Production of biogasoline from waste cooking oil as an environmentally friendly alternative liquid fuel

A Dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa, in fulfillment for the degree of Master of Science Johannesburg, 20th of September 2017Energy is an important utility to human kind. Since the beginning of human civilization, human beings have become acquainted with travelling and transportation of goods. The use of conventional energy fuels for automobile engines is no longer sustainable due to finite crude oil reserves available in the world, of which many are facing the crisis of being depleted. The use of conventional fuels is a major contributor to environmental concerns such as global warming. Therefore there is an urgent need to explore alternative sources of fuel energy that are sustainable and environmentally friendly. The production of biofuels has been receiving increased academic and industrial attention as practical alternative fuel sources that can partially or completely replace conventional fuels. A study of the production of biogasoline from waste cooking oil as an alternative and re-usable source of liquid fuel was conducted in this project. This work focused on the variety of parameters that would deliver the optimum conversion and yield of biogasoline. The waste cooking oil was converted through catalytic hydrocracking in the presence of an acid activated Ni-Mo/Al2C>3 catalyst and constant hydrogen gas pressure of 0.5 kPa. A number of Ni-Mo/A^Oa catalysts were synthesized with varying Ni-loadings from 5-25 wt. % and calcination temperatures from 300 °C to 700 °C. The catalysts were characterised using ICP-OES, TGA, BET, SEM, FT-IR and Raman spectroscopy. Catalyst characterisation results revealed that the catalyst with 5 wt. % Ni possessed the greatest thermal strength, with the maximum BET surface area of 61.61 m /g and high dispersion of the active species in the catalyst. The optimal calcination temperature range for this catalyst was found from 500 °C to 600 °C. The effects of reaction temperature, reaction time, catalyst: oil ratio, catalyst calcination temperature and Ni-loading (wt. %) were investigated. The highest percentage of produced biogasoline was 59.50 wt. % at a reaction temperature of 250 °C, catalyst: oil ratio of 1:75, reaction time of 1 hr with a catalyst loaded with 5 wt. % Ni and calcinated at 300 °C. The use of stainless steel reactors that can handle higher reaction temperatures and pressure is recommended for future studies that will allow more severe cracking of the raw material into lighter hydrocarbons. The Ni-Mo/AhCT catalyst can also be modified with boron or fluorine to enhance its catalytic activity.MT 201

Social assistance strategies as means of addressing poverty: lessons for South Africa

Poverty is a daily reality which a majority of South Africans live with. Social security in the form of cash grants has been the main poverty reduction instrument, albeit with limited success. The thesis aims to propose improvements which can be made in the government’s current social protection system and formulate alternative directions towards reducing poverty. An overview of the three most researched social security strategies around the world (i.e. Nordic, Latin American, and U.S. models) revealed two dominant instruments: conditionality and universalism. If applied in South Africa, universalism may be costly and unsustainable unless the right funding method is used. Attaching education and health attainment conditions to an adult grant would be inefficient and even burdensome to recipients. In terms of child grants, there is little evidence to suggest that the demand for and private levels of investment in education and health are insufficient. Therefore attaching health and education conditions to social grants may only serve to highlight the severe supply side inefficiencies in South Africa. Attaching marriage as an alternative condition may disadvantage poor and needy beneficiaries as marriage is an expensive institution in South Africa. Furthermore, enforcing the marriage condition would violate the constitutional rights of recipients who do not necessarily place a high value on the institution. To strengthen the poverty reduction efficiency of social grants and reduce dependency, the thesis suggests that social cash grants, regardless of whether universal and/or conditional or neither, should be temporary and used in conjunction with other strategies which encourage inclusive economic growth. Social assistance alone will not reduce poverty and ultimately, inclusive economic growth remains a more viable approach to reducing poverty. How to achieve the required inclusive economic growth in South Africa therefore provides further research opportunities

Lebollo la basadi

Byale rites of Tsatane by A. Mampuru (written in Noord-Sotho). Forms part of van Warmelo Collection housed at the University of Pretoria

Does seasonal variation influence the phytochemical and antibacterial properties of Carpobrotus edulis?

