Catalytic degredation of caffeine in aqueuos solution by cobalt-MCM41 in activating peroxymonosulfate开题报告

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1. 研究目的与意义、国内外研究现状（文献综述）

Topic:the study on methylene blue degradation by ferric oxide activated PMS

Pharmaceutical and personal care products (PPCs) have received huge attention because of the use of antibiotics, mental drugs, hormone drugs, and musk from synthetic or natural sources. The concentration of PPCs in sewage treatment plant effluent, surface/ground water, lake water, river water is in huge amounts posing huge threat to the health of the aquatic species. Therefore, it is of interest to develop efficient water treatment methods for removing PPCs from the aquatic environment. Advanced oxidation process (AOPs) are generally the best efficient methods for degrading hazardous, refractory and non-biodegradable pollutants. AOPs depends on the oxidant’s ability to degrade pollutants, and mineralize them into CO2 and water. This is the whole point of this experiment, to synthesis a suitable catalyst that can activate an oxidant capable of degrading pollutants.

Huge advances have been made in the treatment of waste water, not only in China but also in some developed countries. More sophisticated and advanced methods have been implemented and many more scientists are doing researches that will advance the current existing methods even further. The aim is to find ways to deal with environmental problems without putting a strain on the environment itself.L. Zhang, J. Niu, Y. Wang, J. Shi, Q. HuangChemosphere, 114 (2014), pp. 114-120ArticleDownload PDFView Record in ScopusI. Ross, FMC Environmental Solutions Peroxygen Talk, 2011.Google ScholarUnited States Environmental Protection Agency EPA 505-F-14-001, 2014.Google Scholar

2. 研究的基本内容和问题

The objective is to synthesis a catalyst that can activate an oxidant that can be used to degrade pollutants. In this experiment we use methylene blue as our pollutant. the key points that we need to bear in mind are that1. Some pollutants like PPCPs are resistant to natural degradation, so we need to overcome that.2. During the degradation process there may be some small traces of secondary pollutants.3. We need to deal with any leaching of the involved materials that may appear.

3. 研究的方法与方案

The research is divided into 2 phases.1. catalyst synthesis:600ml of water is added into a large beaker, then the following ingredients are added: 45.6g of Polyvinylpyrolidane (PVP), 0.1 mol/L of HCL(used to adjust the Ph), 1.32g of potassium ferocyonite trihydrate. The mixture was stirred for 30 minutes and it was then heated for 24 hours on constant temperature of 80°C.The mixture was then equally poured into 6 small tubes which were then centrifuged for 45 minutes at 11100rmp. Finally the catalyst was produced.2. Degradation process:This is where the oxidant’s degradability against pollutants is tested.Effect of 2 Fe_2O_3 Dosage on Degradation Rate of Methylene BlueUnder the conditions of25℃, initial Ph6.0, PMS0.2mm, methylene blue 10mg/L, Change the dosage of catalyst ( 0.05, 0.1, 0.15, 0.2g/ L), study its effect on the degradation rate of methylene blue and determine the best dosage of catalyst.Effect of 3 PMS Dosage on Degradation Rate of Methylene BlueAt25℃, initial Ph6.0, the catalyst dosage 0.1g/L, methylene blue 10mg/L, The effects of PMS concentration ( 0.1, 0.15, 0.2 and 0.25mM) on the degradation rate of methylene blue were studied and the optimal dosage of oxidant was determined.Effect of initial pH on the degradation rate of methylene blueAt25℃, PMS 0.2mM, methylene blue 10mg/L, catalyst addition 0.1g/L, Change the initial pH ( 4.0, 6.0, 7.5, 9.0), study its effect on the degradation rate of methylene blue and determine the best initial pH.Effect of temperature on degradation rate of methylene blueAt initial pH6.0, the catalyst dosage was 0.1g/L, 10mg/L methylene blue, and PMS 0.2Mm, The effects of reaction temperature ( 20, 30, 40, 50) on the degradation rate of methylene blue were studied. The effect of reaction temperature on the degradation rate of methylene blue was also studied, and the optimum temperature was determined.Effect of inorganic salt ions on the degradation rate of methylene blueAt initial Ph6.0, 0.1g/L catalyst was added, Methylene blue 10mg/L, PMS 0.2mM, temperature25℃, adding a certain amount of sodium chloride to the solution, Sodium dihydrogen phosphate, sodium bicarbonate, concentration gradients were 5, 10, 20, 200mM. The effects of these three common inorganic salts on the degradation rate of methylene blue were studied.

4. 研究创新点

The experiment that I am doing falls under the advanced oxidation processes (AOPs), and there are many methods/innovation that are classified under the broad definition of AOPs.Advanced oxidation generally uses strong oxidizing agents like hydrogen peroxide (H2O2) or ozone (O3), catalysts (iron ions, electrodes, metal oxides) and irradiation (UV light, solar light, ultrasounds) separately or in combination under mild conditions (low temperature and pressure).AOP mechanism:1. Formation of strong oxidants (e.g. hydroxyl radicals).2. Reaction of these oxidants with organic compounds in the water (KOMMINENI et al. 2008) producing biodegradable intermediates.3. Reaction of biodegradable intermediates with oxidants referred to as mineralization (i.e. production of water, carbon dioxide and inorganic salts).This process can be applied in many different ways, like treating waste water, air pollution and land pollution, and it will allow us to innovate even more efficient ways that can be used to treat pollution, it opens doors for other scientists to add ideas on the already existing methods.Examples of AOP:DARK AOP Light driven AOPOzone O3 photolysisFenton(Fe2 H2O2) Photocatalysis (light catalysis)Electrolysis (electrodes current) Photo-fenton (solar light FentonSonolysis(ultrasound)

5. 研究计划与进展

from 11-March-201 to 25-April-2019 I will be doing the experiment in the laboratory of资源与环境科学学院 room A403.At the beginning of May the draft of graduation thesis(must be in Word version) will be examined by the teacher(丁大虎 老师). Mid-May the graduation thesis must be in a final draft and submitted to the teacher review.PPT preparation at the end of May and presentation.