铝炭微电解处理刚果红废水的效果及脱色机理研究  

Treatment effect and decolorization mechanism of Congo red wastewater by aluminum-carbon microelectrolysis

作　　者：傅强根[1] 胡勇有[1,2] 

机构地区：[1]华南理工大学环境与能源学院,广州510006 [2]工业聚集区污染控制与生态修复教育部重点实验室,广州510006

出　　处：《环境科学学报》2013年第6期1527-1534,共8页Acta Scientiae Circumstantiae

基　　金：国家水体污染控制和治理重大科技专项(No.2009ZX07211-005)~~

摘　　要：采用铝炭微电解法处理刚果红废水,通过批式实验和正交试验考察了主要因素对刚果红脱色及COD去除效果的影响,并采用紫外扫描、离子色谱及LC-MS分析了脱色产物.结果表明,在铝粉投加量为8～24g·L-1范围内,刚果红脱色率及COD去除率均随铝粉投加量的增加而提高,合适的铝粉投加量为16～24g·L-1;刚果红脱色率和COD去除率随着铝炭质量比的减小呈现先增加后降低的趋势,适宜的铝炭质量比为1:3～1:1;初始pH对处理效果影响最大,在pH为10～12.5时,刚果红脱色率及COD去除率随着pH升高而急剧增加;在溶解氧为1.25～7.59mg·L-1的范围内,刚果红脱色率及COD去除率随着溶解氧的升高而降低.最佳条件(铝粉投加量24g·L-1、铝炭质量比1:2、pH=12、反应时间90min)下,刚果红脱色率及COD去除率分别为90.4%和78.6%.刚果红脱色历程为:刚果红分子中的NN双键在新生态[H]的攻击下断裂,生成3,4-二氨基萘-1-磺酸盐和4-氨基3-((4'-氨基-[1,1'-联苯]-4-基)偶氮基)萘-1磺酸盐;后者在[H]的进一步作用下,发生NN双键的断裂,转化为3,4-二氨基萘-1-磺酸盐和联苯胺,萘环开环和C—S键断键,分别生成4-氨基-3-((4'-氨基-[1,1'-联苯]-4-基)偶氮基)-1-磺酸盐和2-((4'-氨基-[1,1'-联苯]-4-基)偶氮基)-1-萘胺.研究表明,铝炭微电解法不能将刚果红完全矿化.Congo red wastewater was treated by aluminum-carbon microelectrolysis,and key factors affecting the decolorization and COD removal were investigated by batch and orthogonal experiments.Decolorization products were determined by UV spectrum,ion chromatography and LC-MS.The results showed that the decolorization and COD removal of Congo red increased with the dosage of aluminum powder in the range of 8-24 g · L^-1,and the appropriate dosages were determined in the range of 16-24 g · L^-1.The decolorization and COD removal of Congo red first increased and then decreased with increase of the Al/C mass ratio and the appropriate ratio was determined as 1：3-1：1.Initial pH was the key factor affecting the treatment process.The decolorization of Congo red was significantly enhanced with increasing pH in the range of 10-12.5.An increase in DO in the range of 1.25-7.59 mg · L^-1 led to decreased decolorization and COD removal of Congo red.Under the optimum conditions（aluminum powder 24 g · L^-1,Al/C mass ratio 1：2,pH=12 and reaction time 90 min）,the decoloration and COD removal of Congo red rose up to 90.4% and 78.6%,respectively.The decolorization pathways of Congo red are proposed as follows：the azo linkage within Congo red molecule is firstly broken down by [H] and two intermediates,3,4-diaminonaphthalene-1-sulfonate and 4-amino-3-（（4＇-amino-[1,1＇-biphenyl]--4-yl）diazenyl） naphthalene-1-sulfonate,are formed;the latter is further transformed to 3,4-diaminonaphthalene-1-sulfonate and benzidine,4-amino-3-（（4＇-amino-[1,1＇-biphenyl]-4-yl）diazenyl）-1-sulfonate and 2-（（4＇-amino-[1,1＇-biphenyl]-4-yl）diazenyl）naphthalen-1-amine are formed due to ring opening of naphthalene and breakdown of C—S linkage.Congo red cannot be mineralized by aluminum-carbon microelectrolysis.

关 键 词：铝炭微电解 刚果红 脱色 

分 类 号：X703.1[环境科学与工程—环境工程] X131.2