JPH054357B2 - - Google Patents
Info
- Publication number
- JPH054357B2 JPH054357B2 JP59066377A JP6637784A JPH054357B2 JP H054357 B2 JPH054357 B2 JP H054357B2 JP 59066377 A JP59066377 A JP 59066377A JP 6637784 A JP6637784 A JP 6637784A JP H054357 B2 JPH054357 B2 JP H054357B2
- Authority
- JP
- Japan
- Prior art keywords
- urea
- formaldehyde
- reaction
- nitrogen
- aqueous solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 72
- 239000004202 carbamide Substances 0.000 claims description 30
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 29
- 238000007259 addition reaction Methods 0.000 claims description 16
- 239000007864 aqueous solution Substances 0.000 claims description 13
- 238000006482 condensation reaction Methods 0.000 claims description 11
- 239000000618 nitrogen fertilizer Substances 0.000 claims description 11
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 239000000126 substance Substances 0.000 claims description 8
- 230000002378 acidificating effect Effects 0.000 claims description 5
- 239000007795 chemical reaction product Substances 0.000 claims description 5
- 239000003337 fertilizer Substances 0.000 claims description 5
- 239000011541 reaction mixture Substances 0.000 claims description 5
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 claims description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 32
- 229910052757 nitrogen Inorganic materials 0.000 description 16
- 239000000047 product Substances 0.000 description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 13
- 229910001868 water Inorganic materials 0.000 description 13
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 12
- 238000006243 chemical reaction Methods 0.000 description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 238000000034 method Methods 0.000 description 7
- 238000009833 condensation Methods 0.000 description 6
- 230000005494 condensation Effects 0.000 description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- PNNCWTXUWKENPE-UHFFFAOYSA-N [N].NC(N)=O Chemical compound [N].NC(N)=O PNNCWTXUWKENPE-UHFFFAOYSA-N 0.000 description 4
- 239000002253 acid Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- FERIUCNNQQJTOY-UHFFFAOYSA-N Butyric acid Chemical compound CCCC(O)=O FERIUCNNQQJTOY-UHFFFAOYSA-N 0.000 description 2
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- XBDQKXXYIPTUBI-UHFFFAOYSA-N dimethylselenoniopropionate Natural products CCC(O)=O XBDQKXXYIPTUBI-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- XNGIFLGASWRNHJ-UHFFFAOYSA-N phthalic acid Chemical compound OC(=O)C1=CC=CC=C1C(O)=O XNGIFLGASWRNHJ-UHFFFAOYSA-N 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000007039 two-step reaction Methods 0.000 description 2
- BJEPYKJPYRNKOW-REOHCLBHSA-N (S)-malic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O BJEPYKJPYRNKOW-REOHCLBHSA-N 0.000 description 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- 229920001807 Urea-formaldehyde Polymers 0.000 description 1
- 235000011054 acetic acid Nutrition 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- BJEPYKJPYRNKOW-UHFFFAOYSA-N alpha-hydroxysuccinic acid Natural products OC(=O)C(O)CC(O)=O BJEPYKJPYRNKOW-UHFFFAOYSA-N 0.000 description 1
- 229910021538 borax Inorganic materials 0.000 description 1
- 239000007853 buffer solution Substances 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- 239000006071 cream Substances 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000008098 formaldehyde solution Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 description 1
- 239000000347 magnesium hydroxide Substances 0.000 description 1
- 229910001862 magnesium hydroxide Inorganic materials 0.000 description 1
- 239000001630 malic acid Substances 0.000 description 1
- 235000011090 malic acid Nutrition 0.000 description 1
- DSKJXGYAJJHDOE-UHFFFAOYSA-N methylideneurea Chemical compound NC(=O)N=C DSKJXGYAJJHDOE-UHFFFAOYSA-N 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 235000019260 propionic acid Nutrition 0.000 description 1
- IUVKMZGDUIUOCP-BTNSXGMBSA-N quinbolone Chemical compound O([C@H]1CC[C@H]2[C@H]3[C@@H]([C@]4(C=CC(=O)C=C4CC3)C)CC[C@@]21C)C1=CCCC1 IUVKMZGDUIUOCP-BTNSXGMBSA-N 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 235000010339 sodium tetraborate Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- BSVBQGMMJUBVOD-UHFFFAOYSA-N trisodium borate Chemical compound [Na+].[Na+].[Na+].[O-]B([O-])[O-] BSVBQGMMJUBVOD-UHFFFAOYSA-N 0.000 description 1
- 150000003672 ureas Chemical class 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P60/00—Technologies relating to agriculture, livestock or agroalimentary industries
- Y02P60/20—Reduction of greenhouse gas [GHG] emissions in agriculture, e.g. CO2
- Y02P60/21—Dinitrogen oxide [N2O], e.g. using aquaponics, hydroponics or efficiency measures
Landscapes
- Fertilizers (AREA)
Description
【発明の詳細な説明】
本発明は尿素・ホルムアルデヒド縮合物からな
る緩効性窒素肥料の製造方法に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a slow-release nitrogen fertilizer comprising a urea/formaldehyde condensate.
