GB2091711A

GB2091711A - Silicate Fertilisers

Info

Publication number: GB2091711A
Application number: GB8101688A
Authority: GB
Original assignee: LANE WAN SHEEN
Current assignee: LANE WAN SHEEN
Priority date: 1981-01-20
Filing date: 1981-01-20
Publication date: 1982-08-04

Abstract

A fertiliser contains K2SiO3 and other nutrients. The K2SiO3 can be formed by reacting K2CO3 or KOH with a silicate, which may be provided by Mg silicate ores such as waste serpentine ore, dolomite or diatomaceous earth. A fertiliser can be produced by reacting K2SiO3 with MgO or CaO, and an acid such as hydrochloric, sulphuric or nitric acid.

Description

SPECIFICATION Sili-pseudo-sol The present invention is related to a hydrous silicic acid colloid and/or neutral potassium silicate containing fertilizer.

Must and reason for manufacturing hydrous silicic acid colloid containing fertilizer is as follows.

in some countries, diatomaceous earth has been used as fertilizer for years. But the diatomaceous earth, like silicon oxide in soil, tdisintegrates very slowly into hydrous silicic acid colloid. Such conversion must be effected by natural factors, i.e. solar energy, chemical energy and micrological population as well as radiation. The principle conditions for forming such hydrogel and hydrosol are as follows: 1. Due to variation of physical and chemical conditions, the composition thereof so formed is very uncertain. 2. Such conversion can only occur slowly at 200--300C and pH 7-8 and dissolution of silicon oxide in water can be traced at least three weeks later. Therefore, the crop will decrease due to poor replenishment of hydrous silicic acid from soil, particularly in case of planting many times a year.Even in subtropical area, the soil can provide hydrous silicic acid (as the principle nutrient as well as vehicle for transporting and preserving other nutrients) to the plant only after season of winter.

Since hydrous silicic acid plays the important role in nutrition and soil itself can not provide hydrous silicic acid in time, hydrous silicic acid existing in soil is very deficient. No matter how much fertilizers of N, P, K.. are added, the plant will inevitably wither, even die.

For solving the above-mentioned problem, a hydrous silicic acid colloid containing, easily soluble fertilizer has to be manufactured artificially so as to replenish appropriate amount of silicon to plant in time. 3. The silicic acid gel solution is in state of microparticles dispersing in water without quick sedimentation.

The surface energy, which is created between water and the microparticle surrounded with the silicic acid particle, forms the adhesion and adsorption of the silicic acid colloid. By capillarity and osmosis, the silicic acid colloid combining other element is adsorbed by the root and nutrients is replenished. 4. Without silicic acid colloid, the plant can not adsorb all of the nutrients. It is only available by incorporating the nutrients with the silicic acid. (Silicate is the ore which has the best capability to combine the other elements). 5. Since ice point and boiling point as well as osmotic pressure of the solution formed by dissolving hydrous silicic acid and other elements in water vary, such fertilizer can be used in any climate and soil.Furthermore, it is important to point out that the quantity of the water applied must be suitable, otherwise the plant can not get enough nutrient. Due to incapability of silicic acid creation naturally under 1 60C, the plant will die in consequence of failure to absorb the nutrients of the conventional fertilizer.

The silica-rich fertilizer according to the present invention, comprises potassium silicate and one or more of other indispensable nutrients employed in plant nutrition. Potassium silicate can be produced by reacting silicate ore e.g., serpentine or silicon dioxide ore, e.g., diatomaceous earth with potassium carbonate.

It is possible in the above reactions that silica-rich fertilizers may contain magnesium oxide and calcium oxide, as in the case of the reaction between potassium carbonate s magnesium silicate or calcium silicate containing ores, when potassium silicate is not separated from the reaction products.

Such silica-rich fertilizer can be treated with suitable acid to convert magnesium oxide, calcium oxide to the water soluble salts to enhance nutrient concentration.

The basic principle of the present invention will be summarized thereafter. 1. Aside from acting acting as a nutrient and forming an colloid solution, hydrous silicic acid can combine with other elements and renders them be easily absorbed by the plant. 2. Ice point, boiling point and osmotic pressure of the solution formed by incorporation other nutrients in the silicic acid colloid has varied after combination, therefore it can supply enough nutrients in any climate and any type of soil. In addition, water has to be timely supplied. 3. Silicic acid colloid containing fertilizer is also very sensitive to pH value, therefore, a suitable range of pH value must be maintained. Since the effect of fertilizer can be enhanced by incorporating the silicic acid colloid, it should be manufactured artificially for plant nutrition.

