scholarly journals Exploring the Thermodynamic Limits of Enhanced H2 Recovery With Inherent Carbon Removal From Low Value Aqueous Biomass Oxygenate Precursors

2021 ◽  
Vol 9 ◽  
Author(s):  
Prince Ochonma ◽  
Claire Blaudeau ◽  
Rosalie Krasnoff ◽  
Greeshma Gadikota
Keyword(s):  
Water Soluble ◽  
Reaction Conditions ◽  
Carbon Removal ◽  
Preferential Formation ◽  
Energy Needs ◽  
Molecular Scale ◽  
Thermodynamic Limits ◽  
H2 Recovery ◽  
Thermodynamic Feasibility ◽  
Ca Carbonate

Rational integration of chemical pathways at the molecular scale to direct thermodynamically favorable enhanced H2 production with inherent carbon removal from low-value substrates can be guided by exploring the thermodynamic limits of feasibility. The substrates of interest are biomass oxygenates that are water-soluble and uneconomical for separation from water. In this study, we investigate the thermodynamic feasibility of recovering H2 with inherent carbon removal from biomass oxygenates such as ethanol, methanol, glycerol, ethylene glycol, acetone, and acetic acid. The influence of biomass oxygenate-to-water ratios, reaction temperature of 150°C–325°C, and CaO or Ca(OH)2 as the alkalinity source on the yields of H2, CH4, CO2, and Ca-carbonate are investigated. By maintaining the fluids in the aqueous phase under pressure, energy needs associated with vaporization are circumvented. The hypothesis that enhanced alkalinity favors the preferential formation of CO (precursor for CO2 formation) over CH4 and aids the formation of calcium carbonate is investigated. The findings from these studies inform the feasibility, design of experiments, and the tuning of reaction conditions for enhanced H2 recovery with inherent carbon removal from biomass oxygenate sources.

scholarly journals Cyclopentadienone Iron Tricarbonyl Complexes-Catalyzed Hydrogen Transfer in Water

Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 421 ◽  
Author(s):  
Daouda Ndiaye ◽  
Sébastien Coufourier ◽  
Mbaye Diagne Mbaye ◽  
Sylvain Gaillard ◽  
Jean-Luc Renaud
Keyword(s):  
Metal Complexes ◽  
Hydrogen Transfer ◽  
Low Cost ◽  
Pure Water ◽  
Free Water ◽  
Water Soluble ◽  
Tricarbonyl Complex ◽  
Reaction Conditions ◽  
Catalytic Systems ◽  
Iron Tricarbonyl

The development of efficient and low-cost catalytic systems is important for the replacement of robust noble metal complexes. The synthesis and application of a stable, phosphine-free, water-soluble cyclopentadienone iron tricarbonyl complex in the reduction of polarized double bonds in pure water is reported. In the presence of cationic bifunctional iron complexes, a variety of alcohols and amines were prepared in good yields under mild reaction conditions.

Spectrofluorimetric Determination of Some Water-Soluble Vitamins

2011 ◽  
Vol 94 (6) ◽  
pp. 1758-1769 ◽  
Author(s):  
Abdel-Maaboud I Mohamed ◽  
Horria A Mohamed ◽  
Niveen M Abdel-Latif ◽  
Marwa R Mohamed
Keyword(s):  
Water Soluble ◽  
Good Precision ◽  
Linear Calibration ◽  
Reaction Conditions ◽  
Pharmaceutical Dosage Forms ◽  
Accuracy And Precision ◽  
Significant Difference ◽  
Spectrofluorimetric Determination ◽  
Comparison Of The Results

