AU2019280024A1

AU2019280024A1 - Composition for reducing water hardness and pH and enhancing the efficacy of agricultural chemicals

Info

Publication number: AU2019280024A1
Application number: AU2019280024A
Authority: AU
Inventors: Allan Harvey Spencer
Original assignee: Australian Adjuvants Pty Ltd
Current assignee: Australian Adjuvants Pty Ltd
Priority date: 2018-12-19
Filing date: 2019-12-12
Publication date: 2020-07-09

Abstract

An aqueous composition for reducing water hardness and/or water pH and/or enhancing the efficacy of agricultural chemicals comprising: an effective amount of casein acid dissolved in water; and a solubilising amount of one or more ethoxylated cocoamines.

Description

Composition for reducing water hardness and pH and enhancing the efficacy of agricultural chemicals

Field of the invention

[0001] The present invention relates to a composition for reducing water hardness and/or pH and/or enhancing the efficacy of agricultural chemicals. In particular, the present invention relates to an aqueous composition for use in the application of agricultural chemicals.

Background of the invention

[0002] In this specification unless the contrary is expressly stated, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge; or known to be relevant to an attempt to solve any problem with which this specification is concerned.

[0003] Typically, water is combined with, and used as a carrier for, agricultural chemicals (e.g. pesticides, fungicides, herbicides, fertilizers, micronutrients, growth hormones), sometimes referred to as 'agrochemicals', prior to application (e.g. using sprayers) on plants and/or soil to enhance crop performance and/or control pests. It is generally desirable to use high quality water to minimise any adverse impact from impurities in the water on the activity and/or efficacy of agricultural chemicals.

[0004] The water used to spray agricultural chemicals (also known as agrochemicals), sometimes referred to as 'spray water' or 'spray tank water', generally varies widely in terms of its source and quality. Such water is usually supplied from boreholes, open wells and natural sources (e.g. rivers or water streams), but may also be municipally treated water. Spray water is usually'hard water'and can vary in pH. The use of hard water and/or alkaline water, in particular, with agricultural chemicals may reduce the activity and/or efficacy of those chemicals.

[0005] Hard water is water that contains high concentrations of mineral salts (above 120ppm and very hard above 250ppm) such as calcium and magnesium carbonates (e.g. bicarbonates, carbonates, chlorides and sulfates). Water often picks up these minerals when passing through materials such as limestone and chalk. Calcium and magnesium may also increase the pH of water. The water supply for agricultural use is usually alkaline (i.e. has a high pH of greater than 7.0). It has been found that hard water and/or alkaline water, particularly borehole water, may reduce the activity and/or efficacy of many agricultural chemicals.

[0006] Hard water may have an adverse effect on the properties of agricultural chemicals. For example, high concentrations of mineral salts in water may interact with the agricultural chemicals. This may lead to the precipitation of the agricultural chemicals (i.e. the formation of solids out of solution), which results in the agricultural chemicals being less effective or entirely ineffective. Further, the use of hard water with agricultural chemicals may block the pipe lines, drip irrigation lines and/or sprinkler nozzles used to administer those chemicals over a period of time. This may disrupt the uniform supply of the agricultural chemicals to all plants and/or soil, and result in time consuming and costly delays.

[0007] In respect of alkaline water, generally, it has been found that most agricultural chemicals are most effective and stable when used at an acidic pH, for example, between the range of 4 to 6. Many agricultural chemicals become less effective or ineffective when they are mixed with spray water that is alkaline. This may occur as a result of a chemical reaction called alkaline hydrolysis. The extent of the alkaline hydrolysis may depend on the spray water's pH and temperature, the agricultural chemical, and the time of interaction between the spray water and agricultural chemical. Importantly, the rate of hydrolysis will be greater for spray water with higher pHs, which may lead to the agricultural chemicals having a half-life as short as from a few minutes to a few hours.

[0008] Further, agricultural chemicals that are not "fully loaded" are particularly susceptible to hard water and/or alkaline water, and typically require assistance to be fully effective. "Fully loaded" in this context means a composition that contains enough other materials, in addition to the active, such as adjuvants and/or surfactants, for the composition to work without the addition of other products. Agricultural chemicals, even in a "fully loaded" product, do not work or work with a greatly reduced efficacy if hard water and/or alkaline water is used to dilute the agricultural chemicals in a spray tank. Hard water and/or alkaline water can even precipitate out agricultural chemicals especially when used in combination with other products.