尿素とホルムアルデヒドとの縮合物からなる緩
効性窒素肥料は、原料となる尿素及びホルムアル
デヒドの入手容易さからその製法が検討されてき
ており、緩効性窒素肥料としては、速効性である
未反応尿素態窒素５％以下、高縮合化しており施
用後も肥効化しない熱水不溶性窒素（Ａ・Ｏ・
Ａ・Ｃ法）６％以下のものが望ましいとされてい
る。 The production method for slow-release nitrogen fertilizer, which is made from a condensate of urea and formaldehyde, has been studied due to the ease of obtaining the raw materials urea and formaldehyde. Hydrothermal insoluble nitrogen (A, O,
A/C method) 6% or less is considered desirable.
従来、この尿素・ホルムアルデヒド縮合物は、
一般的には尿素とホルムアルデヒドとを水酸化ナ
トリウム等のアルカリ金属の水酸化物を用いてPH
８以上の高PH領域で付加反応させた後、付加反応
混合物に硫酸等の鉱酸を添加してPH４以下の低PH
領域で付加反応物を更に縮合又応させる二段反応
を経る方法により製造されている。 Conventionally, this urea/formaldehyde condensate was
Generally, urea and formaldehyde are mixed into PH using an alkali metal hydroxide such as sodium hydroxide.
After conducting an addition reaction in a high pH range of 8 or higher, a mineral acid such as sulfuric acid is added to the addition reaction mixture to achieve a low pH of 4 or lower.
It is produced by a method that involves a two-step reaction in which the addition reactants are further condensed or reacted in a region.
しかし、該二段反応を経て生成する尿素・ホル
ムアルデヒド縮合物は、その製造方法の如何にか
かわらず単一の縮合度をもつた化合物ではなく、
種々の縮合度を持つたメチレン尿素の混合物であ
り、縮合度のコントロールは難しく、従つて未反
応尿素成分が多かつたり、逆に熱水不溶性の高縮
合化物が多く出来てしまい、前記の農業的に望ま
しい成分の緩効性窒素肥料を安定的に製造し得る
方法は確立されていない現状にある。 However, the urea/formaldehyde condensate produced through the two-step reaction is not a compound with a single degree of condensation, regardless of the manufacturing method.
It is a mixture of methylene urea with various degrees of condensation, and it is difficult to control the degree of condensation, resulting in a large amount of unreacted urea components, or conversely, a large amount of highly condensed compounds that are insoluble in hot water. Currently, there is no established method for stably producing slow-release nitrogen fertilizers with desirable components.
発明者等は、上記尿素・ホルムアルデヒド縮合
物製造に係る問題点に鑑み種々検討した結果、特
定比率の尿素とホルムアルデヒドを付加反応した
後、緩やかな反応条件で縮合反応させることによ
つて、上記農業的に好ましい品質の緩効性窒素肥
料が得られることを知得して本発明に到達した。 As a result of various studies in view of the problems associated with the production of urea/formaldehyde condensates, the inventors have discovered that the above-mentioned agricultural products can be produced by carrying out an addition reaction of urea and formaldehyde in a specific ratio, and then carrying out a condensation reaction under mild reaction conditions. The present invention was achieved based on the knowledge that a slow-release nitrogen fertilizer with a quality that is desirable in terms of quality can be obtained.
