JP4805677B2 - Process for the production of glycine-concentrated sodium chloride crystals with improved flowability - Google Patents

Description

TECHNICAL FIELD The present invention relates to a simple, economical and efficient circulation method for producing rhombohedral dodecahedral glycine concentrate, free-flowing salt from salt water.

Background and Prior Art Attention in crystallization and the various ways of changing the shape and structure of crystals have a long history because the very wide range of physical and chemical properties of crystalline solid materials This is because it is determined by the crystal form and size. Efforts that have been made to change the crystallization method to produce new crystalline forms of materials continue for many important materials for various reasons. Reasons include, for example, improvement of mass handling characteristics of particulate substances, production of substances that are stronger or more durable than existing substances, production of substances having improved physical properties such as optical chirality, and long-term storage period. Production of substances having better flow characteristics.

  Conventional methods for changing the shape (ie “feature”) or crystal lattice (ie “morphology”) of crystalline materials are; (1) using additives (Weissbuch et al., Science 253: 637, 1991; Addadi et al. , Topics in Stereochem. 16: 1, 1986; Addadi et al., Angew. Chem. Int. Ed. Engl. 24: 466, 1985; and Addadi et al., Nature 296: 21; 1982); (2) crystallization Examples include changing the crystallization solvent used to dissolve the solute (such as crystallization from the gas phase); (3) changing the supersaturation of the crystallization solute; and (4) changing the rate of evaporation.

  Salt is the basic raw material for the production of various industrial chemicals, except sodium carbonate (soda ash), sodium hydroxide (caustic soda), and chlorine, except those that are essentially dietary ingredients. . In addition, salt is used in the textile, dairy, dyeing, food, fertilizer, paper and pharmaceutical industries. The caking of water-soluble inorganic salts such as salt is a common problem in storage. It is believed that caking occurs within such salts because of the formation of a solid internal crystalline bridge that solidifies the crystals together. Evaporating the minimum amount of water on the surface of the crystal leads to the formation of internal crystal bridges and the resulting sticking over long storage periods. Of course, caking reduces free flow, directly negatively affects the use of salt as a dietary ingredient, and increases storage problems. In addition to the formation of salt bridges, the shape of the crystal particles directly affects the flow properties of the material. The larger internal crystal surface area is in contact and has a negative effect on the flow properties because it is in the form of a cube. Obviously, the inner crystal surface contact area is much less in the case of a spherical or nearly spherical crystalline, thereby improving its fluidity.

  In the prior art (R. Kern, 1953, Compt. Rend., 23b, 830), supersaturation has been shown to have a defined effect on changing the crystal properties of the salt. At high supersaturation, salt crystals grow as octahedral ((111) face centered) shape crystals instead of their normal cubic ((100) face centered) shape. However, these conditions are very extreme in practical use in the production of crystals with salt changes and cannot be used.

  In the prior art, urea has been known since 1783 to change salt crystals from trihedral to dodecahedron (J. B. L. Rome de I'lsle 1783, Crystallographie, 2nd edition Paris).

  In the prior art (UK Patent No. 752,582 by N. V. Koninklijke Nederlandsche Zoutindustre, 1954) it is claimed that a small amount (4 ppm by weight) of potassium ferrocyanide very well prevents salt caking. A plausible explanation for the effectiveness of potassium ferrocyanide as an anti-caking agent is that the habit modifiers form intra-crystalline caking bridges that become dendritic and therefore brittle. It has found application in cases where salt must be dispersed over a wide range, such as winter deicing applications, but cannot be used as a dietary ingredient due to the potential toxicity of cyanide.

  In the prior art (L. Phoenix, British Chemical Engineering, Vol-11, 1966, 34), a long list of various faux modifiers and their effectiveness as anti-caking agents are reported. This list includes cyanide salts of various metal ions, cadmium chloride, lead chloride, potassium silico-tongue skin, ammonia triacetamide, victamide and the like. These agents, at low concentrations, change the habit of the NaCl crystalline form derived from the cube (100) to the dendritic (100) and octahedral (111) forms. However, none of these additives are used in NaCl as a food because of the toxicity and other practical issues of the additive.

  Conventional Technology (Scrutton, A. New Sci. Group, Imp. Chem. Ind. PLC, Runcorn, UK. Symposium Papers-Institution of Chemical Engineers, North Western Branch (1985), (3, Cryst. Habit), 3.1-3.13 .), It has been shown that NaOH can also act as a habit modifier for NaCl in an evaporative crystallizer, resulting in octahedral (111) shaped NaCl crystals. Clearly, both crystallization techniques (ie, evaporative crystallization) and the disintegrating nature of the NaOH habit modifier suggest no possibility of developing a method to produce NaCl crystals with modifications for dietary applications. do not do.

