微生物絮凝剂絮凝条件的响应曲面法优化

OPTIMIZATION OF FLOCCULATING CONDITIONS OF MICROBIAL FLOCCULANT USING RESPONSE SURFACE METHODOLOGY

筛选出一株絮凝剂产生菌TF10,鉴定为巨大芽孢杆菌(Bacillus megaterium).以高岭土悬浊液为絮凝对象,研究了pH值、絮凝剂用量和不同阳离子对TF10产生的絮凝剂P-TF10絮凝效率的影响.结果表明,P-TF10在偏酸和微碱范围内活性较高;絮凝剂存在最佳用量,不足或过高会导致絮凝率下降;Ca2+和Al3+对絮凝的促进作用明显,而Mg2+和Na+对絮凝无作用.应用响应曲面法对P-TF10的絮凝条件进行了优化,得到最佳条件为:pH=4.7,CaCl2浓度为7.0mmol.l-1,P-TF10的用量为34.6 mg.l-1,该条件下絮凝率可达(95.5±1.0)%.

A bacterium TFIO was found to produce microbial flocculant P-TFIO, and was identified as Bacillus megatherium. The effect of pH, flocculating dosage and various cations on flocculating activity was investigated against kaolin suspensions. The results showed that optimum pH and flocculating dosage exist for the flocculating efficiency. Mg2＋ and Na ＋ had no effect on flocculation, while Ca2＋ and Al3 ＋ enhanced the flocculating activity. The response surface methodology was employed to optimize the floeculation process. The best flocculating efficiency （95.5 ± 1.0） % was obtained with pH 4. 7, CaCl2 dosage of 7.0mmol ·1 - 1 and P-TF10 dosage of 34. 6 mg· 1-1.