偶氮染料刚果红在水中的光催化降解过程

通过研究在间歇悬浮体系中直接偶氮染料刚果红在水中的光催化降解过程 ,确定了最佳降解条件 .同时测定了染料溶液的脱色率、COD去除率和矿化率以考察降解过程中脱色与矿化的关系 .另外 ,对降解过程中溶液 pH值的变化及反应的可能中间体进行分析 ,结果表明 :刚果红染料分子的光催化降解过程分为脱色和矿化两个阶段 .矿化主要发生在脱色结束以后 ,并且伴随着脱色溶液的酸化现象 .脱色过程进行较快 ,完全脱色后形成的中间产物需要较长时间才能被逐步矿化 .

刚果红高效降解菌分离鉴定及降解条件优化

目的:本研究以从长期受到印染废水污染的土样中分离到的一株在厌氧条件下可以高效降解偶氮染料刚果红的细菌为样本,通过形态学观察、生理生化鉴定及16SrDNA序列分析鉴定,该菌为克雷伯氏属菌株,并定名为Klebsiellasp.Y12。通过对菌株Y12菌体浓度和刚果红降解率连续24h的测定。发现:菌株在生长到18h时菌体浓度达到最大值;在第16h时刚果红的降解率达到最大,为78%。这表明降解率与菌体生长基本同步。本研究优化了降解培养基的碳源及氮源。结果:最适于刚果红降解的碳源为葡萄糖,最适投加量为8.0g/L;最适氮源为硫酸铵,最适硫酸铵投加量为5.0g/L。且优化后的降解率达93%,比未优化前提高19%。本研究以刚果红为模式染料,筛选出刚果红降解菌株,这对探讨偶氮染料的有效降解,寻找一种有效的偶氮染料降解方法具有实际意义。

突变灰盖鬼伞过氧化物酶降解刚果红的响应面法优化分析

酶法降解偶氮染料刚果红是一个复杂的过程,受温度、pH、酶量、刚果红浓度和双氧水浓度显著影响。为研究各因素及因素间交互作用对刚果红降解影响,提高刚果红的降解率,分别使用单因素法和响应面分析法对刚果红降解条件进行了优化。单因素实验结果显示灰盖鬼伞过氧化物酶降解刚果红的最适条件为:pH 5.0、32℃、酶量4.98 U、双氧水0.1mmol/L、刚果红20 mg/L,此时刚果红最高降解率为34.84%。然后选双氧水浓度、刚果红浓度和灰盖鬼伞过氧化物酶量作为3个因素,通过中心组合设计实验,用响应面法对刚果红降解进行优化分析,最后得到一个拟合度良好的二次多项方程模型(R2=0.9900)。方差分析结果显示,刚果红浓度和酶量是影响最显著的因素,双氧水与酶以及染料与酶之间的交互作用极显著。响应面分析优化后的反应体系为:双氧水浓度0.15 mmol/L,刚果红浓度为27.21 mg/L,酶为2.0 7 U,在此条件下,刚果红降解率达58.13%。

Biodegradation of Congo Red Azo Dye by Aspergillus spp, Isolated from Dye Contaminated Soils

In the present study, it has been aimed to determine the non target effects of Congo red on soil enzyme activities namely amylase, protease, catalase, glucose oxidase and laccases, following the standard procedures. Further, it is also aimed to decolourize the dye effluents by using immobilized fimgal cultures namely Aspergillus spp. isolated from textile effluents and estimate the percentage of decolourization by dye decolourization assay method. The selected fungi were found efficient and dominant type in dye decolourization with the production of laccase and other enzymes. Except laccase, all the enzymes showed maximum activity at 14 days followed by declining trend at 21 days. Maximum enzyme activity was noticed with Aspergillus niger. 95% of decolourization was found within 4-24 h in sodium alginate immobilized fungal cultures compared to controls. The above results clearly indicate the efficiency of these fungi in selective bioremediation of dye contaminated sites.