Fe-Mn/ETS-10催化剂制备及其CO-SCR的脱硝性能
来源期刊:中国有色金属学报2020年第11期
论文作者:付国友 何汉兵 张丽 马英
文章页码:2616 - 2627
关键词:Fe-Mn催化剂;催化脱硝;CO-SCR催化性能;ETS-10分子筛
Key words:Fe-Mn catalyst; catalytic denitrification; CO-SCR catalyst property; ETS-10 Molecular sieve
摘 要:通过高温固相法制备不同负载量的Fe-Mn/ETS-10催化剂,利用X射线衍射仪(XRD)、傅里叶红外仪(IR)、扫描电子显微镜(SEM)、X射线光电子能谱分析(XPS)等对催化剂进行表征,考察了不同负载量对Mn-Fe/ETS-10形貌、结构组成、以及选择性催化还原(SCR)性能的影响。结果表明:Fe-Mn/ETS-10催化剂具有良好的均一性和分散性,并保持ETS-10原有形貌、晶型;5%Fe-1%Mn/ETS-10具有更多的活性位和更高的脱硝性能。CO-SCR催化性能测试结果显示,5%Fe-1%Mn/ETS-10在脱硝温度300 ℃和400 ℃时脱硝率分别达到80%和85%;最佳的Fe-Mn/ETS-10催化剂负载比(5%Fe-1%Mn/ETS-10)可以提高SCR反应的催化活性。
Abstract: Fe-Mn/ETS-10 catalysts with various compositions were synthesized by high temperature solid state reaction. These catalysts were characterized by X-ray diffractometry(XRD), Fourier transform infrared spectroscopy(IR), scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS). The effect of different amounts of Fe-Mn/ETS-10 on the morphology, composition and the catalytic reduction performance was studied. The results show that Fe-Mn/ETS-10 has good uniformity and dispersion, the morphology and crystal structure of ETS-10 are kept. 5%Fe-1%Mn/ETS-10 has more active sites and higher deNOx performance. The catalysts activity of CO-SCR results show that denitrification rates of 5%Fe-1%Mn/ETS-10 are 80% and 85% at 300 ℃ and 400 ℃, respectively. So, it is concluded that an optimal Fe-Mn/ETS-10 catalyst support ratio (5%Fe-1%Mn/ETS-10) enhances the catalytic activity in the selective catalytic reduction reaction.
DOI: 10.11817/j.ysxb.1004.0609.2020-35899
付国友1,何汉兵1, 2, 3,张 丽1,马 英4
(1. 中南大学 冶金与环境学院,长沙 410083;
2. 武汉科技大学 国家环境保护矿冶资源利用与污染控制重点实验室,武汉 430081;
3. 安徽工业大学 冶金减排与资源综合利用教育部重点实验室,马鞍山 243002;
4. 永清环保股份有限公司,长沙 410001)
摘 要:通过高温固相法制备不同负载量的Fe-Mn/ETS-10催化剂,利用X射线衍射仪(XRD)、傅里叶红外仪(IR)、扫描电子显微镜(SEM)、X射线光电子能谱分析(XPS)等对催化剂进行表征,考察了不同负载量对Mn-Fe/ETS-10形貌、结构组成、以及选择性催化还原(SCR)性能的影响。结果表明:Fe-Mn/ETS-10催化剂具有良好的均一性和分散性,并保持ETS-10原有形貌、晶型;5%Fe-1%Mn/ETS-10具有更多的活性位和更高的脱硝性能。CO-SCR催化性能测试结果显示,5%Fe-1%Mn/ETS-10在脱硝温度300 ℃和400 ℃时脱硝率分别达到80%和85%;最佳的Fe-Mn/ETS-10催化剂负载比(5%Fe-1%Mn/ETS-10)可以提高SCR反应的催化活性。
