In the agricultural field it is often necessary to dose with traces of heavy metals e.g. Fe – Mn – Zn used as micronutrients. The complexing metal properties of StarLig lignosulfonate products with high solubility and low cost, create an ideal carrier for this purpose. Depending on the process requirements, LignoStar can provide several different lignosulfonate solutions for this application.
In granular micronutrients, they function as conditioning agents. Benefits obtained by the addition of lignin during the granulation process include improved granulation and reduced in-process chute plugging. Granules conditioned with lignins have increased strength, reduced dustiness, and are less prone to caking or pile set. As a result of their improved physical properties, micronutrient granules conditioned with lignin also generate less dust upon handling.
In liquid formulations, lignins act as complexing agents keeping micronutrients in an available form under pH conditions which would normally cause insolubilization. Complexed micronutrients made from lignins are easily applied and readily available to the plant. When applied as foliar sprays, they do not cause leaf burn (i.e. are non phytotoxic). When used in soil treatment, they maintain availability longer than if the elements are applied alone.
Complexed micronutrients made from lignin are weaker than those made from amine-based complexing agents such as EDTA, often an advantage for micronutrient availability to the plant. They are compatible with most pesticide formulations. Their use in phosphate-based fertilizers, however, depends on the specific formulation of interest, and pre-testing is suggested. Lignins are classified by the EPA/FDA as non-toxic and are easy to handle and use. Their environmental friendliness makes them a “natural” choice in both granular and liquid products. Research to develop improved lignins for use in micronutrients is on-going and includes products with improved borate and phosphate tolerances.