It is an object of the present invention to provide a silica-rich fertilizer, in which the silicon compound thereof is water soluble and can be absorbed as the plant nutrient. Another object of the present invention is to provide a silica-rich fertilizer which can be applicable for different types of soil i.e. granular or clayey form in every latitude.

Further object of the present invention is to provide a silica-rich fertilizer. When it is applied to the soil, through the nutrient retaining ability of silica sol developed by the potassium silicate, the leaching of the nutrient ingredient is thus reduced.

The above and additional objects will be more apparent by illustrating the examples accompanied by the following drawings, in which: Fig. 1 is a block diagram illustrating the steps of manufacturing the all fertilizers according to the present invention from serpentine.

A silica-rich fertilizer is prepared by reacting a magnesium silicate ore, e.g. Waste serpentine ore, with potassium carbonate. The principle reaction products, magnesium oxide and potassium silicate are easily separated through their different solubility in water. Potassium silicate obtained from the above procedure is then mixed at any proportion with the other soluble nutrients, such as, urea, potassium chloride etc. depending on the result of soil analysis.

It is more preferable that the principle reaction products magnesium oxide and potassium silicate are used incorporately in silica-rich fertilizer without separation. The silica-rich fertilizer, which contains mainly magnesium oxide and potassium silicate, can be treated with suitable acids before mixing with other indispensable nutrients. The acid is selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid. After treatment, magnesium oxide contained in silica-rich fertilizer will be converted to a water soluble magnesium salts, e.g. magnesium chloride, magnesium nitrate and magnesium sulfate to enhance the nutrient concentration of the fertilizer.

The silica-rich fertilizer, which contains mainly magnesium oxide and potassium silicate, can further be treated with an acid selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid, as well as calcium oxide. The calcium oxide can be obtained from waste material of marble or limestone. After treating with acid as well as calcium oxide, magnesium and calcium element nutrient will be enhanced.

Supplanting potassium carbonate, caustic potash can likely be applied to convert a magnesium silicate ore to potassium silicate.

In another example, a silica-rich fertilizer can be produced by utilizing dolomite and silicon dioxide ore, e.g., diatomaceous earth. The process is the same as aforementioned above. A silica-rich fertilizer is produced by reacting diatomaceous earth with potassium carbonate or caustic potash. The silica-rich fertilizer so obtained can either directly be applied to the soil, or further react with dolomite as well as acid, e.g., hydrochloric acid to enhance the nutrient concentration of fertilizer by rendering calcium oxide and magnesium oxide of dolomite to magnesium chloride and calcium chloride.

The silica-rich fertilizer obtained from the preceding processes, is appropriate for supplying silicon element nutrient to the plant in any latitudinal area, while the conventional silica-containing fertilizer can not, because the disintegration of diatomaceous earth contained in the conventional fertilizer is inhibited under cold climate.

The present silica-rich fertilizer is appropriate for supplying silicon element nutrient to the plant in any kind of soil. Particularly, it has advantages that due to its excellent ability of water retaining, it will not be leached even when applied in desert area.

The proportional ratio of the ingredients of silicic acid colloid containing fertilizer is calculated as the following equation.

Silicic acid colloid containing, easily soluble fertilizer= X*%x(Si02. nH20+R . O+R203)+Y*%x(N, P, K,).

*Values of X and Y of the above equation is determined by the soil quality and the climate.

The main starting materials for producing the silicic acid colloid containing fertilizer are silicic acid, silicates, and carbonates. Only valueless marble, serpentine dolomite and diatomaceous earth are explained thereafter as examples.

As shown in Fig. 1, manufacturing process of the present fertilizer using the serpentine as the starting material is illustrated by the block diagrams.

The advantages of adopting the above-mentioned ores as the starting materials lie in that they contain abundant microelements. The steps of acid treatment in the process can decrease the contents of sulfur and chlorine elements contained in the fertilizer. Excess content of sulfur and chlorine elements will be harmful to the quality of soil.

Although the cost of using diatomaceous earth as starting material is much cheaper, the usages of the remaining starting materials can not be overlooked considering that they contain abundant elements which is important in industry.

During the step of neutralization, the reaction product must be fully stirred to be a mixture.

Because of the co-solubility, the ingredients mixed together dissolve more easily than individual existing. Therefore the present fertilizer is easily soluble.

Since the ferromagnetic elements, e.g. iron, cobalt and nickel are dispensible, they are better separated from the starting materials prior to reaction.

Several chemical equations used in manufacturing the present fertilizer are exemplified as below.

