| Title: |
Synthesis, characterisation and evaluation of slow nitrogen release organic soil conditioners from South African technical lignins |
| Authors: |
Tyhoda, Luvuyo |
| Contributors: |
Liebner, Falk; Rypstra, Tim; Rozanov, Andrei Borisovich; Stellenbosch University. Faculty of AgriSciences. Dept. of Forest and Wood Science. |
| Publisher Information: |
Stellenbosch University |
| Publication Year: |
2008 |
| Collection: |
Stellenbosch University: SUNScholar Research Repository |
| Subject Terms: |
Nitrogen fertilizers -- South Africa; Waste products as fertilizer -- South Africa; Lignin; Soil chemistry -- South Africa; Dissertations -- Wood science |
| Description: |
Dissertation (PhD) -- University of Stellenbosch, 2008. ; ENGLISH ABSTRACT: Today there is renewed interest in using technical lignins and similar ligneous materials as soil fertilising materials as they are available in large quantities from the pulping and agricultural industries. In addition, excessive application of inorganic fertilisers results in ground water pollution, especially in sandy soils through leaching of nitrogen. Lignin is an important precursor of humic material in soils and with modification, can be used as a raw material to produce slow nitrogen release fertilisers (N-lignins). This can be done using a reaction process called oxidative ammonolysis. This process has been developed over the years by the Institute of Plant and Wood Chemistry of the Technical University of Dresden in Germany, and a patent has been obtained for an ambient pressure based, oxidative ammonolysis. The patented product obtained from this process which is prepared from low-grade brown coal (due to its similarity to lignin) is trade named NOVIHUM™. It is a slow nitrogen release and long lasting organo-mineral fertiliser which has similar properties as natural humic substances. This project focussed on the characterisation and use of industrial residues such as technical lignins and similar ligneous materials which are produced by the South African pulping and agricultural industries, and on the production of N-lignins according to the patented NOVIHUM™ technology. Three technical lignins, one derived from the sulphite pulping process (a calcium lignosulphonate), the second from sugar cane bagasse (Sucrolin), and a third a, partially stripped sugar cane bagasse (a lignocellulosic residue with a low lignin content) were subjected to oxidative ammonolysis. A Kraft lignin, lndulin AT, from Westvaco, USA was used for comparison. The N-lignin products obtained were characterised and evaluated in plant growth trials. ; AFRIKAANSE OPSOMMING: Daar is vandag hemude belangstelling in tegniese ligniene en soortgelyke lignienagtige ... |
| Document Type: |
thesis |
| File Description: |
224 leaves : illustrations; application/pdf |
| Language: |
English |
| Relation: |
https://hdl.handle.net/10019.1/50769 |
| Availability: |
https://hdl.handle.net/10019.1/50769 |
| Rights: |
Stellenbosch University |
| Accession Number: |
edsbas.3C4130CB |
| Database: |
BASE |