すなわち、本発明の要旨は、尿素とホルムアル
デヒドとを付加反応させ、次いで付加反応混合物
を縮合反応させて尿素・ホルムアルデヒド縮合物
からなる緩効性窒素肥料を製造する方法におい
て、ホルムアルデヒドと該ホルムアルデヒド１モ
ルに対して１〜２モルの尿素を、PHを８〜10に調
節した水溶液中、40〜80℃の温度条件下で付加反
応させ、得られた付加反応生成物にpKa値（25
℃）が4.5〜5.5の酸性物質を添加してPH4.5〜6.5
の水溶液とし、40〜80℃の温度条件下で縮合反応
させることを特徴とする緩効性窒素肥料の製造方
法に存する。 That is, the gist of the present invention is to provide a method for producing a slow-release nitrogen fertilizer consisting of a urea/formaldehyde condensate by subjecting urea and formaldehyde to an addition reaction and then subjecting the addition reaction mixture to a condensation reaction. 1 to 2 moles of urea is added to the reaction mixture at a temperature of 40 to 80°C in an aqueous solution whose pH is adjusted to 8 to 10, and the resulting addition reaction product has a pKa value (25
℃) is 4.5-5.5 by adding acidic substances to PH4.5-6.5
The present invention relates to a method for producing a slow-release nitrogen fertilizer, which comprises preparing an aqueous solution of the nitrogen fertilizer and carrying out a condensation reaction at a temperature of 40 to 80°C.
以下、本発明を詳細に説明する。 The present invention will be explained in detail below.
本発明で使用する尿素は通常固体尿素を使用す
るが、水溶液でも良く、この場合は高濃度なもの
が好ましい。また、ホルムアルデヒドは、通常水
溶液として例えば市販のホルマリン等を使用し、
その濃度は特に限定されないが、高濃度なものの
方が好ましい。 The urea used in the present invention is usually solid urea, but it may also be an aqueous solution, and in this case, a highly concentrated urea is preferred. In addition, formaldehyde is usually used as an aqueous solution, such as commercially available formalin,
The concentration is not particularly limited, but a high concentration is preferable.
尿素とホルムアルデヒドとを反応に供給する比
率は、ホルムアルデヒド１モルに対し、尿素１〜
２モルの量とし好ましくは約1.5モルとする。該
比率は、製品品質に大きな影響を与え、上記範囲
より尿素が少ないと製品中の高縮合化物が増加
し、尿素が過剰となると残存未反応尿素量が多く
なり望ましい緩効性肥料が得られなくなる。 The ratio of supplying urea and formaldehyde to the reaction is 1 to 1 mol of urea to 1 mole of formaldehyde.
The amount is 2 moles, preferably about 1.5 moles. This ratio has a great effect on product quality; if the urea content is less than the above range, the amount of highly condensed compounds in the product will increase, and if the urea content is excessive, the amount of residual unreacted urea will increase, making it impossible to obtain the desired slow-release fertilizer. It disappears.
このような比率の尿素とホルムアルデヒドは水
溶液で付加させるが、反応速度及び付加反応物の
安定性を考慮してPH８〜10の範囲で反応を行う。
該水溶液のPH調整は一般に使用されるアルカリ性
物質を適宜選択して使用すればよく、たとえばホ
ウ酸ナトリウム、若しくはアルカリ金属又はアル
カリ士類金属の水酸化物である水酸化ナトリウ
ム、水酸化カリウム、水酸化カルシウム、水酸化
マグネシウム等が好適に使用される。アルカリ性
物質は尿素とホルムアルデヒド水溶液を混合後添
加するか、又は、希望のPHになる量をあらかじめ
ホルムアルデヒド水溶液に加えるなど任意の時期
に加えられる。 Urea and formaldehyde in such a ratio are added in an aqueous solution, and the reaction is carried out at a pH of 8 to 10 in consideration of reaction rate and stability of the addition reaction product.
The pH of the aqueous solution can be adjusted by appropriately selecting commonly used alkaline substances, such as sodium borate, alkali metal or alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and water. Calcium oxide, magnesium hydroxide, etc. are preferably used. The alkaline substance can be added at any time, such as after mixing urea and formaldehyde aqueous solution, or by adding an amount that will give the desired pH to the formaldehyde aqueous solution in advance.
