SU1523038A3 - Method of producing granulated herbicide composition - Google Patents

Abstract

A process of preparing a solid herbicidal formulation containing a high concentration of a bipyridylium diquaternary salt, which comprises injecting a solution of the bipyridylium salt into a heated fluid bed of a particulate carrier, so that the bipyridylium salt is deposited on to the carrier.

Description

. The invention relates to agriculture, namely to a method for producing a granular herbicidal composition containing 1,1-dimethyl-4,4-bipyridylium dichloride (paraquat dichloride) as an active compound.

The purpose of the invention is to improve the operational properties of the drug.

The method according to the invention can be carried out in a conventional fluidized bed reactor. The reactor is a tubular or cylindrical vessel fixed on a vertical axis and having a perforated plate fixed in its lower end. Particles of solid material to be liquefied

cm

they are poured into the reactor, and they lie on a perforated plate. The gas used for liquefaction is fed through a perforated plate under pressure, and it passes upwards through the material. It is preferable to maintain the pressure from the downstream side of the perforated plate slightly below atmospheric pressure outside the apparatus, for example, using a fan installed at the outlet of the air stream from the reactor. This prevents the entrainment of small particles from the apparatus. Preferably, the flow of air from the reactor through the apparatus (e.g., a cyclone) is passed through to collect fine dust particles that are too small to remain in the fluidized bed and that are trapped by the air flow passing through the reactor. An aqueous solution of the bipyridylium salt may be introduced into the fluidized bed with the aid of spraying through one or more spray nozzles. They can be mounted, for example, on a reactor wall with a fluidized bed or in the center of a perforated plate. The supply of the solution can be carried out using a dosing

the pump

one

Example. In the process, granulated calcium chloride or sodium chloride is used as a solid dispersant. Paraquat dichloride with a concentration of 360 g / l is used as the bipyridylium salt. In the experiment with sodium chloride, a surface active agent is mixed, which is a condensate of 7-8 moles of ethylene oxide with p-nonylphenol and having a trade name Lissapol IC, with a solution of paraquat dichloride in the ratio It4 and sprayed as a homogeneous mixture. The products from both experiments are homogeneous, free flowing, non-nestlike granules having an average particle size of 1 to 2 mmi.

In tab. 1 and 2 show the conditions for the preparation and the yield of granulars. The composition of the herbicide composition is higher; in experiments 3 and 4, an aqueous solution of paraquat dichloride is used at a concentration of 200 g / l.

From the results table. 2 it follows that the proposed method allows to obtain a granular herbicidal composition containing 27.8-29% by weight of paraquat. The known method of obtaining the herbicidal composition, which consists in mixing an aqueous solution of paraquat dichloride with salt, which is able to form Kristapplorates, allows to obtain compositions with a relatively low content

.Im active compound "

Claims (1)

 1 formula invented A method for producing a granulated herbicidal composition, comprising treating a solid granulated diluent with a solution of the active compound of the bipyridy quaternary salt of 1,1-dimethyl-4,4-bipyridylium dichloride (paraquat dichloride) of the formula Hjc-n  m-SNZ 2S1 differs by the fact that, in order to improve the performance properties of the preparation, calcium chloride or sodium chloride is used as a diluent and the treatment is carried out with a solution of the active compound in a concentration of 200 or 360 g / l in water or in an aqueous solution of paranonylphenol ethoxylated 7-8 mol ethylene oxide, in addition ratio: 4 or 1:10 with the active compound, by spraying a solid diluent in a fluidized bed at a temperature of 84-93 C layer and a ratio of the active substance to a diluent of 0.45-0.5331. table 2