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Summary of doctoral thesis: Study to determine the content of some chlorbenzen compounds from unintentional emission sources in industrial zones in Thai Nguyen province

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Research objectives of the thesis: Study the process of simultaneous determination and evaluation of the method of analyzing 7 chlorobenzene, including 1,2- 4 dichlorobenzene (1,2-DCB); 1,3-dichlorobenzene (1,3-DCB); 1,2,4- trichlorobenzene (1,2,4-TCB); 1,2,3,4-tetrachlorbenzene (1,2,3,4- TeCB), 1,2,4,5-tetraclobenzene (1,2,4,5-TeCB); pentaclobenzene (PeCB) and hexaclobenzene (HCB) in trace and superficial content in flue gas samples and industrial waste (fly ash, bottom ash, input materials).

MINISTRY OF EDUCATION AND TRAINING VIETNAM ACADEMY OF SCIENCE AND TECHNOLOGY GRADUATE UNIVERSITY SCIENCE AND TECHNOLOGY - *** - STUDY TO DETERMINE THE CONTENT OF SOME CHLORBENZEN COMPOUNDS FROM UNINTENTIONAL EMISSION SOURCES IN INDUSTRIAL ZONES IN THAI NGUYEN PROVINCE Major: Analyticalchemistry Code: 9.44.01.18 SUMMARY OF DOCTORAL THESIS Ha Noi, 2019 This thesis is completed at: Vietnam Academy of Science and Technology Scientific instructors: Assoc Dr TU BINH MINH Assoc Dr NGUYEN THI HUE Thesis reviewer 1: Prof Dr Thesis reviewer 2: Assoc Dr Thesis reviewer 3: Assoc Dr The thesis will be presented to the scientific council at the Vietnam Academy of Science and Technology at … h, date … , month … , year 2019 INTRODUCTION The urgency of the thesis Research on the pollution of persistent organic compounds (POPs) has been receiving the attention of many scientists all around the world The assessment of pollution levels and emissions of dioxinlike chlorobenzene compounds such as hexaclobenzene (HCB), Pentaclobenzene (PeCB), tetrachlorene (TeCB), triclobenzene (TCB), diclobenzene (DCB) is the scientific basis for countries Participating in signing the Stockholm Convention to implement the plans for management, disposal and environmental pollution treatment by POPs well In Vietnam, the focus is mainly on studying U-POPs such as dioxin, furans and PCBs in soil, sediment, organisms and human Disclosures related to unintentional emissions of chlorbenzen compounds into the environment from industrial manufacture and waste disposal in Vietnam are limited From above problems, it is necessary to research into the overall sources of emissions and the level of environmental pollution caused by the sources of industrial waste of chlorbenzenes, optimizing the efficiency of the process analysis in accordance with conditions in Vietnam This is a topical issue in current conditions when health and environment in Vietnam are at an alarming level Therefore, I decided to choose the topic "Study to determine the content of some chlorbenzen compounds from unintentional emission sources in industrial zones in Thai Nguyen province", contributing to the protection and sustainable development of ecological environment in Thai Nguyen province Research objectives of the thesis - Study the process of simultaneous determination and evaluation of the method of analyzing chlorobenzene, including 1,2- dichlorobenzene (1,2-DCB); 1,3-dichlorobenzene (1,3-DCB); 1,2,4trichlorobenzene (1,2,4-TCB); 1,2,3,4-tetrachlorbenzene (1,2,3,4TeCB), 1,2,4,5-tetraclobenzene (1,2,4,5-TeCB); pentaclobenzene (PeCB) and hexaclobenzene (HCB) in trace and superficial content in flue gas samples and industrial waste (fly ash, bottom ash, input materials) - Adopting an optimal procedure to simultaneously identify chlorobenzene in industrial samples including waste gas, ash, materials of some industrial fields in industrial zones in Thai Nguyen province - Preliminary assessment of the level and emission characteristics of chlorobenzene from the thermal process of a number of industrial fields including waste incinerators, metallurgy, brick production and cement production The main research contents of the thesis - Study the process of simultaneous determination and evaluation of the method of analyzing chlorobenzene + Survey and select optimal conditions to analyse chlorbenzen compounds on gas chromatography