CuFe2O4@GO nanocomposite as an effective and recoverable catalyst of peroxymonosulfate activation for degradation of aqueous dye pollutants

An effective and recoverable CuFe₂O₄@GO catalyst for PMS activation was synthesized and the underlying catalytic mechanism was revealed in this study.     

Combustion synthesis of mesoporous CoAl2O4 for peroxymonosulfate activation to degrade organic pollutants

A mesoporous cobalt aluminate (CoAl₂O₄) spinel is synthesized through a combustion method and adopted for the activation of peroxymonosulfate (PMS) to degrade organic pollutants. Multiple characterization procedures are conducted to investigate the morphology and physicochemical properties of the CoAl₂O₄ spinel. Due to its mesoporous structure, large surface area, and high electrical conductivity, the obtained CoAl₂O₄ exhibits remarkable catalytic activity for Rhodamine B (RhB) degradation. Its RhB degradation rate is 89.0 and 10.5 times greater than those of Co₃O₄ and CoAl₂O₄ spinel prepared by a precipitation method, respectively. Moreover, the mesoporous CoAl₂O₄ spinel demonstrates a broad operating pH range and excellent recyclability. The influence of several parameters (catalyst amount, PMS concentration, initial pH, and coexisting inorganic anions) on the oxidation of RhB is evaluated. Through quenching tests and electron paramagnetic resonance experiments, sulfate radicals are identified as the predominant reactive species in RhB degradation. This paper provides new insights for the development of efficient, stable, and reusable cobalt-based heterogeneous catalysts and promotes the application of persulfate activation technology for the treatment of refractory organic wastewater.     

Degradation of 4-nitrophenol by electrocatalysis and advanced oxidation processes using Co3O4@C anode coupled with simultaneous CO2 reduction via SnO2/CC cathode

Herein, we prepared novel three-dimensional (3D) gear-shaped Co₃O₄@C (Co₃O₄ modified by amorphous carbon) and sheet-like SnO₂/CC (SnO₂ grow on the carbon cloth) as anode and cathode to achieve efficient removal of 4-nitrophenol (4-NP) in the presence of peroxymonosulfate (PMS) and simultaneous electrocatalytic reduction of CO₂, respectively. In this process, 4-NP was mineralized into CO₂ by the Co₃O₄@C, and the generated CO₂ was reduced into HCOOH by the sheet-like SnO₂/CC cathode. Compared with the pure Co0.5 (Co₃O₄ was prepared using 0.5 g urea) with PMS (30 mg, 0.5 g/L), the degradation efficiency of 4-NP (60 mL, 10 mg/L) increased from 74.5%–85.1% in 60 min using the Co0.5 modified by amorphous carbon (Co0.5@C). Furthermore, when the voltage of 1.0 V was added in the anodic system of Co0.5@C with PMS (30 mg, 0.5 g/L), the degradation efficiency of 4-NP increased from 85.1%–99.1% when Pt was used as cathode. In the experiments of 4-NP degradation coupled with simultaneous electrocatalytic CO₂ reduction, the degradation efficiency of 4-NP was 99.0% in the anodic system of Co0.5@C with addition of PMS (30 mg, 0.5 g/L), while the Faraday efficiency (FE) of HCOOH was 24.1 % at voltage of −1.3 V using the SnO₂/CC as cathode. The results showed that the anode of Co₃O₄ modified by amorphous carbon can markedly improve the degradation efficiency of 4-NP, while the cathode of SnO₂/CC can greatly improve the FE and selectivity of CO₂ reduction to HCOOH and the stability of cathode. Finally, the promotion mechanism was proposed to explain the degradation of organic pollutants and reduction of CO₂ into HCOOH in the process of electrocatalysis coupled with advanced oxidation processes (AOPs) and simultaneous CO₂ reduction.     

