Mahdizadeh Hakimeh, Nasiri Alireza, Gharaghani Majid Amiri, Yazdanpanah Ghazal
Environmental Health Engineering Research Center, Kerman University of Medical Sciences, Kerman, Iran.
Department of Environmental Health, School of Public Health, Kerman University of Medical Sciences, Kerman, Iran.
MethodsX. 2020 Oct 29;7:101118. doi: 10.1016/j.mex.2020.101118. eCollection 2020.
Azo dyes are the largest group of synthetic organic dyes which containing the linkage C-N[bond, double bond]N-C and used in various industries such as textile industries leather articles, and some foods. Azo dyes are resistant compounds against the biodegradation processes. The purpose of this research was hybrid UV/COP advanced oxidation process using ZnO as a catalyst immobilized on a stone surface for degradation of acid red 18 (AR18) Dye. In the hybrid process using some parameters such as the dye initial concentration, pH, contact time and catalyst concentration, the process efficiency was investigated. In order to the dye removal, the sole ozonation process (SOP), catalytic ozonation process (COP) and photocatalytic process (UV/ZnO) were used. The ZnO nanoparticles were characterized by XRD, SEM and TEM analyses. The maximum dye removal was achieved 97% at the dye initial concentration 25 mg/L, catalyst concentration 3 g/L, contact time 40 min and pH 5. As a real sample, the Yazdbaf textile factory wastewater was selected. After that, the physicochemical quality was evaluated. As well as, in the optimal conditions, the AR18 dye removal efficiency was achieved 65%. The kinetic results demonstrated that the degradation reaction was fitted by -first-order kinetic. The UV/COP hybrid process had high efficiency for removal of resistant dyes from the textile wastewater. Advantages of this technique were as follows:•ZnO nanoparticles were synthesized as catalyst by thermal method and were immobilized on the stones.•pH changes had no significant effect on the removal efficiency.•In the kinetic studies, the decomposition reaction followed -first order kinetic.
偶氮染料是最大的一类合成有机染料，含有C-N=N-C键，用于纺织、皮革制品及某些食品等多种行业。偶氮染料是抗生物降解的化合物。本研究的目的是采用以负载在石头表面的ZnO为催化剂的紫外/催化臭氧化高级氧化工艺来降解酸性红18（AR18）染料。在该复合工艺中，通过改变染料初始浓度、pH值、接触时间和催化剂浓度等参数，考察了工艺效率。为了去除染料，采用了单独臭氧化工艺（SOP）、催化臭氧化工艺（COP）和光催化工艺（UV/ZnO）。通过X射线衍射（XRD）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）分析对ZnO纳米颗粒进行了表征。在染料初始浓度25mg/L、催化剂浓度3g/L、接触时间40min和pH值为5的条件下，实现了97%的最大染料去除率。选取亚兹德巴夫纺织厂废水作为实际样品，之后对其理化性质进行了评估。此外，在最佳条件下，AR18染料去除率达到了65%。动力学结果表明，降解反应符合一级动力学。紫外/催化臭氧化复合工艺对纺织废水中难降解染料的去除具有高效性。该技术的优点如下：
• 通过热法合成ZnO纳米颗粒作为催化剂并负载在石头上。
• pH值变化对去除效率无显著影响。
• 在动力学研究中，分解反应符合一级动力学。
