BTC offers under the brand name Trilon® a broad product range of high performance and innovative complexing agents, also known as chelating agents. Chelating agents are able to complex metal ions. Chelating agents are able to prevent the deleterious impact of metal ions during the bleaching processes within the paper and pulp industry. The presence of free metal ions, such as iron, copper, manganese and magnesium, reduces efficiency of the bleaching step.
Properties of Trilon® chelating agents used as bleach stabilizers in paper & pulp industry
BTC’s Trilon® chelating agents belong mainly to the class of amino carboxylates which are organic complexing agents. They are available
- in powder or in liquid form, or as granules;
- as pure acid version or salt version;
- in very high purity as high-quality grades for special applications
Chelating agents differentiate in the performance of binding capacity to form complexes and in the stability of the formed complexes. Trilon® grades form typically 1:1 complexes. The high stability of these compounds makes them ideal for many industrial processes. They show a very good solubilisation property of the formed complexes.
Based on the used amino carboxylic acid the following organic chelating additives are available:
- Trilon® B grades; ethylenediamine tetraacetic acid, or Na-salt (EDTA)
- Trilon® D grades; N-(hydroxyl ethyl)-ethylenediamine triacetic acid (HEDTA)
- Trilon® M grades; methylglycine diacetic acid (MGDA)
Trilon® M grades represent the newest generation of complexing agents. Based on methylglycine diacetic acid the product provides a very good chelating performance in addition with a readily biodegradability property. The excellent ecological and toxicological profile of Trilon® M has been verified in various repeated studies.
Applications of Trilon® chelating agents used as bleach stabilizers in paper & pulp industry
Chelates are particularly important in the treatment of mechanical pulps were heavy ions in the lignin have a detrimental effect on the effectiveness of bleaches. In mechanical pulping, chelates are added separately and combined with sodium hydrosulphite bleaching compounds. Bleached thermomechanical (TMP) pulps and chemo-thermomechanical (CTMP) pulps use hydrogen peroxide and sodium hydrosulphite and are in need of chelates.
Manufacturing of pulp- and paper
In the manufacturing of pulp and paper Trilon® grades are used
- to degrade the uncomplexed metal ions which catalyse the degradation of hydrogen peroxide, ozone and oxygen.
- to increase the efficiency and durability of the bleaching agents,
- to enhance the effectiveness of bleach systems,
- to achieve higher brightness levels,
- to control scaling.