Origin and controlling factors of chlorite coatings—an example from the reservoir of T_3x Group of the Baojie area,Sichuan Basin,China

The study of the chlorite coatings always attracts scholars in China and other countries because the chlorite coatings play an important role in the preservation of residual primary pores in sandstone reservoirs.At present,the study of the origin and the controlling factors is relatively few.The occurrence,time of formation,genesis,controlling factors,and the mechanism of chlorite coatings inhibiting quartz overgrowths were studied in detail with thin section and SEM analysis.Samples were from the sandstone reservoirs of the T3x Group in the Baojie area,the transitional zone from the middle to the south of Sichuan Basin.The results indicate that the chlorite coatings on the walls of the pore spaces are oriented perpendicular to grain surfaces in the form of isopachous(even-thickness) grain-coating,while the chlorite coatings at the contacts between adjacent detrital grains are arranged with a preferred orientation tangential to the surface of detrital grains.The chlorite coatings were formed in the eogenetic stage.They were formed by recrystallization of Fe-rich clay films during the syndepositional period,and chlorite cements would be recrystallized after the coatings' formation.The formation of chlorite coatings was mainly controlled by the depositional environment,provenance conditions,and diagenetic environment.The presence of chlorite coatings could result in the preservation of primary pores in deeply buried sandstone reservoirs by effectively inhibiting quartz overgrowths and the development of compaction and pressure solution.

Selective depression action of taurine in flotation separation of specularite and chlorite

Chlorite,as the most representative gangue mineral associated with specularite,of which the separation of these two minerals is difficult.This paper investigated the depression effect of taurine on specularite/chlorite separation via flotation experiments,adsorption tests,contact angle measurements,Zeta potential detection,FT-IR measurements,and XPS analyses.The results of single mineral flotation indicated that chlorite could be depressed selectively by taurine with the recovery of less than 30%,but the floatability of specularite remains high with recovery rate of 81.77%at pH 10.The artificial mixed mineral flotation results confirmed the effectiveness of taurine as a depressant.Surface adsorption,contact angle,and Zeta potential detection revealed taurine primarily adsorbs on the chlorite surface,which hampered the DDA’s subsequent adsorption and results in the chlorite’s poor floatability.The FT-IR spectra and XPS analyses provided further proof that taurine adsorbed on chlorite surface as an electron donor,and part of the electrons transferred from the sulfonic acid group of taurine to metal ions during the adsorption process.In addition,the hydrogen bond between amino-group of taurine and O ions in chlorite surface was also formed in the adsorption process.Finally,optimized adsorption configurations of taurine on chlorite surfaces were proposed.

Geochemistry and Tectonic Significance of Chlorite Amphibolite in Nanfen BIF, Benxi Area, Northeastern China

Benxi area, Northeastern China, is the main distribution area of Archean BIF-hosted iron deposits in China. In this area, Nanfen iron deposit is well known as the largest open-pit iron deposit not only in China but also in Asia. So far, the tectonic nature during Archean BIF formation period in Benxi area has been long disputed and the tectonic setting of Nanfen BIF had not been found. In this study, the geochemical characters of chlorite amphibolites closely associated with BIF have been investigated for the tectonic environment of Nanfen BIF. Chlortie amphibolites show the geochemical affinity to the back-arc basin basalt (BABB), indicating that the tectonic environment of Nanfen BIF is the back-arc basin. In conjunction with geological evidence of other BIFs at Benxi area, it is identified that BIF in Benxi area might be formed in the subduction-related back-arc basin, which provides a favorable sedimentary environment of Algoma-type BIF.

Mineralogical Characteristics and Short-wave Infrared Spectra of Chlorite as Indicators of Hydrothermal Centers: A Case Study of the Giant Porphyry Copper-Molybdenum Deposit at Qulong, Tibet