关键词:Fe-Mn催化剂;催化脱硝;CO-SCR催化性能;ETS-10分子筛
文章编号:1004-0609(2020)-11-2616-11 中图分类号:TB333 文献标志码:A
氮氧化物(NOx)是大气污染和生态破坏的主要污染源之一,会产生酸雨、臭氧层空洞等诸多环境问题。选择性催化还原技术(SCR)是脱硝的主流途径,催化剂及还原剂的选择是核心。CO是一种典型的还原 剂[1-2],被广泛用于选择性催化还原NO(CO-SCR),同时,广泛存在于汽车尾气及工业废气中,因此,可达到以废治废的目的[3],此外CO、NOx和SO2[4]之间可以很好地相互作用,从而可用于同时脱硫脱硝[5]。目前,研究最多的脱硝催化剂是金属氧化物催化剂,主要包括Pt、Pd、Ir等贵金属催化剂,以及Fe、Ni[6]、Co[7]、Mn、Cu[8-9]、Ce[10]等过渡金属催化剂。贵金属资源有限,成本过高,发展受到限制。因此,脱硝领域开发低价环保型催化剂受到越来越多的关注。
1989年,Engelhard公司首次报道合成钛硅酸盐ETS-10(组成为(Na,K)2Si5TiO13·4H2O),具有典型的微孔结构[11]。ETS-10框架由[SiO4]四面体和[TiO6]八面体组成,两者通过氧桥相连。ETS-10三维结构中包含5元环、7元环和12元环,不同孔道之间可以互通。其微孔相对较大(0.76 nm×0.49 nm),比表面积和孔体积较高,独特的钛骨架配位,使其具有良好的热稳定性和选择性[12]。
ETS-10既具有铝硅酸盐沸石的离子特性又具有结晶硅酸盐分子筛的非极性特性[13],因此,在催化氧 化[14]、离子交换[15]、光催化[16]和分子吸附分离[17]等领域有广阔的应用前景。关于ETS-10在脱硝领域的研究较少。BORDIGA等[18]利用红外光谱证明Cu-ETS-10在NO分解中具有催化活性。SULTANA等[19]采用浸渍法制备了Mn/ETS-10用于NH3-SCR。SONG等[20]制备高活性的Cu-ETS-10钛硅酸盐催化剂用于NOx氨气选择性催化还原。JIN等[21]通过挤压成型法用CeO2改性了一系列Mn-Mo-W-Ox/TiO2-SiO2催化剂,用于协同催化去除CO,NO和C3H8。上述研究表明,ETS-10在脱硝领域的应用及反应机理尚待研究,然而关于ETS-10载体用于CO-SCR体系的研究少有报道。
研究表明,铁锰金属负载于分子筛、Al2O3、TiO2、碳纳米管等,制备成负载型催化剂具有理想的SCR活性。WANG等[22]通过浸渍法制备一系列铁掺杂量不同的Mn-Fe/ZSM-5催化剂,考察铁改性催化剂的NH3-SCR活性,发现通过引入铁显着增强了快速SCR反应和NO氧化过程中的催化活性。ZHOU等[23]选择Beta分子筛作为载体,制备Fe-Mn/Beta催化剂,研究其在富氧条件下C3H6-SCR性能,350 ℃最高可达99.4%脱硝率。WANG等[24]制备了一系列Fe-Mn/Al2O3催化剂并进行了低温选择性催化研究(NH3-SCR),研究了Fe-Mn比例对NO转化率和催化剂失活的影响,其高活性归因于铁和锰氧化物更高的分散度、更好的氧化还原性能和表面酸度、更多的表面吸附氧和更低的结合能。HUANG等[25]制备了蜂窝状Ho改性的Fe-Mn/TiO2催化剂,研究了结构助剂等对成型催化剂NH3-SCR性能的影响。ZHANG等[26]采用氧化还原共沉淀法制备用于NH3-SCR体系的Mn-FeOx/CNTs催化剂,催化剂具备非晶态结构,高形态稳定性,化学吸附的氧含量高,还原性强,在32000 h-1的高空速下于140~180 ℃表现出80%~10%的脱硝率。Fe-Mn催化剂表现出高的催化活性[27]及抗水抗硫性[28]。
因此,选用Fe、Mn负载于ETS-10上制成催化剂进行研究。以钛硅分子筛负载过渡金属作为脱硝催化剂,研究其脱硝活性,讨论负载型催化剂中过渡金属铁及锰存在形态与CO-SCR反应催化活性之间的关系。
1 实验
1.1 催化剂制备
采用高温固相法制备负载型Fe-Mn/ETS-10催化剂。
1.1.1 ETS-10载体制备
通过水热法制备ETS-10初始凝胶组成:n(SiO2): n(TiO2):n(Na2O):n(K2O:n(H2O):n(H2SO4)=5.5:1.0:3.7: 0.95:171:2.82。其具体量为:1.56 g H2SO4和4.32g Ti(SO4)2,溶于18 mL去离子水中,搅拌1 h,记为A溶液;5.34 g NaOH和3.21 g KF·2H2O,溶于23 mL 去离子水中,搅拌1 h,记为B溶液;将A、B溶液均匀混合,均匀搅拌4 h,置于50 mL聚四氟乙烯高压釜中,200 ℃恒温反应48 h,经过离心、洗涤、干燥,得到ETS-10白色粉末。