[0009] Accordingly, spray water usually requires treatment before it is combined with agricultural chemicals for applying on plants and/or soil. Such treatment enables the activity and/or effectiveness of the agricultural chemicals to be preserved. There are a number of prior art compositions which have been used to treat spray water in an attempt to reduce its water hardness and/or pH. One disadvantage of these prior art treatment compositions used for pH adjustment and penetration is that they typically contain propionic acid, which causes a noxious smell (e.g. LI 700 from Loveland Products or Collide 700 from Nufarm Australia). Products containing liquid ammonium sulphate from several suppliers (e.g. Liase from Nufarm Australia) are also used for reducing water hardness and/or water pH.

[0010] The main disadvantage of these prior art treatment compositions is that they are typically oil and ester based, and are thus largely water-insoluble which can lead to the formation of emulsions. Accordingly, it is more difficult for these compositions to have a comprehensive uniform effect on reducing the water hardness and/or water pH of spray tank water. Further examples of water-insoluble compositions used to treat water hardness include Hot-Up and Outright 770 from Victorian Chemical Company, and Kombo 950 from Alphakem. These compositions may also reduce water pH, however, typically they only reduce the water pH to about pH 7, which may still be too alkaline for some agricultural chemicals.

[0011] There is a need for an aqueous composition for treating spray water to reduce its water hardness and/or pH in order to minimise its adverse effects on the activity and/or efficacy of agricultural chemicals. Additionally, there is a need for such an aqueous composition to not contain propionic acid in order to avoid a noxious smell when administered to plants and/or soil.

Summary of the invention

[0012] Disclosed herein is an aqueous composition for reducing the water hardness and/or water pH of spray water and/or enhancing the efficacy of agricultural chemicals. The composition comprises of an effective amount of casein acid dissolved in water, and one or more ethoxylated cocoamines. The casein acid has properties which allow it to reduce water hardness and/or water pH. However, it is water-insoluble which makes it difficult to solubilise and dissolve into an aqueous solution, and to have this effect.

[0013] However, ethoxylated cocoamines, preferably coco propyl diamine ethoxylated surfactants, have been found to be able to increase the water solubility of casein acid and solubilise it into water. This allows the casein acid to treat spray water by reducing its water hardness and/or water pH. This results in agricultural chemicals which are used with such spray water for administration to plants and/or soil to have greater activity and/or efficacy as these chemicals prefer soft water and more acidic water.

[0014] The aqueous composition according to the invention may also include an anti foaming agent, which is used to reduce the production of foam or disperse foam after it has formed as a result of mixing the agricultural chemicals with spray water in the spray tank and in its field application. It may also include an organic acid, preferably, tartaric acid, citric acid or combinations thereof, whose function is to reduce the pH of the spray water to the desired level.

[0015] The aqueous composition according to the invention may also be compatible with water-soluble agents such as propylene glycol, which may be used to act as a penetrant and enhance the efficacy of agricultural chemicals.

Detailed description

[0016] Disclosed herein is an aqueous composition for reducing the hardness and/or pH of spray water which is used with agricultural chemicals. The reduction in water hardness and/or water pH will improve the activity and/or efficacy of the agricultural chemicals in that water.

[0017] It has been found that an aqueous composition comprising an effective amount of casein acid dissolved in water and a solubilising amount of one or more ethoxylated cocoamines can be used to reduce water hardness and/or water pH and/or enhance the efficacy of agricultural chemicals.

[0018] Casein acid has previously been used at low levels of between 0.2 to 0.4 %w/w for the purpose of stabilising agricultural chemicals, such as 2,4-dichlorophenoxyacetic acid (2,4-D), 2 methyl-4-chlorophenoxyacetic acid (MCPA) and 3,6-dichloro-2-methoxybenzoic acid (dicamba) aqueous herbicide compositions. At these low concentrations, casein acid does not provide any water hardness or pH reduction properties.

[0019] Casein acid is a water-insoluble protein from milk which has a tendency to clump in an aqueous solution. Accordingly, it usually requires a strong base in order for it to dissolve and be available to reduce water hardness and/or water pH. Strong bases, such as dimethylacetamide and methyl methacrylate, have been used to solubilise and dissolve casein acid in an aqueous solution. However, the solubility of the casein acid in such an aqueous solution is still poor and there are additional difficulties due to the high pH (above pH 12). These difficulties include being highly corrosive, flammable and too volatile to handle, and having phytotoxic effects and compatibility problems with agricultural chemicals that prefer a low pH.