尿素とホルムアルデヒドとの付加反応の温度
は、低すぎると反応に長時間かかつて工業的に不
利となり、高すぎると反応速度が速く、製品が高
縮合化してしまうため、40〜80℃で行なう。な
お、該付加反応は、反応液中に実質的にホルムア
ルデヒドが残存しなくなるまで行う。 The addition reaction between urea and formaldehyde is carried out at a temperature of 40 to 80°C, because if the temperature is too low, the reaction will take a long time, which is industrially disadvantageous, and if it is too high, the reaction rate will be fast and the product will be highly condensed. The addition reaction is carried out until substantially no formaldehyde remains in the reaction solution.
本発明は、特に上記のようにして得られた付加
反応生成物を以下のように緩やかな条件で縮合さ
せることを特徴とするものである。 The present invention is particularly characterized in that the addition reaction product obtained as described above is condensed under mild conditions as described below.
すなわち、得られた生成物を通常は反応混合物
としてそのまま分離せずに、酸性物質を添加して
PH4.5〜6.5好ましくは4.5〜5.5に調整する。PHは
縮合反応を生起させるために上記のように酸性と
するが、上記範囲よりPH値を低下させると反応が
速くなり、高縮合化物が増加する。なお、PHの調
節に使用する酸性物質は縮合反応の進行に伴つた
PH変化が生じがたく、かつ目的とする品質の製品
が安定して得られるように、25℃における酸の解
離定数pKaが4.5〜5.5の酸を使用する。この酸は
pKaが条件を満たすものであればいずれでも使用
し得るが、特にクエン酸、リンゴ酸，フタル酸，
酪酸，酒石酸，プロピオン酸，酢酸等の有機酸が
好適である。 That is, the resulting product is usually not separated as a reaction mixture, but an acidic substance is added to it.
Adjust the pH to 4.5-6.5, preferably 4.5-5.5. The pH is made acidic as described above in order to cause the condensation reaction, but when the pH value is lowered from the above range, the reaction becomes faster and the amount of highly condensed compounds increases. In addition, the acidic substance used to adjust the pH changes as the condensation reaction progresses.
An acid with an acid dissociation constant pKa of 4.5 to 5.5 at 25°C is used so that PH changes are difficult to occur and a product of the desired quality can be stably obtained. This acid is
Any pKa can be used as long as it satisfies the conditions, but especially citric acid, malic acid, phthalic acid,
Organic acids such as butyric acid, tartaric acid, propionic acid, acetic acid, etc. are suitable.
縮合反応は反応速度及び縮合化度を考慮して40
〜80℃で行う。また、反応時間は目的とする縮合
度の尿素・ホルムアルデヒド縮合物を得るよう適
宜設定する。 The condensation reaction is 40% considering the reaction rate and degree of condensation.
Perform at ~80°C. Further, the reaction time is appropriately set so as to obtain a urea/formaldehyde condensate having a desired degree of condensation.
得られる縮合反応物は、クリーム状又は、スラ
リー状であるが、これを通常の種々の方法で乾燥
し製品である緩効性窒素肥料とする。この際、乾
燥温度は130℃以下が望ましい。また、製造され
た緩効性窒素肥料を用い化成肥料を製造する際
は、乾燥品を用いても良いが、乾燥前のものを用
いて化成肥料化してもよい。 The resulting condensation reaction product is in the form of a cream or slurry, which is dried by various conventional methods to produce a slow-release nitrogen fertilizer product. At this time, the drying temperature is preferably 130°C or lower. Furthermore, when producing a chemical fertilizer using the produced slow-release nitrogen fertilizer, a dried product may be used, or a chemical fertilizer may be produced using a product before drying.
本発明方法は、以上の特定反応条件により、特
に縮合反応を従来法よりも緩やかな条件で行うこ
とにより、従来困難とされていた尿素・ホルムア
ルデヒド縮合物の縮合度制御が容易に行え、かつ
緩効性窒素肥料として好適な尿素・ホルムアルデ
ヒド縮合物を提供できるので工業的に優れたもの
である。 The method of the present invention makes it possible to easily control the degree of condensation of urea/formaldehyde condensates, which has been difficult in the past, by performing the condensation reaction under the above specific reaction conditions, and in particular under milder conditions than in conventional methods. It is industrially excellent because it can provide a urea/formaldehyde condensate suitable as an effective nitrogen fertilizer.