Co-Fe/SBA-15与过一硫酸盐联用非均相催化降解水中染料罗丹明B

由于硫酸根自由基(SO4?-)的强氧化性,基于SO4?-的高级氧化技术受到人们的高度关注.采用过渡金属活化过一硫酸盐(PMS)产生SO4?-用以分解有机物,反应体系简单,反应条件温和,且不需要额外的能量供给,因此,成为人们优先选用的方法,其中,采用高效、环境友好的非均相过渡金属催化剂活化PMS处理难降解有机物成为研究热点.本文研究了非均相CoFe/SBA-15-PMS体系对水中难降解染料罗丹明B(RhB)的降解.以SBA-15为载体, Co(NO3)2·6H2O和Fe(NO3)3·9H2O为前驱物,采用一步等体积浸渍法制备了CoFe/SBA-15,通过X射线衍射(XRD)、N2吸附-脱附、扫描电镜(SEM)、能谱(EDS)、透射电镜(TEM)和振动样品磁强计(VSM)等对其进行了表征.考察了焙烧温度、Co与Fe的负载量对CoFe/SBA-15催化性能的影响和该催化剂的重复使用性能,还考察了RhB降解动力学及催化剂CoFe/SBA-15投加量、氧化剂PMS投加量和反应物(RhB和PMS)初始浓度对其性能的影响,探讨了RhB的降解机理.结果表明：对于催化剂CoFe/SBA-15,合成焙烧后在SBA-15上负载的Fe、Co化合物主要是CoFe2O4复合物,它作为催化剂的活性中心负载在SBA-15的孔道内外.制备的焙烧温度对CoFe/SBA-15催化性能几乎无影响,但对Co浸出影响显著.与SBA-15相比,催化剂10Co9.5Fe/SBA-15-700(Co和Fe负载量分别为10 wt%和9.5 wt%,焙烧温度700 oC)的比表面积、孔体积和孔径均减小,分别为506.1 m2/g,0.669 cm3/g和7.4 nm,但仍然保持SBA-15的有序六方介孔结构.该催化剂以棒状体的聚集态存在,聚集体直径大于0.25μm,其磁化强度为8.3 emu/g,因此,可通过外磁铁容易地从水中分离.相比之下,10Co9.5Fe/SBA-15-700具有最佳的催化性能和稳定性,可使RhB的降解率达到96%以上, Co的浸出量小于32.4μg/L.在CoFe/SBA-15和PMS共存下, RhB的降解符合一级动力学方程, RhB降解速率随CoFe/SBA-15和PMS投加量的增加和初始反应物浓度的减小而提高.淬灭实验结果表明,在CoFe/SBA-15, PMS和RhB水溶液体系中,存在的主要活性自由基为SO4?-,它是由CoFe/SBA-15活化PMS产生的,对RhB的降解起决定性的作用. RhB降解过程的UV-vis结果表明, RhB的降解途径主要是蒽环打开, SO4?-优先攻击RhB的有色芳香烃环,然后RhB进一步分解为小分子有机物. CoFe/SBA-15循环使用10次仍能保持高催化活性和稳定性,在每次反应中RhB的降解率均大于84%, Co和Fe的浸出量均分别小于72.1和35μg/L. CoFe/SBA-15作为高效、环境友好的非均相催化剂可有效地活化PMS产生SO4?-降解水中RhB,具有实际应用的潜力.     