1.1.2 Fe-Mn/ETS-10催化剂制备
实验前期已完成Fe/ETS-10负载量探索实验,得到Fe与ETS-10质量比为5%。选择在5%Fe/ETS-10基础上分别负载不同比例的Mn,质量比设定为5%Fe-xMn/ETS-10(x=0%、0.5%、1%、2.5%、5%,其中x为Mn与ETS-10质量分数)。
按照计算好的比例,准确称量ETS-10样品,硝酸铁,50%(质量分数)硝酸锰溶于无水乙醇。2) 在水浴80 ℃条件下搅拌蒸干,烘干12 h。3) 研磨0.5 h,置于马弗炉中以 5 ℃/min升温速度升到550 ℃(此最佳温度由前期烧结温度条件实验所确定),保温4 h,再自然降温至室温,即得到目标产物。
1.2 催化剂物化性能表征
采用日本Rigaku D公司TTR Ⅲ型X射线衍射仪(XRD)对所合成的材料进行物相结构的检测,Cu靶(λ=1.5406 ),扫描范围2θ为10°~80°,扫描速度为10 (°)/min;JSM-6360LV型电子扫描显微镜对材料进行表面微观形貌观察和能谱面扫描元素成分分析;Nico-let6700傅里叶红外光谱仪(FT-IR)对分子结构进行定性定量分析;Thermo Fisher公司ESCALABXi+测定固体表面的电子结构和表面组成的化学成分。
1.3 催化剂脱硝性能表征
通过实验室对合成的催化剂进行脱硝性能检测实验。实验体系由配气系统、催化系统、检测系统3个部分组成,配气系统由装有CO、NO标准气的钢瓶和配气仪组成,催化系统由固定反应器和管式电阻炉组成,检测系统为德国MRU公司VARIO PLUS型增强型烟气分析仪。
采用抗高温石英棉将0.5 g 催化剂固定于石英管中部,放置于程序控温的管式电阻炉中进行反应。在500 ℃下,1% CO+99% N2 (摩尔分数)微还原气氛中,催化剂预处理1 h。然后通入反应气体:w(CO)= 600×10-6,w(NO)=500×10-6,平衡气氛为氮气,再经过程序性升温控制以5 ℃/min的速度从50 ℃升至600 ℃进行脱硝率测试。利用烟气分析仪检测并实时记录出口处NO浓度脱硝率()计算公式如下:
(1)
式中:为进口处NO浓度;为出口处NOx浓度, 包括NO和NO2。
2 结果与讨论
2.1 XRD表征及分析
图1(a)所示为ETS-10的XRD谱,在12.3°、12.9°、20.1°、23.8°、24.7°、25.8°、27.1°、31.8°、35.3°、35.6°、36.5°、37.0°处出现衍射峰,分别对应ETS-10的(101)、(004)、(105)、(200)、(202)、(116)、(204)、(109)、(217)、(208)、(224)、(110)和晶面[29-30]。这是ETS-10分子筛结构的特征,与模拟的衍射峰位置相对应[31-32]。图1(b)所示为Fe-Mn/ETS-10样品的XRD检测结果。将Fe、Mn负载到ETS-10上后,主要衍射峰位置均未发生变化,说明Fe、Mn的负载不会影响ETS-10的晶体结构。衍射峰的强度略有降低,尤其是2θ为24.7°和35.6°位置,分别对应原ETS-10的(202)和(208)晶面。
在Fe-Mn/ETS-10的XRD谱中未观察到较为明显的与Fe和Mn物种相关的峰。根据相关文献表明,在本实验条件下,Fe及Mn物质的存在形式一般是氧化物(Fe2O3,MnO2等)[33-34],在图谱中未出现明显氧化物衍射峰。可以推断,铁、锰物质以无定形状态存在,或尺寸非常小的金属氧化物颗粒分散在样品中,小于XRD谱的极限检测值[35]。
2.2 SEM表征及分析
图2所示为ETS-10及Fe-Mn/ETS-10样品扫描电子显微镜图片。图2(a)可看出,ETS-10为截取顶端的双锥体,形貌规整,晶体尺寸为3 μm左右,与文献[30]相符,辅助验证成功合成ETS-10。图2(b)~(f)为Fe-Mn/ETS-10样品形貌,对比图2(a)可看出,ETS-10载体形貌基本保持,有小颗粒包覆在ETS-10基体的表面,推测小颗粒为锰及铁氧化物颗粒。
5%Fe-1%Mn/ETS-10样品的X射线能谱元素面分布分析(SEM-EDAX)结果如图3所示,分别为扫描区域,Na、K、Ti、Si、O、Mn、Fe的分布图,证实了Fe和Mn物质的存在,且在ETS-10载体表面分散均匀。
图1 ETS-10与Fe-Mn/ETS-10的XRD谱
Fig. 1 XRD patterns of ETS-10(a) and Fe-Mn/ETS-10(b)
图2 ETS-10与Fe-Mn/ETS-10的SEM像
Fig. 2 SEM images of ETS-10 and Fe-Mn/ETS-10
图3 5%Fe-1%Mn/ETS-10的SEM像及相应的元素面扫描分布
