JPH01219184A - Production of cupric oxide powder - Google Patents
Production of cupric oxide powderInfo
- Publication number
- JPH01219184A JPH01219184A JP63042101A JP4210188A JPH01219184A JP H01219184 A JPH01219184 A JP H01219184A JP 63042101 A JP63042101 A JP 63042101A JP 4210188 A JP4210188 A JP 4210188A JP H01219184 A JPH01219184 A JP H01219184A
- Authority
- JP
- Japan
- Prior art keywords
- cupric oxide
- oxide powder
- temperature
- electrolytic
- electrolyte
- 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.)
- Pending
Links
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 title claims abstract description 115
- 239000000843 powder Substances 0.000 title claims abstract description 50
- 229960004643 cupric oxide Drugs 0.000 title claims abstract description 43
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 239000003792 electrolyte Substances 0.000 claims abstract description 27
- 239000010949 copper Substances 0.000 claims abstract description 20
- 238000005868 electrolysis reaction Methods 0.000 claims abstract description 19
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052802 copper Inorganic materials 0.000 claims abstract description 13
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims abstract description 5
- 239000011734 sodium Substances 0.000 claims abstract description 5
- 239000008151 electrolyte solution Substances 0.000 claims description 12
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 6
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 3
- 229910017604 nitric acid Inorganic materials 0.000 claims description 3
- 229910052708 sodium Inorganic materials 0.000 claims description 3
- XAEFZNCEHLXOMS-UHFFFAOYSA-M potassium benzoate Chemical compound [K+].[O-]C(=O)C1=CC=CC=C1 XAEFZNCEHLXOMS-UHFFFAOYSA-M 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 abstract description 6
- 229910052938 sodium sulfate Inorganic materials 0.000 abstract description 4
- 235000011152 sodium sulphate Nutrition 0.000 abstract description 4
- OTYBMLCTZGSZBG-UHFFFAOYSA-L potassium sulfate Chemical compound [K+].[K+].[O-]S([O-])(=O)=O OTYBMLCTZGSZBG-UHFFFAOYSA-L 0.000 abstract description 3
- 229910052939 potassium sulfate Inorganic materials 0.000 abstract description 3
- 235000011151 potassium sulphates Nutrition 0.000 abstract description 3
- 150000003839 salts Chemical class 0.000 abstract description 3
- 229910002651 NO3 Inorganic materials 0.000 abstract 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 abstract 2
- 238000004062 sedimentation Methods 0.000 description 15
- 239000007788 liquid Substances 0.000 description 12
- 239000000463 material Substances 0.000 description 10
- 238000000926 separation method Methods 0.000 description 9
- 238000001914 filtration Methods 0.000 description 7
- JJLJMEJHUUYSSY-UHFFFAOYSA-L Copper hydroxide Chemical group [OH-].[OH-].[Cu+2] JJLJMEJHUUYSSY-UHFFFAOYSA-L 0.000 description 6
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 6
- 239000006228 supernatant Substances 0.000 description 6
- AEJIMXVJZFYIHN-UHFFFAOYSA-N copper;dihydrate Chemical compound O.O.[Cu] AEJIMXVJZFYIHN-UHFFFAOYSA-N 0.000 description 5
- 239000002253 acid Substances 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 238000010908 decantation Methods 0.000 description 4
- 238000000354 decomposition reaction Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- -1 polyethylene Polymers 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 239000004743 Polypropylene Substances 0.000 description 3
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000007664 blowing Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 239000000706 filtrate Substances 0.000 description 3
- 229920001155 polypropylene Polymers 0.000 description 3
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000010406 cathode material Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 239000004744 fabric Substances 0.000 description 2
- 239000003779 heat-resistant material Substances 0.000 description 2
- 238000002161 passivation Methods 0.000 description 2
- VWDWKYIASSYTQR-UHFFFAOYSA-N sodium nitrate Chemical compound [Na+].[O-][N+]([O-])=O VWDWKYIASSYTQR-UHFFFAOYSA-N 0.000 description 2
- 238000000967 suction filtration Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000005750 Copper hydroxide Substances 0.000 description 1
- 241000549556 Nanos Species 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000012611 container material Substances 0.000 description 1
- 229940116318 copper carbonate Drugs 0.000 description 1
- 229910001956 copper hydroxide Inorganic materials 0.000 description 1
- BERDEBHAJNAUOM-UHFFFAOYSA-N copper(I) oxide Inorganic materials [Cu]O[Cu] BERDEBHAJNAUOM-UHFFFAOYSA-N 0.000 description 1
- XTVVROIMIGLXTD-UHFFFAOYSA-N copper(II) nitrate Chemical compound [Cu+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O XTVVROIMIGLXTD-UHFFFAOYSA-N 0.000 description 1
- GEZOTWYUIKXWOA-UHFFFAOYSA-L copper;carbonate Chemical compound [Cu+2].[O-]C([O-])=O GEZOTWYUIKXWOA-UHFFFAOYSA-L 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- KRFJLUBVMFXRPN-UHFFFAOYSA-N cuprous oxide Chemical compound [O-2].[Cu+].[Cu+] KRFJLUBVMFXRPN-UHFFFAOYSA-N 0.000 description 1
- 229940112669 cuprous oxide Drugs 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000007922 dissolution test Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000005189 flocculation Methods 0.000 description 1
- 230000016615 flocculation Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000000203 mixture Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 235000010333 potassium nitrate Nutrition 0.000 description 1
- 159000000001 potassium salts Chemical class 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 235000010344 sodium nitrate Nutrition 0.000 description 1
- 239000004317 sodium nitrate Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は、電気銅を陽極とする電解により酸化第二銅粉
末を製造する方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing cupric oxide powder by electrolysis using electrolytic copper as an anode.