亚微米级Cu0/Fe3O4复合物多相催化过一硫酸盐降解有机污染物

过一硫酸盐催化活化技术因其可产生强氧化性活性氧化物种,可快速氧化降解并矿化有机污染物的优异性能而备受关注.本文成功制备了亚微米级Cu0/Fe3O4复合物,发现其能多相催化过一硫酸盐产生单线态氧降解有机污染物.首先,以CuCl2·2H2O,FeCl2·4H2O和FeCl3·6H2O为铜源和铁源,水合肼为还原剂,采用水热法在180oC反应24 h制备了亚微米级磁性Cu0/Fe3O4复合物.表征结果显示,所制材料为Cu0和Fe3O4的复合物,颗粒大小约为220 nm;单一相Cu0和Fe3O4晶体粒径分别为33.8和106.2 nm,而Cu0/Fe3O4复合物中Cu0和Fe3O4晶体粒径分别减为20.8和31.9 nm.这表明Cu0和Fe3O4复合降低了Cu0和Fe3O4晶体粒径,有利于Cu0和Fe3O4的分散.BET测试结果表明,Cu0/Fe3O4复合物比表面积为4.6 m2/g,与Cu0颗粒的(4.2 m2/g)相当,但远小于Fe3O4的(15.6 m2/g).制备的Cu0/Fe3O4复合物可有效催化过一硫酸盐产生单线态氧降解罗丹明B、亚甲基蓝、金橙II、苯酚和对氯酚.当Cu0/Fe3O4复合物的用量为0.1 g/L,过一硫酸盐浓度为0.5 mmol/L和初始pH为7时,Cu0/Fe3O4复合物可在30 min内完全降解20μmol/L的罗丹明B、亚甲基蓝、金橙II以及0.1 mmol/L的苯酚和对氯酚.对比试验显示,在相同条件下,Cu0和Fe3O4颗粒分别可以降解28%和20%的罗丹明B.这表明Cu0/Fe3O4复合物中的Cu0和Fe3O4晶体在催化过一硫酸盐降解污染物的反应中具有协同作用,这主要来源于Cu0/Fe3O4复合物中Cu0和Fe3O4的晶体粒径变小和更好的分散.采用分光光度法测定了降解反应液中铜和铁离子的溶出量.当Cu0/Fe3O4复合物的用量为0.1 g/L,过一硫酸盐浓度为0.5 mmol/L和初始pH为7时,反应60 min后,降解液中铜和铁离子的浓度分别为0.22和0.1 mg/L,仅占复合物中总铜和总铁量的1.1%和0.2%,表明Cu0/Fe3O4复合物具有较强的化学稳定性.所制Cu0/Fe3O4复合物具有超顺磁性,借助磁场实现快速分离回收,可循环利用五次,表明其优越的催化稳定性.通过加入乙醇和叠氮化钠,考察了Cu0/Fe3O4复合物催化活化过一硫酸盐体系中的活性氧化物种.发现100 mmol/L乙醇的加入对污染物的降解无明显影响,而加入同等量的叠氮化钠可完全抑制污染物的降解,表明Cu0/Fe3O4复合物催化活化过一硫酸盐产生的主要活性氧物种为单线态氧.采用电子顺磁共振谱进一步证实了单线态氧的生成.基于以上研究,Cu0/Fe3O4复合物催化活化过一硫酸盐的机理为Cu0/Fe3O4作为一个电子媒介加速过一硫酸盐和污染物之间的电子转移,从而导致污染物被快速降解.该反应机理不同于常见的金属催化过一硫酸盐产生硫酸根和羟自由基的反应机理.我们推测,电导性优良的Cu0在此催化反应中起着关键性作用.本催化方法可作为一种绿色的氧化技术用于环境污染物的氧化降解处理.     

Spherical NiWO4-reduced graphene oxide nanocomposite for effective visible light driven photocatalytic activity for the decolourisation of organic pollutants

A hybrid nanocomposite of nickel tungstate – reduced graphene oxide (NiWO₄-RGO) was prepared using a surfactant free hydrothermal approach. Resulting hybrid nanocomposite powder was grounded for forty minutes to ensure homogeneity and avoid agglomerations of particles. Resulting nanocomposite was characterised by XRD, FTIR, FESEM and EDX analysis. Photocatalytic activities of the characterised catalyst were examined by the decolourisation of Methylene blue (MB) and ortho-nitrophenol (ONP) under visible light irradiation were conducted at room temperature. The results confirmed that 15 wt% NiWO₄-RGO composite was degraded almost completely MB (95%) and ONP (82%) within 150 and 240 min respectively under visible light sources. The catalyst was reused and stable for successive six runs with loss of 10% of degradation rate.     

Reduced graphene oxide/ZnFe2O4 nanocomposite as an efficient catalyst for the photocatalytic degradation of methylene blue dye

Research on Chemical Intermediates - This research effort reports the design and development of reduced graphene oxide/zinc ferrite (rGO/ZnFe2O4) nanocomposites for the photo-oxidative degradation...     

Green synthesis of Fe3O4@SiO2‐Ag magnetic nanocatalyst using safflower extract and its application as recoverable catalyst for reduction of dye pollutants in water

This paper reports the green and in situ preparation of Fe₃O₄@SiO₂‐Ag magnetic nanocatalyst synthesized using safflower (Carthamus tinctorius L.) flower extract without the addition of any stabilizers or surfactants. The catalytic performance of the resulting nanocatalyst was examined for the reduction of 4‐nitrophenol (4‐NP), methylene blue (MB) and methyl orange (MO) in an environment‐friendly medium at room temperature. The main factors such as pH, temperature and amount of catalyst influencing the nanocatalyst performance were studied. The apparent rate constants for 4‐NP, MO and MB reduction were calculated, being 0.756 min^?1, 0.064 s^?1 and 0.09 s^?1, respectively. The catalyst was recovered using an external magnet and reused several times with negligible loss of catalytic activity. The as‐synthesized nanoparticles were characterized using powder X‐ray diffraction, transmission electron microscopy, UV–visible, Fourier transform infrared and inductively coupled plasma atomic emission spectroscopies, dynamic light scattering and vibrating sample magnetometry.     