Carpobrotus edulis L. (family Aizoaceae) has been used by locals over the years to treat microbial infections. Extracts of varying polarities were prepared from the leaf debris and filtrate of a spring andan autumn harvest of C. edulis. Thin layer chromatography was used to analyze the phytocompounds of the extracts as well as to assay the plant for antioxidant compounds. The spring harvest showedequal distribution of the phytochemicals within the leaf debris and the filtrate, but there was a high prevalence of phytocompounds within the leaf debris extracts of the autumn sample. An antioxidantcompound was intensely pronounced in the autumn extracts of intermediate polarity and in the polar extract. The plant was evaluated for antibacterial activity against Escherichia coli, Enterococcusfaecalis, Pseudomonas aeruginosa and Staphylococcus aureus by using a two-fold serial microdilution method as well as bioautography. The spring extracts were more potent against all test organisms,having MIC values that were lower than the autumn extracts. When taking the total activity of each extract into account, the autumn extracts showed higher efficacy than the extracts from the springsample. The antibacterial activity observed in the extracts of both seasons somewhat validated the ethnomedicinal use of C. edulis

Determination of Leachable Vanadium (V) in Sediment

A method for speciation of vanadium in solid samples was developed for quantification of vanadium(+5) in solid samples of sediment Certified Reference Materials (CRM) PACS-2 and MESS-3 (Trace Elements in Sediments) of known total vanadium content. The method relies on a classical analytical chemistry procedure based on leaching water-insoluble vanadium(+5) compounds fromthe solid state into solution using Na2CO3 followed by electrothermal atomic absorption spectrometry (ET-AAS) detection. The total amount content of vanadium was determined after complete digestion of the CRMs and found to be 132 ± 5 and 245 ± 12 μg g–1 in PACS-2 and MESS-3, respectively, in good agreement with the certified values of 133 ± 6 μg g–1 and 243 ± 12 μg g–1. The concentrations of vanadium(+5) were determined to be 25 ± 3 μg g–1 and 13 ± 2 μg g–1 in PACS-2 and MESS-3, respectively. These results were verified by the method of standard additions for which quantitative recoveries (100 ± 2 and 97 ± 3 %, one standard deviation, n = 3) were obtained for spikes added to PACS-2 and MESS-3, respectively. Approximately 18.8 % of the total vanadium content of PACS-2 and 5.3 % in MESS-3 is in the form of vanadium(+5) species.KEYWORDS Certified reference materials, vanadium(+5) speciation, electrothermal atomic absorption spectrometry

Determinants of school success in disadvantaged environments

Learners in disadvantaged environments are less likely to do well at school. Yet some of the most successful schools operate in such environments. The purpose of this study was to establish the relative influence of various determinants of school success in disadvantaged environments. To this end literature study was done in two phases. The first resulted in a taxonomy of success factors, which was then used to guide the second in-depth phase. Thereafter an empirical study was done, involving qualitative field work at four successful schools in disadvantaged environments. Empirically it was discovered that there is no single most important success factor because all success factors are interrelated and interdependent. The over-arching success factor discovered in this study which was involvement of all stakeholders.EducationM.Ed

Mongwalelo wa sefela sa Serote : ‘a re thabeng re rete’ (Difela tša kereke, 2010)