equipment using electronic resonance detector (GC-ECD) and mass spectrometry (GCMS) + Investigate optimization of processing samples including extraction, cleaning and enrichment + Verification of analytical methods: determination of linear range, calibration curve, detection limit and quantitative limit, recovery coefficient and repeatability of the method - Apply the optimal procedure to simultaneously identify chlorbenzenes in industrial samples + Analysis of the content of chlorbenzenes in gas samples and solid samples taken from factories in Thai Nguyen province and some northern provinces on GC-ECD equipment and confirm the presence of above chlorinated benzene compounds GC-MS + Evaluation of homogeneous characteristics is the ratio of the content of each substance to the total content of chlorobenzene, in the types of industrial waste gases and solid waste samples + Evaluation of emission factors is to find out annual emissions and the risk of chlorobenzene on humans from a number of industries in Thai Nguyen province New contributions of the thesis Optimized conditions to simultaneously identify clobezen targets, in industrial samples (waste gas samples and waste solid samples (Fly ash, bottom ash) in trace amounts and super stains using GC-ECD and GC-MS Successfully developed the process of analyzing chlorbenzen compounds in trace amounts and super stains The first step was to identify and determine the emission level through the emission factor and the annual emission of chlorbenzenes from industrial solid waste samples in Thai Nguyen province This is the first published study in Vietnam on unintentional emission levels of chlorbenzenes in some industries Thereby contributing to the control of emissions to limit and completely eliminate hazardous POPs in the environment, meeting the requirements of the Stockholm Convention, towards sustainable development in Vietnam CHAPTER 1: OVERVIEW OF RESEARCH PROBLEMS 1.1 OVERVIEW OF THE RESEARCH SUBJECT 1.1.1 Overview of Chlorobenzens Derivatives of chlorbenzenes C6H (6-x) Clx form a stable and colorless group with a pleasant odor Chlorine can be substituted for six hydrogen atoms on benzene rings to be able to form twelve different chlorinate compounds including: Monoclobenzene (MCB); ortho-diclobenzene (1,2-DCB); meta-diclobenzene (1,3-DCB), paradiclobenzene (1,4-DCB); 1,2,3-triclobenzene, 1,2,4-triclobenzene; 1,3,5-triclobenzene; 1,2,3,4-tetraclobenzene; 1,3,4,5-tetraclobenzene; 1,2,4,5-tetraclobenzene; Pentaclobenzene; Hexaclobenzene The physical and chemical properties of clobenzene (CBz) compounds when they are released into the environment, are likely to evaporate into the atmosphere The atmospheric CBz will be decomposed primarily through reactions with hydroxyl radicals to produce nitroclobenzene, clophenol, and fatty dicarbonyl products, which continue to be removed by photochemistry or reaction with hydroxyl radicals CBz compounds released into water will accumulate in suspended solids and sediments (especially rich organic sediments) All CBz are easily absorbed by humans and animals through the digestive and respiratory pathways.The absorption is affected by the position and number of chlorine in chlorobenzene congeners After absorption, chlorbenzenes quickly distribute to organs, accumulate mainly in adipose tissue and can remain there for a long time, in small amounts in the liver and other organs 1.1.2 the formation of chlorbenzen compound from some industrial activities An incomplete destruction of burned materials in which CBz is available CBz Formed by the metabolism of compounds is precursor or formed in low temperature areas from carbon particles and chlorine compounds - synthesized denovo However, the CBz emission content during combustion depends very much on the combusting conditions and the presence or absence of catalytic materials CBz can also be formed due to the chlorination process of HCB (Figure 1.1) in the presence of catalysts such as Cu, CuO, High / a-Fe2O3 metal .) to create copper lower chlorine CBs 1.2 DOMESTIC AND OVERSEAS STUDY SITUATION 1.2.1 Studies in the world In recent years, a number of studies have also focused on