  In the prior art (Sasaki, Shigeko; Yokota, Masaaki; Kubota, Noriaki. Iwate Univ., Morioka, Japan. Nippon Kaisui Gakkaishi (2001), 55 (5), 340-342.), The crystal is adjusted to pH 2.72. It is described that an octahedral {111} face of NaCl crystal appeared in the presence of citric acid. A new surface was never confirmed at the natural pH of citric acid (= 0.75). However, although citric acid has good health care properties, the disadvantages of this method are the need for pH adjustment and the acquisition of only octahedral crystals, compared to the dodecahedron crystals of the present invention. It is not spherical in nature.

  In the prior art (Fenimore, Charles P .; Thrailkill, Arthun. J. Am. Chem. Soc. 1949, 71, 2714), glycine, pyridine, betaine, and β-alanine in an aqueous NaCl solution grow NaCl crystals. It is described that a change is made to the habit; first it results in the formation of a rhomboid dodecahedron and the other gives an octahedron. The main drawback of this prior art is that the required initial concentration of glycine is as high as 10% in saturated brine even if rhombus dodecahedrons are obtained with glycine. Furthermore, in the course of the crystallization process, the glycine concentration continues to increase and large amounts of glycine can precipitate with the salt after reaching the saturation limit of glycine. This makes the process uneconomical and salt unacceptable. The prior art does not point out this weakness and does not describe any solution. Theoretical considerations (A. Julg and B. Deprick, J. Cryst. Growth., 1993, 62, 587; B. Deprick-Cote, J. Langlet, J. Caillet, J. Berges, E. Kassab and R. Constanciel, Theor. Chim. Acta., 1992, 82, 435) shows that the amphoteric form of glycine is absorbed on the (110) face of NaCl, thereby growing this face more slowly than the (100) face, This suggests the formation of rhombohedral dodecahedron crystals. Glycine is more attractive as a habit modifier because it helps the growth of the (110) face to produce rhomboid dodecahedron (ie, nearly spherical) shaped NaCl crystals.

  According to the Ullmann Encyclopedia (2002), glycine is reported to be refreshing, sweet, and abundant in muscle and shrimp. It is considered to be an important flavor component of these products. When used as an additive in vinegar, pickles, and mayonnaise, it reduces acidity and makes sweetness their fragrance. In the prior art [Pillsbury Comp., US3510310, 1970 and C. Colburn, Am. Soft Drink J. 126 (1971)], it has also been reported that glycine exhibits a special antiseptic effect [AG Castellani, Appl. Microbiol. 1 (1953) 195.Nisshin Flour Milling, JP 7319945, 1973 (G.Ogawa, K. Taguchi); Chem. Abstr. 81 (1974) 76689z. Nippon Kayaku, JP-Kokai81109580, 1981; chem. Abstr. 95 (1981 ) 202313b]. The above prior art not only clearly shows that glycine is not harmful, but it shows that it can actually have an advantageous effect on a given food. In the context of the present invention, such foods will contain salt and contain 0.5-1.0% glycine as an additive.

  The object of the present invention is to develop a simple, economical and effective circulation method for producing rhombus dodecahedral glycine concentrate, free-flowing salt from salt water.

  Yet another object of the present invention is to develop a process in which brine can be used from all possible sources.

  Yet another object of the present invention is to develop a process in which drying is performed at room temperature in order to be cost effective.

  Yet another object of the present invention is to develop a process in which most of the glycine crystallized together can be removed from the salt by washing with saturated brine.

  Still another object of the present invention is to solve the problem of the use of glycine as a salt crystallizing modifier as revealed in the prior art, and to use the glycine as a modifier for the almost spherical ( Rhombus dodecahedron) is to provide a practical method for producing crystals.

  Another object is to show that glycine can be dissolved in artificial and natural salt water to the required amount and can produce the desired habit changes during salt production using sunlight.

  Another object of the present invention is best done when the crystal habit modification is best done when the salt water temperature during evaporation is below 40 ° C., which is ideally suited for salt production using solar radiation. It is to show that.

  Yet another object is to consider a simple method for removing excess glycine which is crystallized with the salt during the evaporation process.

  Another objective is to show that the habit-changing properties of glycine are maintained in an actual saline system containing other dissolved salts.

  Another object is to use saturated brine to wash salt crystals that have been modified to dissolve glycine in saturated brine without loss of salt.

  Another object is to use saturated brine as described in 5 above, for washing salt that has been modified in a manner such that it obtains saturated brine with the required concentration of glycine for direct reuse. Is to adjust the amount.