Abstract Two simple and sensitive spectrofluorimetric methods were developed for determination of three water-soluble vitamins (B1, B2, and B6) in mixtures in the presence of cyanocobalamin. The first one was for thiamine determination, which depends on the oxidation of thiamine HCl to thiochrome by iodine in an alkaline medium. The method was applied accurately to determine thiamine in binary, ternary, and quaternary mixtures with pyridoxine HCl, riboflavin, and cyanocobalamin without interference. In the second method, riboflavin and pyridoxine HCl were determined fluorimetrically in acetate buffer, pH 6. The three water-soluble vitamins (B1, B2, and B6) were determined spectrofluorimetrically in binary, ternary, and quaternary mixtures in the presence of cyanocobalamin. All variables were studied in order to optimize the reaction conditions. Linear relationship was obeyed for all studied vitamins by the proposed methods at their corresponding λexc or λem. The linear calibration curves were obtained from 10 to 500 ng/mL; the correlation ranged from 0.9991 to 0.9999. The suggested procedures were applied to the analysis of the investigated vitamins in their laboratory-prepared mixtures and pharmaceutical dosage forms from different manufacturers. The RSD range was 0.46–1.02%, which indicates good precision. No interference was observed from common pharmaceutical additives. Good recoveries (97.6 ± 0.7–101.2 ± 0.8%) were obtained. Statistical comparison of the results with reported methods shows excellent agreement and indicates no significant difference in accuracy and precision.

Study on the Synthesis and Properties of Water-Soluble Chitosan Grafted Copolymer

2011 ◽  
Vol 396-398 ◽  
pp. 1480-1485
Author(s):  
Shui Li Lai ◽  
Ning Yang ◽  
Qiang Chai
Keyword(s):  
Light Transmission ◽  
Ammonium Persulfate ◽  
Water Soluble ◽  
Raw Material ◽  
Reaction Conditions ◽  
Grafted Copolymer ◽  
Deacetylation Degree ◽  
Aqueous Solution Polymerization ◽  
Optimum Reaction ◽  
Polymerization Method

Grafted chitosan(CTS) copolymer was synthesized by the aqueous solution polymerization method, using the ammonium persulfate as initiator graft, Acrylamide（AM）and methacrylamide trimethyl Ammonium Chloride (DMC) as the grafted monomer. The effects of reaction conditions on grafted copolymerization were studied. When the deacetylation degree of chitosan as raw material is 86%, the optimum reaction to produce CTS -AM-DMC ternary graft copolymers by first AM and then DMC sequence were obtained at [initiator] 0.08%, 50°Cand 3.5h.The structure of CTS-AM-DMC was characterized by FTIR and XRD. When the dosage of synthetic product is 0.3mg/L, the effect of flocculation on the papermaking wastewater is obvious better, which can make the light transmission up to 99%, and CODCr to 9mg/L.

Synthesis and Performances of Water-Soluble Phenolic Resin

2014 ◽  
Vol 1049-1050 ◽  
pp. 129-132
Author(s):  
Ji Yuan Wu ◽  
Xiao Lin Qian ◽  
Pei Zhi Yu
Keyword(s):  
Phenolic Resin ◽  
Water Solubility ◽  
Water Soluble ◽  
Synthesis Process ◽  
Polymerization Temperature ◽  
Process Conditions ◽  
Polymerization Time ◽  
Reaction Conditions ◽  
Strong Reaction ◽  
Weak Gel

Water-soluble phenolic resin was synthesized via two-step alkaline catalytic reaction. The influences of synthesis process conditions on hydroxymethyl content of water-soluble phenolic resin molecular chain were also studied. The results show that the increase of formaldehyde dosage, as well as the increase of reaction temperature and reaction time, the content of hydromethyl in resin increased first, and then decreased. Without the addition of stabilizer, polymer weak gel for flooding was synthesized with HPAM crosslinked water-soluble phenolic resin. The performance analysis of the weak gel shows that the change of viscosity of weak gel corresponds to the change of the content of hydromethyl in resin. Phenolic resin with good water-solubility and strong reaction ability to HPAM was polymerized and the reaction conditions are as following: phenol and formaldehyde in mol ratio 1:2~1:3, in solution with pH= 9~10, under final condensed polymerization temperature 85°C and in condensed polymerization time 30 minutes.

