Photodegradation of cresol red by a non-iron Fenton process under UV and sunlight irradiation: Effect of the copper(II)-organic acid complex activated by H2O2

Laboratories consume great amounts of hazardous chemicals substances and consequently generate wastewater containing them, for example formaldehyde. This substance is widely utilized to preserve biological samples generating many liters of this residue every year. The present work proposes the use of the photo-Fenton process to treat formaldehyde wastewater using sunlight irradiation. Some aspects were investigated such as the iron source, sample and hydrogen peroxide concentration and also the use of stirred systems. The use of ferrioxalate (0.5 mmol L-1) improved the efficiency of the process in relation to the use of iron nitrate, while at least 1.0 mol L-1 H2O2 is necessary to treat the sample of the 500 mg C L-1. Under these conditions, every formaldehyde detectable was degradeted and 89% of the dissolved organic carbon was removed in two hours of exposure to sunlight. These results are satisfaction considerate for São Paulo State Environmental Agency.

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Surface Chemistry of Carbon Black. Effect on Vulcanization of Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3539460 ◽

1935 ◽

Vol 8 (3) ◽

pp. 483-498

Author(s):

Frank K. Schoenfeld

Keyword(s):

Carbon Black ◽

Organic Acids ◽

Surface Chemistry ◽

Organic Acid ◽

Experimental Evidence ◽

Acid Complex ◽

Adsorption Theory ◽

Rubber Compounds

Abstract In an attempt to develop a theory for the retardation of the rate of cure of rubber stocks by carbon black the adsorption theory is critically reviewed. Experimental evidence is presented that is not readily explainable on the basis of this theory. It is shown that the retarding action of gas black is analogous to the action of organic acid retarders of cure. The mechanism of this action is unknown. Gas black activatedly adsorbs oxygen to form an acid complex that retards the cure of rubber compounds. Organic acids have been obtained from commercial blacks by washing with alkalies.

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Photo-Fenton process under sunlight irradiation for textile wastewater degradation: monitoring of residual hydrogen peroxide by spectrophotometric method and modeling artificial neural network models to predict treatment

Chemical Papers ◽

10.1007/s11696-020-01449-y ◽

2021 ◽

Author(s):

Rayany M. R. Santana ◽

Daniella C. Napoleão ◽

Sérgio G. dos Santos Júnior ◽

Rayssa K. M. Gomes ◽

Nathália F. S. de Moraes ◽

...

Keyword(s):

Neural Network ◽

Hydrogen Peroxide ◽

Network Models ◽

Textile Wastewater ◽

Fenton Process ◽

Neural Network Models ◽

Sunlight Irradiation ◽

Residual Hydrogen ◽

Degradation Monitoring ◽

Artificial Neural Network Models

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A green solar photo-Fenton process for the degradation of carbamazepine using natural pyrite and organic acid with in-situ generated H2O2

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.147187 ◽

2021 ◽

pp. 147187

Author(s):

Qian Guo ◽

Wenjie Zhu ◽

Daoli Yang ◽

Xi Wang ◽

Yinghao Li ◽

...

Keyword(s):

Organic Acid ◽

Fenton Process ◽

Natural Pyrite

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Photo-Fenton process for treating biological laboratory wastewater containing formaldehyde

Eclética Química ◽

10.1590/s0100-46702010000100003 ◽

2010 ◽

Vol 35 (1) ◽

pp. 25-33

Author(s):

Janaína Conrado L. Fonseca ◽

Raquel F. Pupo Nogueira ◽

Mary Rosa Rodrigues Marchi

Keyword(s):

Hydrogen Peroxide ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Biological Samples ◽

Iron Nitrate ◽

Fenton Process ◽

Sunlight Irradiation ◽

Paulo State ◽

Source Sample ◽

Environmental Agency

Laboratories consume great amounts of hazardous chemicals substances and consequently generate wastewater containing them, for example formaldehyde. This substance is widely utilized to preserve biological samples generating many liters of this residue every year. The present work proposes the use of the photo-Fenton process to treat formaldehyde wastewater using sunlight irradiation. Some aspects were investigated such as the iron source, sample and hydrogen peroxide concentration and also the use of stirred systems. The use of ferrioxalate (0.5 mmol L-1) improved the efficiency of the process in relation to the use of iron nitrate, while at least 1.0 mol L-1 H2O2 is necessary to treat the sample of the 500 mg C L-1. Under these conditions, every formaldehyde detectable was degradeted and 89% of the dissolved organic carbon was removed in two hours of exposure to sunlight. These results are satisfaction considerate for São Paulo State Environmental Agency.

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