  Another object is to show that there is no change in the crystalline form of the salt while washing the salt with altered habits with saturated brine as described in 5 above.

  Another object is to show that the obtained salt has excellent flow properties when compared to salts produced under similar conditions without the use of glycine.

  Yet another object is to provide 0.5-1.0% glycine in a salt with a modified habit, where glycine has an advantageous effect as a micronutrient, fragrance or preservative. It has been reported.

  Another object is to produce a salt-modified salt from glycine-containing saturated saline obtained after washing the salt-modified salt.

  Another objective is to eliminate glycine loss except to the extent desired to obtain a glycine fortified salt in order to make the method useful in practice.

SUMMARY OF THE INVENTION The present invention relates to a simple, economical and efficient circulation method for producing rhombohedral dodecahedral glycine concentrate, free-flowing salt from salt water, the method comprising about 10-25% A range of concentrations of glycine is added to saturated brine, the saturated brine containing glycine is evaporated, and crystals with a high content of glycine are obtained with the mother liquor, and the crystals are washed with saturated brine to 0 Obtaining rhombohedral dodecahedron-shaped glycine concentrated salt having a high glycine content in the range of 5 to 1.0% and washed salt water, obtaining salt water produced by combining the mother liquor with the washed salt water, Entrust salt water to evaporation by sunlight and repeat steps (iii) to (v) to obtain rhombohedral dodecahedron glycine concentrated salt from salt water with glycine concentration ranging from 0.5 to 1.0% To do Comprising.

DETAILED DESCRIPTION OF THE INVENTION The present invention therefore relates to a simple, economical and efficient circulation method for producing rhombohedral dodecahedral glycine concentrate, free-flowing salt from salt water, the method comprising 10-25 % Glycine is added to saturated brine, the saturated brine containing the glycine is evaporated, crystals with a high content of glycine are obtained with the mother liquor, and the crystals are washed with saturated brine Obtaining a rhombohedral dodecahedron-shaped glycine concentrated salt having a glycine content in the range of 0.5 to 1.0% and a washed salt water, obtaining a salt water produced by combining the mother liquor with the washed salt water, and The generated salt water is left to evaporate with sunlight, and the steps of (iii) to (v) are repeated, and the rhombohedral dodecahedron-shaped glycine concentrated salt is from salt water with a glycine concentration in the range of 0.5 to 1.0%. Acquisition Comprising.

In one embodiment of the present invention, a simple, economical and efficient circulation method for producing rhombohedral dodecahedral glycine concentrate, free-flowing salt from salt water, the method includes:
Add glycine at a concentration in the range of about 10-25% to saturated brine,
Evaporating the saturated brine containing glycine to obtain crystals with a high content of glycine with mother liquor,
Washing the crystals with saturated brine to obtain a rhombohedral dodecahedral glycine concentrated salt having a glycine content in the range of 0.5-1.0% and the washed brine,
・ Acquire salt water produced by combining the mother liquor with the washed salt water,
-Entrust the produced salt water to evaporation by sunlight, and-Repeat steps (iii) to (v) to obtain rhombohedral dodecahedron-shaped glycine-concentrated salt from salt water with a glycine concentration of 0.5-1.0%. Earn with a range,
Comprising steps.

  In still other embodiments of the present invention, the brine is selected from the group comprising synthetic brine, natural brine, such as sea brine, subsoil brine, and lake brine.

  In yet another embodiment of the invention, the evaporation is carried out at a temperature in the range of 20-40 ° C. and more preferably by evaporation with sunlight under ambient conditions.

  In yet another embodiment of the invention, the initial concentration of glycine in saturated brine is maintained in the range of 22-25% (w / v).

  In yet another embodiment of the invention, glycine crystallized together is removed primarily from the salt by washing with saturated brine.

  In yet another embodiment of the invention, the volume of saturated brine used for washing is such that the glycine content of the brine is 22-25% after washing.

  In yet another embodiment of the present invention, the washed product is subjected to evaporation by direct sunlight to produce salt once again with a habit modification, or combined with mother liquor remaining after salt preparation to produce sunlight. It can be left to evaporation.

  In yet another embodiment of the invention, washing the salt with saturated brine has no detrimental effect on the morphology of the salt with altered habit.

  In yet another embodiment of the present invention, the salt modified salt has improved flow properties because of its substantially spherical shape.

  In yet another embodiment of the invention, the salt with a modified habit is less prone to bond to the surface of the plastic.

  In yet another embodiment of the present invention, the glycine utilization efficiency is in the range of 95-100%.

