Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Mesoporous silica recovery from phlogopite by aqua regia leaching
Dissertation (MEng)--University of Pretoria, 2015.
Saved in:
| Other Authors: | |
|---|---|
| Format: | Thesis |
| Language: | English |
| Published: |
University of Pretoria
2016
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613562126467072 |
|---|---|
| access_status_str | Open Access |
| author2 | Du Plessis, B.J.G.W. |
| author_browse | Du Plessis, B.J.G.W. |
| author_facet | Du Plessis, B.J.G.W. |
| collection | Thesis |
| dc_rights_str_mv | © 2016 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. |
| description | Dissertation (MEng)--University of Pretoria, 2015. |
| format | Thesis |
| id | oai:repository.up.ac.za:2263/56122 |
| institution | University of Pretoria (South Africa) |
| language | English |
| last_indexed | 2026-06-10T12:38:06.885Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository |
| publishDate | 2016 |
| publishDateRange | 2016 |
| publishDateSort | 2016 |
| publisher | University of Pretoria |
| publisherStr | University of Pretoria |
| record_format | dspace |
| source_str | UPSpace — University of Pretoria Institutional Repository |
| spelling | oai:repository.up.ac.za:2263/56122 Mesoporous silica recovery from phlogopite by aqua regia leaching Du Plessis, B.J.G.W. u29073937@tuks.co.za Venter, Iwouda UCTD Phlogopite Aqua regia Surface area Acid leaching Engineering, built environment and information technology theses SDG-09 Engineering, built environment and information technology theses SDG-12 Dissertation (MEng)--University of Pretoria, 2015. Phlogopite is a mineral found in the Phalaborwa complex, which is mined in abundance and has little to no industrial use. Phlogopite in its raw form consists of between 40 50% silicon. Previous studies have yielded various forms of silica through acid leaching of phlogopite. The aim is to leach phlogopite with aqua regia to obtain mesoporous silica with the maximum specific surface area possible. Interest in mesoporous silica utilization has greatly increased in areas such as catalysis, polymer reinforcement, adsorption and medical uses. Phlogopite is leached in a temperature controlled batch reactor with aqua regia, nitric acid and hydrochloric acid to recover the remaining silicon product. The leaching conditions are varied in order to obtain the silicon oxide with the largest specific surface area. The leaching conditions such as acid concentration, nitrate ratio, leaching time, temperature, solid to liquid ratio, stirring speed and particle size are varied to determine the effects on the surface area. With aqua regia as leaching agent the maximum specific surface area of 99.41% silica achieved was 515 m²/g at acid concentration of 8.40 M, nitrate ratio of 0.64, leaching time of 12 hrs and leaching temperature at 50 ?C. This experiment provided mesoporous silica with average pore width of 2.62 nm and average pore volume of 0.36 cm³/g. Similar specific surface area values were achieved with 6.33 M nitric acid, leaching time of 6 hrs and leaching temperature at 60 ?C. A regression (R²= 0.90) was developed which can accurately estimate the specific surface area of the recovered silica with the known acid concentration, nitrate ratio, leaching time and temperature. tm2016 mi2026 Chemical Engineering MEng Unrestricted SDG-09: Industry, innovation and infrastructure SDG-12: Responsible consumption and production 2016-07-29T11:02:14Z 2016-07-29T11:02:14Z 2016-04-07 2015 Dissertation Venter, IZ 2015, Mesoporous silica recovery from phlogopite by aqua regia leaching, MEng Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/56122> A2016 http://hdl.handle.net/2263/56122 en © 2016 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria |
| spellingShingle | UCTD Phlogopite Aqua regia Surface area Acid leaching Engineering, built environment and information technology theses SDG-09 Engineering, built environment and information technology theses SDG-12 Mesoporous silica recovery from phlogopite by aqua regia leaching |
| title | Mesoporous silica recovery from phlogopite by aqua regia leaching |
| title_full | Mesoporous silica recovery from phlogopite by aqua regia leaching |
| title_fullStr | Mesoporous silica recovery from phlogopite by aqua regia leaching |
| title_full_unstemmed | Mesoporous silica recovery from phlogopite by aqua regia leaching |
| title_short | Mesoporous silica recovery from phlogopite by aqua regia leaching |
| title_sort | mesoporous silica recovery from phlogopite by aqua regia leaching |
| topic | UCTD Phlogopite Aqua regia Surface area Acid leaching Engineering, built environment and information technology theses SDG-09 Engineering, built environment and information technology theses SDG-12 |
| url | http://hdl.handle.net/2263/56122 |