Fig. 3 SEM image and EDAX element mappings distribution of 5%Fe-1%Mn/ETS-10
2.3 FTIR表征及分析
图4所示为FTIR谱。样品ETS-10在500~4000 cm-1范围内出现的吸收峰的强度和位置与文献 [36-37]中的相符。其中547.69 cm-1对应于Si—O振动特征峰以及O—Ti—O弯曲振动特征峰,744.40 cm-1处的峰对应Ti—O伸缩振动特征峰,在973.89 cm-1处的峰是由于ETS-4中的Si—O—Ti键出现在ETS-10中引起的,1029.81 cm-1处的峰对应Si—O伸缩振动特征峰,1637.29 cm-1的吸收峰以及从3200 cm-1到3600 cm-1的宽峰是水分子伸缩振动特征峰和弯曲振动特征峰。通过分析红外光谱图,可以辅助验证ETS-10分子筛的成功合成,同时表明ETS-10沸石是稳定的催化剂载体。Fe-Mn/ETS-10材料中的Mn,Fe物质及其氧化物仍无法通过FTIR光谱检测到明显特征峰[38-39],推测是由于合成的Fe-Mn/ETS-10样品中的Mn和Fe含量低。
2.4 XPS表征及分析
对Fe-Mn/ETS-10进行XPS检测,通过计算不同负载比例样品中Fe、Mn价态及含量,对比分析其可能的脱硝能力高低顺序。图5所示为Fe-Mn/ETS-10的Fe 2p光谱,其中Fe 2p3/2峰、Fe 2p1/2峰、Fe3+卫星峰[40]如图所示,负载材料中金属Fe主要以二价和三价态形式存在。Fe 2p3/2和Fe 2p1/2较低结合能位置,分别对应710.3 eV和723.8 eV,归属于Fe2+;Fe 2p3/2和Fe 2p1/2较高结合能位置,对应712.7 eV和726.510 eV,归属于Fe3+ [41];另外卫星峰也归属于Fe3+。
图4 ETS-10与Fe-Mn/ETS-10的红外光谱图
Fig. 4 Infrared spectra of ETS-10(a) and Fe-Mn/ETS-10(b)
图5 Fe-Mn/ETS-10的Fe 2p光谱
Fig. 5 Fe 2p XPS spectra of Fe-Mn/ETS-10
通过图5可以通过峰面积计算Fe-Mn/ETS-10中的不同Fe物种的相对含量,结果如表1所示。通常NOx的吸附和还原性能取决于催化剂表面上的Fe种类与Fe含量密切相关,还原反应可看成两个关键步骤:1) CO在催化剂表面的吸附,导致晶体内氧分子的损失,从而产生与还原的金属表面耦合的氧空位;2) NO在还原的表面上的吸附,然后与游离(非键合)CO反应[42]。催化剂包含的游离的铁离子和小的铁氧化物颗粒可以充当NOx吸附的活性中心[43],Fe2O3通过产生氧空位使铁在Fe3+和Fe2+状态之间穿梭,催化剂的脱硝性能受其反应控制,因此分离的和低聚的Fe3+物种及小的Fe2O3团簇是CO-SCR反应的活性物质[44-45]。催化剂表征结果表明,Fe物种分布的重要性,高Fe3+量增加了NOx的吸附量,而更好的Fe物种分布提高了催化活性。5%Fe-1%Mn/ETS-10中不同Fe物种的相对含量较均匀。同时,5%Fe-1%Mn/ETS-10中Fe3+物种及Fe2O3含量最高,及活性中心的含量最多,因此,有利于脱硝反应的进行。
表1 Fe-Mn/ETS-10中Fe元素含量分析
Table 1 Analysis of Fe element content in Fe-Mn/ETS-10
图6所示为Fe-Mn/ETS-10的Mn 2p光谱,其中Mn2O3线、MnO2线如图所示,金属Mn在样品中主要以三价和四价态形式存在,其光谱在高结合能处没有出现振动峰,说明在催化剂表面不存在Mn2+物种。
图6 Fe-Mn/ETS-10的Mn 2p光谱
Fig. 6 Mn 2p XPS spectra of Fe-Mn/ETS-10
Mn 2p3/2出现在约641.4 eV,Mn 2p1/2出现在约653.2 eV[46]。根据研究表明[47],Mn 2p3/2的较高结合能和Mn 2p1/2的较低结合能位置分别对应641.2 eV和652.6 eV,为Mn3+;Mn 2p3/2的较高结合能和Mn 2p1/2较低的结合能位置对应643.4和655.0 eV,为Mn4+,实验数据的拟合结果如图6所示。
通过图6可以通过峰面积计算Fe-Mn/ETS-10中的不同Mn物种的相对含量,结果如表2部分所示。其中,锰氧化物表现出Mn3+和Mn4+价态,多价态使锰氧化物表现出优异的氧化还原性能,表面存在多种类型的不稳定活性氧[48],有利于提高催化活性。在所有过渡金属氧化物中,Mn2O3表现出稳定的CO氧化性能。5%Fe-1%Mn/ETS-10中Mn3+/Mn4+比例最高,有利于三价及四价离子之间的转换,这与其脱硝性能最佳直接相关。