[0020] It has surprisingly been found that one type of surfactant is effective in increasing the water solubility of casein acid and solubilising it into water, namely, ethoxylated cocoamines.

Examples of suitable ethoxylated cocoamines include: coco propyl diamine ethoxylated surfactants (e.g. DS10231 (now called Termix 6010) from Huntsman) and CAS no 61791-14-8 chemicals and their derivatives. While different ethoxylated cocoamines have different properties and may provide different results, it is possible to use them to prepare compositions according to the invention. Examples of ethoxylated cocoamines (all having the same CAS number, i.e. CAS no 61791-14-8) which are suitable for use in the invention include Genamin 050 and Genamin 150 from Clariant, and Toximul* CA 7.5 from Stepan Company. While these ethoxylated cocoamines had different tolerances to being acidified to treat alkaline water while remaining a clear solution, they were all capable of solubilising casein acid into water. In a preferred embodiment, the ethoxylated cocoamines is a coco propyl diamine ethoxylated surfactant.

[0021] Other surfactants, such as tallow amine ethoxylates (e.g. Terwet 3780 from Huntsman, and Hallcomid@ products from Stepan Company), were not found to be suitable for use in this invention.

[0022] The one or more ethoxylated cocoamines enable the composition to comprise casein acid dissolved in water in an effective amount to reduce water hardness and/or water pH. In certain embodiments, the effective amount of casein acid is a concentration of between I to 10 %w/w of the total composition. In one embodiment, the casein acid is present in a concentration of about 5 %w/w of the total composition.

[0023] In certain embodiments, the solubilising amount of the one or more ethoxylated cocoamines is a concentration of between 5 to 75 %w/w of the total composition. In one embodiment, the solubilising amount is between 20 to 55 %w/w of the total composition.

[0024] In certain embodiments of the invention, the composition further comprises an anti foaming agent, which is used to reduce the production of foam or disperse foam after it has formed. Foaming can occur during the mixing of the agricultural chemicals with spray water in the spray tank and in its field application. The anti-foaming agent can stop the creation of foam which can flood out of the spray tank. Examples of anti-foaming agents that are useful in this invention include commercially available silicon anti-foaming agents such as SAG 1572 from MomentiveTM. The Applicant found SAG 1572 to be particularly effective.

[0025] In other embodiments, the composition further comprises an organic acid to assist with reducing water hardness and/or water pH. For example, if the spray water has a very high pH then an organic acid may be used to assist with reducing the pH of the spray water. Examples of suitable organic acids that are useful in this invention include: tartaric acid, citric acid, and dicarboxylic acids such as oxalic acid. In a preferred embodiment, the organic acid is tartaric acid, citric acid or combinations thereof.

[0026] In certain embodiments, the organic acid is present in a concentration of between 2 to %w/w of the total composition. In one embodiment, the organic acid is present in a concentration of about 7.5 %w/w of the total composition.

[0027] It was surprisingly found that the aqueous composition of casein acid and one or more ethoxylated cocoamines remained clear when tartaric acid was added to the composition. This was not the case when surfactants other than ethoxylated cocoamines were used. Further, the Applicant found that when tartaric acid was added at a concentration of 10 %w/w to the aqueous composition according to the invention, the composition was effective in reducing the pH of spray water from pH 9.0 to below 4. In a preferred embodiment, the concentration of tartaric acid is 7.5 %w/w.

[0028] In other embodiments, the composition further comprises a penetration enhancing agent to further enhance the efficacy of agricultural chemicals. The penetration enhancing agent modifies the surface of plants to enable greater penetration of the agricultural chemicals into the plants. In some embodiments of the invention, this composition also contains tartaric acid. Examples of suitable penetration enhancing agents that are useful in this invention include: glycols, silicons and Silwet products from Momentive. In a preferred embodiment, the penetration enhancing agent is water soluble, such as propylene glycol. In certain embodiments, the penetration enhancing agent is present in a concentration of between 5 to 50 %w/w of the total composition. In one embodiment, the penetration enhancing agent is present in a concentration of between 5 to 20 %w/w of the total composition.