unintentional POPs emissions from the production of non-ferrous metals and ferrous metals, iron ore production of iron and steel, coke production and other secondary color metallurgy process A research in China in the industry of zinc and lead metals production in 2007 showed that the average emission factor of PCDD / Fs in gas samples for lead and zinc manufacturing industry is 98.2 and 0.35, respectively ng TEQ / (Nm3); in fly ash samples is 5.64 ng TEQ / g with zinc industry; 0.05 ng TEQ / g in lead manufacturing industry Emission factors of gas samples for PCBs from zinc and lead production are respectively 2,786 and 0,002 ng TEQ / Nm3.The formation and reduction of emissions of clobenzene, polychlorinated dibenzo-pdioxin and dibenzofurans polychlorinated (PCDD / Fs) have been studied in a typical dry cement kiln in China Emissions of PCDD / F and CBz in emissions are 0.16 ng I-TEQ Nm-3 and 26 µg / Nm3 respectively The concentration of 1,2-DCB ranges from 100 - 9424 ng / Nm3; 1.3 and 1.4 –DCBz are 223 - 6409 ng / Nm3 1,3,5 / 1,2,4 / 1,2,3- TCB in the range of 35 - 3542 ng / Nm3 (of which 1.2, accounts for the largest amount); 1,2,3,5-TeCB & 1,2,4,5-TeCB range between - 491 ng / Nm3, while isomer 1,2,3,4-TeCB is - 562 ng / Nm3 ; Concentrations PeCB and HCB range from to 335 ng / Nm3 and to 128 ng / Nm3 respectively 1.2.2 Domestic studies in Vietnam Studies on POPs compounds such as dioxin / furan, DDT, PCBs in Vietnam have been of interest since the end of the 20th century because of their toxicity and changes in awareness in environmental protection of managers as well as scientists However, in Vietnam, the focus is only on studying POPs in environmental objects of soil, sediment, organisms and people to overcome the consequences of chemical toxins / dioxin No claims have been made regarding the assessment of the emissions of chlorbenzen compounds (DCB, TCB, TeCB, PeCB, HCB) unintentionally emissions in many industrial production and recycling industries So the assessment and comparison of pollution levels and emission sources for this group of substances face many difficulties CHAPTER 2: EXPERIMENT AND RESEARCH METHOD 2.1 SCOPE AND SUBJECTS OF RESEARCH The research object of the thesis is chlorbenzen targets of isomers, including dichlorobenzene (1,2; 1,3 - DCB); trichlorobenzene (1,2,4TCB); tetraclobenzene (1,2,3,4; 1,2,4,5-TeCB); Pentaclobenzene (PeCB) and hexaclobezen (HCB) * Industrial factories and incinerators in Thai Nguyen province are listed in table 2.1 * Industrial production plants and incinerators in Northern provinces of Vietnam collected for comparison with samples collected from Thai Nguyen Table Information about actual samples orde r Sample factory name Date of samplin g Factor y sign Type of productio n Capacit y (ton / h) Emissio n rate (Nm3 / h) Averag e capacit y / year THÁI NGUYÊN Viet Trung black metallurgy factory Metallurgic al company 03/2014 NMLK iron and steel 6,0 31000 8040 06/2014 NMLK Zinc oxide 1,0 14700 7000 8 10 11 12 Duc Thinh Mechanical Company Thai Nguyen Black Metallurgy Joint Stock Company Nam Son Black Metallurgic al Plant Mechanical Factory Z115 Ministry of Defense Thai Nguyen Thai Son tunnel brick factory Khe Mo tunnel brick factory Quan Trieu Cement Factory Phuc loi Trade and Service Cooperativ e Dong Hy General Hospital Incinerator for domestic waste - DaPhu Luong town Household waste 12/2017 NMLK Cast Iron 2,5 - 2496 03/2017 NMLK Cast Iron 5,8 - 8040 12/2017 NMLK Steel rolling 0,04 - 8040 03/2014 NMVL Brick 5,8 16500 6530 03/2017 NMVL brick 5,0 - 8040 06/2014 NMVL Cement 40 - 7920 06/2014 LDCN Industrial waste 0.25 20000 2640 03/2014 LDYT Medical waste 0.2 - 1536 03/2017 LDSH Domestic waste 0,45 - 2900 03/2017 LDSH Domestic waste 0,7 - 2900 13 14 incinerator - Song Cau town Waste incinerator Trai CauTan Cuong waste incinerator waste incinerator Tan Cuong town 03/2017 LDSH Domestic waste 0,45 - 2900 03/2017 LDSH Domestic waste 0,7 - 2900 2.2 RESEARCH METHODS 2.2.1 Objectives of the study 2.2.2 research content 2.2.3 Methods of document review 2.2.4 Survey method 2.2.5 Experimental method 2.2.5.1 Sampling, shipping and preservation methods 2.2.5.2 Sampling