双季铵盐杀生剂的中试合成及现场应用

Pilot scale production and application of biquaternary ammonium salt

在小试的基础上,以工业级十二烷基二甲基叔胺和环氧氯丙烷为原料,于50 L反应釜中合成了一种对称型阳离子双十二烷基γ-双季铵盐杀生剂(DBAS),收率高达96.08%,~1H NMR图谱表明其分子中含有—N^+(CH_3)_2—和—OH等基团,与小试产物结构相同。以山东某焦化厂的循环冷却水为对象,DBAS为杀生剂进行现场试用。结果表明,向保有水量为900 m^3的循环冷却水系统中投加10 L 5.7%DBAS溶液,2.5 h内杀菌率即达96.08%,加药2 d后,杀菌率仍为93.64%,较原氧化性杀生剂有较大抑菌性能提升。DBAS对循环水系统中异养菌具有明显抑制作用,其投加量与浊度变化关系呈正相关关系,据此确立以其为指示的杀生机制及投加周期,即每3~5 d投加1次,每次投加5 L浓度为5.7%的DBAS。为期一个月的现场试用,其循环水浊度均低于6NTU,远低于该公司要求≤20NTU的考核指标。双季铵盐杀生剂DBAS具有杀菌见效快、药效持续时间长、菌体易从循环水系统中分离等优点,适用于工业循环冷却水中微生物控制,是一种较理想的新一代工业用杀生剂,有一定的市场应用前景和推广价值。

Didodecyl γ-biquaternary ammonium salt（ DBAS） was synthesized from industrial di-methyldodecylamine and epoxy chloropropane in pilot scale. The yield was up to 96. 08%.1H NMR spectra showed that it has the groups which were the same as laboratory production,such as——N＋（ CH3）2—,—OH,and so on. The DBAS synthesized in pilot scale were applied in the circulating cooling water of a coking plant in Shandong. The results show that DBAS has an obvious inhibitory effect on heterotrophic bacteria in circulating cooling water system,when 10 L DBAS（ 5. 7%） was added to circulating cooling water which has a capacity volume of 900 m3,the sterilization efficiency can be up to 96. 08% in 2. 5 h,and the efficiency can remain 93. 64% in 2 d,it has larger antibacterial performance improvement compared with the original oxidizing biocide. DBAS has an obvious inhibitory effect on heterotrophic bacteria in circulating water system,the relation between dosage and turbidity were positively correlated,so 5 L 5. 7% DBAS was added into the circulating cooling water system every 3 d,the water quality indicators can meet the plant＇s inspection standard（ ≤20NTU） during the almost-one-month trial（ below 6NTU）. DBAS has a quick efficacy which can last for a long time,and it can make bacteria separate from circulating water easily,so it can be widely used to kill heterotrophic bacteria in industrial circulatingcooling water system,it＇s a new ideal industrial biocide,and it has certain market application prospect and promotional value.