[0029] The aqueous composition according to the invention is water-soluble in the spray tank water, which allows for more homogeneous mixing of that aqueous composition in that water and thus increases the efficacy of the composition in treating the water. The aqueous composition of this invention thus provides more consistent reductions in water hardness and/or water pH across the whole spray tank. This results in the agricultural chemicals that are mixed with the spray tank water for administration to plants and/or soil having a greater efficacy.

Examples

[0030] The following examples are given to illustrate the present invention. It should be understood, however, that the invention is not to be limited to the specific conditions or details described in these examples, some of which are preferred embodiments of the invention.

[0031] In the following examples (Examples 1 to 4), the Applicant demonstrated in greenhouse trials that the efficacy of glyphosate, a herbicide, was enhanced when used with spray water which had been treated using the aqueous compositions according to the invention when compared to its use in untreated spray water.

Example 1

[0032] The purpose of this example was to prepare an aqueous composition according to the invention for reducing water hardness. The materials and their concentrations used for this composition were as follows:

Casein acid 5 coco propyl diamine ethoxylated surfactant 50 (DS1231 from Huntsman) Water 45 Total 100

[0033] This aqueous composition was manufactured using the following method:

(a) water and coco propyl diamine ethoxylated surfactant are added to a 250ml glass beaker and mixed and heated to 50°C until a clear solution is formed.

(b) casein acid is added to the above beaker (a) and mixed with the temperature maintained at 50°C until a clear solution is formed.

(c) the above beaker (b) is cooled to 30°C.

Example 2

[0034] The purpose of this example was to prepare an aqueous composition for reducing water hardness and/or water pH. The materials and their concentrations used for this composition were as follows:

Casein acid 5 coco propyl diamine ethoxylated surfactant 40 (DS1231 from Huntsman) Water 45 Tartaric acid 10 Total 100

[0035] The aqueous composition was manufactured using the following method:

(a) 35g of water and coco propyl diamine ethoxylated surfactant are added to a 250ml glass beaker and mixed and heated to 50°C.

(c) the above beaker (b) is cooled to 30°C.

(d) lOg of water and lOg of tartaric acid are added to a separate glass beaker and mixed until a clear solution is formed.

(e) the tartaric acid solution in the above beaker (d) is added to the casein acid and coco propyl diamine ethoxylated surfactant solution in the above beaker (c) and mixed until a clear solution is formed.

Example 3

[0036] The purpose of this example was to prepare an aqueous composition for reducing water hardness and increasing penetration. The materials and their concentrations used for this composition were as follows:

Casein acid 2.5 Coco propyl diamine ethoxylated surfactant 25 (DS1231 from Huntsman) Water 22.5 Propylene Glycol 50 Total 100

[0037] The aqueous composition was manufactured using the following method:

(a) water and coco propyl diamine ethoxylated surfactant are added to a 250ml glass beaker and mixed and heated to 50°C.

(c) the above beaker (b) is cooled to 30°C.

(d) propylene glycol is added to the casein acid and coco propyl diamine ethoxylated surfactant solution in the above beaker (c) and mixed until a clear solution is formed.

Example 4

[0038] The purpose of this example was to prepare an aqueous composition for reducing water hardness, water pH and increasing penetration. The materials and their concentrations used for this composition were as follows:

Casein acid 5 Coco propyl diamine ethoxylated surfactant 25 (DS1231 from Huntsman) Water 42.48 Tartaric Acid 7.5 Propylene Glycol 20 Silicon anti-foaming agent (SAG 1572) 0.02 Total 100

[0039] The aqueous composition was manufactured using the following method:

(c) the above beaker (b) is cooled to 30°C.

(e) 7.5g of water and 7.5g of tartaric acid are added to a separate beaker and mixed until a clear solution is formed.

(f) SAG 1572 is added to the tartaric solution in the above beaker (e) and mixed until a clear solution is formed.

(g) The tartaric acid and SAG 1572 solution in the above beaker (f) is added to the casein acid, coco propyl diamine ethoxylated and propylene glycol solution in the above beaker (d) and mixed until a clear solution is formed.

Example 5

[0040] Greenhouse trials were carried out to investigate the effect of using spray tank water treated with aqueous compositions according to the invention compared with untreated spray tank water.

