Untitled

Abstract

For the purpose of recovering sodium hyroxide and zinc from waste water from low cyanide zinc plating baths, an electrolytic technique was investigated using cation exchange membrane as diaphragm. Granulated graphite anode used exhibited exellent durability and high efficiency for decomposing cyanide. Continuous operation tests showed that the recovering rates of sodium and zinc ions were 10.2mg/min and 1.4mg/min at diaphragm c. d. of 2A/dm2 (the area of the diaphragm on one side was 0.44dm2). Zinc was found to accumulate in the graphite anode as zinc hydroxide and zincate. The amount of zinc recovered was almost 90%.

アルカリジンケート浴からの亜鉛の電析挙動とその結晶形態に及ぼす有機添加剤の構造の影響

“…電気 Zn めっきは，ジンケート浴 1-6) ，ホウフッ化物浴 7) ， 塩化物浴 [8][9][10][11] ，硫酸塩浴 [12][13][14][15][16] ，ピロリン酸塩浴 17,18) ，シアン 化物浴 19,20) V i e w…”

Effect of Organic Additives on Electrodeposition Behavior of Zn from Zincate Solution Containing Potassium Hydroxide and Its Micro Structure

“…電気 Zn めっきの均一電着性，外観，硬度，耐食性，浴電 圧，電流効率等は，ジンケート浴 1-6) ，ホウフッ化物浴 7) ，塩 化物浴 [8][9][10][11] ，硫酸塩浴 [12][13][14][15][16]) ，ピロリン酸塩浴 17,18) ，シアン化 物浴 19,20) (Fig. 2, Fig.…”

Effect of Organic Additives on Electrodeposition Behavior of Zn from Zincate Solution Containing Potassium Hydroxide and Its Micro Structure

“…The throwing power, appearance, hardness, and corrosion resistance of deposited Zn and the electrolytic voltage and current efficiency for Zn deposition depend on the kind of electrolytic solution, such as zincate, 16) boron fluoride, 7) chloride, 811) sulfate, 1216) pyrophosphate, 17,18) and cyanide. 19,20) Cyanide and zincate solutions are used due to the excellent throwing power of alkalic solutions, but cyanide solutions have an effluent treatment problem. Therefore, the use of alkaline zincate solutions has increased from an environmental viewpoint.…”