A. Process for manufacturing hydrous silicic acid colloid containing fertilizer.

(alkaline, not suitable)

(suitable) B. Process for manufacturing neutralized potassium silicate containing fertilizer:

(acidic not suitable)

(neutral, suitable) C. Magnesium oxide and potassium silicate, which are produced by treating magnesium silicate ore with strong base, are separated by their different solubility in water. Magnesium oxide so obtained can be used as fireproof material.

The following is the explanation for the block diagram as shown in Fig. 1 depicting the production of hydrous silicic acid colloid containing, easily soluble fertilizer.

1. There are three methods of processing potassium silicate.

a. Moist method: ground raw materials+caustic potash (s.p. 1.45) at 3-5 atm. 8 above 1 500C 6 hours steam heating cooling, filtration under pressure, washing, centrifugal separation of potassium silicate and magnesium oxide.

b. High temperature kiln method: ground raw material+granular caustic potash with water 6 hrs heating at 1000-1 1000C injecting of steam at every two hrs later cooling, grinding, extracting of potassium silicate (the rest is magnesium oxide) c. Moderate temperature kiln method: ground raw material+granular caustic potash with water 8 hrs heating at 810-8500C injecting of steam at every two hrs later cooling, grinding, extracting of potassium silicate, silicic acid colloid containing fertilizer.

2. X, Y, Z, represent the production percentage and is calculated based on average value. It has to be adjusted if necessary. For example, the soil of inland area and of poor quality needs the fertility of greater chlorine content and it is thus to produce higher content thereof for necessary portion.

3. The activating treatment is to maintain the inclusion of water content in silicic acid colloid between 8-1 2%. As silicic acid colloid consists of water, it will not be solidified by surrounding interference and can achieve the capability of absorbing and rapid dissolution. The conversion is:

(colloid) where the neutralization with acid takes place at 600C to form colloid.

4. As neutralization with acid will evolve considerable heat, it is necessary to control the temperature between 600C and 650C. The high or low temperature does effect the water content in silicic acid.

5. The present process is only alkalization and neutralization and therefore is easy to carry out.

6. The used raw materials are from ores, i.e. serpentine, marble, dolomite, diatomaceous earth which have no industrial value. Of these four kinds, we can select one or two which are likely to be beneficial. Direct use of potassium silicate is the most preferable but the separation cost will effect the selling price of fertilizer.

7. The most importance is to find out the precious elements from this industrial production and make development in connection with this. As silicic acid and carbonate ore consist of various elements. The attention is to be made on these for development.

8. When silicic acid colloid containing fertilizer is in form of solid, the water content therof does not effect the distribution of fertilizer. When it is in form of fluid or semifluid, it is suitable for application in proper soil and the water content is necessary to be determined practically.

9. As this fertilizer consists of the mixture of silicic acid colloid and salts, it is easily soluble in water in consequence of the co-solubility thereof.

10. Potassium silicate is further converted into hydrous silicic acid colloid to be employed as plant nutrient and it is soluble in water.

The following is the comparison between silicic acid colloid containing fertilizer A and the conventional fertilizer B.

1. (A): At any temperature under and above 1 60C, it can supply plant nutrient as well as convey them and maintain the fertility. It is durable in cold and dry weather, that is, it is not influenced by temperature.

(B): At temperature under 1 60C, silicon oxide is not easily soluble in water and also does not form colloid. At temp. above 280C, the dissolved content of CO2 decreases and thus effects largely the formation of colloid and damages the plant growth. So it is influenced by temperature.

2. (A): Due to the co-solubility of the mixture, it can dissolve more rapidly and simultaneously to supply plant nutrients in time.

(B): It does not possess the co-solubility and has to rely on the exchange of ion to convert into applicable state. Therefore, it can not dissolve rapidly to supply the nutrient to the plant.

3. (A): The addition of this completely soluble fertilizer makes the plant grow without entirely depending upon the soil and therefore it meets the needs of the plant.

(B): The plant needs (Si, Ca. ..) rely on the supply from soil and supply can not meet their consumption.

4. (A): At the fertilizer colloid forming zone, the colloid can absorb the moisture, the surrounding soil does not effect the fertilizer concentrating center; the fertilizer does not easily latch out and thus maintain the fertility. At any temperature and soil condition, it is effective.

(B): The distribution of the fertilizer in soil is not applicable for the roots, the influence of soil on fertilizer becomes large due to the greater contact surface with soil, and it can easily leach out. Therefore the fertilizer can not be maintained and the content is lost.

5. (A): As it is treated with three strong acids, S and Cl content are thus reduced and cause no formation of Na2S, NaCI to damage the property of soil.