［従来の技術］
一般に酸化第二銅粉末は第二銅塩の製造用原料あるいは
触媒として用いられているが、該粉末が黒色を呈してい
るために顔料や塗料の原料としても使用されている。[Prior Art] Cupric oxide powder is generally used as a raw material or catalyst for producing cupric salts, but because the powder has a black color, it is also used as a raw material for pigments and paints. .
上記のような粉末は通常、水酸゛化銅、炭酸銅、硝酸銅
などの加熱分解あるいは銅粉の空気中での加熱により製
造されているが、製造原価を安くし、かつ硫酸等の酸に
溶解した時の未溶解残渣の生成抑制の目的のために電解
で製造する方法も提案されている（特公昭６１−２２０
３４）。The above-mentioned powders are usually manufactured by thermal decomposition of copper hydroxide, copper carbonate, copper nitrate, etc., or by heating copper powder in the air. A method of manufacturing by electrolysis has also been proposed for the purpose of suppressing the formation of undissolved residue when dissolved in
34).
上記に提案された方法は電気銅を陽極として硫酸ナトリ
ウム水溶液を電解する際に、陽極及び陰極をそれぞれ隔
膜袋内に収納し、硫酸ナトリウム水溶液を電解液とし、
電解液ｐＨ５〜１３、電解液温度５５℃〜７５℃および
陰極電流密度１５０〜３００Ａ／ｍ ２において、電解
浴槽中で酸化第二銅粉末を得るというものである。In the method proposed above, when electrolyzing a sodium sulfate aqueous solution using electrolytic copper as an anode, the anode and cathode are each housed in a diaphragm bag, and the sodium sulfate aqueous solution is used as the electrolyte.
Cupric oxide powder is obtained in an electrolytic bath at an electrolyte pH of 5 to 13, an electrolyte temperature of 55 to 75 C, and a cathode current density of 150 to 300 A/m2.
［発明が解決しようとする課題］
しかしながらこの方法によれば、主として電解液温度の
高いことに帰因して電解浴槽中で得られた酸化第二銅粉
末粒子の濾過性が悪く、又デカンテーションにより分離
する場合、沈降不充分で上澄液が褐色になり、沈降分離
による酸化第二銅粉末の収率（歩留）が低下するという
問題がある。[Problems to be Solved by the Invention] However, according to this method, the filterability of the cupric oxide powder particles obtained in the electrolytic bath is poor mainly due to the high temperature of the electrolytic solution, and the decantation is difficult. In the case of separation, there is a problem that the supernatant liquid becomes brown due to insufficient sedimentation, and the yield (yield) of cupric oxide powder due to sedimentation separation decreases.
また、このような電解で得られた酸化第二銅粉末の一部
が電解槽底部に沈積し、長時間滞留すると槽底に固まっ
た状態となり、取り出しに（くなるという欠点があり、
さらに又上記のように電解液温が５５℃〜７５℃と高い
ために電解槽材料として高価な耐熱材料が必要であり、
安価な塩化ビニール材を使用すると劣化し易くなるとい
う経済的に不利な点があることが判った。In addition, a part of the cupric oxide powder obtained by such electrolysis settles at the bottom of the electrolytic tank, and if it stays for a long time, it becomes hardened at the bottom of the tank and becomes difficult to take out.
Furthermore, as mentioned above, since the electrolyte temperature is as high as 55°C to 75°C, expensive heat-resistant materials are required as electrolytic cell materials.
It has been found that the use of inexpensive vinyl chloride material is economically disadvantageous in that it tends to deteriorate easily.
本発明の目的は、上記の課題を解決し、電解法による酸
化第二銅粉末の製造に際し、工業的に連続かつ安定して
製造できるように濾過性及び沈降性の良い酸化第二銅粉
末を得、かつ電解槽に安価な塩化ビニール材が使用でき
る電解条件を提供することにある。The purpose of the present invention is to solve the above-mentioned problems and to produce cupric oxide powder with good filterability and sedimentation properties so that it can be industrially produced continuously and stably when producing cupric oxide powder by electrolytic method. The object of the present invention is to provide electrolytic conditions that allow the use of inexpensive vinyl chloride materials in an electrolytic cell.