Ultrasound assisted synthesis of starch-capped Cu2O NPs towards the degradation of dye and its anti-lung carcinoma properties

A unique starch encapsulated Cu₂O nanoparticles were synthesized through a simple and ‘green’ route using ultrasonic irradiation. The polar functional groups on the starch (OH) facilitate the NP capping and stabilization. Structural features of the material were assessed over several advanced techniques like fourier transformed infra-red (FT-IR), UV–vis spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), energy dispersive X-ray analysis (EDX) elemental mapping, transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis. It was catalytically explored in reducing an organic dye (Methylene blue - MB) in the presence of NaBH₄ at ambient conditions, being monitored in a UV–vis spectrophotometer. The nanocatalyst was recycled 11 times keeping consistency in its reactivity. Biologically, the nanocomposite exhibited excellent cytotoxicity against lung adenocarcinoma (PC-14, LC-2/ad and HLC-1) cell lines without affecting the normal (HUVEC) cell line. IC₅₀values of the nanocomposite were found at 618, 56 and 379 against HLC-1, LC-2/ad, and PC-14 cell lines respectively and accordingly, PC-14 afforded the best adenocarcinoma activity.     

Facile synthesis and characterization of Fe2O3 nanoparticles using L-lysine and L-serine for efficient photocatalytic degradation of methylene blue dye

In this work, Fe₂O₃ nanoparticles, abbreviated as OL and OS, were facilely synthesized by the combustion procedure using L-lysine and L-serine as organic fuels, respectively. Also, the OL and OS samples were identified using different instruments such as Raman spectrometer, FT-IR spectrophotometer, UV–Vis spectrophotometer, XRD, HR-TEM, BET surface area, and FE-SEM. The XRD confirmed that the mean grain size of OL and OS samples is 42.23 and 33.16 nm, respectively. The HR-TEM images confirmed that irregular, hexagonal, and spherical shapes, have an average diameter of 39.13 and 34.28 nm, were observed in the OL and OS samples, respectively. The BET surface area of the OL and OS samples is 16.20 and 28.34 m²/g, respectively. Additionally, the OL and OS samples were accomplished for the photocatalytic degradation of methylene blue dye in the absence and presence of hydrogen peroxide. The % degradation of 45 mL of 25 mg/L of methylene blue dye in the case of using OL and OS samples in the absence of hydrogen peroxide is 55.23 and 63.64 % after 120 min, respectively. Also, in the presence of hydrogen peroxide, the % degradation in the case of using OL and OS samples is 100 % after 35 and 25 min, respectively.     

Carbon-supported manganese for heterogeneous activation of peroxymonosulfate for the decomposition of phenol in aqueous solutions

Phenolic substances are harmful to humans and other living things, even at low concentrations. Therefore, phenol must be removed from water with the proper process. One of the most effective processes for degrading phenol is heterogeneous catalytic oxidation. Three carbon materials as supports were used to prepare manganese-oxide based catalyst (2.5% MnOx/ACP and 2.5% MnOx/ACN), and graphene oxide (2.5% MnOx/GO). These catalysts were tested for the degradation of phenol in aqueous solution using peroxymonosulfate as a source of sulfate radical. The physio-chemical catalysts were characterised by several characterisation techniques such as powder X-ray diffraction, N₂-sorption (BET), scanning electron microscopy (SEM) equipped with Dispersive Energy X-ray Spectroscopy (EDS). In comparison to other catalysts, heterogeneous activation of peroxymonosulfate was more effectively done by 2.5% MnOx/ACP, resulting in a higher production rate of sulfate radicals. In the presence of a catalyst at 0.2 g and 1 g peroxymonosulfate in 500 mL solution at 25 °C, 90% total organic carbon (TOC) removal and phenol decomposition of 100% was achieved in 90 min with phenol concentration of 75 mg/L. First-order kinetics were followed by phenol decomposition with the energy of activation on 2.5% MnOx/ACP of 15.0 kJ/mol.     

Efficient activation of peroxymonosulfate by hollow cobalt hydroxide for degradation of ibuprofen and theoretical study

Hollow structure cobalt hydroxide (h-Co(OH)₂) was synthesized via a solvothermal-hydrothermal method and presented high activation activity for peroxymonosulfate to degrade ibuprofen.     