The Qulong deposit in Tibet is one of the largest porphyry copper-molybdenum deposits in China. We used short-wave infrared(SWIR) spectroscopy to examine the spectral characteristics of the extensively developed chlorite in this deposit. X-ray diffraction and electron microprobe analyses were used for phase identification and to obtain the chemical composition, ion substitution relationships, and formation environment of the chlorite. SWIR spectral parameters were applied to detect the hydrothermal centers. The results indicate that the wavelength of the absorption feature for Qulong chlorite Fe-OH(Pos2250) range from 2240 to 2268.4 nm;the chlorite substitution relationships are dominated by Mg-Fe substitution at the octahedral sites together with Al;-Si substitution at the tetrahedral sites;the chlorite formation temperatures range within the medium-low temperature hydrothermal alteration range from 164 to 281°C, with an average value of 264℃;the wavelength of the chlorite peak position for Fe-OH(2250 nm) absorption and its chemical composition are positively correlated with Al^(Ⅵ), Fe + Al^(Ⅵ), Fe/(Fe + Mg), Fe, and Fe + Al^(Ⅳ)but negatively correlated with Mg and Mg/(Fe + Mg);and the wavelength associated with the chlorite Fe-OH(2250 nm) absorption feature is positively correlated with the temperature at which the chlorite formed. These correlations indicate that more Fe and Al^(Ⅵ) ions and fewer Mg ions at the octahedral sites of chlorite lead to a longer the wavelength of the chlorite Fe-OH(2250 nm) absorption feature and a higher chlorite formation temperature. The wavelength of the Qulong chlorite Fe-OH(2250 nm) absorption feature(>2252 nm) can thus serve as an exploration indicator to guide the detection of hydrothermal centers in porphyry copper deposits. The results of the study indicate that the mineralogical and SWIR spectral characteristics of chlorite are significant indicators for locating hydrothermal centers within porphyry deposits.

Antimicrobial Activity of Acidified Sodium Chlorite and Cell Free Culture Supernatent of Lactic Acid Bacteria against <i>Salmonella</i>Typhimurium

Most methods used by food industries to decontaminate eggs involve washing of egg surface with various chemicals. In this study, the effectiveness of two organic decontaminants viz., acidified sodium chlorite (ASC) and cell free culture supernatant (CFCS) of two lactic acid bacteria (Lactobacillus plantarum and Pediococcus cerevisiae) was evaluated for the decontamination of spiked Salmonella Typhimurium on chicken egg shell surface. Acidified sodium chlorite at 100 μl/L concentration with the contact time of 20 min completely inhibited S. Typhimurium on egg shell surface while at 50 μl/L concentration 1 - 2 log10 units reduction was observed in counts of S. Typhimurium as compared to control group. Likewise, CFCS of P. cerevisiae completely inhibited the growth of S. Typhimurium on 30 min contact, whereas L. plantarum and combination of both were revealed significant reduction in the counts of S. Typhimurium counts.

Magnesium isotopes of chlorite-rich hydrothermal sediments in the Okinawa Trough and indications for Mg cycle

Seafloor hydrothermal systems play a significant role in the oceanic Mg cycle due to ubiquitous deposits of secondary Mg-rich clays during the strong fluid-rock reactions.However,the magnitude of net Mg enrichment and Mg isotopic fractionation,particularly within the medium-high temperature hydrothermal systems in felsic-hosted settings,are not well studied yet.Here we report elemental and isotopic compositions of Mg in hydrothermal chlorite-rich sediments,volcanic materials,and terrigenous sediments collected during the IODP Expedition 331 drilled to the thick sediment-covered and felsic-hosted middle Okinawa Trough(Iheya North Knoll) in the West Pacific.We investigate the sources of Mg in chlorite and Mg isotopic behavior at medium-high temperature hydrothermal alteration.After 1 mol/L HCl leaching,Mg isotopic compositions of chlorite-rich sediments present overall similar values in the residual fractions and bulk samples albeit with slightly higher values in the leachates.Mineralogical differentiation primarily determines the Mg isotopic compositions,showing that siliciclastic residues have slightly higher δ^(26) Mg values than the leachates dominated by carbonates and oxides/hydroxides.Significant Mg isotopic fractionation happened in the medium-high temperature(~150°C to 260°C) felsic-hosted hydrothermal system,with Δ^(26)MgChl-SW ranging from 0.15‰ to 0.71‰ and yielding a negative correlation with temperature.This observation suggests the preferential incorporation of heavy Mg isotopes by the secondary chlorite precipitation.We infer that the medium-high temperature hydrothermal systems can take up about 8–14% of riverine input of Mg in the arc and back-arc regions.Incomplete removal of aqueous Mg in porewater and vent fluids by the medium-high temperature hydrothermal alterations in the arc and back-arc basins provides constraints on the Mg budget and isotopic composition of seawater.