and actual sample information 2.2.5.3 Method of CBz analysis on GC-ECD equipment 2.2.5.4 Study the sample processing process and confirm the use value of the method 2.2.5.5 Analysis of real samples 2.2.5.6 Evaluation of emission levels and assessment of the risk of chlorbenzen compounds 10 CHAPTER 3: RESULTS AND DISCUSSION 3.1 SURVEY THE OPTIMIZED CONDITIONS FOR ANALYSIS OF CBZ TIMES ON GAS ACCESSORIES 3.1.1 Investigate optimal conditions with CBz standard solution on GC-ECD equipment 3.1.1.1 Column temperature program According to the results, it was found that the increase of high temperature from 120oC – 150oC was not suitable, so the thesis selected the temperature of 70o C as the initial temperature then gradually increased the temperature to 120oC in minutes, the separation of substances with more reasonable retention time CBz results show that at a low heating rate of ° C / long analysis time (more than 30 minutes) causes time to analyze as well as other factors High heating speed of 20° C / causes peaks to be eluted quickly, thus resulting in peak duplication At a heating speed of 10°C / min, it’s good for peak separation and reasonable analysis time (about 20 minutes) Therefore, choosing a heating speed of 10° C / for further studies After investigating the optimal conditions when analyzing CBz with GC-ECD, the parameters are listed in Table 3.1 Table 3.1 Excellent parameters when analyzing CBz on GC-ECD 2010 device Pump port temperature 220 ° C Air flow mode Pressure Column head pressure 100 kPa Volumetric suction µl sample Pump mode Divide the line Line split rate 1:10 Sample pumping Pressure program rate Flow through ml / minute column Separation column SPB-608 (30 m × 0.25 mm ì 0.25 àm) Column oven temperature program 70 oC Heating speed 10° C / min; hold 70 oC to 120oC minutes 12 120 oC to 280oC Heating speed 10° C / min; hold for Total analysis timephân minutes 18minutes tích Detector Temperature 300 °C Gas carries Nitrogen 3.1.1.2 Sample pump conditions Results of analysis on GC-ECD showed that when using nonsplit mode, the peak has a special tail-pulling phenomenon at peak and 2, which affects the process of determining the area of peak used for quantification The thesis chooses split-line mode to analyze CBz on GC-ECD equipment At low current conditions of 1: 5, peaks tend to move toward the solvent peak 1: 20 high current split conditions for low signal PeCB, HCB signal, increase the influence of baseline during analysis Therefore, the thesis uses the ratio of 1:10 for the peaks of the CBz signals and is used in the next survey conditions The result of retention time of CBz is shown in Table 3.2 Table 3.2 Retention time of CBz standard solutions on GCECD equipment Number Name of substance 1.3 Diclobenzen 1.2 Diclobenzen 1.2.4 Triclobenzen 1.2.4.5 Tetraclobenzen 1.2.3.4 Tetraclobenzen Pentaclobenzen Hexaclobenzen CB 209 Pentanitroclobenzen Retention time (minute) 4.667 5.310 7.812 10.707 11.974 14.016 16.729 17.545 17.885 3.1.2 Results of evaluation of stability of CBz analytical signal on GC-ECD device 3.1.2.1 Stability of analytical signals Calculated results of research CBz for repeated injections of standard solution at low concentration C1 and high concentration C2 have RSD values varying from 1.27% to 15.0% ( HCB> DCB> TeCB> PeCB Comparison of daily intake of 1,3-DCB, 1,2,4-TCB, 1,2,4,5-TeCB, 1,2,3,4-TeCB, PeCB and HCB, and steam absorption Daily allowance allowed (TDI), These findings suggest the need to monitor continuous emissions and assess human exposure to chlorine compounds not only continuously for PeCB and HCB but also for reducing chlorinated congeners This is also the first data on CBz emission factors and emissions from a number of industrial types such as waste incineration and steel making This information may be useful for controlling unintentional persistent organic pollutants (UPOP) in Vietnam CONCLUSIONS Successfully developed a process of simultaneous analysis of co-chlorinated benzene (1,2-dichlorobenzene, 1,3-dichlorobenzene; 1,2,4-trichlorobenzene; 1,2,4,5-tetraclobenzene; , 2,3,4tetrachlorobenzene, pentacarbonbenzene and hexacarbonbenzene) in industrial waste and