高校化学工程学报
高校化學工程學報
고교화학공정학보
JOURNAL OF CHEMICAL ENGINEERING OF CHINESE UNIVERSITIES
2014年
1期
177-182
,共6页
导向管喷动流化床电极%电流效率%沉积速率%回收率
導嚮管噴動流化床電極%電流效率%沉積速率%迴收率
도향관분동류화상전겁%전류효솔%침적속솔%회수솔
spouted fluidized bed electrode with a draft tube%current efficiency%deposition rate%recovery ratio
在环隙区截面为46 mm×15.5 mm，喷动区截面为10 mm×15.5 mm的半床形式的矩形导向管喷动流化床电极中，以直径0.45 mm的铜颗粒为阴极颗粒，考察了电解液硫酸浓度、槽电压、流化液流量等因素对浓度为1 g×L-1的稀CuSO4溶液电解过程的影响。研究结果表明，导向管喷动流化床电极可以有效地消除“沟流”和“死区”，避免颗粒结块；增加硫酸浓度，可以提高溶液的电导率，加快铜离子的沉积速率，但硫酸浓度过高会导致析氢加剧，降低电流效率和铜离子沉积速率；增加槽电压虽然可以增加电解初期铜离子的沉积速率，但由于析氢更早更快，铜回收率和电流效率将下降；流化液流量增加，环隙区膨胀率增大，阴极有效面积减小，颗粒相电阻增大，铜离子沉积速率和电流效率都下降。在实验条件范围内较佳的工艺条件是：硫酸浓度0.6 mol×L-1、槽电压2.5 V、流化液流速135 L×h-1，在此条件下电解100 min，铜回收率大于99%，平均电流效率大于36%；电解140 min铜回收率可达99.98％、铜离子浓度可降到0.25 ppm。
在環隙區截麵為46 mm×15.5 mm，噴動區截麵為10 mm×15.5 mm的半床形式的矩形導嚮管噴動流化床電極中，以直徑0.45 mm的銅顆粒為陰極顆粒，攷察瞭電解液硫痠濃度、槽電壓、流化液流量等因素對濃度為1 g×L-1的稀CuSO4溶液電解過程的影響。研究結果錶明，導嚮管噴動流化床電極可以有效地消除“溝流”和“死區”，避免顆粒結塊；增加硫痠濃度，可以提高溶液的電導率，加快銅離子的沉積速率，但硫痠濃度過高會導緻析氫加劇，降低電流效率和銅離子沉積速率；增加槽電壓雖然可以增加電解初期銅離子的沉積速率，但由于析氫更早更快，銅迴收率和電流效率將下降；流化液流量增加，環隙區膨脹率增大，陰極有效麵積減小，顆粒相電阻增大，銅離子沉積速率和電流效率都下降。在實驗條件範圍內較佳的工藝條件是：硫痠濃度0.6 mol×L-1、槽電壓2.5 V、流化液流速135 L×h-1，在此條件下電解100 min，銅迴收率大于99%，平均電流效率大于36%；電解140 min銅迴收率可達99.98％、銅離子濃度可降到0.25 ppm。
재배극구절면위46 mm×15.5 mm，분동구절면위10 mm×15.5 mm적반상형식적구형도향관분동류화상전겁중，이직경0.45 mm적동과립위음겁과립，고찰료전해액류산농도、조전압、류화액류량등인소대농도위1 g×L-1적희CuSO4용액전해과정적영향。연구결과표명，도향관분동류화상전겁가이유효지소제“구류”화“사구”，피면과립결괴；증가류산농도，가이제고용액적전도솔，가쾌동리자적침적속솔，단류산농도과고회도치석경가극，강저전류효솔화동리자침적속솔；증가조전압수연가이증가전해초기동리자적침적속솔，단유우석경경조경쾌，동회수솔화전류효솔장하강；류화액류량증가，배극구팽창솔증대，음겁유효면적감소，과립상전조증대，동리자침적속솔화전류효솔도하강。재실험조건범위내교가적공예조건시：류산농도0.6 mol×L-1、조전압2.5 V、류화액류속135 L×h-1，재차조건하전해100 min，동회수솔대우99%，평균전류효솔대우36%；전해140 min동회수솔가체99.98％、동리자농도가강도0.25 ppm。
The effects of sulfuric acid concentration of electrolyte, cell voltage and fluidizing liquid flow rate on electrolytic process of dilute copper sulfate solution with concentration of about 1 g×L-1 were investigated in a semi-spouted bed electrode with a draft tube in which the annulus section is 46 mm′15.5 mm, the spouted section is 10 mm′15.5 mm, and the copper particles of 0.45 mm diameter were used as the cathode particles. The results show that a spouted fluidized bed electrode with a draft tube can effectively eliminate channels and dead zone, and prevent particle agglomeration. Increasing the sulfuric acid concentration of electrolyte could improve the conductivity of solution and accelerate the copper deposition rate, but if the sulfuric acid concentration is too high, it would cause serious hydrogen evolution and reduce the current efficiency and copper deposition rate. Although increasing the cell voltage could increase the initial deposition rate of copper ions, but due to the hydrogen evolution occurs earlier and faster, the copper recovery ratio and current efficiency would decrease. With the increase of fluidizing liquid flow rate, the expansion ratio of annulus area increases, the effective area of the cathode decreases and the resistance of particle phase increases, so the copper deposition rate and current efficiency decrease. The optimal process conditions are:sulfuric acid concentration 0.6 mol×L-1, cell voltage 2.5V and fluidizing liquid flow rate 135 L×h-1, when the dilute copper sulfate solution is electrolyzed for 100 minutes under above conditions, the copper recovery ratio is greater than 99%, the average current efficiency is greater than 36%; when electrolyzed for 140 minutes, the copper recovery ratio could reach 99.98%, and the concentration of copper ions could be reduced to 0.25 ppm.