Bangwadi ba Bathobaso ba difela tša kereke ba hueditšwe ke bangwadi ba baruti (ba Matoitšhi ba Kereke ya Lutere ya Berlin) ge ba tlo ngwala difela. Ka go realo ke ba mathomo ba go ngwala poleloopelwa ya Sepedi. Ka lebaka la gore baruti ba Matoitšhi ba be ba sa tsebe melao ya go laola metara wa Sepedi, ba thomile go hlama difela tša bona ka mokgwa wo difela tša Setoitšhi di hlamilwego ka wona. Bangwadi ba difela ba Bapedi le bona ba ba šala morago bjalo. Ka go realo go ka thwe mothopomogolo wa khuetšo ya sebjalebjale dingwalong tša Sepedi ke mediro ya kereke ya mathomothomo. Le ge go le bjalo bohlokwa bjo bja kgolo ya theto ka tsela ya difela dingwalong tša Sepedi ga se bja šalwa morago le go gatelelwa ke basekaseki. Maikemišetšo a taodišwana ye ke go lekola, ka botlalo, mongwalelo wa difela ka go nepiša sefela sa Serote sa 147 sa go bitšwa ‘A re thabeng re rete’ (Difela tša kereke 2010:130). Go yo tsitsinkela ka fao mongwalelo o tšwetšago pele kgegeo. Ka mantšu a mangwe, go yo sekasekwa dipharologantšho tša mongwalelo tše di tšwetšago pele kgegeo. Go tlo lemogwa gore kgegeo yeo e bonagatšwa ka modiro wa Selalelo se Sekgethwa sa Morena seo se hlalošwago ka tsela ya khuduego/maikutlo go tšwetša pele morero wa mongwadi/moopedi wa sefela se ka ge bjale Selalelo e le selo seo Bakriste ba se hlomphago (se lebane le tshwarelo ya dibe tša bona), go ya ka fao se hlalošwago ka gona ka tsela yeo ya kgegeo.Black composers of church hymns were influenced by German pastors of the Berlin Lutheran Church to do so. In other words, these pastors were the first composers to write the Sepedi language in the form of music; because they did not know the rules that control the Sepedi meter, the writers started to compose their hymns in the way that the German hymns were patterned. Therefore, one might argue that the main source of modern influence in Sepedi literature lies in the workings of the very first hymns of the said church. Nevertheless, the importance of the development of poetry in the form of hymns in the Sepedi literature has not been followed up and emphasised by reviewers. The aim of this article is to survey thoroughly the style of writing hymns, by discussing Rev Serote’s hymn number 147, entitled ‘A re thabeng re rete’ (Difela tša kereke 2010:130). The scrutiny will examine the way in which style depicts irony in the very hymn. In other words, the investigation considers especially the characteristics of style that indicate and develop irony in the work. It will be shown that the irony becomes clear during the service of Baptism which is expressed by way of emotions to develop the author’s aim, as this sacrament is something that Christians respect (it goes hand in hand with the forgiveness of their sins).http://www.ve.org.zaam201

In vitro evaluation of the antifungal activity of Sclerocarya birrea extracts against pathogenic yeasts

The antifungal activity of Sclerocarya birrea which is used in South African traditional medicine for the treatment of skin diseases was evaluated against three yeasts; Candida parapsilosis, Cryptococcusalbidus and Rhodoturula mucilaginosa. Barks of S. birrea were extracted with hexane, dichloromethane (DCM), chloroform, ethyl acetate, acetone, methanol and ethanol and tested against these three yeasts.The antifungal assay was performed by the microdilution technique and bioautography. Thin layer chromatography was used to analyze the phytocompounds of the extracts as well as to assay the plantfor antioxidant compounds. More compounds with antioxidant activity were observed in polar separation system, ethyl  cetate:methanol:water (EMW). All test organisms were resistant against all non-polar extracts. Acetone, ethanol and methanol S. birrea extracts had average MIC values of 0.39, 0.22 and 0.27 mg/ml, respectively. C. albidus was the most sensitive organism with an average MIC value of 0.17 mg/ml. Average total activity was highest for methanol (387 ml/g) followed by ethanol (363 ml/g) and acetone (299 ml/g) bark extracts. Acetone and methanolic bark extracts were more active in EMW system at Rf values of 0.07, 0.32 and 0.70 against C. parapsilosis. The results showed that the plant could be further explored for possible antifungal agents and provides preliminary scientific validation of the traditional medicinal use of this plant

Alteration of Bax-to-Bcl-2 ratio modulates the anticancer activity of methanolic extract of Commelina benghalensis (Commelinaceae) in Jurkat T cells

Stem extracts of Commelina benghalensis (Linn.), although not extensively documented, are frequently used in traditional medicine for the treatment of ailments such as skin malformations and outgrowths. Accordingly, the study was aimed to investigate possible molecular mechanisms that are associated with the potential anti-carcinogenic property of this agrofield weed. Jurkat T cells were exposed to different concentrations (0-600 ug/ml) of the crude methanolic extract of C. benghalensis to evaluate their growth inhibitory and apoptosis inducing effects. The extract elicited a dose- and time-dependent inhibition of cell proliferation, followed by a concomitant decrease in cell viability. The observed cytotoxicity was linked to the induction of apoptosis as determined by morphological and biochemical features known to be associated with the advent of apoptosis. Real time quantitative RT-PCR and Western blot analyses of Bax, Bcl-2 and p53 exhibited aberrant expression profiles of these genes under various treatment conditions. Taken together, the data suggest that the crude methanolic extract of C. benghalensis contains bioactive compounds that may be beneficial in the treatment of malignant growths, and that this apparent antineoplastic activity is a consequence of dysregulated expression of apoptosis-responsive genes. These observations could provide a credible scientific justification upon which the ethnopharmacological utilisation of C. benghalensis is founded