以下、本発明を実施例により更に詳細に説明す
る。 Hereinafter, the present invention will be explained in more detail with reference to Examples.
実施例 １
尿素135ｇと濃度37重量％のホルムアルデヒド
水溶液122ｇを混合撹拌し、温度50℃の湯浴中に
置いた。Example 1 135 g of urea and 122 g of an aqueous formaldehyde solution having a concentration of 37% by weight were mixed and stirred, and the mixture was placed in a water bath at a temperature of 50°C.
１％水酸化ナトリウム水溶液を添加してPHを10
に調整し、30分間付加反応させた。付加反応後、
湯浴中で引き続いて、50％クエン酸水溶液添加に
よりPHを５に調整し、１時間縮合反応させた後、
80℃で乾燥し、製品を得た。 Adjust the pH to 10 by adding 1% sodium hydroxide aqueous solution.
The addition reaction was carried out for 30 minutes. After the addition reaction,
Subsequently, in a hot water bath, the pH was adjusted to 5 by adding a 50% citric acid aqueous solution, and the condensation reaction was carried out for 1 hour.
A product was obtained by drying at 80°C.
得られた製品の全窒素，尿素態窒素，熱水不溶
性窒素（A.O.A.C法：100℃，PH7.5の緩衝液に不
溶性な窒素）、及び冷水不溶性窒素（A.O.A.C
法：25±２℃の水に水溶性な窒素）を測定した。
その結果は以下の通りであつた。 Total nitrogen, urea nitrogen, hot water insoluble nitrogen (AOAC method: nitrogen insoluble in buffer solution of 100℃, PH7.5), and cold water insoluble nitrogen (AOAC method) of the obtained product
Method: Nitrogen soluble in water at 25±2°C was measured.
The results were as follows.
全 窒素 37.8％
尿素態窒素 4.1％
熱水不溶性窒素 4.3％
冷水溶性窒素 16.7％
比較例 １
実施例１に於いて縮合反応をPH５とする代りに
50％クエン酸溶液によりPH3.5とする以外は、実
施例１と同様に行つて製品を得た。Total nitrogen 37.8% Urea nitrogen 4.1% Hot water insoluble nitrogen 4.3% Cold water soluble nitrogen 16.7% Comparative example 1 Instead of setting the condensation reaction to PH5 in Example 1.
A product was obtained in the same manner as in Example 1, except that the pH was adjusted to 3.5 with a 50% citric acid solution.
その結果は以下の通りであつた。 The results were as follows.
全 窒 素 38.5％
尿素態窒素 3.0％
熱水不溶性窒素 13.1％
冷水不溶性窒素 26.0％
比較例 ２
実施例１に於いて、付加反応後50％クエン酸水
溶液を添加する代りに、5.6％硫酸を添加してPH
５とする以外は、実施例１と同様に行つて、製品
を得た。Total nitrogen 38.5% Urea nitrogen 3.0% Hot water insoluble nitrogen 13.1% Cold water insoluble nitrogen 26.0% Comparative example 2 In Example 1, 5.6% sulfuric acid was added instead of adding 50% citric acid aqueous solution after the addition reaction. and PH
A product was obtained in the same manner as in Example 1, except that Example 5 was used.
その結果は以下の通りであつた。 The results were as follows.
