Abstract: Research on the removal of 2,4-DCP in aqueous solution by laccase immobilized on chitosan were studied. Factors, such as pH value, temperature and adsorption on support that could influence the oxidation were discussed in detail compared with free laccase. The results indicated that the optimal pH for 2,4-DCP removal by immobilized laccase was around 5.5, lower than the free enzyme for pH 6.0. The optimum temperature of immobilized laccase was between 35℃ and 45℃, wider than the free enzyme. Adsorption of chlorophenol on support had a little effect on the degradation reaction and removal rates of chlorophenols, and the decrease of chlorophenols levels was resulted from catalyzeing for laccase. The continuous oxidation of 2,4-DCP, carried out in the static system of immobilized laccase, showed that the removal efficiency of immobilized laccase still remained over 60% after 6 cycles of operation. Thus the catalytic efficiency of laccase was greatly improved.

Key words: catalytical degradation, removal rates, adsorption, repetition, temperature, pH

摘要： 采用壳聚糖固定化漆酶催化去除水中的2,4－二氯苯酚，探讨了影响反应的不同因素，并与自由漆酶催化反应的条件进行了对比。结果表明，固定酶催化降解反应的最佳pH值在5.5左右，相对于自由漆酶，其最适pH 值向酸性偏移；降解反应的最适温度范围在30～45 ℃之间，较自由漆酶的反应温度范围增大；载体壳聚糖的吸附作用对降解反应和氯酚的去除率影响不大，氯酚的去除主要是漆酶催化氧化反应的结果；连续重复使用固定化漆酶去除模拟废水中的2,4-DCP，在重复操作6次之后，其降解效率仍能保持60%以上。

关键词: 催化氧化, 去除率, 吸附, 重复, 温度, pH值