Iron species activating chlorite:Neglected selective oxidation for water treatment

Chlorite(ClO_(2)-)is the by-product of the water treatment process carried out using chlorine dioxide(ClO_(2))as an effective disinfectant and oxidant;however,the reactivation of ClO_(2)
has commonly been overlooked.Herein,it was unprecedentedly found that ClO_(2)
could be activated by iron species(Feb:Fe0,FeII,or FeIII),which contributed to the synchronous removal of ClO_(2)
and selective oxidative treatment of organic contaminants.However,the above-mentioned activation process presented intensive Ht-dependent reactivity.The introduction of Feb significantly shortened the autocatalysis process via the accumulation of Cl
or ClO
during the protonation of ClO_(2)
driven by ultrasonic field.Furthermore,it was found that the interdependent high-valent-Fe-oxo and ClO_(2),after identification,were the dominant active species for accelerating the oxidation process.Accordingly,the unified mechanisms based on coordination catalysis([FeN(H_(2)O)a(ClOxm)b]nt-P)were putative,and this process was thus used to account for the pollutant removal by the Feb-activated protonated ClO_(2).This study pioneers the activation of ClO_(2)
for water treatment and provides a novel strategy for“waste treating waste”.Derivatively,this activation process further provides the preparation methods for sulfones and ClO_(2),including the oriented oxidation of sulfoxides to sulfones and the production of ClO_(2) for on-site use.

Evolution of chlorite composition in the Paleogene prototype basin of Jiyang Depression, Shandong, China, and its implication for paleogeothermal gradient

The Dongying Basin, Huimin Basin, and Zhanhua Basin constitute the Jiyang Depression in Shandong Province. They are major oil and gas exploring districts within the depression. Through reconstruc-tions of the paleotemperature of the three basins facilitated with the chlorite geothermometry, the thermal history of the Paleogene prototype basin in Jiyang Depression and its geologic significance were explored. This study reveals that the Si4+ component in chlorites reduces gradually as its buried depth increases, while the AlIV component increases accordingly. The chlorite type changes from sili-con-rich diabantite to silicon-poor ferroamesite and prochlorite. The prochlorite in this district only appears in the deep buried depth, high temperature, and relatively old stratigraphies; while the diaban-tite appears in the shallower buried, low temperature, and newly formed strata; the ferroamesite exists in the conditions between prochlorite and diabantite formation. The diagenetic temperatures of the chlorites in these Paleogene basins are 171―238℃ for the Dongying Basin, 160―202℃ for the Huimin Basin, and 135―180℃ for the Zhanhua Basin. The differences of the chlorite diagenetic temperatures in the three basins were controlled by the duration time of the structural depressing processes. Higher temperature indicates longer depression time. The relationship between the chlorite diagenetic temperature and its buried depth indicates that the average paleogeothermal gradient is about 38.3℃ /km in the Paleogene prototype basin of Jiyang Depression. It was higher than the present geothermal gradient (29―30℃/km). This phenomenon was attributed to the evolution of the structural dynamics in the depression basin.

Effects of reductive inorganics and NOM on the formation of chlorite in the chlorine dioxide disinfection of drinking water

Chlorine dioxide(ClO_(2))disinfection usually does not produce halogenated disinfection byproducts,but the formation of the inorganic by-product chlorite(ClO^(–)_(2))is a serious consideration.In this study,the ClO^(–)_(2)formation rule in the ClO_(2)disinfection of drinking water was investigated in the presence of three representative reductive inorganics and four natural organic matters(NOMs),respectively.Fe^(2+)and S^(2–)mainly reduced ClO_(2)to ClO^(–)_(2)at low concentrations.When ClO_(2)was consumed,the ClO^(–)_(2)would be further reduced by Fe^(2+)and S^(2–),leading to the decrease of ClO^(–)_(2).The reaction efficiency of Mn^(2+)with ClO_(2)was lower than that of Fe^(2+)and S^(2–).It might be the case that Mn O 2 generated by the reaction between Mn^(2+)and ClO_(2)had adsorption and catalytic oxidation on Mn^(2+).However,Mn^(2+)would not reduce ClO^(–)_(2).Among the four NOMs,humic acid and fulvic acid reacted with ClO_(2)actively,followed by bovine serum albumin,while sodium alginate had almost no reaction with ClO_(2).The maximum ClO^(–)_(2)yields of reductive inorganics(70%)was higher than that of NOM(around 60%).The lower the concentration of reductive substances,the more ClO^(–)_(2)could be produced by per unit concentration of reductive substances.The results of the actual water samples showed that both reductive inorganics and NOM played an important role in the formation of ClO^(–)_(2)in disinfection.