［課題を解決するための手段］
本発明は、硫酸または硝酸のナトリウムまたはカリウム
塩の水溶液を用い、電気銅を陽極として電解すること１
庄よる酸化第二粉末の製造方法において、電解液の温度
３０℃以上５５℃未満、ｐＨ１ｓ、５以上１３未満であ
って、第１図に示すように点Ａ（温度３０℃、ｐＨ１３
） 、Ｂ （ｉ度３０℃、ｐＨ９）、Ｃ（温度５５℃、
ｐＨ６，５） 、Ｄ Ｃ温度５５℃、ｐ Ｈ−１３）で
かこまれる範囲（ただし、温度５５℃、ｐＨ１３の線上
は含まず）内の電解液湿度、ｐＨで電解することを特徴
とする酸化第二銅粉末の製造方法を提供するものである
。[Means for Solving the Problems] The present invention involves electrolyzing using an aqueous solution of sodium or potassium salt of sulfuric acid or nitric acid with electrolytic copper as an anode.
In the method for producing the second oxidized powder by Sho, the temperature of the electrolytic solution is 30° C. or more and less than 55° C., the pH is 1 s or more and less than 13, and as shown in FIG.
), B (I degree 30℃, pH 9), C (temperature 55℃,
Oxidation characterized by electrolyzing at an electrolyte humidity and pH within the range encompassed by pH 6.5), DC temperature 55°C, and pH-13) (however, the temperature 55°C and the pH 13 line are not included). A method for producing cupric powder is provided.
［発明の詳細な説明］
次に本発明の理解を容品にするために具体的かつ詳細に
説明する。[Detailed Description of the Invention] Next, the present invention will be explained specifically and in detail in order to make it easier to understand.
酸化第二銅粉末の原料として電気銅を陽極に使用する。Electrolytic copper is used as the raw material for cupric oxide powder for the anode.
陰極材には銅板、チタン板など銅電解に一般に使用され
ている周知の陰極材を使用するが、これについては特に
制限がない。これらの陽極および陰極はポリエチレン、
ポリプロピレン、ポリエステル等の繊維製の細い織目を
有する隔膜袋中に収納するのが好ましい。陽極の隔膜袋
は生成した酸化第二銅粉末中に陽極から発生したスライ
ムが混入したり、電解液中の懸濁物が陽極に付着するの
を防止し、また陰極の隔膜袋は、陰極で発生する水素ガ
スが酸化第二銅粉末との接触により該粉末を還元して亜
酸化銅、金属銅に変換させることを防止する。As the cathode material, a well-known cathode material commonly used in copper electrolysis, such as a copper plate or a titanium plate, is used, but there are no particular restrictions on this material. These anodes and cathodes are made of polyethylene,
Preferably, it is housed in a diaphragm bag made of fibers such as polypropylene, polyester, etc. and having a fine weave. The diaphragm bag on the anode prevents slime generated from the anode from getting mixed into the cupric oxide powder produced, and prevents suspended matter in the electrolyte from adhering to the anode. This prevents the generated hydrogen gas from contacting the cupric oxide powder to reduce the powder and convert it into cuprous oxide and metallic copper.
電解液は硫酸または硝酸のナトリウムまたはカリウム塩
の水溶液のいずれか又は混合して使用することができる
。The electrolyte can be an aqueous solution of sodium or potassium salts of sulfuric acid or nitric acid, or a mixture thereof.
この塩を分子式で示せば、Ｎａ２５Ｏ＊、ＮａＮＯｓ、
Ｋ２ ＳＯ４、ＫＮＯ３となる。これらの電解液中での
濃度は０．３〜１．１モル／交、好ましくは０．５〜０
．７モル／交で使用する。その理由は、０．３モル／交
未満では電解液の液抵抗が増大するため電力損失が大き
くなり、また濃度が１．１モル／ＩＩを超えると粘度が
増大して、酸化第二鋼粉末の沈降性が悪くなり、また必
要に応じて行われる電解液の空気による撹拌の効果も悪
化するからである。The molecular formula of this salt is Na25O*, NaNOs,
K2 SO4, KNO3. The concentration in these electrolytes is 0.3 to 1.1 mol/a, preferably 0.5 to 0.
．． It is used at 7 mol/cross. The reason for this is that when the concentration is less than 0.3 mol/II, the resistance of the electrolyte increases and power loss increases, and when the concentration exceeds 1.1 mol/II, the viscosity increases and the second oxidized steel powder This is because the sedimentation properties of the electrolytic solution deteriorate, and the effect of stirring the electrolytic solution with air, which is performed as necessary, also deteriorates.
電解液の温度及びｐＨはそれぞれ３０℃以上５５℃未満
、ｐＨ６．５以上１３未満であって第１図に示す点Ａ（
温度３０℃、ｐＨ１３） 、Ｂ （温度３０℃、ｐＨ９
）、Ｃ（温度５５℃、ｐＨ６，５） 、Ｄ （温度５５
℃、ｐ Ｈ−１３）でかこまれる範囲（ただし、温度５
５℃、ｐＨ１３の線上は含まず）内とする。The temperature and pH of the electrolytic solution are respectively 30°C or higher and lower than 55°C, and pH 6.5 or higher and lower than 13, respectively, at point A (
Temperature 30°C, pH 13), B (Temperature 30°C, pH 9
), C (temperature 55°C, pH 6.5), D (temperature 55
°C, pH H-13) (however, temperature 5
5°C and pH 13).
これは酸化第二銅粉末を製造する上で極めて重要なこと
である。This is extremely important in producing cupric oxide powder.