[0041] For the test formulations, spray tank water (500ppm) was pre-treated with the aqueous compositions including those set out in examples 1 to 3 above. The compositions were used at the rate of 2.5mL per litre of water. A common glyphosate 450g/L, Knockout 450 from Conquest Agrochemicals, was added to the treated spray tank water at 4mL per 1 litre of water and sprayed onto grass by the use of a sprayer. The percentage of grass that was turned into a dead brown colour was measured to indicate the amount of grass killed by the glyphosate. This % brown out was measured by comparing it visually with the untreated control which had 0% brown out.

[0042] For the control formulations, the spray water was not treated with an aqueous composition according to the invention to lower its water hardness and/or water pH. Knockout 450 from Conquest Agrochemicals, glyphosate 450g/L, was added to the untreated water at 4mL per 1 litre of tank water.

[0043] In addition, Knockout 450 from Conquest Agrochemical, glyphosate 450g/L, was added to spray tank water at 4mL per 1 litre of water that was treated with a prior art product LI 700 from Loveland Products, which contains propionic acid and soyal phospholipids as its actives.

[0044] The results of the trials demonstrate that spray water treated with the aqueous compositions according to the invention, from examples 1 to 3 above, increased the efficacy of the glyphosate compared to the untreated spray water or the propionic acid treated spray water. The glyphosate used in spray water treated with the aqueous compositions according to the invention resulted in a greater percentage of grass turned into a brown colour, and thus killed, compared to its use in spray water not treated with an aqueous composition according to the invention.

[0045] The trials also included the use of spray water which had been treated with the aqueous compositions according to the invention, from examples 1 to 3 above, wherein no glyphosate was added to the spray water, which was sprayed onto grass by the use of a sprayer. This resulted in no deleterious phytotoxic effects on the test grass.

[0046] The following tables set out (a) the various aqueous compositions sprayed onto grass; and (b) the results, the percentage of the grass that was turned into a brown colour by the spraying of those aqueous compositions.

(a) Formulation table

Casein acid 3.5 5 5 3.3 2.5 5 5 3 5 Coco propyl 25 N/A N/A 23.5 25 40 50 23 25 diamine ethoxylated surfactant (DS10231) Coco propyl N/A 25 N/A N/A N/A N/A N/A N/A N/A diamine ethoxylated surfactant (Genamin 050) Coco propyl N/A N/A 25 N/A N/A N/A N/A N/A N/A diamine ethoxylated surfactant (Genamin150) Tartaric acid N/A 10 10 N/A N/A 10 N/A N/A 7.5 Propylene Glycol 0 N/A N/A N/A 50 N/A N/A N/A N/A Silwet HS604 N/A N/A N/A N/A N/A N/A N/A 9 10 Silwet stik 2 N/A N/A N/A 6.2 N/A N/A N/A N/A N/A SAG 1572 0.02 N/A N/A 0.02 N/A N/A N/A 0.02 0.02 Water 71.48 60 60 66.98 22.5 45 45 64.98 52.48 Total 100 100 100 100 100 100 100 100 100

Results table

TM172 (spray water treated with example 1 plus glyphosate) 100 TM193S 100 TM174 (spray water treated with example 2 plus glyphosate) 97 TM181 95 TM193 95 TM 180 94 TM175 (spray water treated with example 3 plus glyphosate) 93 TM197 92.5 TM193ST 92.5 Glyphosate in untreated spray water 12.5 L1700 treated spray water with glyphosate 10 TM172 (spray water treated with example 1 with no 2 glyphosate) TM174 (spray water treated with example 2 with no 2 glyphosate) TM175 (spray water treated with example 3 with no 0 glyphosate) Control (untreated spray water with no glyphosate) 0

[0047] The results obtained in this trial show that the treatment of spray water with the aqueous compositions according to the invention improved the activity and efficacy of glyphosate in that water.

Example 6

[0048] This example investigated the in vitro effect of an aqueous composition according to the invention on water samples having different water hardness and pH.

