Vermiculite Carrier Solves Chelate
Application Problems.--Serious application and handling problems of iron chelates have been solved by using vermiculite as a carrier, it was reported recently. Zonolite Company, Chicago, vermiculite producers, said the micalike mineral has reduced fruit burning and leaching common when iron chelates are used alone to treat iron deficiency in plants.
A Zonolite official suggested this latest use of vermiculite may offer a solution to other chemical manufacturers seeking an effective carrier for their products.
As originally developed and used by Bersworth Chemical Company of Framingham, Mass., the chelates were in the form of a fine, dry, extremely hygroscopic powder. Applied to the soil by conventional spreader methods, the chelates produced a dust which settled on leaves and fruit, causing fruit "burn." Once in the soil, the chelates were quickly washed out and their efficiency spoiled by rain fall.
In their search for a carrier, Bersworth chemists tried vermiculite. They found the mineral readily absorbed the chelates in solution, resulting in a dry, granular material that flowed easily and was dust free. As a result, the chelates in vermiculite can be easily applied to the soil by ordinary methods. Vermiculite's multicellular structure regulates solubility by holding moisture and releasing it slowly to the soil as needed. Leaching is slow and persistent.
Addition of the carrier and packaging is done at Zonolite Company's mine and processing plant at Travelers Rest, S.C. Iron chelates in solution are absorbed by the vermiculite, approximately 27/70 mesh, and passed through a rotary dryer. The resulting greenish-brown granular mixture may be used as is, or mixed with recommended fertilizers. No special precautions, such as wearing masks, are needed.