すなわち−膜内に電解液中で生成する
Ｃｕ （ＯＨ）２の分解には、ある程度の温度が必要と
されている（化学大辞典では６０〜８０℃の熱水で分解
すると記載されている）が、本発明者等が鋭意検討した
結果、Ｃｕ （ＯＨ）２の分解温度はｐＨと相関があり
、Ｃｕ （ＯＨ） ２は上記第１図に示す点Ａ、Ｂ、Ｃ
，Ｄでかこまれる範囲内では、容易にしかも短時間でＣ
ｕＯに分解することを見出した。In other words, a certain degree of temperature is required to decompose Cu(OH)2 generated in the electrolyte within the membrane (the Encyclopedia of Chemistry states that it is decomposed in hot water at 60 to 80°C). However, as a result of intensive studies by the present inventors, the decomposition temperature of Cu (OH) 2 is correlated with pH, and Cu (OH) 2 is concentrated at points A, B, and C shown in Figure 1 above.
, within the range surrounded by D, C can be easily and quickly
It was found that it decomposes into uO.
この理由としては平衡論的に考えると
Ｃｕ （ＯＨ）２とＣｕＯの自由エネルギーの値はそれ
ぞれ−２６．６１Ｋｃａｌ／＋ａｏｌｃ、 −３０，４
２ｋｃａｌ／ｍｏｌｅでありＣｕＯの方が安定であり、
Ｃｕ （ＯＨ）２は準安定状態にあるものと考えられる
。The reason for this is that from an equilibrium perspective, the free energies of Cu (OH)2 and CuO are -26.61Kcal/+aolc and -30,4 respectively.
2kcal/mole, CuO is more stable,
Cu(OH)2 is considered to be in a metastable state.
従って、当然のことながら温度が高くなるほどＣｕＯに
分解し品くなる。Therefore, as a matter of course, the higher the temperature, the more the CuO decomposes and the quality becomes worse.
一方、Ｃｕ （ＯＨ）２からＣｕＯへの分解がｐＨと関
係があることについては、ＣｕＯの生成反応を＜１）式
のように考えると２５℃での電位とｐＨの関係は、
Ｃｕ＋Ｈ２Ｏ−ＣｕＯ＋２Ｈ” ＋２ｅ’″・（１）Ｅ
−０，５７０−０，０５９１ｐ Ｈ（Ｅ ０−０．５
７０）・（２）（２）式の通りとなる。そして温度が高
くなるほどＥｏは下がり、又直線の傾きが負の方向に大
きくなるため、（１）式の反応の電位が全体的に下がる
ことが、通常考えられる温度より低温及び低ｐＨでもＣ
ｕＯに分解するという実験結果と何らかの対応があるも
のと考えられる。On the other hand, regarding the fact that the decomposition of Cu (OH)2 to CuO is related to pH, if we consider the CuO production reaction as shown in equation <1), the relationship between potential and pH at 25°C is: Cu+H2O-CuO+2H "+2e'"・(1)E
-0,570-0,0591p H(E 0-0.5
70)・(2) It is as shown in equation (2). As the temperature increases, Eo decreases, and the slope of the straight line increases in the negative direction, so the overall potential of the reaction in equation (1) decreases even at a lower temperature and lower pH than is normally considered.
It is thought that there is some correspondence with the experimental result that it decomposes into uO.
次に電解液の温度とｐＨの範囲を限定した理由について
述べる。Next, the reason for limiting the temperature and pH ranges of the electrolytic solution will be described.
添付図面第１図の点Ａと点Ｂを結ぶ直線を直線ＡＢとす
ると、直線ＡＢの左側すなわち温度３０℃未満の場合、
ｐＨが１０以上１３未満であればＣｕ （ＯＨ）２がＣ
ｕＯに変化する領域もわずかに存在するが、得られた酸
化第二銅粉末の濾過性が悪く工業的には実用的ではない
。If the straight line connecting point A and point B in Figure 1 of the attached drawings is straight line AB, then on the left side of straight line AB, that is, when the temperature is less than 30°C,
If the pH is 10 or more and less than 13, Cu (OH)2 becomes C
Although there is a slight region where it changes to uO, the resulting cupric oxide powder has poor filterability and is not industrially practical.
直線ＢＣ上を含まない直線ＢＣの下側では、Ｃｕ （Ｏ
Ｈ）２がＣｕＯに変化する時間が１０〜２０時間を超え
るため工業的に酸化第二銅粉末を製造するのに適してい
ない。Below the straight line BC that does not include the top of the straight line BC, Cu (O
H) The time it takes for 2 to change into CuO exceeds 10 to 20 hours, so it is not suitable for industrially producing cupric oxide powder.