  In yet another embodiment of the present invention, the glycine in the salt can serve as a perfume, preservative and micronutrient as reported in the prior art for the properties of glycine.

  In yet another embodiment of the present invention, a method is reported for producing an increased amount of glycine salt that performs the additional function of glycine being a habit modifier and produces substantially spherical crystals with improved flow characteristics. ing. Glycine is recycled in the process of the present invention for utility. The present invention is applicable for salt production from synthetic and natural salt water and is particularly suitable for salt production by sunlight.

  The present invention relates to a method for recycling glycine in a method for producing nearly spherical crystals of NaCl rich in glycine micronutrients. The method of the present invention is commercially available under ambient conditions in the presence of glycine (crystallizing modifier) to produce rhomboid dodecahedron crystals with excellent free-flowing properties instead of the normal cubic shape. Handles recrystallization of salt crystals. The glycine habit modifier is continuously reused and maintains 0.5-1.0% (w / v) glycine in the salt that serves as a micronutrient. This method may be applied to pure saline solutions or even applicable to natural saline systems such as sea brines and subsoil brines.

  The present invention does not report the obvious problem in using the crystal habit-changing properties of glycine, i.e., the need for high concentrations of glycine to change the effective hull and the prior art. Efforts will be made to eliminate the problem of high concentrations of glycine in the crystallized salt that was revealed during the process. Methods such as reported in the prior art are actually very effective in terms of the use of glycine at high levels and also in the amount of glycine in the salt that has been altered in the habit which can affect the flavor and compatibility of the salt. It is reported from too many viewpoints. The main inventive step of the present invention is: realization that a substantial amount of glycine is lost during the evaporation phase, (ii) using glycine from saturated salt water with a modified habit crystal Embodiment of the ability to maintain the desired form of the salt crystals without any loss of salt, (iii) the salt water obtained after washing the salt contains the desired amount of glycine and thus by sunlight The salt directly altered by evaporation can be obtained without the need for any further glycine. Further inventiveness comes from two advantages derived from the use of glycine as an additive in salt water: a crystal habit with altered free-flow properties and a salt because the salt is almost spherical. It is the occurrence of potential use as a perfume, preservative and micronutrient.

  In one embodiment of the present invention, the brine used for the production of the salt with altered habit is a synthetic brine obtained by dissolving the salt or a brine of natural origin, such as sea brine, subsoil brine and It can be synthesized either by dissolving the lake brine.

  In another embodiment of the invention, glycine is added to saturated brine at a concentration of 22-25% (w / v) to ensure a dodecahedron form of the salt crystals from the beginning of crystallization.

  In another embodiment of the invention, the brine temperature was maintained below 40 ° C. and evaporation was performed under ambient conditions.

  In another embodiment of the invention, the volume of saturated brine used is in the range of 100-500 ml and the brine is evaporated to an original volume of 10-20%.

  In yet another embodiment of the present invention, the mother liquor is decanted and the crystallized salt is washed with fresh saturated brine containing no glycine.

  In yet another embodiment of the present invention, the volume of saturated brine used for washing is such that the glycine content during washing is 22-25% (w) of the original 22% after addition of the mother liquor from salt crystallization during washing. / V).

  In yet another embodiment of the present invention, the salt maintains its altered form after washing with fresh saturated brine.

  In yet another embodiment of the invention, the salt with a modified habit is clearly more free flowing than the salt produced without glycine during the crystallization process under essentially the same conditions. is there.

  In yet another embodiment of the invention, the glycine residue in the salt ranges from 0.5 to 1.0% w / w.

  In yet another embodiment of the present invention, the glycine utilization efficiency is 95-100%.

  The following examples are given by way of illustration and are not constructed to limit the scope of the invention.

Example 1
Excess commercially available NaCl was added to 150 ml distilled water and the mixture was stirred at room temperature for 0.5 hour. The solid / liquid mixture was then filtered and 100 ml of such filtered brine was maintained in an open breaker under ambient conditions in the laboratory for crystallization. After 90% evaporation, the resulting crystals are harvested by filtration and dried in a fluid bed dryer. Microscopic observation confirmed that the crystals were in cubic form.

Example 2
Saturated brine was prepared as in Example 1 above. 10 g of commercially available glycine was added to 100 ml brine and stirred at room temperature. The resulting solution containing 10% (w / v) glycine in saturated brine was evaporated under the same conditions as in Example 1 above, and the crystals were isolated by filtration and dried in a fluid bed dryer. Acquired crystals were mainly in cubic and octahedral forms.

Example 3
The experiment of Example 2 was repeated with 15% instead of an initial glycine concentration of 10%, and the NaCl crystals were predominantly octahedral in shape. Some glycine crystals were also confirmed.

