Method development for chemolysis of waste tyres and characterization of the components
- Authors: Tsipa, Phuti Cedric
- Date: 2018
- Subjects: Composite materials , Rubber Chemistry, Organic
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/36694 , vital:34044
- Description: Chemolysis method for degradation and extraction of waste tyres for production of oil was developed. This method consist of three different solvent systems; firstly, the selective solvent system capable of extracting the process oil used in the production of tyres. This solvent system follows a phase transfer catalysis reaction, which is a reaction with a solvent consisting of two phases. Second system is a Destructive solvent system, which is capable of breaking down the polymer chains within the rubber matrix. It follows phase transfer catalysis reaction. Lastly, the collecting/wash solvent system, which is capable of collecting the remaining extracts in the residual crumb. Three products where obtained from this method: Liquid (oil), Gas and Solid (char), with the oil plus char being the focus of this study. Characterizations were carried out to obtain the quality of the oil recovered. Various analytical techniques were used to achieve the aims and objectives of this study, this involved Fourier Transform Infra-red spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) spectroscopy, High-resolution Thermogravimetric analysis (Hi-resTM TGA), Gas Chromatography coupled to Mass spectroscopy (GC-MS) and Simulated Distillation D86 (SIMDIST D86). Hydrocarbon compounds and market value acids where identified with reference to standards ran on the GC-MS. Market value acids were quantified to obtain the exact amount present in the extracted oil, the amounts for dodecanoic acid, hexadecanoic acid, heptadecanoic acid and octadecanoic acid were 0.73%, 5.1%, 0.49% and 9.98% respectively. Approximately 15% of this market value acid are present in the extracted oil. Internal GC-MS library and Retention Index (RI) methods with the help of NIST library were also used for compounds identification. A total of 53 compounds were successfully identified. SIMDIST D86 analysis showed that the petroleum fractions present in the total extracted oil were Heavy naphtha 0.73%, Kerosene 3.23%, Distillate fuel oil 6.27%, Light vacuum gas oil 57.93% and Heavy vacuum gas oil 31.83%. Hi-resTM TGA was used to characterize the char recovered for thermal properties. Chemolysis char showed relatively similar thermal stability compared to commercial N115 carbon black. The chemolysis method of oil extraction from waste tyres reported in this thesis shows promise in terms of both the routine of execution, quantification of market value constituents of the oil and chemical details of both the tyre derived oil and char.
- Full Text:
- Date Issued: 2018
- Authors: Tsipa, Phuti Cedric
- Date: 2018
- Subjects: Composite materials , Rubber Chemistry, Organic
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/36694 , vital:34044
- Description: Chemolysis method for degradation and extraction of waste tyres for production of oil was developed. This method consist of three different solvent systems; firstly, the selective solvent system capable of extracting the process oil used in the production of tyres. This solvent system follows a phase transfer catalysis reaction, which is a reaction with a solvent consisting of two phases. Second system is a Destructive solvent system, which is capable of breaking down the polymer chains within the rubber matrix. It follows phase transfer catalysis reaction. Lastly, the collecting/wash solvent system, which is capable of collecting the remaining extracts in the residual crumb. Three products where obtained from this method: Liquid (oil), Gas and Solid (char), with the oil plus char being the focus of this study. Characterizations were carried out to obtain the quality of the oil recovered. Various analytical techniques were used to achieve the aims and objectives of this study, this involved Fourier Transform Infra-red spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) spectroscopy, High-resolution Thermogravimetric analysis (Hi-resTM TGA), Gas Chromatography coupled to Mass spectroscopy (GC-MS) and Simulated Distillation D86 (SIMDIST D86). Hydrocarbon compounds and market value acids where identified with reference to standards ran on the GC-MS. Market value acids were quantified to obtain the exact amount present in the extracted oil, the amounts for dodecanoic acid, hexadecanoic acid, heptadecanoic acid and octadecanoic acid were 0.73%, 5.1%, 0.49% and 9.98% respectively. Approximately 15% of this market value acid are present in the extracted oil. Internal GC-MS library and Retention Index (RI) methods with the help of NIST library were also used for compounds identification. A total of 53 compounds were successfully identified. SIMDIST D86 analysis showed that the petroleum fractions present in the total extracted oil were Heavy naphtha 0.73%, Kerosene 3.23%, Distillate fuel oil 6.27%, Light vacuum gas oil 57.93% and Heavy vacuum gas oil 31.83%. Hi-resTM TGA was used to characterize the char recovered for thermal properties. Chemolysis char showed relatively similar thermal stability compared to commercial N115 carbon black. The chemolysis method of oil extraction from waste tyres reported in this thesis shows promise in terms of both the routine of execution, quantification of market value constituents of the oil and chemical details of both the tyre derived oil and char.
- Full Text:
- Date Issued: 2018
The determinants of tender opportunities in consulting engineering firms in the Eastern Cape
- Authors: Viljoen, Dirk Johannes
- Date: 2017
- Subjects: Tender offers (Securities) -- South Africa -- Eastern Cape Consulting engineers -- South Africa -- Eastern Cape Engineering firms -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/14102 , vital:27426
- Description: Management of an engineering consultancy unit in the Eastern Cape Province is concerned about the costs incurred by project managers and specialist engineers pursuing tender opportunities that are not feasible. Annual losses in this unit due to unsuccessful tenders amounts to R2,5 million annually, which equates to about 12% of the revenue generated by the unit. The aim of the research study is to assist the consulting engineering firm by investigating and identifying the key determinants for making the decision of whether to bid on a particular tender opportunity. The study includes an assessment of relevant literature, academia and text to investigate key factors that could influence the decision to bid on tenders from which research questions and appropriate theories were drawn. Based on the research questions and theories that emanated from the literature, the study also includes the assessment of primary data through the administration of a structured questionnaire. The questionnaire is empirically analysed within the positivistic research paradigm through the use of descriptive and inferential statistics. Conclusions are drawn and recommendations are made based on the findings of the administered questionnaire.