[0049] Hard water at 500ppm (C water) was made up according to CIPAC monograph (Collaborative International Pesticides Analytical Council) and diluted with distilled water to the percentages shown in the 'Water hardness table' below. This water was measured for hardness by the use of test strips. The results are recorded inppm. 1OOmLofCwaterateachofthe percentage of C water in the 'Water hard range table'was combined with 0.25g of an aqueous composition according to the invention. The materials and their concentrations used for this composition according to the invention were as follows:

Casein acid 5 coco propyl diamine 25 ethoxylated surfactant (DS10231) Water 60 Tartaric acid 10 Total 100

[0050] The water hardness of the C water was measured again by the use of test strips after the addition of this aqueous composition according to the invention. The results demonstrate a reduction in water hardness. This was also tested against Melbourne tap water and DI (Deionised water).

(a) Water hardness table

% of Water hvardness arbdns awvkater (ppm)atr02-o

100 428 250 80 360 120 75 250 120 60 200 100 50 200 90 40 200 80 25 120 55 10 75 40 DI 0 25 25 Tap water 50 25

[0051] 1 litre of hard water at 500ppm (C water) was made up and its pH was adjusted with sodium hydroxide to above pH 8.0, which is the typical pH of alkaline borehole water. This C water was divided into five samples of1OOmL of C water. Different amounts of TM184 (see table above) were added to each sample as shown in the "Water pH table" below. Each sample was shaken to mix and the pH of the resulting solution was measured to determine the change in pH. The pH of each solution was measured "neat" or as is with no further dilutions. The results demonstrate greater reductions in water pH when greater amounts of TM184 are used to treat the water.

(b) Water pH table

TMNI184 added to p1 1 a)Cag nP 1(OfnmL of basified C wi ater 500ppm (g) 0 8.02 0 0.08 6.13 1.89 0.1 5.75 2.27 0.23 4.32 3.7 0.32 4 4.02

[0052] The results in the tables above demonstrate that the composition according to the invention reduced hardness in both hard water and alkaline hard water, and reduced the pH of alkaline hard water.

[0053] The word 'comprising' and forms of the word 'comprising' as used in this description and in the claims does not limit the invention claimed to exclude any variants or additions.

[0054] Modifications and improvements to the invention will be readily apparent to those skilled in the art. Such modifications and improvements are intended to be within the scope of this invention.

Claims

The claims defining the invention are as follows:

1 An aqueous composition for reducing water hardness and/or water pH and/or enhancing the efficacy of agricultural chemicals comprising:

(a) an effective amount of casein acid dissolved in water; and

(b) a solubilising amount of one or more ethoxylated cocoamines.
2 The aqueous composition according to the invention wherein the one or more ethoxylated cocoamines is a coco propyl diamaine ethoxylated surfactant.
3 The aqueous composition according to either of claims 1 or 2, wherein the casein acid is present in a concentration of between 1 to 10 %w/w of the total composition.
4 The aqueous composition according to claim 3, wherein the casein acid is present in a concentration of about 5%w/w of the total composition.
The aqueous composition according to any one of claims 1 to 4, wherein the one or more ethoxylated cocamines is present in a concentration of between 5 to 75 %w/w of the total composition.
6 The aqueous composition according to claim 5, wherein the one or more ethoxylated cocoamines is present in a concentration of between 20 to 55 %w/w of the total composition.
7 The aqueous composition according to any one of claims 1 to 6, further comprising an anti-foaming agent.
8 The aqueous composition according to any one of claims 1 to 7, further comprising an organic acid.
9 The aqueous composition according to claim 8, wherein the organic acid is tartaric acid, citric acid or combinations thereof.
The aqueous composition according to either of claims 8 or 9, wherein the organic acid is present in a concentration of between 2 to 15 %w/w of the total composition.
11 The aqueous composition according to claim 10, wherein the organic acid is present in a concentration of about 7.5 %w/w of the total composition.
12 The aqueous composition according to any one of claims I to 10, further comprising a penetration enhancing agent.
13 The aqueous composition according to claim 12, wherein the penetration enhancing agent is propylene glycol.
14 The aqueous composition according to either of claims 12 or 13, wherein the penetration enhancing agent is present in a concentration of between 5 to 50 %w/w of the total composition.
The aqueous composition according to claim 14, wherein the penetration enhancing agent is present in a concentration of between 5 to 20 %w/w of the total composition.
16 A method for treating a body of water to reducing its hardness and/or pH comprising treating the body of water with an aqueous composition according to any one of claims 1 to 15.
17 A method for enhancing the efficacy of an agricultural chemical comprising mixing the agricultural chemical with water which has been treated with an aqueous composition according to any one of claims I to 15.