直線ＣＤを含めてその右側すなわち温度５５℃以上の場
合、Ｃｕ （ＯＨ）２からＣｕＯに変化するが、前述し
たように得られた酸化第二銅粉末の濾過性が悪く、又デ
カンテーションにより分離する場合、沈降不充分で上澄
液が褐色になり、沈降分離による酸化第二銅粉末の収率
（歩留）が低下するという問題点の他、電解液温度が高
いために電槽材料として高価な耐熱材料が必要であり、
安価な塩化ビニール材を使用すると劣化し易くなるとい
う経済的に不利な点がある。On the right side of the straight line CD, that is, when the temperature is 55°C or higher, Cu(OH)2 changes to CuO, but as mentioned above, the obtained cupric oxide powder has poor filterability and cannot be separated by decantation. In this case, the supernatant liquid becomes brown due to insufficient sedimentation, which reduces the yield of cupric oxide powder due to sedimentation separation, and the electrolyte temperature is high, making it difficult to use as a battery material. Requires expensive heat-resistant materials;
The use of inexpensive vinyl chloride material has the economical disadvantage of being susceptible to deterioration.
一方、直線ＡＤを含めてその上側すなわちｐＨ１３以上
の場合には、不動態化現象を起し電解が不能となり、酸
化第二銅粉末を得ることができない。On the other hand, if the pH is above the straight line AD, that is, if the pH is above 13, a passivation phenomenon occurs and electrolysis becomes impossible, making it impossible to obtain cupric oxide powder.
このように本発明の特徴は電解液の温度及びｐＨをそれ
ぞれ３０℃以上５５℃未満、６．５以上１３未満で第１
図に示す点ＡＳＢ、Ｃ，Ｄでかこまれた範囲で電解する
ことであるが、沈降性、濾過性、経済性等を考えると、
電解液の温度は３５〜４０℃でｐＨはｌＯ〜１１とする
のが好ましい。As described above, the feature of the present invention is that the temperature and pH of the electrolytic solution are set at 30°C or more and less than 55°C, and 6.5 or more and less than 13, respectively.
Electrolysis should be carried out within the range surrounded by points ASB, C, and D shown in the figure, but considering sedimentation, filtration, economic efficiency, etc.
Preferably, the temperature of the electrolytic solution is 35 to 40°C and the pH is 10 to 11.
陰極電流密度は１５０〜３００Ａ／ｍ２、好ましくは２
００〜３００Ａ／ｕ＋ ”とする。この陰極電流密度を
上げると酸化第二銅粉末の生成速度は増すが、３００Ａ
／ａ ２を超えると陰極における水素ガスの発生が多く
なり、電解液中の酸化第二銅が還元され易くなるので好
ましくない。The cathode current density is 150-300A/m2, preferably 2
00 to 300A/u+''.Increasing this cathode current density increases the production rate of cupric oxide powder, but 300A/u+
If it exceeds /a2, hydrogen gas will be generated in large quantities at the cathode, and cupric oxide in the electrolyte will be easily reduced, which is not preferable.
このようにして電解で得られた酸化第二銅粉末は、公知
の方法で電解槽より抜き出し、濾過、乾燥し製品とする
ことができるが好ましくは以ドのような方法を採用する
ことが望ましい。The cupric oxide powder obtained by electrolysis in this way can be extracted from the electrolytic cell, filtered, and dried to produce a product using a known method, but it is preferable to use the following method. .
すなわち、このような電解で得られた酸化第二銅粉末の
一部が電解槽底部に沈積し、長時間滞留すると槽底に固
まった状態となり、取り出しにくくなるという様な問題
を生じさせないために、電解液中に空気を吹き込む。In other words, in order to prevent problems such as a part of the cupric oxide powder obtained by such electrolysis settling at the bottom of the electrolytic tank and staying there for a long time, it becomes solidified at the bottom of the tank and becomes difficult to take out. , blowing air into the electrolyte.
これによって酸化第二銅の水素還元を防１卜すると共に
、酸化第二銅粉末の電解槽への沈積を防＋Ｌ Ｌ、酸化
第二銅粉末を容易に電解液と共に抜き出すことができる
。This prevents hydrogen reduction of the cupric oxide, prevents the accumulation of the cupric oxide powder in the electrolytic cell, and allows the cupric oxide powder to be easily extracted together with the electrolyte.
このようにして形成された酸化第二銅粉末のフロック（
以下単にフロックと略す）を電解液とともに抜き出して
沈降槽に導き、この沈降槽において酸化第二銅粉末を熟
成、乾燥の工程を経て酸化第二銅粉末を得る。フロック
の抜き出しく電解液とともに）は電解槽の上部あるいは
底部より連続的に又は断続的（バッチ式）に抜き出す、
いずれの方法を採用してもよい。A floc of cupric oxide powder thus formed (
The flocs (hereinafter simply referred to as flocs) are extracted together with the electrolyte and introduced into a settling tank, where the cupric oxide powder is aged and dried to obtain cupric oxide powder. The floc (along with the electrolyte) is extracted continuously or intermittently (batch type) from the top or bottom of the electrolytic cell.
Either method may be adopted.
連続的に抜き出す１つの方法としてオーバーフロー液と
ともにフロックを抜き出す方法を採用することができる
。One method for continuously extracting the fluid is to extract the flocs together with the overflow liquid.
この方法によれば比較的簡単な設備構成とすることがで
き、またこれに上記のような空気吹き込みを採用すると
、この空気吹き込みによる撹拌でフロックが容品に浮上
し、効率的にフロックを沈降槽へ導くことができる。This method allows for a relatively simple equipment configuration, and if the air blowing described above is used, the flocs will float to the container due to the agitation caused by the air blowing, and the flocs will be efficiently settled. It can be guided to the tank.