CoCr2O4@GeO2@ZnO core-shell nanoparticle as a novel recoverable catalyst: Preparation,characterization and photocatalytic degradation of basic fuchsin dye

Highly photosensitive novel nanostructure CoCr₂O₄@GeO₂@ZnO core-shell UV–Visible light driven photocatalyst have been fabricated by sol-gel method. The double coating of GeO₂ and ZnO on CoCr₂O₄ nanoparticles could intensely stabilize the CoCr₂O₄ in aqueous solution and avoid their oxidation. The synthesized CoCr₂O₄, CoCr₂O₄@GeO₂, and CoCr₂O₄@GeO₂@ZnO nanostructures were characterized by several techniques including FT-IR, XRD, UV-DRS FE-SEM, EDS, HR-TEM and BET analysis. The potential application of CoCr₂O₄@GeO₂@ZnO is examined for photocatalytic degradation of Basic Fuchsin dye in aqueous heterogeneous suspension. The detailed degradation pathway has been established by using LC-MS analysis and by a careful identification of intermediate products. The result suggest that CoCr₂O₄@GeO₂@ZnO photocatalysis may be envisaged as a method for treatment of diluted waste water in textile industries. In the present study, the degradation yield for Basic Fuchsin dye 100% within 30 ​min using core-shell CoCr₂O₄@GeO₂@ZnO nanostructure material.     

CuNPs as an activator of K2S2O8 for the decolorization of diazo dye in aqueous solution

Degradation of trypan blue (TB) by persulfate/CuNPs system was investigated as a function of TB concentration, persulfate concentration, CuNPs concentration, pH, and reaction temperature in aqueous solution. The rate of the decolorization and destruction of aromatic ring were studied spectrophotometrically. The dye mineralization was performed with potassium dichromate for the determination of chemical oxygen demand (COD) in solution. The blue color reaction mixture became red-chocolate, purple, light blue to dark blue as a function of time. The CuNPs acted as an activator of K₂S₂O₈ and generates various reactive oxygen and/or sulphur species. Decolorization of dye starts due to the cleavage of azo bond by the generated radical species. The role of sulfate radicals (SO₄^?-), and hydroxyl radicals (HO^?) were established by using different radical scavengers. Degradation and mineralization of dye follows first-order kinetics. These results can support the design of remediation processes and also assist in predict their fate in environment.     

Fe3O4-CuO-activated carbon composite as an efficient adsorbent for bromophenol blue dye removal from aqueous solutions

Dye wastewater from industries is posing tremendous health hazards. The lethal dyes can be eliminated using nanomaterials and scientific approach like adsorption which is facile, cheap, safe as well as ecofriendly. Fe₃O₄-CuO-AC composite was prepared by a hydrothermal method and used for the removal of dyes in wastewater. The composite material was characterized by various techniques such as XRD, SEM, EDS, TEM and FT-IR. The Fe₃O₄-CuO-AC composite was used to treat five types of dyes in water. Fe₃O₄-CuO-AC composite showed the highest adsorption capability for bromophenol blue (BPB) dye. The effects of initial concentration, pH, the amount of adsorbent and temperature were also studied. The optimum conditions were found to be 20 ppm dye concentration, pH 9, an adsorbent dose of 0.06 gL^─1 at 65 °C. A removal efficiency of 97% was obtained for BPB dye during 120 min of adsorption. Kinetic studies indicated that a pseudo-second order is the most suitable model for the adsorption process. The Fe₃O₄-CuO-AC composite showed better adsorption capacity as compare to Fe₃O₄-AC except for the Methyl green dye. The maximum adsorption capacity was found to be 88.60 mg/g for BPB. Additionally, the thermodynamic parameters (ΔS°, ΔH° and ΔG°) showed that the process was spontaneous and exothermic. All the above results revealed that the Fe₃O₄-CuO-AC compositecan be an effective adsorbent for removing dyes from wastewater.     

High active amorphous Co(OH)2 nanocages as peroxymonosulfate activator for boosting acetaminophen degradation and DFT calculation

Acetaminophen(ACE)is commonly used in analgesic and antipyretic drug,which is hardly removed by traditional wastewater treatment processes.Herein,amorphous Co(O...     