Novel Templated Polyphenol for Ionic Conductivity

2001 ◽  
Vol 702 ◽  
Author(s):  
Ferdinando F. Bruno ◽  
Ramaswamy Nagarajan ◽  
Jayant Kumar ◽  
Lynne A. Samuelson
Keyword(s):  
Molecular Weight ◽  
Ionic Conductivity ◽  
High Molecular Weight ◽  
Polyethylene Oxide ◽  
Phenol Formaldehyde ◽  
Industrial Applications ◽  
Water Soluble ◽  
Reaction Conditions ◽  
Water Solvent ◽  
Potential Use

ABSTRACTPhenolic polymers and phenol formaldehyde resins are of great interest for a number of electronic and industrial applications. Unfortunately, the toxic nature of the starting materials (formaldehyde) and harsh reaction conditions required for the synthesis of these polymers have severely limited their use in today’s markets. We present here an alternative, biocatalytic approach where the enzyme horseradish peroxidase is used to polymerize phenol in the presence of a template such as polyethylene oxide. Here the template serves as a surfactant that can both emulsify the phenol and polyphenol chains during polymerization and maintain water/solvent solubility of the final polyphenol/template complex. The reactants and the reaction conditions of this approach are mild and result in high molecular weight, electrically and optically active, water-soluble complexes of polyphenol and the template used. High molecular weight water-soluble polyphenol/polyethylene oxide complexes were formed. The ionic conductivity and potential use of these polymers as polyelectrolytes for battery and solution cell applications will be discussed.

scholarly journals Aqueous-biphasic hydroformylation of 1-hexene catalyzed by the complex HCo(CO)[P(o-C6H4SO3Na)]3

2017 ◽  
Vol 61 (2) ◽  
Author(s):  
María Modroño-Alonso ◽  
William Castro ◽  
Francisco Lopez-Linares ◽  
Merlín Rosales ◽  
Pablo Jose Baricelli
Keyword(s):  
Cobalt Complex ◽  
Nitrogen Atmosphere ◽  
Water Soluble ◽  
Catalyst Precursor ◽  
Reaction Conditions ◽  
Moderate Reaction ◽  
H Nmr ◽  
Reductive Carbonylation ◽  
Aqueous Biphasic ◽  
C Nmr

The water soluble cobalt complex HCo(CO)[P(<em>o</em>-C<sub>6</sub>H<sub>4</sub>SO-<sub>3</sub>Na)]<sub>3</sub> was used as catalyst precursor for the biphasic aqueous hydroformylation of 1-hexene. The complex was synthesized by reductive carbonylation of CoCl<sub>2</sub>.6H<sub>2</sub>O in the presence of <em>o</em>-TPPTS ([P(<em>o</em>-C<sub>6</sub>H<sub>4</sub>SO<sub>3</sub>Na)]<sub>3</sub>) under nitrogen atmosphere and characterized by FTIR, <sup>1</sup>H NMR and <sup>31</sup>P {1H} NMR, <sup>13</sup>C NMR, DEPT – 135, COSY, HSQC, MS (ESI). The catalytic activity of the complex in the biphasic hydroformylation reaction of 1-hexene was evaluated under moderate reaction conditions. The pressure and temperature were varied from 4137 – 7584 kPa (600-1100 psi) of syngas and from 353 – 383 K (80 – 110 °C), respectively. The 1-hexene concentration was varied from 0.021-0,11M and the catalyst from 4x10<sup>-4</sup> - 1.1x10<sup>-3</sup> M. The best conversion at 363 K and 7584 kPa and 7.5 h was 62% with selectivity towards aldehydes (heptanal and 2-methyl-hexanal) of 66% to with l/b ratio of 2.6. The recycling of the catalytic precursor after four successive times, did not show any loss on the activity, having selectivity towards aldehyde up to 60%.

scholarly journals Chemical oxidative potential of secondary organic aerosol (SOA) generated from the photooxidation of biogenic and anthropogenic volatile organic compounds

2016 ◽  
Author(s):  
Wing Y. Tuet ◽  
Yunle Chen ◽  
Lu Xu ◽  
Shierly Fok ◽  
Dong Gao ◽  
...  
Keyword(s):  
Health Effects ◽  
Biomass Burning ◽  
Organic Aerosol ◽  
Water Soluble ◽  
Hydrocarbon Emissions ◽  
Reaction Conditions ◽  
Oxidative Potential ◽  
Incomplete Combustion ◽  
Volatile Organic ◽  
Biomass Burning Aerosol