また上記のフロックを導いた沈降槽の上澄液を電解槽へ
還流させることもできる。Furthermore, the supernatant liquid from the sedimentation tank that has led to the above-mentioned flocs can also be returned to the electrolytic tank.
この上澄液を沈降槽から電解槽へとくり返し循環させる
ことによって、この還流液に含まれるわずかな酸化第二
銅粉末の微粒子を電解時の酸化第二銅粉末生成時の核、
あるいは凝集作用を行わしめ、フロック形成をさらに促
進させるという効果が期待できる。By repeatedly circulating this supernatant liquid from the sedimentation tank to the electrolytic tank, a small amount of fine particles of cupric oxide powder contained in this reflux liquid are converted into nuclei when cupric oxide powder is generated during electrolysis.
Alternatively, it can be expected to have the effect of causing flocculation and further promoting floc formation.
そして又、上記のように電解液の温度を５５℃未満で電
解することができるため、電槽材として安価な塩化ビニ
ール材の使用が可能となった。Furthermore, since electrolysis can be carried out at an electrolytic solution temperature of less than 55° C. as described above, it has become possible to use an inexpensive vinyl chloride material as the container material.
本発明においては、このようにして濾過性と沈降分離性
の良好な酸化第二銅粉末を形成させることができる。In the present invention, cupric oxide powder having good filterability and sedimentation separation properties can be formed in this manner.
又、これによって得られた酸化第二銅粉末の酸未溶解残
泊も１重量９６以下となる。Moreover, the amount of undissolved acid remaining in the cupric oxide powder thus obtained is 1 weight or less.
以上のようにして得られた酸化第二銅粉末は上記に示す
用途のみならず超電導材や無電解鋼めっき等の原料とし
て使用することができる。The cupric oxide powder obtained as described above can be used not only for the above-mentioned purposes but also as a raw material for superconducting materials, electroless steel plating, and the like.
［実施例］ 次に実施例について説明する。[Example] Next, an example will be described.
実施例１
塩化ビニール製の電解槽（容にに：２５Ｆ）にｌＯｃｍ
Ｘ ｌＯｃｇの電気銅陽極及び陰極に銅板を用い、陰極
にポリプロピレン製布袋を掛けて装入し、Ｎ ａ ２
Ｓ ０４ 濃度９０ｇ１５Ｉ（０，６３モル１５１）
（７）電解液１交を入れ、電流密度２５０Ａ／ｄ１１２
で電解液温度を２４℃〜５０℃、ｐＨを７〜１３と変化
させる条件で１５分電解を行った。Example 1 1Ocm in a vinyl chloride electrolytic cell (capacity: 25F)
A copper plate was used as the electrolytic copper anode and cathode of X lOcg, and the cathode was covered with a polypropylene cloth bag and charged.
S 04 concentration 90g 15I (0.63 mol 151)
(7) Add 1 alternating electrolyte, current density 250A/d112
Electrolysis was carried out for 15 minutes under the conditions that the electrolyte temperature was varied from 24° C. to 50° C. and the pH was varied from 7 to 13.
なお、ｐＨ２整にはＮａＯＨ溶液を用いた。Note that a NaOH solution was used to adjust the pH to 2.
その後、生成物を電解液と共にサンプリングし、電解条
件と同じ温度に保持した。The product was then sampled together with the electrolyte and kept at the same temperature as the electrolysis conditions.
Ｃｕ （ＯＨ）２ （緑色）からＣｕＯ（黒色）への
分解に要する時間は生成物がサンプリング後完全に黒色
になるまでの時間とし、ＣｕＯへの分解時間を測定した
。The time required for the decomposition of Cu(OH)2 (green) to CuO (black) was defined as the time required for the product to completely turn black after sampling, and the decomposition time to CuO was measured.
そして、ＣｕＯに分解したものについては、該粉末を濾
過、水洗、乾燥した後Ｘ線回折分析により、Ｃｕ （Ｏ
Ｈ）２のピークがなくなり、ＣｕＯのみのピークを示す
ことを確認した。As for the powder decomposed into CuO, the powder was filtered, washed with water, dried, and then analyzed by X-ray diffraction.
It was confirmed that the peak of H)2 disappeared and only the peak of CuO was shown.
この結果を第１表に示す。The results are shown in Table 1.
又、この結果を図示すると第２図の通りとなる。Moreover, this result is shown in FIG. 2.
累’：ＣｕＯに完全に分解しない
（２〜３日後まで観察）
１１２ ：不動態化現象を起し電解不能１１３．１５分
間の電解中にすてにＣｕＯに分解していたもの
実施例２
塩化ビニール製の電解槽（液量：２５１）ｌ、：ｌＯｃ
ｍＸ ｌｏｃ＋ｇの電気鋼陽極及び陰極に銅板を用い、
各々にポリプロピレン布袋を掛けて装入し、第２表に示
すようにＮａ２５Ｏ＋濃度９０ｇノ交（０，６３モル１
５Ｉ）でｐ Ｈ−１０，５の電解液（電解液量１５Ｉ）
を入れ、電流密度２５０Ａ／ｓ ２で液温を３０℃〜５
３℃と変化させる条件で電解を行った。Cu': Not completely decomposed into CuO (observed until 2 to 3 days later) 112: Passivation phenomenon occurs and electrolysis is impossible 113. Items that have already decomposed into CuO during 15 minutes of electrolysis Example 2 Chloride Vinyl electrolytic cell (liquid volume: 251) l, :lOc
Using a copper plate for the electric steel anode and cathode of mX loc + g,
Each was covered with a polypropylene cloth bag and charged as shown in Table 2.