(B): Due to the high content of Cl, it is not practical for area along the coast. The long time application of this will damage the property of soil. NaCI, over 1 50 ppm, will prevent the root growth.

6. (A); It contains six main elements (N, P, K, Si, Ca, Mg) and micronutrients and can stimulate plant growth without depending upon the soil.

(B): It contains only three main elements and the rest essential elements have to rely on the supply from soil for plant growth.

7. (A): Silicic acid colloid can cooperate the other elements to enter into the body for nutrition.

(B): In the absence of hydrous silicic acid colloid, the plant can not utilize the fertility, even when there exist fertilizer.

8. (A): It can be applied artificially to the place centred to the absorbable area of plants.

(B): The fertilizer is dispersing in the soil and can not migrate, thus, being unavailable for the distant plants. Such condition can not be adjusted manually The following tables are listed as reference.

Table 1 (A): Nutrients Supplied by the Conventional Fertilizer Nutrients way of supply Main nutrients N, P, K artificially Minor nutrients Mg, B, Si, Ca, Mn, Cu, Zn, Fe, entirely from soil S,CI SiO2. nH2O Naturally occurred (B): Nutrients Supplied by the Present Invention

Nutrients way of supply Main nutrients N, P, K, Si*, Ca*, Mg* Minor nutrients artificially B, Mn, Zn, Cu, S, Fe, CI, Ni, Cr,Al..

Si02. nH2O *Si, Ca, 8 Mg is the additional main elements according to the present invention. Table 2 Analysis of Composition of an Easily Soluble Silicic Acid Colloid Fertilizer Total containing microelements Al, B, Cr, No. K Si Ca Mg N S Cl Nutrients Co,Cu,Fe,Mn,Ni,Mo,Ti,U,V ...etc.

SSS-C1 17.96 6.50 trace 8.38 5.36 6.13 13.57 57.90 Most abundant, from Ore SSC-C2 14.10 55.39 5.90 6.95 4.00 3.05 10.13 48.71 Most abundant, from Ore SSC-C3 17.13 6.42 6.42 5.51 6.35 7.25 16.08 68.45 Most abundant, from Ore SSC-C4 32.93 11.92 trace trace 3.93 4.50 9.95 63.23 Most abundant, from Ore Nitrophoskas, Products of I.G.Dye Industry Ltd. West Germany No. NH4NO3 (NH4)2HPO4 KCl N.% P.% K.% Cl% microelement Remarks C( ) 15.50 15.50 19.00 30.70 17.56 27.13 24.61 none Three nutrient elements are A( ) 15.00 30.00 15.00 38.09 28.12 17.72 16.07 none first introduced by this Co.

I( ) 17.50 11.00 22.00 28.72 12.27 30.94 28.06 none high Cl content, unsuitable G( ) 15.00 11.00 26.50 23.92 11.20 34.02 30.86 none area along coast;solid H( ) 16.50 16.50 20.00 31.58 17.48 26.72 24.23 none NaCl up to 150 ppm, will effect plant growth.

With the invention heretofore explained, it is to be noted that the foregoing preferred embodiments merely describe the invention rather than limit the scope of the invention. The scope of the invention should be defined by the appending claims.

Claims

1. A silica-rich fertilizer, principally for replenishing silicon element nutrient to the plant, comprising potassium silicate and an other indispensable nutrient employed in plant nutrition.

2. A process for manufacturing silica-rich fertilizer comprising, reacting of a silicate with a potassium compound selected from the group consisting of potassium carbonate and potassium hydroxide to produce a potassium silicate containing product.

3. A process for manufacturing silica-rich fertilizer as claim 2, which further comprises, mixing of the potassium silicate containing product with another indispensable nutrient applied for plant nutrition.

4. A process for manufacturing silica-rich fertilizer as claim 2, the silicate is a alkaline earth metal silicate selected from the group consisting of magnesium silicate and calcium silicate.

5. A process for manufacturing silica-rich fertilizer as claim 4, which further comprises, treating of the potassium silicate containing product with an acrid selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid.

6. A process for manufacturing silica-rich fertilizer comprising, reacting of potassium silicate with an alkaline earth metal oxide selected from the group consisting of magnesium oxide and calcium oxide and an acid selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid.

7. A silica-rich fertilizer as claimed in claim 1 and substantially as hereinbefore described.

8. A process for manufacturing a silica-rich fertiliser substantially as hereinbefore described with reference to the accompanying drawings.

9. A silica-rich fertilizer, principally for replenishing silicon element nutrient to the plant, comprising potassium silicate and an other nutrient employed in plant nutrition.