表2 Fe-Mn/ETS-10中Mn元素含量分析
Table 2 Analysis of Mn in Fe-Mn/ETS-10
2.5 催化剂CO-SCR活性测试及分析
图7所示为催化剂在50~600 ℃的脱硝活性曲线,由图可知,不同负载比例的Fe-Mn/ETS-10样品的脱硝性能均随着温度的升高呈增强趋势。对比发现,在50~600 ℃范围内,5%Fe-1%Mn/ETS-10脱硝活性较其他样品更高;300 ℃时,5%Fe-1%Mn/ETS-10脱硝活性达到80.00%;在400 ℃时,5%Fe-1%Mn/ETS-10脱硝活性达85.33%;之后,脱硝率持续上升。其他比例样品在400 ℃脱硝率达到80%以上。由脱硝性能对比可以看出Mn-Fe双金属负载对催化剂的改性主要体现在低温脱硝性能的提高。不同负载比例中5%Fe-1%Mn/ETS-10为活性最高的催化剂,优异的催化活性与其高还原性,更多的结构缺陷和铁与锰的协同作用有关[49]。
图7 Fe-Mn/ETS-10的脱硝率曲线
Fig. 7 Denitrification rate curves of Fe-Mn/ETS-10
3 分析与讨论
根据前文XRD和XPS等表征可分析得到,双金属负载的Fe-Mn/ETS-10催化剂,催化活性受两个方面的影响:1) 孤立的铁离子Fe3+、Fe2O3活性位点的数量;2) 材料中锰氧化物的不同组合(MnO2,Mn2O3)可以在不同温度范围内调整催化性能,因此拓宽了活性窗口。
对于CO-SCR反应,当催化剂与反应气体NO和CO接触时,NO分子优先吸附在活性部位上,形成不同的吸附态NO物种,然后被诱导解离为N和O,之后解离的N原子与NO分子结合形成N2O。最后,CO分子和中间产物N2O转变为气态CO2及最终产品N2。普遍认为反应遵循Langmuir-Hinshelwood(L-H)机理[50]。其中,NO的解离是通过CO去除NO的关键步骤,氧空位可以激活N—O键以促进NO的解离[51]。
在Fe-Mn/ETS-10催化剂中,Fe2O3产生氧空位使铁在Fe3+和Fe2+价态转换;同时,铁和锰之间的相互作用可以有效地产生表面协同氧空位活性中心,表面协同氧空位只能在双金属催化剂中生成,而不能在单金属或单金属的机械混合物中生成[52]。由于表面氧空位及表面协同氧空位的共存,Fe-Mn双金属催化剂活性提高。
同时,对于NO+CO反应,Fe3++Mn3+Fe2++Mn4+氧化还原平衡,可以促进电子在各种活性组分之间的转移和交换。因此,平衡比例的铁物种(Fe3+、Fe2+)及锰物种(Mn3+、Mn4+),多价态金属离子比例影响电子转移效率,削弱N—O键强度,有助于被吸附的NO物种的解离,从而可以增强CO还原NO的催化活性。这就是5%Fe-1%Mn/ETS-10脱硝活性最高的原因。
4 结论
1) 通过高温固相法成功制备出Fe-Mn/ETS-10催化剂,对催化剂材料的结构、表面形貌、结构、物相组成表征发现,烧结过后的催化剂保持其ETS-10载体原有的晶体结构,保持原有截取顶端的八面椎体形貌,铁及锰金属以高度分散的氧化物形式存在于ETS-10载体表面,参与脱硝反应。
2) 在5%Fe-1%Mn/ETS-10比例下催化剂脱硝活性最高:温度为300 ℃及450 ℃时,其脱硝率分别达到80%及90%。
3) Fe-Mn/ETS-10催化剂中,铁与锰的协同作用有利于活性物质的产生,使Fe,Mn物质不同价态的分布更平均,促进Fe3++Mn3+Fe2++Mn4+氧化还原平衡反应,提高低温下样品脱硝活性。
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FU Guo-you1, HE Han-bing1, 2, 3, ZHANG Li1, MA Ying4
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. National Key Laboratory of Environmental Protection Mining and Metallurgy Resources Utilization and Pollution Control, Wuhan University of Science and Technology, Wuhan 430081, China;
3. Key Laboratory of Metallurgical Emission Reduction and Resources Recycling, Ministry of Education, Anhui University of Technology, Ma’anshan 243002, China;
