Hydroquinone Oxidation for the Detection of Catalytic Activity in Liquid Chromatographic Columns

Jeng, Chawn-Ying; Langer, Stanley H.

doi:10.1093/chromsci/27.9.549

Cited by 12 publications

(5 citation statements)

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“…Further increase in the concentration was found to have little effect on mercury re-emission. McKillop et al and Zheng et al reported that hydroquinone could reduce oxidized mercury into elemental mercury (Hg 0 ), and many researchers − also suggested that hydroquinone could be oxidized to generate p -benzoquinone (C 6 H 4 O 2 ). Therefore, the increase of mercury re-emission in the presence of hydroquinone could be ascribed to its reduction effect, and the possible reduction process as follows: …”

Section: Resultsmentioning

confidence: 99%

Mercury Re-emission Behaviors in Magnesium-Based Wet Flue Gas Desulfurization Process: The Effects of Oxidation Inhibitors

et al. 2015

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The effects of four oxidation inhibitors (including ascorbic acid, formaldehyde, hydroquinone, and sodium thiosulfate) on mercury re-emission in simulated magnesium-based wet flue gas desulfurization solution were evaluated. Experimental results demonstrated that the addition of ascorbic acid significantly increased the mercury re-emission, whereas the formaldehyde and hydroquinone could slightly enhance this process at pH 6. Sodium thiosulfate was found to somewhat inhibit the bivalent mercury reduction owing to the strong binding between mercury and thiosulfate ions. pH variation showed dramatic effects on elemental mercury re-emission in the solution containing ascorbic acid or hydroquinone, and the mercury emission amount in 30 min increased about seven-and two-fold, respectively, when pH was adjusted from 6 to 8. These findings indicated that the ascorbic acid was an important reducer of mercury re-emission under acidic condition besides the sulfite ions, whereas it was the main reducer of mercury reduction under alkaline condition. In addition, the investigation on the effects of temperature and the presence of Cl − ions suggested that the mercury re-emission would be accelerated at elevated temperatures and could be suppressed in the presence of Cl − ions.

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Section: Resultsmentioning

confidence: 99%

Mercury Re-emission Behaviors in Magnesium-Based Wet Flue Gas Desulfurization Process: The Effects of Oxidation Inhibitors

et al. 2015

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“…i.d.) between the injector and the detector were of PEEK material (polyether ether ketone; Upchurch) to minimize any metal leaching into the column of the type that might originate from conventional stainless steel material (Jeng and Langer, 1989). A Hewlett-Packard 3396A integrator equipped with a 9114A Disc Drive was used to store reactor chromatogram signals at the acquisition rate of 20 points/s for subsequent data analysis.…”

Section: Methodsmentioning

confidence: 99%

“…sition-metal ions associating with silica (Jeng and Langer, 1989). Since the transport and kinetic properties of the species involved in this reaction seemed suitable for LCR kinetic investigations, this oxidation catalyzed by iron (Fe3+)-modified silica packing in an organic solvent environment is chosen here for exploring and illustrating the application of a general statistical moment approach to liquid chromatographic reactors.…”

Section: Introductionmentioning

confidence: 99%

Rate process analysis in the liquid chromatographic reactor: an application of the first statistical moment

Jeng¹,

Langer²

1991

Ind. Eng. Chem. Res.

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“…The existence of active sites can be proved if decreasing the flow rate leads to increasing product peaks. The positions of the active sites can be determined by reversing the direction of flow [119]. The distribution function of active sites on a catalytic surface can be determined using stopped flow chromatography [120].…”

Section: Characterization Of the Stationary Phasementioning

confidence: 99%

Chromatographic Reactors

Fricke¹,

Schmidt–Traub²,

Schembecker³

2008

Ullmann's Encyclopedia of Industrial Chemistry

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Chromatographic reactors integrate chemical reaction and chromatographic separation in one apparatus. This offers potential for process intensification, especially in the case of equilibrium reactions. Different types of discontinuous and continuous processes as well as modeling of chromatographic reactors are described. Synthesis and design of this processes is very much influenced and often restricted by the type of reaction and the operating window which is set by the individual operating conditions for chemical reaction, mass separation, and equipment design. Integrated chromatographic reactors should be considered if chromatography is the favored separation process for a conventional sequential process design. Preparative chromatographic reactors are known for liquid‐ and gas‐phase processes. Laboratory‐scale applications are described. Analytical chromatographic reactors are used to determine reaction rate constants and kinetics, and to screen chromatographic systems and operating conditions for preparative applications. 1. Introduction 2. Types of Chromatographic Reactors 3. Modeling of Chromatographic Reactors 3.1. Adsorption Isotherm and Reaction Kinetics 3.2. Modeling the BCR 3.3. Modeling Simulated Moving Bed Chromatographic Reactors 3.4. Process control 4. Synthesis of Preparative Chromatographic Reactors 4.1. Process Principles 4.2. Type of Reaction 5. Design of Preparative Chromatographic Reactors 5.1. Design of the Process 5.2. Choice of Operating Conditions 6. Preparative Chromatographic Reactors 6.1. Applications of Gas Chromatographic Reactors 6.2. Application of Liquid Chromatographic Reactors 7. Analytical Chromatographic Reactors 7.1. Determination of Rate Constants 7.2. Enzymatic Reactions 7.3. Characterization of the Stationary Phase 7.4. Examination of Fast Equilibrium Reactions 7.5. Examination of Solvent Effects

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Hydroquinone Oxidation for the Detection of Catalytic Activity in Liquid Chromatographic Columns

Cited by 12 publications

References 0 publications

Mercury Re-emission Behaviors in Magnesium-Based Wet Flue Gas Desulfurization Process: The Effects of Oxidation Inhibitors

Mercury Re-emission Behaviors in Magnesium-Based Wet Flue Gas Desulfurization Process: The Effects of Oxidation Inhibitors

Rate process analysis in the liquid chromatographic reactor: an application of the first statistical moment

Chromatographic Reactors

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