全 窒 素 38.7％ 尿素態窒素 6.1％ 熱水不溶性窒素 2.9％ 冷水不溶性窒素 10.6％Total nitrogen 38.7% Urea nitrogen 6.1% Hot water insoluble nitrogen 2.9% Cold water insoluble nitrogen 10.6%
Claims (1)
いで付加反応混合物を、縮合反応させて尿素・ホ
ルムアルデヒド縮合物からなる緩効性窒素肥料を
製造する方法において、ホルムアルデヒドと該ホ
ルムアルデヒド１モルに対して１〜２モルの尿素
を、PHを８〜10に調節した水溶液中、40〜80℃の
温度条件下で付加反応させ、得られた付加反応生
成物にpKa値（25℃）が4.5〜5.5の酸性物質を添
加してPH4.5〜6.5の水溶液とし、40〜80℃の温度
条件下で縮合反応させることを特徴とする緩効性
窒素肥料の製造方法。1. In a method for producing a slow-release nitrogen fertilizer consisting of a urea/formaldehyde condensate by causing an addition reaction between urea and formaldehyde, and then condensing the addition reaction mixture, the amount of formaldehyde and 1 to 2 mol per 1 mol of the formaldehyde is of urea in an aqueous solution with a pH adjusted to 8 to 10 at a temperature of 40 to 80°C, and an acidic substance with a pKa value (25°C) of 4.5 to 5.5 is added to the resulting addition reaction product. 1. A method for producing a slow-release nitrogen fertilizer, which comprises adding the fertilizer to form an aqueous solution with a pH of 4.5 to 6.5, and carrying out a condensation reaction at a temperature of 40 to 80°C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59066377A JPS60210585A (en) | 1984-04-03 | 1984-04-03 | Manufacture of slow release nitrogen fertilizer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59066377A JPS60210585A (en) | 1984-04-03 | 1984-04-03 | Manufacture of slow release nitrogen fertilizer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60210585A JPS60210585A (en) | 1985-10-23 |
| JPH054357B2 true JPH054357B2 (en) | 1993-01-19 |
Family
ID=13314072
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59066377A Granted JPS60210585A (en) | 1984-04-03 | 1984-04-03 | Manufacture of slow release nitrogen fertilizer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60210585A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01286985A (en) * | 1988-05-11 | 1989-11-17 | Mitsui Toatsu Chem Inc | Production of slow-release nitrogen fertilizer |
| JPH0764667B2 (en) * | 1992-09-30 | 1995-07-12 | 朝日工業株式会社 | Method for producing slow-acting granular organic fertilizer |
-
1984
- 1984-04-03 JP JP59066377A patent/JPS60210585A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60210585A (en) | 1985-10-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0290103A3 (en) | Triazone fertilizer and method of making | |
| CA2238474A1 (en) | Melamine polymetaphosphate and process for its production | |
| US2544649A (en) | Caustic alkali composition of matter and its use as a polyvalent metal precipitationinhibitor | |
| US2822358A (en) | Modified sulfite waste liquor and process for its preparation | |
| JPH09508428A (en) | Production of polyaspartic acid from maleic acid and ammonia | |
| US4381368A (en) | Process for the preparation of urea-formaldehyde resins | |
| JPH054357B2 (en) | ||
| US2700047A (en) | Aqueous hydrolysis of flavanone glycosides | |
| US4120685A (en) | Process for the preparation of urea-formaldehyde condensates to be used as fertilizers | |
| JPH11510135A (en) | How to produce fertilizer | |
| US4895983A (en) | Process for producing methylol urea solution and process for producing slow-releasing nitrogenous fertilizer using the same | |
| JPS627922B2 (en) | ||
| US4169952A (en) | Process for the preparation of cyclohexanone-2-carboxamide | |
| US4454103A (en) | High acid monocalcium phosphate and process for preparing the same | |
| USRE23584E (en) | Manufacture of pentaerythritol | |
| JPH0474310B2 (en) | ||
| US3190742A (en) | Process for producing a slow-acting and quick-acting nitrogenous fertilizer mixture containing crotylidenediurea | |
| US5756839A (en) | Process for preparing D,L-aspartic acid from ammonium salts of the maleic acid | |
| JPS60264384A (en) | Manufacture of slow release nitrogen fertilizer | |
| SU1231046A1 (en) | Method of producing complex fertilizer | |
| JPS63129088A (en) | Manufacture of slow-release nitrogen fertilizer | |
| US3190741A (en) | Process for producing a slow-acting nitrogenous fertilizer mixture containing crotylidenediurea | |
| JPH04273844A (en) | Preparation of 2,2'-oxydisuccinic acid salt | |
| US4429131A (en) | Process for the production of 3,5-dialkylpyridines | |
| SU1692975A1 (en) | Method for obtaining complex fertilizer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |