis acids, Brønsted acids, and basic active sites are scrutinized. The performance of solid acid–base catalysts in different primary and blended amine solutions associated with their physicochemical properties is also reviewed. Finally, the status of catalytic solvent regeneration for post-combustion CO2 capture is comprehensively analyzed and a clear pathway for future research investigations is provided.
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•A series of novel GlyK/DMF/H2O solvents was successfully developed for CO2 capture.•NMR spectroscopy was used to identify the species at different phases.•The upper liquid phase of ...developed solvent was free from CO2-containing species.•The heat duty of solvent was reduced by 59.1% compared to the aqueous solvent.
The energy penalty is a primary limitation for the implementation of the aqueous solvents for large-scale post-combustion CO2 capture processes. In this study, a novel aqueous-based phase change solvent, composed of potassium glycinate (GlyK, reactive species), water (H2O, solvent) and dimethylformamide (DMF, antisolvent) was developed to improve the energy efficiency of CO2 capture. To examine the role of the antisolvent, a series of aqueous-based amino acid solvents (GlyK-X) with different DMF:H2O (X) volume ratios was prepared, fully characterized and assessed. It was observed that a CO2-free phase appeared at the top of the aqueous-based amino acid GlyK-X solvents after CO2 absorption which can be easily separated and recycled to the absorption column and save energy. The results showed that the GlyK-60 solvent with DMF:H2O volume ratio of 60:40 had a very high CO2-free phase volume (63%). Moreover, the GlyK-60 solvent exhibited 26.1% (0.433–0.546 mol CO2/mol GlyK) enhancement in CO2 absorption capacity, 38.5% (130–80 min) decrease in regeneration time and 59.1% reduction in relative heat duty compared to the conventional aqueous GlyK solvent. Overall, the outcomes confirmed that the aqueous-based phase change GlyK-60 solvent is a viable solvent option for large-scale CO2 capture with extra-low energy consumption and a key to the success of Paris Climate Accord.
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