改性黄铁矿为电子供体的生物反硝化脱氮性能  

Biological denitrification and nitrogen removal performance of modified pyrite as electron donor

作　　者：邵磊 唐玉朝[1] 伍昌年[1] 薛莉娉[1] 王坤[1] 黄显怀[1] SHAO Lei;TANG Yuchao;WU Changnian;XUE Liping;WANG Kun;HUANG Xianhuai(Anhui Provincial Key Laboratory of Environmental Pollution Control and Waste Recycling,Anhui Jianzhu University,Hefei 230601,Anhui,China)

机构地区：[1]安徽建筑大学环境污染控制与废弃物资源化安徽省重点实验室,安徽合肥230601

出　　处：《精细化工》2023年第9期2052-2063,共12页Fine Chemicals

基　　金：国家自然科学基金项目(51978003);安徽省教育厅自然科学重大项目(KJ2019ZD54);安徽省教育厅自然科学一般项目(KJ2019JD10)。

摘　　要：将天然黄铁矿球磨至纳米尺度,与二甲基亚砜混合后经过600℃无氧煅烧2 h得到改性黄铁矿。采用XRD、SEM、N_(2)吸附-脱附、VSM对其进行了表征。探究了不同理化因素对改性黄铁矿生物脱氮性能的影响。结果表明,结晶度高的黄铁矿通过改性转变成结晶度低的磁黄铁矿(Fe_(0.95)S_(1.05))且呈多孔蜂窝状结构,比表面积从0.82 m^(2)/g增加到10.54 m^(2)/g,孔径从7.70 nm增加到22.41 nm,改性黄铁矿的磁化强度为12 emu/g。在改性黄铁矿平均粒径200 nm、投加量500.00 mg/L、温度35℃、pH=7.0的条件下,模拟污水中NO_(3)^(–)-N质量浓度从18.50 mg/L降至0.36 mg/L,反应时间由改性前的4.50 h缩短至0.75 h,NO_(3)^(–)-N去除率由改性前的42.80%提至98.10%,表明改性黄铁矿能够作为电子供体被反硝化微生物高效利用。脱氮动力学分析表明,改性黄铁矿为电子供体的自养反硝化反应动力学符合零级反应特征(R^(2)>0.97)。Natural pyrite was ball-milled to nanoscale,mixed with dimethyl sulfoxide,and then anaerobically calcined at 600℃for 2 h to synthesize modified pyrite.The modified pyrite obtained was then characterized by XRD,SEM,N2 adsorption-desorption and VSM.The effects of different physicochemical factors on the biological denitrification performance of modified pyrite were further investigated.The results showed that the modification reaction transformed the highly crystalline pyrite into low crystallinity pyrrhotite(Fe0.95S1.05)with a porous honeycomb structure,the specific surface area increased from 0.82 m^(2)/g to 10.54 m^(2)/g,pore size increased from 7.70 nm to 22.41 nm and the magnetization intensity increased to 12 emu/g.The NO_(3)^(–)-N mass concentration decreased from 18.50 mg/L to 0.36 mg/L in the simulated wastewater when treated with modified pyrite of average particle size 200 nm and dosage 500.00 mg/L at temperature 35℃and pH=7.0.Meanwhile,the reaction time reduced from 4.50 h before modification to 0.75 h and the NO_(3)^(–)-N removal rate increased from 42.80%before modification to 98.10%,showing that the modified pyrite could be efficiently utilized as electron donor by denitrifying microorganisms.Data from denitrification kinetic analysis demonstrated that the kinetics of the autotrophic denitrification(MNPAD)reaction with modified pyrite as electron donor was consistent with zero-level reaction characteristics(R^(2)>0.97).

关 键 词：黄铁矿 电子供体 改性 反硝化 磁黄铁矿 水处理技术 

分 类 号：X703[环境科学与工程—环境工程]