Impact of chlorites on the wettability of tight oil sandstone reservoirs in the Upper Triassic Yanchang Formation,Ordos Basin,China

Wettability is an essential property of reservoirs that is of great importance for enhancing oil recovery(EOR)and oil migration.The wettability of reservoirs is generally believed to be strongly affected by mineral compositions but it is not always the case.An integrated study of petrography and wettability was carried out to determine the impact of chlorite minerals on the wettability of the sandstone reservoirs in the Upper Triassic Yanchang Formation.Chlorites are found to be commonly present in the reservoir sandstones as detrital grains,rim-shaped cements,and biotite-chloritized forms with the pore peripheries being largely coated by chlorite,which is the main mineral in direct contact with pores.At pore scale,the wetting state of chlorites can either be oil-wet or water-wet in the tight sandstone reservoirs depending on wettability alteration by oil charge.Chlorites in contact with pores occupy a large of proportions of oil-wet pore walls and are crucial for the formation of oil-wetting state of reservoir sandstones.At core scale,the contents of chlorites in direct contact with pores do not correlate well with the AmottHarvey index due to other factors such as heterogeneity,oil-bearing degrees of samples.

THE ELECTRON MICROSCOPY STUDY ON THE MIXED LAYER OF ILLITE AND CHLORITE

Clay minerals having the same type of octahedral layer commonly occur as mixed layers. With the application of electron microscopy in day mineralogy, it is recognized that clay minerals which have different octahedral sheets can also form mixed layers, such as the mixed layer of illite and chlorite which has been well studied. However, there are different opinions on its origin. Based on the study of transmission electron microscopy (TEM)

A novel co-catalyzed system between persulfate and chlorite by sonolysis for removing triphenylmethane derivative

Triphenylmethane(tpm) derivatives(e.g. tpm CV) have threatened the safety of the aquatic environment due to the potential toxicity and carcinogenicity. In this study, the novel ultrasonic/persulfate/chlorite(US/S_(2)O_(8)^(2-)/ClO_(2)^(-)) oxidation process was developed for the effective removal of tpm CV in wastewater. The apparent non-integer kinetics( n around 1.20) of tpm CV degradation under different factors( R^(2)_(Adj) > 0.990) were investigated, respectively. Inhibiting effects of anions were greater than those of cations(except Fe(Ⅱ/Ⅲ)). The adding of micromolecule organic acids could regulate degradation towards positive direction. The double response surface methodology(RSM) was designed to optimize tpm CV removal process, and the acoustic-piezoelectric interaction was simulated to determine the propagation process of acoustic wave in the reactor. The possible degradation pathway was explored to mainly include carbonylation, carboxylation, and demethylation. The estimated effectivemean temperature at the bubble-water interface was calculated from 721 to 566 K after introducing the ClO_(2)^(-), however, the adsorption or partitioning capacity of tpm CV in the reactive zone was widened from 0.0218 to 0.0982. The proposed co-catalysis of US/S_(2)O_(8)^(2-)/ClO_(2)^(-)was based on the determined active species mainly including ClO_(2), SO_(4)·^(-), and ·OH. Compared with other US-based processes, the operating cost(3.97 $/m^(3)) of US/S_(2)O_(8)^(2-)/ClO_(2)^(-)with the EE/O value(16.8 k Wh/m^(3)) was relatively reduced.

Diagenesis and Very Low-Grade Metamorphism of the Upper Permian Yangjiagou Formation in Eastern Changchun, China:Evidence from Clay Mineral Geothermobarometers

The metamorphic conditions of the Upper Permian Yangjiagou Formation in eastern Changchun, China, were evaluated based on the mineral assemblage, illite crystallinity, illite polytypism,the b dimension of illite, and the chemical composition of chlorite. The pelitic rocks in the Yangjiagou Formation are characterized by illite + kaolinite + chlorite ± mixed-layer chlorite/smectite and detrital quartz + plagioclase. Illite in the formation has a crystallinity of 0.38-0.55 and comprises mixed 2 M_1 and1 M_d polytypes, indicating a metamorphic temperature of >200℃. Based on the chemical composition of chlorite and the chlorite geothermometer, we estimated diagenetic to very low-grade metamorphic conditions with temperatures of 185℃～204℃. The b dimension of illite varies from 8.992 A to 9.005 A.We used a mathematical algorithm to extend Guidotti and Sassi's(1986) diagram relating illite b dimension with temperature and pressure, and used this diagram, together with illite crystallinity and chlorite chemical composition, to semi-quantitatively estimate the formation pressure at<1.2 kbar. These reveal that the Yangjiagou Formation has experienced very low-grade metamorphism.