4. Yongqing Environmental Protection Co., Ltd., Changsha 410001, China)
Abstract: Fe-Mn/ETS-10 catalysts with various compositions were synthesized by high temperature solid state reaction. These catalysts were characterized by X-ray diffractometry(XRD), Fourier transform infrared spectroscopy(IR), scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS). The effect of different amounts of Fe-Mn/ETS-10 on the morphology, composition and the catalytic reduction performance was studied. The results show that Fe-Mn/ETS-10 has good uniformity and dispersion, the morphology and crystal structure of ETS-10 are kept. 5%Fe-1%Mn/ETS-10 has more active sites and higher deNOx performance. The catalysts activity of CO-SCR results show that denitrification rates of 5%Fe-1%Mn/ETS-10 are 80% and 85% at 300 ℃ and 400 ℃, respectively. So, it is concluded that an optimal Fe-Mn/ETS-10 catalyst support ratio (5%Fe-1%Mn/ETS-10) enhances the catalytic activity in the selective catalytic reduction reaction.
Key words: Fe-Mn catalyst; catalytic denitrification; CO-SCR catalyst property; ETS-10 Molecular sieve
Foundation item: Project(2017GK4010) supported by the Scientific Technology of Strategic Emerging Industries and Major Achievement Transformation of Hunan Province, China; Project(2019JJ40378) supported by the Natural Science Foundation of Hunan Province, China; Project(HB201908) supported by Open Foundation of State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control; Project(JKF20-02) supported by Open Foundation of Key Laboratory of Metallurgical Emission Reduction & Resources Recycling of Anhui University of Technology, Ministry of Education, China
Received date: 2019-12-19; Accepted date: 2020-05-13
Corresponding author: HE Han-bing; Tel: +86-13875985605; E-mail: hehanbinghhb@163.com
(编辑 李艳红)
基金项目:湖南省战略性新兴产业科技攻关与重大科技成果转化资助项目(2017GK4010);湖南省自然科学基金资助项目(2019JJ40378);国家环境保护矿冶资源利用与污染控制重点实验室开放基金课题资助项目(HB201908);安徽工业大学冶金减排与资源综合利用教育部重点实验室开放基金资助项目(JKF20-02)
收稿日期:2019-12-19;修订日期:2020-05-13
通信作者:何汉兵,副教授,博士;电话:13875985605;E-mail:hehanbinghhb@163.com