solid waste samples, including sample and qualitative processing, quantified on two GC-ECD and GC-MS devices Results showed that detection limits of chlorbenzenes ranged from 0.05 to 0.17 ng / g; Quantitative limits range from 0.16 to 0.391 ng / g Recovery is in the range of 79.7 - 113% (with standard deviation practice of iron, steel, metal, zinc oxide> tunnel brick> cement The concentrations of chlorobenzene of these industries ranged from 2.0 to 69.8 ng / Nm3 for flue gas samples and 2.69 to 70.1 ng / g for waste solid samples The homogeneous characteristic of chlorbenzenes exhibits a clear variation in various industries, proving that the formation mechanism is not intentionally complicated at these industrial facilities Initial assessment of unintentional levels of chlorobenzene through calculation of emission factors and annual emissions of these substances in waste incinerators, metallurgy, tunnel bricks, cement Emission factors of chlorbenzen substances oscillating in flue gas samples are about 11.6 - 889 µg / ton with annual emissions from 441000 - 17391000 µg / year; Emission factors in solid samples range from 0.002 to 23.3 µg / ton with annual emissions of - 95600 µg / year LIST OF PUBLISHED WORKS Nguyen Thi Hue, Nguyen Thi Thu Thuy, Nguyen Hoang Tung, Polychlorinated benzenes and polychlorinated biphenyls in ash and soil from several industrial areas in the Northern Vietnam: residue concentrations, profiles and risk assessment, Eviron Geochem Health, 2016, 38: 399-411 Nguyễn Thị Thu Thúy, Nguyễn Thị Huệ, Nghiêm Xn Trường, Hồng Quốc Anh, Từ Bình Minh, Đánh giá mức độ phát thải chất ô nhiễm hữu khó phân hủy phát sinh khơng chủ định từ số hoạt động công nghiệp miền Bắc Việt Nam, Tạp chí Khoa học Đại học quốc gia Hà nội - Khoa học công nghệ, 2016, 32 (3), 35 - 40 Nguyễn Thị Thu Thúy, Nguyễn Thị Huệ, Từ Bình Minh, Khảo sát xây dựng quy trình phân tích lượng vết chất Pentaclo benzen hexaclo benzen mẫu tro bụi số ngành cơng 25 nghiệp, Tạp chí Khoa học Đại học quốc gia Hà nội - Khoa học công nghệ, 2016, 32 (3), 262 - 267 Nguyễn Thị Thu Thúy, Nguyễn Thị Huệ, Nguyễn Hoàng Tùng, Từ Bình Minh, Mức độ nhiễm, phát thải đánh giá rủi ro chất Polyclo benzen Polyclo biphenyl mẫu tro bay đất từ khu công nghiệp miền Bắc Việt Nam, Tạp chí Khoa học Đại học quốc gia Hà nội - Khoa học công nghệ, 2016, 32 (3), 12 18 Nguyễn Thị Thu Thúy, Vũ Văn Tú, Nguyễn Thị Huệ, Trần Mạnh Trí, Từ Bình Minh, Mức độ nhiễm phát thải hợp chất clobenzen phát sinh không chủ định từ số ngành công nghiệp miền bắc Việt Nam, Tạp chí Hóa học, 2018, 56 (3 E12), 135 – 138 Hue Thi Nguyen, Thu Thuy Thi Nguyen, Tung Hoang Nguyen, Anh Quoc Hoang, Long Hai Pham, Tu Binh Minh, Levels, profiles and emission characteristics of chlorobenzenes in ash samples from some industrial thermal facilities in northern Vietnam, Environmental Science and Pollution Research (ESPR),DOI: 10.1007/s11356-0183591-9, ESPR-D-18-06017.2 Hue Nguyen Thi, Thuy Nguyen Thi Thu, Long Pham Hai, Hai Nguyen Thanh, Hai Chu Viet, Hue Chu Thi, Truong Nghiem Xuan, Nguyen Hoang Tung, Emission of Unintentionally Produced Persistent Organic Pollutants from Some Industrial Processes in Northern, Bulletin of Environmental Contamination and Toxicology, online 13.12.2018, doi.org/10.1007/s00128-018-2519-x Nguyễn Thị Thu Thúy, Nguyễn Thị Huệ, Chu Thị Huệ, Đặng Văn Đồn, Hồng Quốc Anh, Trần Mạnh Trí, Từ Bình Minh, Xác định đồng thời lượng vết chất chlorobenzen mẫu tro bụi số khu cơng nghiệp miền Bắc Việt Nam, Tạp chí Hóa học, 2018, 56 (6 E1), 185-189 26 ... alarming level Therefore, I decided to choose the topic "Study to determine the content of some chlorbenzen compounds from unintentional emission sources in industrial zones in Thai Nguyen province" ,... hexaclobezen (HCB) * Industrial factories and incinerators in Thai Nguyen province are listed in table 2.1 * Industrial production plants and incinerators in Northern provinces of Vietnam collected... identify chlorbenzenes in industrial samples + Analysis of the content of chlorbenzenes in gas samples and solid samples taken from factories in Thai Nguyen province and some northern provinces

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