The Environment Significance of Aerinite——First Discovered in the UBC Cliffs

To analyze the composition and structure of the pale blue outcrop from the UBC Cliffs and research the environmental significance of aerinite recorded in the sediments, mineral composition, bulk chemical composition and structural analyses were carried out by means of X-ray diffraction(XRD), field emission scanning electron microscope(FESEM), transmission electron microscope(TEM), electron microprobe analysis(EMPA) and X-ray fluorescence spectra(XRF). Quartz, feldspar, mica, chlorite and aerinite as well as a small amount of amphibole, calcite, clinopyroxene, rutile, perovskite and apatite are recorded in the sediments. It is reported for the first time that the aerinite occurs in a high latitude area and in sediments paragenetic with mica and chlorite. The large span in grain size shows a typical characteristic of fluvioglacial sediments. Geochemistry characteristics(CIA, CIW, PIA, WIP and ICV) verify that there is virtually no chemical weathering. Mineralogy and geochemistry features of the UBC Cliffs sediments indicate that aerinite is accommodate to the high latitude and cold, dry climate. As the sediments show high similarity to those of their provenance, they have great significance in the identification of the forming condition and origin of the aerinite.

Experimental Study of Dissolution-Alteration of Amphibole in a Hydrothermal Environment

Amphibole is a rock-forming mineral widely existing on the earth.It is easily dissolved and altered during the later stage of diagenesis and mineralization,and often forms chloritization,which is an important indicator for prospecting.To explore amphibole's dissolution process and alteration mechanism,dissolution experiments were carried out under acidic conditions using pargasite-rich amphibole as raw material,and the effects of temperature,p H,and experiment duration on amphibole alteration were investigated.Experimental samples and products were analyzed using X-ray diffractometer,field emission scanning electron microscope,electron probe micro analyzer,and transmission electron microscopy.It was found that many pores and erosion edges are produced after amphibole dissolution,and there is a clear interface between the dissolved residual portion and the parent.The dissolved residual portion remains in the amphibole phase,but as the temperature and time increase,the intensity of the diffraction peak of the phase in the product decreases,and the peak position shifts to a small angle.Many clay minerals such as chlorite and griffithite formed on the amphibole surface.In an environment with strong acidity(p H=3),the amount of chamosite increases with temperature(180℃→210℃→240℃),whereas clinochlore is only increased in a 150–210℃environment.Griffithite growth was observed in the acidic(p H=6)and low temperature(<180℃)environments.Based on this analysis,large radius Cl–enters the amphibole lattice or cracks to promote dissolution.The Al-poor and Ca-and Fe-rich regions between the edge and core of the amphibole are caused by dynamic equilibrium in amphibole dissolution and alteration process,which is an essential indicator for the beginning of amphibole dissolution-alteration.Diffusion and the coupled dissolution-reprecipitation mechanism accomplishes the process of dissolution and alteration to form clay minerals.The energy of the system determined by temperature and p H is the key to controlling the rate of growth and nucleation of clay minerals.High temperature and strong acidity will dissolve more iron from amphibole,which is conducive to chlorite growth.Compared to chlorite,griffithite is more sensitive to temperature.Griffithite attaches on the amphibole surface with a star-like in a weak acid and low-temperature environment.The results of this study can provide a mineralogical basis for the analysis of hydrothermal alteration processes and the division of alteration zones.

Groundwater Assessment for the NW of Auja Tamaseeh Basin in Tulkarem Area, West Bank

The study aims to assess groundwater in Auja—Tamaseeh basin in Tulkarem area—West Bank. A steady state calibration flow model as well as solute transport model were built using the visual Modflow software. A stress period of 10 years (2005 - 2015) was assigned to study its tendency to contamination. The model results show that there is a pollution risk due to the human activities in the area. The groundwater situation will be harmful if there is no action done by the water-decision makers to preserve the aquifers from deterioration and contamination.

Metasediments in the Alahina Sector and Associated Mineralization (North-Eastern Guinea)

The Alahina sector is located in the North-East of Guinea, precisely in the Siguiri volcano-sedimentary basin. It consists mainly of meta-sediments traversed by Paleoproterozoic pyroclastite, granite, monzogranite and granodiorite veins as well as Mesozoic dolerite and gabbros veins. This article presents new data, on the one hand, on the geochemical petrographic features and the origin of the metasediments of this zone, and on the other hand, on the genetic model of the gold mineralization that they contain. Field observations, as well as petrographic and geochemical studies reveal that the meta-sediments consist of sericite and chlorite schists. They belong to the groups of shales and grauwackes. Their protholites are moderately altered (60 N/YbN = 6.31 - 13.24) and a flat heavy rare earth patterns (HREE). This spectrum is almost identical to those of the “Post-Archean average Australian Shale” and Early Proterozoic Greywackes. Two types of polyphase gold mineralization occur in the Alahina sector: disseminated and veined. They consist of particular of grains and nanoparticles pyrite associated with gold, magnetite, hematite, ilmenite. The hydrothermal alteration accompanying this mineralization consists of silica, microcline, chlorite-epidote-sericite-carbonates.

