Abstract::Based on a brief review of semiconductor photocatalytic mechanism and researches in the past 30 years on TiO2heterogeneous photocatalysis, this paper emphasizes that the natural vanadiferous rutile and its modified products, which have not been investigated by either Chinese or foreign research groups, degrade halogenated organic contaminants. By means of grinding, heating in situ, heating, quenching and electron irradiation, the natural rutile could be modified. The results show that the lattice distortion and defects in the natural rutile are attributed to the fact that part of Ti4+ions are replaced by V5+and other impurity ions such as Fe3+, Cu2+and Zn2+. Grinding rutile samples into powder with the particle size of 70~80μm results in 0.33% increase of their lattice volumes. The lattice volumes distinctly increase by 0.93%~2.13% via heating in situ at 700~1 100℃. On the contrary, quench- ing causes the lattice volumes decrease by 0.01%~0.07%. V5+ions in rutile are modified by heating segregation outwards to the surface, and the corresponding lattice distortion is rehabilitated by the role of reconstruction in certain crystal faces, recrystallization and release of the microstrain. Rutile modified by grinding shows some degree of photocatalystic efficiency in degrading trichloroethylene and tetrachloroethylene and has fair photoactivity. Heating at 1 000℃evidently improves the degradation ratio of rutile for the halohydrocarbons and the rutile quenched at 1 000℃and 1 100℃distinctly shows a higher degradation rate. The rutile modified by electron irradiation, however, has obviously lower degradation ratio for trichloroethylene. Furthermore, through the tentative study of 52 kinds of semiconducting metal oxides and metal sulfide minerals, it is found that, for most metal oxide minerals,the maximal wavelength of the light, which can excite photoelectron, ranges from 249 to 777 nm, corresponding to the visible light, whereas that of metal sulfide minerals is 921 nm, corresponding to the infrared light. Therefore, the photogenerated electron_held pairs could be excited by the visible light. Systemic researches on photocatalysis in minerals can play an unique role in revealing the life process of the earth and the environmental evolution. The researches are very important to the realization of oxidization of organic contaminants, especially the permanent organic contaminants that cannot be degraded by themselves, in the system of the earth ' s surface.

Abstract:There exists isomorphous replacement in the rutile structure, and the most prominent feature is the average content of oxides, being 1.22%, 0.39%, 0.35% and 0.22% for V 2O 5, Fe 2O 3, ZnO and CuO respectively. They substitute Ti 4+ in octahedra. The valence of V is 5, and its polyhedron is trigonal bipyramid, which causes the lattice distortion, breaks the raw octahedron symmetry into square bipyramid, and produces the microstrains in the structure. TEM study shows the defects in rutile, which can result in the photocatalytic active location. The crashing, heating and microwave radiation can cause the expansion of the lattice volumes, lattice distortion and increase of energy, promoting photocatalystic activity. It is certain that the natural rutile can gestate good photocatalystic activity.

Abstract:The natural vanadiferous rutile was modified by heating, quenching and electron irradiation, and the different photoactivities of samples under different treatments were studied. XRD patterns of all samples reveal that all the treatments fail to result in new phases or any phase transition. In the IR spectra, there is a broad band at about 3400 cm -1 in non-modified, heating and quenching samples, which is attributed to the stretching vibrations of OH groups. The IR spectrum of the irradiated sample, however, shows no above_mentioned band. XPS (X-ray Photoelectron Spectroscopy) was used to study the change of chemical characteristics on the sample surfaces. The concentrations of oxygen and vanadium atoms increase with heating and quenching. This may be related to the increase of defects on the surface, which will add active sites for adsorption of water and hydroxyl groups. Accordingly, the photoactivities of these samples are distinctly improved. Unfortunately, electron irradiation fails to accelerate the photoactivity; on the contrary, it even somewhat slows down the process due to the reduction of adsorbed water and hydroxyl groups.

Abstract:Natural rutile was used as a catalyzer to oxidize halohydrocarbons. The result shows that natural rutile has some photocatalytic capability. Such means as electron radiation, quenching and heat treatment were employed to improve the performance of natural rutile, and the ameliorative specimens were used to conduct photocatalytic oxidation of three kinds of halohydrocarbons. The effect shows that both quenching and heat treatment can improve the performance of rutile as a catalyzer. The tetrachloroethylene and trichloroethylene can be decomposed from 400μg/L to 5μg/L, whereas electron radiation seems not a feasible method to improve natural rutile. The study has laid a foundation for further researches.

Abstract:The main goal of a series of Laboratory experiments was to determine the efficency of iron for removing hexavalent chromiun.The results indicate that the reductive reaction of zero-valent iron with hexavalent chromium reaches the quasi- first-order standard,that the ratio of the granular iron (BTE2.89m2/g)to solution increases from 0.5g/100 ml to 2.0g/100ml,and that the reaction time is reduced from 26.7 min to 3.6 min. It is also shown that the reaction time should be prolonged to meet the standard of dringking water because the concentration of initial solution within 30 mg/L increases when the quantity of iron is stable,and that the raising of the temperature promotes the removal of hexavalent chromium when other conditions are constant.

Abstract:The main affecting factors and adsorption isotherms in the application of natural iron-bearing oxides and hydroxides to the treatment of Hg(Ⅱ) wastewater were studied with the theory of adsorption of heavy metal ions on the surface of water_metal oxides and hydroxides. The results show that such factors as pH, ionic strength, quantity, Hg(Ⅱ) concentration, grain size, temperature,rotation speed and time exert some influence on adsorption rate, with pH playing the strongest role. In addition, the research indicates for the first time that the adsorption of Hg(Ⅱ) on natural iron-bearing oxides and hydroxides shows plateau isotherms instead of Langmuir and Freundlich isotherms, in accord with the isotherm of stepwise ion/coordination particle exchange.

