A New Method for Preventing Catalytic Degradation of Cotton Cellulose by Ferrous or Ferric Ions During Bleaching with Hydrogen Peroxide

In this paper, we presented a new method for constructing near-infrared fluorescence probes and their applications in detecting glucose and hydrogen peroxide (H2O2).

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Homogeneous oxidation of phenols in aqueous solution with hydrogen peroxide and ferric ions

Water Science & Technology ◽

10.2166/wst.1997.0506 ◽

1997 ◽

Vol 36 (2-3) ◽

pp. 151-154 ◽

Cited By ~ 6

Author(s):

H. Grigoropoulou ◽

C. Philippopoulos

Keyword(s):

Hydrogen Peroxide ◽

Ferrous Sulphate ◽

Ph Control ◽

Chemical Oxidation ◽

Ferric Ions ◽

Experimental Conditions ◽

Oxidation Rates ◽

Homogeneous Oxidation ◽

Oxidation Of Phenol ◽

Ferrous Ammonium

The chemical oxidation of phenol and chlorophenols with hydrogen peroxide in the presence of soluble iron can be economically attractive at low oxidant consumption, leading then to intermediates that are more easily biodegradable. The homogeneous oxidation of phenol and chlorophenols in aqueous solutions with hydrogen peroxide is studied at oxidant : phenol ratio of about 4:1 and 16:1 (mol/mol) at various catalyst concentrations, at ambient temperature without pH control. Ferric chloride, ferric and ferrous sulphate and ferrous ammonium sulphate are used as oxidation catalysts. Ferric salts induce higher oxidation rates than ferrous ones and the nature of the anions present does not affect reaction rate. 4-Chlorophenol is found to be most resistant to oxidation and 2,4,6-Trichlorophenol is not attacked by hydrogen peroxide in the presence of ferric ions at the experimental conditions studied.

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A new method for the preparation of peroxymonophosphoric acid

Canadian Journal of Chemistry ◽

10.1139/v03-010 ◽

2003 ◽

Vol 81 (2) ◽

pp. 156-160 ◽

Cited By ~ 8

Author(s):

Tian Zhu ◽

Hou-min Chang ◽

John F Kadla

Keyword(s):

Hydrogen Peroxide ◽

Acetic Acid ◽

Carbon Tetrachloride ◽

Glacial Acetic Acid ◽

Acid Synthesis ◽

Conversion Ratio ◽

New Method ◽

Phosphorous Pentoxide ◽

Preparation Conditions ◽

Peroxy Acids

A new method for the preparation of peroxymonophosphoric acid (H3PO5) has been developed. It utilizes a biphasic solution to moderate the vigorous reaction between phosphorous pentoxide (P2O5) and hydrogen peroxide (H2O2). P2O5 is suspended in carbon tetrachloride (CCl4), and concentrated H2O2 is slowly added while being vigorously stirred at low temperature. Careful control of the reaction temperature through the slow addition of H2O2 is critical. Using typical preparation conditions (P2O5:H2O2 = 0.5:1, H2O2 70 wt %, 2°C, 120180 min), ~70% of the H2O2 is effectively converted to H3PO5. Increasing the concentration of H2O2, as well as the mole ratio of P2O5:H2O2, leads to an even higher % conversion of H2O2 to H3PO5. The addition of glacial acetic acid to the P2O5:H2O2 suspension at the end of the 120180 min reaction (P2O5:H2O2:CH3COOH = 0.5:1:0.3) leads to the formation of peracetic acid in addition to H3PO5, and to an overall increase in the conversion ratio of total peroxy acids based on H2O2 (>95%).Key words: peroxymonophosphoric acid, synthesis, stability, conversion ratio.

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Collaborative Study of a New Method for the Extraction of Light Filth from Ground Coffee

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/55.1.57 ◽

1972 ◽

Vol 55 (1) ◽

pp. 57-59

Author(s):

Joel J Thrasher

Keyword(s):

Hydrogen Peroxide ◽

Carbon Tetrachloride ◽

Collaborative Study ◽

Mineral Oil ◽

New Method ◽

Official Method ◽

Peroxide Bleaching ◽

Filter Papers ◽

Analytical Time ◽

Ground Coffee

Abstract A collaborative study has been completed on a new method for light filth in ground coffee. The sample is defatted with chloroform, dried, and boiled in water; isopropanol is added and the sample is boiled again. Light filth is trapped off with mineral oil from a hot solution. The method yields better recoveries of insect fragments and rodent hairs than the official method. Other advantages are less analytical time, cleaner filter papers, and elimination of the use of carbon tetrachloride. It is recommended that the method be adopted as official first action to replace 40.007(b) for the isolation of light filth from ground coffee and that the hydrogen peroxide bleaching technique described earlier be adopted as a procedure to replace the sodium hypochlorite technique described in 40.006.

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