Example 4
The experiment of Example 2 is repeated by 25% instead of 10% initial glycine concentrations, crystallization of NaCl was mainly dodecahedron shape. It has been discovered that significant amounts of glycine crystals are also co-crystallized with NaCl. The flow characteristics of the salt crystals are qualitative compared to the salt of Example 1 above, and the former was found to be clearly more free flowing. This salt also had very little tendency to adhere to the surface of the plastic container in which it was stored.

Example 5
The experiment of Example 4 was repeated except that the evaporation was performed at 50 ° C. instead of ambient conditions. The resulting salt crystals were found to have a shape similar to that of the cubic form and that described in Example 1. Glycine crystals were also present in the salt.

Example 6
The crystals obtained in Example 4 were washed with 90 ml of saturated brine prepared in Example 1 above. After washing, the resulting crystals were isolated and dried as described in Example 1. Observation of such crystals revealed that the salt crystals maintained the rhombohedral dodecahedron form, but most of the glycine crystals disappeared. IR analysis of the salt using a quantitative assay technique showed that its glycine content was 0.83% (w / w).

Example 7
The mother liquor obtained in Example 4 was combined with the wash from Example 6 and left to evaporate under ambient conditions. The crystals were then harvested and dried. The salt crystals were rhombohedral dodecahedron and contained a significant amount of glycine crystals in the same manner as the salt described in Example 4. It was discovered that the process of recycling the mother liquor and wash was repeated 7 times, and each time the salt crystals were rhomboid dodecahedron with 0.5-1.0 glycine content.

Example 8
The experiment of Example 4 was repeated with 500 ml of subsoil brine instead of pure brine. The specific gravity of the salt water was 1.208 kg / L. Brine was evaporated to a specific gravity of 1.239 kg / L. The crystals from which the salt was formed were rhombohedral dodecahedron shapes with a significant amount of co-crystallized glycine crystals. It was discovered that the salt was washed with fresh 1.208 kg / L subsoil and maintained in crystalline form while the glycine crystals were largely lost.

The main advantages of the present invention are:
1. A method for producing a glycine concentrated salt having improved flow properties because of the nearly spherical nature of the crystals,
2. Use of acceptable additives as crystal habit modifiers,
3. The versatility of the method, which has no detrimental effects on crystal habit modification, resulting in improved flow properties, with as many impurities as natural salt water,
4). Applicability to the production of salt by evaporation from sunlight,
5. Almost quantitative reuse of glycine for practicality,
It is.

Claims (11)

A simple, economical and efficient circulation method for producing rhombohedral dodecahedral glycine concentrate, free-flowing salt from salt water, the method comprising:
(i) adding a concentration of glycine in the range of 10-25% (w / v) to saturated brine;
(ii) evaporating saturated brine containing glycine to obtain crystals with a high content of glycine, with mother liquor,
(iii) washing the crystals with saturated brine to obtain a rhombohedral dodecahedral glycine concentrated salt having a glycine content in the range of 0.5-1.0% (w / v) and washed saturated brine,
(iv) the mother liquor won generating saturated brine in combination with saturated brine and the washed,
(v) entrust the generated saturated brine to evaporation by solar radiation, and
(vi) Repeat steps (iii)-(v) to obtain rhombohedral dodecahedral glycine concentrated salt from saturated brine with a glycine concentration in the range of 0.5-1.0% (w / v).
A method comprising steps. The method of claim 1, wherein the saturated brine is selected from the group consisting of synthetic brine and natural brine.   The method according to claim 1, wherein the evaporation is performed in a range of 20 to 40 ° C.   The method of claim 1, wherein the initial concentration of glycine in saturated brine is maintained in the range of 22-25% (w / v).   The method of claim 1, wherein the co-crystallized glycine can be largely removed from the salt by washing with saturated brine. The method according to claim 1, wherein the volume of saturated brine used for washing is selected so that the glycine content of the saturated brine is 22-25% (w / v) after washing. The washed saturated salt water is directly subjected to evaporation by sunlight, and once the salt is prepared, the salt having a changed shape is produced once again or combined with a residual mother liquor, and then subjected to evaporation by sunlight. the method of.   2. Washing the salt with saturated brine does not have the detrimental effect of not being able to maintain the modified salt form after washing with respect to the modified salt form. the method of.   The method of claim 1, wherein the salt having a modified shape has improved flow characteristics due to being substantially spherical. The method of claim 1, wherein the glycine recycling efficiency is in the range of 95-100%.   The method of claim 1, wherein glycine in the salt can act as a flavor, preservative and micronutrient.