Abstract. Particulate matter (PM), of which a significant fraction is comprised of secondary organic aerosols (SOA), has received considerable attention due to their health implications. In this study, the water-soluble oxidative potential (OPWS) of SOA generated from the photooxidation of biogenic and anthropogenic hydrocarbon precursors (isoprene, α-pinene, β-caryophyllene, pentadecane, m-xylene, and naphthalene) under different reaction conditions (RO2 + HO2/RO2 + NO dominant, dry/humid) was characterized using dithiothreitol (DTT) consumption. The measured intrinsic OPWS-DTT ranged from 9–205 pmol min−1 µg−1 and were highly dependent on the specific hydrocarbon precursor, with naphthalene and isoprene SOA generating the highest and lowest OPWS-DTT, respectively. Humidity and RO2 fate affected OPWS-DTT in a hydrocarbon-specific manner, with naphthalene SOA exhibiting the most pronounced effects, likely due to the formation of nitroaromatics. Together, these results suggest that precursor identity may be more influential than reaction condition in determining SOA health effects, demonstrating the importance of sources, such as incomplete combustion, to aerosol toxicity. In the context of other PM sources, all SOA systems with the exception of naphthalene SOA were less DTT active than ambient sources related to incomplete combustion, including diesel and gasoline combustion as well as biomass burning. Finally, naphthalene SOA was as DTT active as biomass burning aerosol, which was found to be the most DTT active OA source in a previous ambient study. These results highlight a need to consider SOA contributions (particularly from anthropogenic hydrocarbons) to health effects in the context of hydrocarbon emissions, SOA yields, and other PM sources.

scholarly journals Chemical oxidative potential of secondary organic aerosol (SOA) generated from the photooxidation of biogenic and anthropogenic volatile organic compounds

2017 ◽  
Vol 17 (2) ◽  
pp. 839-853 ◽  
Author(s):  
Wing Y. Tuet ◽  
Yunle Chen ◽  
Lu Xu ◽  
Shierly Fok ◽  
Dong Gao ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Organic Aerosol ◽  
Water Soluble ◽  
Hydrocarbon Emissions ◽  
Reaction Conditions ◽  
Oxidative Potential ◽  
Incomplete Combustion ◽  
Volatile Organic ◽  
Specific Manner ◽  
Biomass Burning Aerosol

Abstract. Particulate matter (PM), of which a significant fraction is comprised of secondary organic aerosols (SOA), has received considerable attention due to its health implications. In this study, the water-soluble oxidative potential (OPWS) of SOA generated from the photooxidation of biogenic and anthropogenic hydrocarbon precursors (isoprene, α-pinene, β-caryophyllene, pentadecane, m-xylene, and naphthalene) under different reaction conditions (RO2+ HO2 vs. RO2+ NO dominant, dry vs. humid) was characterized using dithiothreitol (DTT) consumption. The measured intrinsic OPWS-DTT values ranged from 9 to 205 pmol min−1 µg−1 and were highly dependent on the specific hydrocarbon precursor, with naphthalene and isoprene SOA generating the highest and lowest OPWS-DTT values, respectively. Humidity and RO2 fate affected OPWS-DTT in a hydrocarbon-specific manner, with naphthalene SOA exhibiting the most pronounced effects, likely due to the formation of nitroaromatics. Together, these results suggest that precursor identity may be more influential than reaction condition in determining SOA oxidative potential, demonstrating the importance of sources, such as incomplete combustion, to aerosol toxicity. In the context of other PM sources, all SOA systems, with the exception of naphthalene SOA, were less DTT active than ambient sources related to incomplete combustion, including diesel and gasoline combustion as well as biomass burning. Finally, naphthalene SOA was as DTT active as biomass burning aerosol, which was found to be the most DTT-active OA source in a previous ambient study. These results highlight a need to consider SOA contributions (particularly from anthropogenic hydrocarbons) to health effects in the context of hydrocarbon emissions, SOA yields, and other PM sources.

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