Vanadium supported on spinel cobalt ferrite nanoparticles as an efficient and magnetically recoverable catalyst for oxidative degradation of methylene blue

Vanadium supported on spinel cobalt ferrite nanoparticles was synthesized and characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, energy‐dispersive X‐ray analysis and transmission electron microscopy. For the first time, the prepared material was used for the catalytic degradation of methylene blue as an organic dye in the presence of hydrogen peroxide as a green oxidant and NaHCO₃ as a co‐reagent at room temperature. The dependency of removal percentage on various parameters such as amount of catalyst, pH, reaction time and temperature and the effect of radical scavenging agents were studied. Finally, recoverability and reusability of the vanadium supported on spinel cobalt ferrite nanoparticles were investigated.     

Ultrasound-assisted nanoscaled supramolecular coordination polymer as an efficient recyclable catalyst for photocatalytic degradation of dye pollutants

An ultrasound-assisted nanoscaled supramolecular coordination polymer (nanosized 1′ ) has been synthesized using a self-assembly reaction of K₃[Cu (CN)₄] and hexamethylenetetramine in the presence of Me₃SnCl under ambient conditions. Nanosized 1′ was examined using elemental analysis, Fourier transform–infrared, transmission electron microscopy, scanning electron microscopy and X-ray powder diffractions. It was structurally compared with the single crystal supramolecular coordination polymer ^∞₃[Cu₆(CN)₇(C₆H₁₂N₄)₂(OH₃)]; SCP 1. The photocatalytic activities of nanosized 1′ and SCP 1 toward different hazardous organic dyes were determined under ambient, UV-light irradiation and ultrasonic conditions. SCP 1 and nanosized 1′ as heterogeneous nanoparticles catalysts exhibited high catalytic activity for degradation of Congo Red, Methyl Violet 2B and Methylene Blue dyes. The effects of operational parameters on catalytic degradation process, identification of the degradation products and recycling of the catalyst were also investigated. SCP 1 and nanosized 1′ are recyclable heterogeneous catalysts and can be reused with efficient activities. The mechanism of degradation using different scavenger techniques iss proposed and discussed. The catalytic oxidation process is mainly caused by ^•OH radicals.     

Mn3O4/金属有机骨架材料活化过一硫酸盐降解水中难降解有机污染物罗丹明B

锰氧化物是一类环境友好型材料,可以有效活化过一硫酸盐(PMS)降解水中难降解有机污染物.但是锰氧化物在单独使用时容易出现严重的团聚现象,进而降低其对PMS的催化活性,不利于水中污染物的降解.因此,人们通常将锰氧化物负载于多孔的载体材料上.金属有机骨架材料(MOFs)因具有巨大的比表面积和温和的制备条件而广受关注.本文采用温和的溶剂热法首次成功制备了Mn3O4与MOF的复合材料Mn3O4/ZIF-8,并通过X射线衍射、扫描电镜、透射电镜、X射线光电子能谱和红外光谱等手段对其进行了表征,探究了Mn3O4/ZIF-8的形成机理.考察了Mn3O4负载量对Mn3O4/ZIF-8催化性能的影响,以及Mn3O4/ZIF-8投加量、PMS投加量、初始罗丹明B(RhB)浓度和反应温度对RhB去除效果的影响,同时探究了Mn3O4/ZIF-8的重复使用性能,分析了RhB的降解途径、去除机理以及最终的降解副产物.结果表明,边长为50?150 nm的片状Mn3O4均匀分散在粒径为250 nm的六边形ZIF-8的外表面;当Mn3O4负载量为0.5时,所制备的复合材料0.5-Mn/ZIF-120活化PMS对RhB的降解效果最好,反应60 min时RhB降解率可达到99.4%,且Mn的浸出量可以忽略不计.在该体系中,RhB的降解过程符合一级动力学反应方程,其降解速率常数随催化剂和PMS投加量的增加、反应温度的提高和初始RhB浓度的减小而增大.在0.5-Mn/ZIF-120催化剂投加量为0.4 g/L、PMS投加量为0.3 g/L、初始RhB浓度为10 mg/L、初始溶液pH为5.18及室温(23oC)条件下,水中RhB的降解率在40 min时即可达到98%.淬灭实验表明,该体系中HO?起主导作用,而其主要来源于活化PMS所产生的SO4–?.此外,通过简单的二次水冲洗方式对0.5-Mn/ZIF-120催化剂进行回收使用,在连续5次循环使用后仍然可见较高的催化活性和稳定性,RhB的去除率保持在96%以上,且Mn的浸出百分率始终低于5%.