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Leslie F. Petrik  - - - 
Top co-authors See all
Emmanuel I. Iwuoha

54 shared publications

SensorLab, Department of Chemistry, University of the Western Cape, Bellville 7535, South Africa

Tunde V. Ojumu

26 shared publications

Cape Peninsula University of Technology

Frédéric J. Doucet

24 shared publications

Council for Geoscience, 280 Pretoria Street, Silverton, Private bag X112, Pretoria 0001, South Africa, Tel. +27 0128411300

M. W. Gitari

10 shared publications

Environmental Remediation and Water Pollution Chemistry Group, Department of Ecology and Resource Management, University of Venda, Thohoyandou, South Africa

B. Amigun

6 shared publications

Sustainable Energy Futures, Natural Resources and the Environment , Council for Scientific and Industrial Research (CSIR) , PO Box 320, Stellenbosch, 7599, South Africa

Publication Record
Distribution of Articles published per year 
(2008 - 2017)
Total number of journals
published in
Publications See all
Article 4 Reads 0 Citations Synthesis and Characterization of Faujasite Zeolite and Geopolymer from South African Coal Fly Ash Nkululeko Z. N. Ndlovu, Roland N. M. Missengue, Leslie F. Pe... Published: 01 September 2017
Journal of Environmental Engineering, doi: 10.1061/(ASCE)EE.1943-7870.0001212
DOI See at publisher website
Article 0 Reads 8 Citations Synthesis of zeolite A from coal fly ash using ultrasonic treatment – A replacement for fusion step Tunde V. Ojumu, Pieter W. Du Plessis, Leslie F. Petrik Published: 01 July 2016
Ultrasonics Sonochemistry, doi: 10.1016/j.ultsonch.2016.01.016
DOI See at publisher website PubMed View at PubMed
Article 0 Reads 0 Citations Geochemical modeling of brine remediation using accelerated carbonation of fly ash Muriithi Nyambura Grace, Petrik Felicia Leslie, Doucet Jules... Published: 23 February 2015
DESALINATION AND WATER TREATMENT, doi: 10.1080/19443994.2014.1003607
DOI See at publisher website
Article 0 Reads 1 Citation Distributional Fate of Elements during the Synthesis of Zeolites from South African Coal Fly Ash Pieter W. Du Plessis, Tunde V. Ojumu, Ojo O. Fatoba, Richard... Published: 23 April 2014
Materials, doi: 10.3390/ma7043305
DOI See at publisher website ABS Show/hide abstract
The synthesis of zeolites from South African coal fly ash has been deemed a viable solution to the growing economical strain caused by the disposal of ash in the country. Two synthesis routes have been studied thus far namely the 2-step method and the fusion assisted process. Fly ash contains several elements originating from coal which is incorporated in the ash during combustion. It is vital to determine the final destination of these elements in order to unveil optimization opportunities for scale-up purposes. The aim of this study was to perform a material balance study on both synthesis routes to determine the distributional fate of these elements during the synthesis of zeolites. Zeolites were first synthesized by means of the two synthesis routes. The composition of all raw materials and products were determined after which an overall and elemental balance were performed. Results indicated that in the 2-step method almost all elements were concentrated in the solid zeolite product while during the fusion assisted route the elements mostly report to the solid waste. Toxic elements such as Pb, Hg, Al, As and Nb were found in both the supernatant waste and washing water resulting from each synthesis route. It has also been seen that large quantities of Si and Al are wasted in the supernatant waste. It is highly recommended that the opportunity to recycle this liquid waste be investigated for scale-up purposes. Results also indicate that efficiency whereby Si and Al are extracted from fused ash is exceptionally poor and should be optimized.
Article 1 Read 12 Citations Synthesis of Zeolites Na-P1 from South African Coal Fly Ash: Effect of Impeller Design and Agitation Dakalo Mainganye, Tunde Victor Ojumu, Leslie Petrik Published: 16 May 2013
Materials, doi: 10.3390/ma6052074
DOI See at publisher website ABS Show/hide abstract
South African fly ash has been shown to be a useful feedstock for the synthesis of some zeolites. The present study focuses on the effect of impeller design and agitation rates on the synthesis of zeolite Na-P1 which are critical to the commercialization of this product. The effects of three impeller designs (4-flat blade, Anchor and Archimedes screw impellers) and three agitation speeds (150, 200 and 300 rpm) were investigated using a modified previously reported synthesis conditions; 48 hours of ageing at 47 °C and static hydrothermal treatment at 140 °C for 48 hours. The experimental results demonstrated that the phase purity of zeolite Na-P1 was strongly affected by the agitation rate and the type of impeller used during the ageing step of the synthesis process. Although zeolite Na-P1 was synthesized with a space time yield (STY) of 15 ± 0.4 kg d−1m−3and a product yield of 0.98±0.05 g zeolites/g fly ash for each impeller at different agitation speeds, zeolite formation was assessed to be fairly unsuccessful in some cases due the occurrence of undissolved mullite and/or the formation of impurities such as hydroxysodalite with the zeolitic product. This study also showed that a high crystalline zeolite Na-P1 can be synthesized from South African coal fly ash using a 4-flat blade impeller at an agitation rate of 200 rpm during the ageing step at 47 °C for 48 hours followed by static hydrothermal treatment at 140 °C for 48 hours.
Article 0 Reads 3 Citations Waste Minimization Protocols for the Process of Synthesizing Zeolites from South African Coal Fly Ash Pieter W. Du Plessis, Tunde V. Ojumu, Leslie F. Petrik, Piet... Published: 29 April 2013
Materials, doi: 10.3390/ma6051688
DOI See at publisher website ABS Show/hide abstract
Production of a high value zeolite from fly ash has been shown to be an avenue for the utilization of South African fly ash which presently constitutes a huge disposal problem. The synthesis of zeolites Na-P1 and analcime on a micro-scale has been successful and preliminary investigation shows that scale-up synthesis is promising. However, the post-synthesis supernatant waste generated contains high levels of NaOH that may constitute a secondary disposal problem. A waste minimization protocol was developed to reduce the volume of waste generated with a view to enhancing the feasibility of the scale synthesis. Series of experiments were conducted in 100 mL jacketed batch reactors. Fly ash was reacted with 5 Mol NaOH on a 1:1 mass basis during the aging step, followed by hydrothermal treatment in which ultrapure water was added to the slurry. This study shows that by re-introducing the supernatant waste into the experiments in such a way that it supplies the required reagent (NaOH) for the zeolite synthesis, zeolite Na-P1 and analcime can be synthesized. It also shows that the synthesis process can be altered to allow up to 100% re-use of the supernatant waste to yield high value zeolitic products. This study effectively constructed two protocols for the minimization of waste generated during the synthesis of zeolites from South African coal fly ash. This result could be used to establish a basis for legal and environmental aspects involved in the commission of a full-scale plant synthesizing zeolites NaP1 and analcime.