Authigenic clay minerals and calcite dissolution influence reservoir quality in tight sandstones:Insights from the central Junggar Basin,NW China

Authigenic clays and calcite cements are important in the development of reservoir tightness and the formation of hydrocarbon sweet spots.We investigated Jurassic low-permeability sandstone reservoirs in the central Junggar Basin,NW China,using petrography,mineralogy,porosity,and permeability assessment,and stable C and O isotope analysis to ascertain the influence of authigenic clays and calcites on reservoir quality.Here,we establish the properties and diagenetic processes of the reservoir sandstones,and construct a generalizable model of reservoir quality.The results show that the sandstones are mainly litharenite and feldspathic litharenite and can be classified into ductile-lithic-rich sandstones and ductile-lithic-poor sandstones according to rock composition.The ductile-lithic-rich sandstones are tight(mean porosity?7.31%;mean permeability?0.08 mD)as a result of intense compaction.In contrast,the ductile-lithic-poor sandstones can be classified into five types according to diagenetic process.The formation of favorable hydrocarbon reservoir properties is closely related to the presence of authigenic clays and dissolution of calcite.In particular,kaolinite fills intergranular pores,thereby blocking pore space and reducing reservoir quality.Chlorite coating resists compaction and limits the formation of quartz overgrowths,thereby preserving pore space and enhancing reservoir quality.Calcite controls reservoir quality through both precipitation and dissolution.Calcite precipitation results in reduced reservoir quality,whereby early calcites that were precipitated in formation water resist compaction and provide the basis for subsequent dissolution and late precipitation,whereas dissolution of calcite in mesodiagenesis improves reservoir quality.A generalized model is formulated by relating diagenetic facies types to depth and porosity,providing a reference for other similar reservoirs.Our data suggest that deeply buried tight sandstones can be exploration prospects under favorable conditions involving the presence of authigenic clays and dissolution of calcite,as in the central Junggar Basin of this study.

Influence of wettability of shaly sandstone on rock electricity parameters

It has been found that the existence of chlorite and illite will lead to the rock wettability of oil affinity.Chlorite and illite are developed in shaly sandstone of Yingcheng Formation in Longfengshan area,the saturation index n of 7 rock samples is very high,with the highest of 14.57,whereas the cementation index m is low.The X-ray diffraction of clay and whole rock analysis of 7 shaly sandstone samples are carried out,and the relationship between chlorite and illite content vs.m and n is established.It is concluded that the low m value and high n value are caused by the wettability of rock.In order to verify the influence of wettability on the parameters of rock electricity,this paper discusses the method of making artificial shaly sandstone and the control of wettability.This study provides certain reference for determining the saturation model of shaly sandstone and improving the logging interpretation accuracy of shaly sandstone reservoirs.

Experiments and reaction characteristics of liquid phase simultaneous removal of SO_2 and NO

Experiments of simultaneous removal of SO2 and NO from simulated flue gas,using NaClO2 solution as the absorbent,were carried out in a self-designed bubble reactor,and high simultaneous removal effi-ciencies of SO2 and NO were obtained under the optimal experimental conditions.The mechanism of simultaneous removal based on NaClO2 acid solutions was proposed by analyzing the removal prod-ucts.Possibility and limitation of the desulfurization and denitrification using NaClO2 acid solutions were calculated by thermodynamic methods.Experimental results of reaction kinetics for simultaneous desulfurization and denitrification indicated that the oxidation-absorption processes of SO2 and NO were divided into two zones,namely the fast and slow reaction zones.In the slow reaction zones both were zero order reactions,and in the fast reaction zones,the reaction order,rate constant and activa-tion energy of SO2 reaction with absorbent were 1.4,1.22(mol.L-1)-0.4.s-1 and 66.25kJ.mol-1,respec-tively,and 2,3.15×103(mol.L-1)-1.s-1,and 42.50 kJ.mol-1 for NO reaction,respectively.