5I) and pH-10.5 electrolyte (electrolyte amount 15I)
and lower the liquid temperature to 30°C to 5°C at a current density of 250A/s 2.
Electrolysis was performed under varying conditions at 3°C.
電解終了後、沈降槽に沈降した酸化第二銅を電解液と共
に抜き出し、デカンテーション、濾過、乾燥を行い酸化
第二銅粉末を得た。After the electrolysis was completed, the cupric oxide that had settled in the settling tank was extracted together with the electrolytic solution, and subjected to decantation, filtration, and drying to obtain cupric oxide powder.
この結果を第２表に示す。又、比較例として液とを７０
℃及び２５℃とし、他は本発明例と同様の条件で電解槽
中でフロックを形成した場合の結果も第２表に示した。The results are shown in Table 2. In addition, as a comparative example, the liquid was
Table 2 also shows the results when flocs were formed in an electrolytic cell under the same conditions as in the present invention except that the temperature was 25°C and 25°C.
なお、濾過性については前記デカンテーションによる上
澄液を抜き去り、残液を３００１として吸引濾過方式で
時間毎の濾液量を測定したものであるが、分り易いよう
にその結果を第３図に示す。Regarding filterability, the supernatant liquid from the decantation was removed and the remaining liquid was set to 3001, and the amount of filtrate was measured every hour using a suction filtration method.For easy understanding, the results are shown in Figure 3. show.
なお、硫酸カリウム、硝酸ナトリウム、硝酸カリウム塩
の水溶液を用いても同様の結果が得られたので、ここで
は硫酸ナトリウム塩を用いた場合のみを例示することと
した。Note that similar results were obtained using aqueous solutions of potassium sulfate, sodium nitrate, and potassium nitrate salt, so only the case where sodium sulfate salt was used will be exemplified here.
なお得られた酸化第二銅粉末の溶解テストのために、酸
化第二銅粉末台５ｇを２０ｇ１５１ Ｈ２８０４溶液
１５１に入れ、４０℃で２０分撹拌し、溶解性をみた。In order to test the dissolution of the cupric oxide powder obtained, 5 g of the cupric oxide powder was added to 20 g of 151 H2804 solution 151, stirred at 40° C. for 20 minutes, and the solubility was examined.
第２表
崖１ 上澄液が清澄せす、褐色となり、沈降分離性が著
しく悪い。Table 2 Cliff 1 When the supernatant liquid is clarified, it turns brown and the sedimentation separation properties are extremely poor.
＊２ 沈降性が著しく悪い。*2 Sedimentability is extremely poor.
第２表及び第３図の結果から明らかなように、本発明例
１〜４では沈降分離性、濾過性が各温度においていずれ
も良好である。As is clear from the results in Table 2 and FIG. 3, Examples 1 to 4 of the present invention have good sedimentation separation properties and filterability at each temperature.
特に第３図は吸引時間に対する濾過液量を示すものであ
るが、この第３図に示されているように濾過性は３５℃
近傍が最も濾過性が良く、電解液温がこれを境に上昇あ
るいは下降しても濾過性が低下していく現象がみられた
。In particular, Figure 3 shows the amount of filtrate versus suction time, and as shown in Figure 3, the filterability is
A phenomenon was observed in which the filtration performance was the best in the vicinity, and even if the electrolyte temperature rose or decreased beyond this point, the filtration performance decreased.
これに対し比較例においては沈降分離性が悪く、また濾
過性に長時間を要し酸化第二銅粉末の収率が悪いばかり
でなく、作業性にも劣っているのが分る。On the other hand, in the comparative example, the sedimentation separation property was poor, and the filtration property took a long time, resulting in not only a poor yield of cupric oxide powder but also poor workability.
また比較例においては、電解槽中のフロックが密に固ま
り樽からの取出しが円滑にいかないという欠点もあった
。Furthermore, the comparative example had the disadvantage that the flocs in the electrolytic cell were densely packed and could not be taken out smoothly from the barrel.
なお酸による溶解テストでは本発明例及び比較例はいず
れも酸未溶解残渣が１重量９６以下であった。In addition, in the acid dissolution test, both the invention examples and the comparative examples had acid undissolved residues of 1 weight 96 or less.
この例からも明らかなように、本発明は濾過性及び沈降
分離性はいずれも良好であり、かつ酸未溶解残渣率も低
く、著しい技術的な優位性か認められる。As is clear from this example, the present invention has good filtration performance and sedimentation separation performance, and also has a low rate of acid-undissolved residue, which is recognized as a significant technical superiority.
