TREATMENT OF SPENT CAUSTIC LIQUOR BY CATALYTIC WET OXIDATION

Catalytic activity of CuO-supported catalyst in phenol oxidation, and the influence of reaction conditions, viz. temperature (125-170 °C), oxygen partial pressure (1-7 MPa) and liquid feed (30-760 ml h-1), in the continuous operation using 17.9 mm i.d. trickle-bed reactor is presented. The hydrodynamic impact on the three-phase trickle-bed reactor performance in an environmental application of catalytic wet oxidation was also investigated. The results of trickle-bed operation were strongly influenced by wetting efficiency. An insufficient catalyst wetting can be to compensated by filling the catalyst bed voids by fine glass spheres. In the case of the gas transfer limited reaction, a better wetting of the catalyst can lead to worse reactor performance due to lower reaction rates.

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Selective Organic Removal from the Alumina Industrial Liquor: Wet Oxidation and Catalytic Wet Oxidation of Disodium Malonate

Industrial & Engineering Chemistry Research ◽

10.1021/ie010364f ◽

2002 ◽

Vol 41 (5) ◽

pp. 1166-1170 ◽

Cited By ~ 6

Author(s):

Sharon Eyer ◽

Suresh Bhargava ◽

James Tardio ◽

Deepak B. Akolekar

Keyword(s):

Wet Oxidation ◽

Catalytic Wet Oxidation ◽

Organic Removal

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The use of catalyst to enhance the wet oxidation process

Water Science & Technology ◽

10.2166/wst.2007.405 ◽

2007 ◽

Vol 55 (12) ◽

pp. 189-193 ◽

Cited By ~ 4

Author(s):

C. Maugans ◽

B. Kumfer

Keyword(s):

Acetic Acid ◽

Catalytic Activity ◽

Acrylic Acid ◽

Oxidation Process ◽

Wet Oxidation ◽

Test Results ◽

Pure Compound ◽

Spent Caustic

Wet oxidation tests were performed on two pure compound streams: acetic acid and ammonia; and on two wastewater streams: acrylic acid wastewater and sulphide laden spent caustic. Test results showed that Mn/Ce and Pt/TiO2 were effective catalysts that greatly enhanced acetic acid, ammonia and acrylic acid wastewater destruction. However, the Mn/Ce catalyst performance appears to be inhibited by concentrated salts dissolved in solution. This could limit the applicability of this catalyst for the treatment of brackish wastewaters. Zr, Ce and Ce nanoparticles were also shown to exhibit some catalytic activity, however not to the extent of the Mn/Ce and the Pt/TiO2.

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Catalytic wet oxidation of high concentration pharmaceutical wastewater with Fe3+ as catalyst

Water Science & Technology ◽

10.2166/wst.2018.216 ◽

2018 ◽

Vol 2017 (3) ◽

pp. 661-666

Author(s):

Xu Zeng ◽

Jun Liu ◽

Jianfu Zhao

Keyword(s):

Oxygen Pressure ◽

Batch Reactor ◽

Oxygen Demand ◽

Kinetic Studies ◽

Cod Removal ◽

Wet Oxidation ◽

Catalytic Wet Oxidation ◽

Pharmaceutical Wastewater ◽

High Concentration ◽

Temperature Time

Abstract Catalytic wet oxidation of high concentration pharmaceutical wastewater with Fe3+ as catalyst was carried out in a batch reactor. Results showed that the degradation of pharmaceutical wastewater was enhanced significantly by Fe3+. The effects of reaction parameters, such as the catalyst dose, reaction temperature, time, and initial oxygen pressure, were discussed. The chemical oxygen demand (COD) removal increased with the increases of catalyst dose, temperature, time and oxygen supply. With the initial COD 34,000–35,000 mg/L, approximately 70% COD removal can be achieved under the conditions of catalyst 1.0 g and oxygen pressure 1.0 MPa at 250 °C after 60 min. The results of kinetic studies showed that two reaction steps existed in this oxidation process, which followed an apparent first-order rate law. This process provides an effective approach for the pretreatment of high concentration pharmaceutical wastewater.

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