利用纳米凝胶酶对染料进行降解研究
发布时间：2018-08-13 20:51
【摘要】：全球水污染愈发严重,发展更好的污水处理技术成为了一项重要研究内容。相比其它方法,使用辣根过氧化酶(HRP)催化双氧水降解有机污染物具有绿色环保的独特优势。天然辣根过氧化酶易受到环境影响而失活,本论文通过对天然辣根过氧化酶在分子层面上进行凝胶包裹,制成纳米凝胶酶,并通过纳米粒度仪和酶标仪等仪器,对凝胶酶粒径大小和热稳定性进行表征;然后选用染料工业中常见的染料作为降解对象(盐酸副品红、靛蓝胭脂红、直接红81、刚果红和偶氮荧光桃红等),利用天然的辣根过氧化酶和纳米凝胶酶对之进行降解研究,对比分析不同染料的最佳降解条件,以及纳米凝胶酶对不同染料的降解效率和规律,最后对酶回收尝试循环使用。本论文首先对辣根过氧化酶(HRP)进行化学修饰,通过与氨基的反应接枝双键到HRP表面,进而与羧酸甜菜碱丙烯酰胺(CBAA)发生自由基聚合反应,成功制备了HRP的纳米凝胶酶,其粒径大小约为78纳米。纳米凝胶酶不但保持了辣根过氧化酶的原有活性,而且在热稳定性上要优于天然的辣根过氧化酶。在所有的降解实验中,纳米凝胶酶的降解效果都要好于辣根过氧化酶;辣根过氧化酶和纳米凝胶酶在较宽的pH值范围、过氧化氢浓度范围和30℃-60℃都具有一定的降解能力。多种染料的对比研究发现,HRP及纳米凝胶酶对含有多氨基染料的降解效果最好,几乎能达到100%,并且纳米凝胶酶的降解效率几乎是辣根过氧化酶的两倍;而对含有磺酸基染料的降解效果较差。在回收实验中,由于降解产物对酶有一定的影响,辣根过氧化酶和纳米凝胶酶在经过一次降解后活性都有不同程度的下降,但总体来说,纳米凝胶酶的活性损失程度较小。在工业染料废水中加入吸附剂是现代污水处理的有效且重要方法之一。壳寡糖(COS)表面有许多氨基,是一种倍受欢迎的吸附剂。本论文探究了壳寡糖作为吸附剂对染料降解的影响。研究表明,加入一定浓度的壳寡糖,对于含有磺酸基的染料来说,有助于提高染料的脱色率,对于含有较多氨基的染料来说,加入壳寡糖会降低染料脱色的速率,但不会影响最后的降解率;壳寡糖的浓度越高,对染料的脱色效果越明显,但是过高浓度会造成一定的浪费,所以1%的壳寡糖是一个比较合适的浓度。由于氧自由基主要集中在纳米凝胶酶内部或表面,为了更好的将染料从溶液中去除,本论文还尝试通过化学反应,将壳寡糖接枝到纳米凝胶酶上;后续的染料降解实验表明,将壳寡糖接枝到纳米凝胶酶上以后,能够有效地增强纳米凝胶酶对染料的降解能力。
[Abstract]:The development of better sewage treatment technology has become an important research content because of the serious water pollution in the world. Compared with other methods, the use of horseradish peroxidase (HRP) to catalyze the degradation of organic pollutants by hydrogen peroxide has the unique advantage of green environmental protection. Natural horseradish peroxidase is easy to be inactivated by environment. In this paper, the natural horseradish peroxidase was encapsulated on the molecular level to make nanogel enzyme. The particle size and thermal stability of the gelatinase were characterized, and then the common dyes in the dye industry were selected as the degradation objects (Para-fuchsin Hydrochloride, Indigo Carmine, Indigo Carmine). Direct red 81, Congo red and azo fluorescent peach red, etc.), the degradation of these dyes was studied by using natural horseradish peroxidase and nanogel enzyme, and the optimum degradation conditions of different dyes were compared and analyzed. The degradation efficiency and regularity of different dyes by nanogel enzyme were also studied. In this paper, the horseradish peroxidase (HRP) was chemically modified, and the HRP nanogel was successfully prepared by grafting the double bonds with amino groups onto the surface of HRP, and then by free radical polymerization with carboxylate betaine acrylamide (CBAA). The particle size is about 78 nm. The nanogel enzyme not only maintains the original activity of horseradish peroxidase, but also has better thermal stability than natural horseradish peroxidase. In all the degradation experiments, the degradation effect of nano-gel enzyme was better than that of horseradish peroxidase, and the degradation ability of horseradish peroxidase and nano-gel enzyme was in a wide pH range, hydrogen peroxide concentration range and 30 鈩，
本文编号：2182152
[Abstract]:The development of better sewage treatment technology has become an important research content because of the serious water pollution in the world. Compared with other methods, the use of horseradish peroxidase (HRP) to catalyze the degradation of organic pollutants by hydrogen peroxide has the unique advantage of green environmental protection. Natural horseradish peroxidase is easy to be inactivated by environment. In this paper, the natural horseradish peroxidase was encapsulated on the molecular level to make nanogel enzyme. The particle size and thermal stability of the gelatinase were characterized, and then the common dyes in the dye industry were selected as the degradation objects (Para-fuchsin Hydrochloride, Indigo Carmine, Indigo Carmine). Direct red 81, Congo red and azo fluorescent peach red, etc.), the degradation of these dyes was studied by using natural horseradish peroxidase and nanogel enzyme, and the optimum degradation conditions of different dyes were compared and analyzed. The degradation efficiency and regularity of different dyes by nanogel enzyme were also studied. In this paper, the horseradish peroxidase (HRP) was chemically modified, and the HRP nanogel was successfully prepared by grafting the double bonds with amino groups onto the surface of HRP, and then by free radical polymerization with carboxylate betaine acrylamide (CBAA). The particle size is about 78 nm. The nanogel enzyme not only maintains the original activity of horseradish peroxidase, but also has better thermal stability than natural horseradish peroxidase. In all the degradation experiments, the degradation effect of nano-gel enzyme was better than that of horseradish peroxidase, and the degradation ability of horseradish peroxidase and nano-gel enzyme was in a wide pH range, hydrogen peroxide concentration range and 30 鈩，
本文编号：2182152
本文链接：https://www.wllwen.com/shengtaihuanjingbaohulunwen/2182152.html