［発明の効果］
以上に示すように本発明による電解液温度及びｐＨを適
正に選択して行う電解法は、酸未溶解残渣が１重−％以
下で濾過性及び沈降分離性の良い酸化第二銅粉末を工業
的に連続かつ安定して製造することができ、また電解槽
材として安価な塩化ビニール材の使用が可能なので、技
術的にも又経済的な而からもその効果は顕著である。[Effects of the Invention] As shown above, the electrolytic method according to the present invention, which is carried out by appropriately selecting the temperature and pH of the electrolytic solution, produces an oxidized solution with an undissolved acid residue of 1% by weight or less and good filtration and sedimentation separation properties. It is possible to industrially produce dicopper powder continuously and stably, and it is possible to use inexpensive vinyl chloride material as the material for the electrolytic cell, so its effects are remarkable from both a technical and economic standpoint. be.
第１図は特許請求の範囲を示す電解液温度とｐＨの関係
を示したグラフである。
第２図は実施例１の結果に基づき、
Ｃｕ （ＯＨ）２がＣｕＯに完全に分解するかどうかを
電解液温度とｐＨとの関係でプロットしたグラフである
。
第３図は酸化第二銅粉末の吸引濾過試験の結果を示すグ
ラフである。
１：電解液温３０℃の吸引時間に対する濾過液量２：同
上３５℃の同上
３：同上５０℃の同上
４：同上５３℃の同上
５：同上７０℃の同上
６：同上２５℃の同上
第１図
２０ ３０ ４０ 父 ω
セ２ 図
２０３：１４０５０ｅＤ
ミＡ度 じＣ，）FIG. 1 is a graph showing the relationship between electrolyte temperature and pH, which indicates the scope of claims. FIG. 2 is a graph plotting whether Cu(OH)2 is completely decomposed into CuO as a function of electrolyte temperature and pH, based on the results of Example 1. FIG. 3 is a graph showing the results of a suction filtration test on cupric oxide powder. 1: Filtrate volume with respect to suction time at electrolyte temperature 30°C 2: Same as above at 35°C 3: Same as above at 50°C 4: Same as above at 53°C 5: Same as above at 70°C 6: Same as above at 25°C 1 figure 20 30 40 father ω
Se2 Figure 203:14050eD MiA degree JiC,)
Claims (1)
を用い、電気銅を陽極として電解することによる酸化第
二銅粉末の製造方法において、電解液の温度３０℃以上
５５℃未満、ｐＨ６．５以上１３未満であって、第１図
に示すように点Ａ（温度３０℃、ｐＨ１３）、Ｂ（温度
３０℃、ｐＨ９）、Ｃ（温度５５℃、ｐＨ６．５）、Ｄ
（温度５５℃、ｐＨ１３）でかこまれる範囲（ただし、
温度５５℃、ｐＨ１３の線上は含まず）内の電解液温度
、ｐＨで電解することを特徴とする酸化第二銅粉末の製
造方法。In a method for producing cupric oxide powder by electrolyzing an aqueous solution of sodium or potassium salt of sulfuric acid or nitric acid with electrolytic copper as an anode, the temperature of the electrolyte is 30°C or higher and lower than 55°C and the pH is 6.5 or higher and lower than 13. As shown in Figure 1, points A (temperature 30°C, pH 13), B (temperature 30°C, pH 9), C (temperature 55°C, pH 6.5), D
(Temperature: 55°C, pH: 13)
A method for producing cupric oxide powder, characterized in that electrolysis is carried out at an electrolytic solution temperature and pH within a temperature range of 55° C. and a pH of 13 (excluding the range above the pH line).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63042101A JPH01219184A (en) | 1988-02-26 | 1988-02-26 | Production of cupric oxide powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63042101A JPH01219184A (en) | 1988-02-26 | 1988-02-26 | Production of cupric oxide powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01219184A true JPH01219184A (en) | 1989-09-01 |
Family
ID=12626594
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63042101A Pending JPH01219184A (en) | 1988-02-26 | 1988-02-26 | Production of cupric oxide powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01219184A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5919336A (en) * | 1993-03-31 | 1999-07-06 | Fujitsu Limited | Apparatus for fabricating semiconductor device and method for fabricating semiconductor device |
| RU2570086C2 (en) * | 2014-04-01 | 2015-12-10 | федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Южно-Российский государственный политехнический университет (НПИ) имени М.И. Платова" | Method of obtaining copper (i) oxide |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01156485A (en) * | 1987-12-14 | 1989-06-20 | Nippon Mining Co Ltd | Production of cupric oxide powder |
-
1988
- 1988-02-26 JP JP63042101A patent/JPH01219184A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01156485A (en) * | 1987-12-14 | 1989-06-20 | Nippon Mining Co Ltd | Production of cupric oxide powder |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5919336A (en) * | 1993-03-31 | 1999-07-06 | Fujitsu Limited | Apparatus for fabricating semiconductor device and method for fabricating semiconductor device |
| US6024045A (en) * | 1993-03-31 | 2000-02-15 | Fujitsu Limited | Apparatus for fabricating semiconductor device and method for fabricating semiconductor device |
| RU2570086C2 (en) * | 2014-04-01 | 2015-12-10 | федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Южно-Российский государственный политехнический университет (НПИ) имени М.И. Платова" | Method of obtaining copper (i) oxide |
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