- Full Text:
- Date Issued: 2017
- Authors: Viljoen, Dirk Johannes
- Date: 2017
- Subjects: Tender offers (Securities) -- South Africa -- Eastern Cape Consulting engineers -- South Africa -- Eastern Cape Engineering firms -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/14102 , vital:27426
- Description: Management of an engineering consultancy unit in the Eastern Cape Province is concerned about the costs incurred by project managers and specialist engineers pursuing tender opportunities that are not feasible. Annual losses in this unit due to unsuccessful tenders amounts to R2,5 million annually, which equates to about 12% of the revenue generated by the unit. The aim of the research study is to assist the consulting engineering firm by investigating and identifying the key determinants for making the decision of whether to bid on a particular tender opportunity. The study includes an assessment of relevant literature, academia and text to investigate key factors that could influence the decision to bid on tenders from which research questions and appropriate theories were drawn. Based on the research questions and theories that emanated from the literature, the study also includes the assessment of primary data through the administration of a structured questionnaire. The questionnaire is empirically analysed within the positivistic research paradigm through the use of descriptive and inferential statistics. Conclusions are drawn and recommendations are made based on the findings of the administered questionnaire.
- Full Text:
- Date Issued: 2017
Constraints to students' participation in sport on a formalised level: implications for marketers
- Authors: Halforty, Gail Avril
- Date: 2012
- Subjects: Sports -- Physiological aspects , Marketing
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9370 , http://hdl.handle.net/10948/d1012120 , Sports -- Physiological aspects , Marketing
- Description: The rate of obesity has risen dramatically over recent years and is an epidemic in many countries. School pupils and university students are no exception to this. The negative effects physically, mentally and emotionally of being overweight are detrimental to one’s quality of life. It is therefore critical to encourage pupils and students to participate in physical activity. Formalised sport is a key component of encouraging physical activity. The habits learnt in childhood and early adulthood are often carried through for the rest of one’s life. The benefits of participating in sport need to be promoted extensively to the students, as research has shown students that participate in sport are not only healthier but achieve better academic results. This study examined the constraints to students’ participation in formalised sport. The empirical data was collected by means of a survey, using self-administered questionnaires distributed to students on the three Summerstrand campuses at the Nelson Mandela Metropolitan University in Port Elizabeth. Two hundred and eighty three usable questionnaires were received. Time and scheduling was found to be the most constraining factor to participation in sport. I am too busy with my university studies attracted the highest mean score of all the items on the questionnaire. It is recommended that: • sport organisers at NMMU emphasise to the students the benefits of regular participation in physical activity; • the effectiveness of the current NMMU sport programmes and accessibility be further investigated as only 18 per cent of the students in 2011 were participating in sport programmes at NMMU; • time management skills be taught to the NMMU students as the Time and scheduling constraint was the most profound constraint to participation in formalised sport; • NMMU academic staff work more closely with the staff at the University Sport Bureau to promote regular sport participation and to disseminate sport related information that could promote being more actively involved in sport; and • relevant introductory sport programmes and more internal leagues be offered, that gently introduce various sport codes to the students.
- Full Text:
- Date Issued: 2012
- Authors: Halforty, Gail Avril
- Date: 2012
- Subjects: Sports -- Physiological aspects , Marketing
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9370 , http://hdl.handle.net/10948/d1012120 , Sports -- Physiological aspects , Marketing
- Description: The rate of obesity has risen dramatically over recent years and is an epidemic in many countries. School pupils and university students are no exception to this. The negative effects physically, mentally and emotionally of being overweight are detrimental to one’s quality of life. It is therefore critical to encourage pupils and students to participate in physical activity. Formalised sport is a key component of encouraging physical activity. The habits learnt in childhood and early adulthood are often carried through for the rest of one’s life. The benefits of participating in sport need to be promoted extensively to the students, as research has shown students that participate in sport are not only healthier but achieve better academic results. This study examined the constraints to students’ participation in formalised sport. The empirical data was collected by means of a survey, using self-administered questionnaires distributed to students on the three Summerstrand campuses at the Nelson Mandela Metropolitan University in Port Elizabeth. Two hundred and eighty three usable questionnaires were received. Time and scheduling was found to be the most constraining factor to participation in sport. I am too busy with my university studies attracted the highest mean score of all the items on the questionnaire. It is recommended that: • sport organisers at NMMU emphasise to the students the benefits of regular participation in physical activity; • the effectiveness of the current NMMU sport programmes and accessibility be further investigated as only 18 per cent of the students in 2011 were participating in sport programmes at NMMU; • time management skills be taught to the NMMU students as the Time and scheduling constraint was the most profound constraint to participation in formalised sport; • NMMU academic staff work more closely with the staff at the University Sport Bureau to promote regular sport participation and to disseminate sport related information that could promote being more actively involved in sport; and • relevant introductory sport programmes and more internal leagues be offered, that gently introduce various sport codes to the students.
- Full Text:
- Date Issued: 2012
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