1. Full name:     Nguyen Thi Kim Giang                   2. Sex: female

3. Date of birth: 10-10-1984                                    4. Place of birth: Hung Yen province

5. Admission decision number: Decision No. 4860 / QD-DHKHTN dated November 24, 2014 of the Rector of University of Natural Sciences - Hanoi National University.

6. Changes in academic process: No

7. Official thesis title: Study on synthesis of oxygen-containing activated catalyst system (H2O2 and acetic acid) to treat some pigments in textile wastewater

8. Major:                       Environmental Chemistry                                  Code: 9440112.05

10. Supervisors:  Assoc. Prof. Cao The Ha

11. Summary of the new findings of the thesis:

The research purpose of the thesis is to evaluate the industrial dyestuff decolorization activity of peracetic acid, as a premise for the development of color treatment technology in textile wastewater and biodegradable organic substances in waste water by agents containing peroxy in Vietnam. The main results are obtained as follows:

For the formation and decomposition of PAA:

1. The formed PAA reaches the maximum equilibrium concentration of 2,61 M when the volume ratio CH3COOH (100%): H2O2 (30%) = 1.5: 1. The reaction is catalyzed by an acid medium (when H+ is not added, the reaction takes 2 days to reach equilibrium; when H+ is added to a concentration of 0,74 M, equilibrium is reached within 1 hour).

2. Kinetic model of PAA formation is determined with the reaction order of H2O2 and the catalyst is equal to 1.

3. From the results of determining the concentration of substances at the time of equilibrium, the equilibrium constant (K) of the reaction is determined by 4,04 (mean value).

4. PAA decomposes itself in solution upon dilution. Decomposition rapidly with increasing pH value.

As for the color removal capacity of PAA:

1. Among the 4 metal ions examined catalytic activity (Cu2+, Mn2+, Fe3+, Co2+), Co2+ gave the highest efficiency.

2. The color reduction activity of PAA is influenced by the pH value of the reaction solution. As pH increases, the rate of decolorization increases. This phenomenon can be explained by the fact that a high pH environment favors free radical formation.

3. The reaction kinetic model has been proposed with the reactance order of the dye 1.

4. UV rays help to increase the reactivity of PAA by increasing the ability to create free radicals.

The newness of the thesis obtained includes:

1. Quantify the formation of PAA under H+ catalytic conditions. This is useful information for local PAA modulation for use.

2. Build a dynamic model to form PAA and determine the reaction order of H2O2 is 1.

3. Finding Co2+ is an effective catalyst for the color reduction process by PAA, and at the same time find out a rule that affects the pH of the reaction rate.

12. Practical applicability, if any: Wastewater treatment containing organic and sustainable (dyes, minerals, pesticides, ...).

13. Further research directions:

Study on treating textile and dyeing wastewater with PAA+ Co2+ pilot scale for pre-feasibility study (determine technical parameters, operating costs) for wastewater treatment.

14. Published works related to the thesis:

[1] Nguyen Thi Kim Giang, Tran Thi Hai Yen, Nguyen Huu Tho, Nguyen Thi Hien, Cao The Ha, Le Van Chieu, Vu Ngoc Duy, “Kinetics of CH3COOH formation from CH3COOH + H2O2 reaction in the presence of ion H+”, VNU Science Journal: Natural Science and Technology, Vol. 34, No. 2 (2018) 91-95.

[2] Nguyen Thi Kim Giang, Cao The Ha, Vu Ngoc Duy, “Catalytic effect of Cobalt (II) ion in the reaction between Peracetic Acid and Reactive Blue 19”, Journal of Chemistry, Volume 56, Issue 3E12, (2018) 105-109.

[3] Nguyen Thi Kim Giang, Cao The Ha, Vu Ngoc Duy, “The Kinetic of Decolorizing Reactive Orange 122 (RO122) by Peracetic Acid in the Presence of Metal Ions and UV Light”, VNU Journal of Science: Natural Sciences and Technology, Vol. 35, No. 3, (2019) 1-6.