Abstract:The Cd2+ -bearing solutions prepared in laboratory were treated by natural cryptomelane. According to the experimental results, it is at least 2 days before the process can reach balance; the disposal quantities become larger when the radius of the cryptomelane becomes smaller; if the concentrations are not too high, the disposal quantities of Cd2+ by unit mass of mineral powder will increase with the increasing concentration; pH value is the dominant factor governing the disposal quantities of Cd2+ : the quantity of the treated Cd2+ gets down until reaching the minimum when the pH value is lower than 3, and then goes up and arrives at the maximum until pH value is near 11. The negative ions in the solution affect the quantity through complexation with Cd2+ ions. Within the whole range of concentration, the disposal quantities curve can be fitted well by Langmuir isotherms, with the maximum being 5.54 mg/g. The treatment of the ions by the mineral powder is accompanied by the dissolution of the Mn2+ and K + ions. When the cinders of the powder are leached, they still hold most of the Cd2+ (79.82%) separated from the solution.

Abstract:In order to confirm that products of phenol degradation by natural cryptomelane are innoxious, the authors conducted qualitative analysis of organic products and determined TOC of solution, thus detecting the oxidation routes of phenol. The oxidation mechanism of phenol is inferred on the basis of some experimental phenomena. The results are as follows: first, TOC can be reduced by 88.7% after the oxidation of phenol wastewater for eight hours; second, oxygen in Mn(Ⅳ)—O bond in cryptomelane changes into O·after it donates two electrons to Mn(Ⅳ), and then O·oxidizes phenol and its resultants are adsorbed on minerals. Some important intermediates detected in GC-MS experiments are p-benzoquinone, 2-benzofuranol and 4,4 '-diol-1,1 '-biphenyl, and the reaction routes of phenol oxidation are deduced by these intermediates.

Abstract:Printing and dyeing wastewater (PDW) decolorization by natural cryptomelane was studied in aqueous and acidified suspensions on the basis of the oxidation and deoxidization property of natural cryptomelane. The results show that the reaction rate increases with the decrease of pH and grain size and the increase of mineral quantity and time,and the addition of sodium nitrate is in favor of the decolorization of dyes whereas the phosphate inhibits the reaction. 10 kinds of PDW were treated in the experiment, the decolorization rate of most of dyes can be up to 95%, with the lowest one above 84%. The PDW of Huafeng Plant after treatment reaches level I discharge criterion of industrial wastewater. Based on the experiment on solubility of natural cryptomelane, Mn(Ⅳ) can be deoxidized into Mn(Ⅱ), it is tentatively proposed that the possible reaction scheme is the xidation-deoxidization reaction.

Abstract:In this paper, the saturation adsorption of machine oil on the exfoliated graphite at different temperatures was studied, and the adsorption effect of machine oil was observed by static adsorption and dynamic filtration. The results show that the saturation adsorption capacity is related to the expansion volume of exfoliated graphite and the oil temperature. The largest adsorption quantity can reach 80.7 g/g. When the oil content is lower than the saturation adsorption, the concentration of remnant oil after static adsorption is related to the expansion volume and original concentration, being generally lower than 50 mg/L. The concentration of remnant oil in water is zero after the first dynamic filtration, whereas the de_adsorption of the oil in the exfoliated graphite can not be realized even after many times of filtration. In conclusion, the exfoliated graphite has a super_adsorption capacity for machine oil, and the floating machine oil can be effectively cleared away by static or dynamic filtration.

Abstract:The adsorption kinetic processes of methylene blue, crystal violet and methyl green from aqueous solution on activated sepiolite were studied, and the effects of concentration and temperature on adsorption were analyzed. FTIR measurement was performed on sepiolite and sepiolite_dyes. The results show that the concentration has greater influence on the adsorption behavior than the temperature. Due to its small molecular dimensions, methylene blue can migrate into the tunnels of sepiolite, while the more voluminous dyes such as crystal violet and methyl green are mainly adsorbed on the external surface of sepiolite. Monovalent organic cations can be adsorbed on the neutral sites of sepiolite and form neutral or monovalently charged complexes.

Abstract:In this paper, the polluted sediment capping technique was used to control the eutrophic water from the Dianchi Lake on the basis of field simulating experiments. The capping experimental materials include natural laterite and additives such as coal ash and powder of lime, which are all cheap geological materials. An analysis of the 125-day monitoring data consisting of the physical and chemistry indexes showed the eutrophication of the experimental barrel water and the interrelated water, it is held that the application of natural mineral materials to controlling the water eutrophication through the reduction of the internal pollutant loading of the polluted sediments in the eutrophic lake or reservoir is an effective technique, and that the laterite is an efficient superstratum for separating the polluted sediments from the upper eutrophic water. It is also considered that laterite plays an important role in reducing the release of the total phosphorus and the total nitrogen and increasing the controlling efficiency of the breeding and floating of the phytoplanktons such as alga, algae cells and algae embryos by means of the addition of the additives like coal ash and powder of lime. The algae may be eventually eliminated from the water. The technique can provide a new train of thought for the remedy of the eutrophic water in the Dianchi Lake and similar lakes.

Abstract:According to the characteristics of serpentine in such aspects as its chemical composition, crystal structure and chemical bond, the authors have divided the activated atom group in serpentine into five classes, i.e. unsaturated Si—O—Si,O—Si—O,OH—Mg—OH(O),OH-,and O—H—O. With these unsaturated chemical bonds, serpentine is of high chemical activity and biological activity. Chrysotile can easily enter the cell of organism because of its nature of one-dimensional nanometer_sized silk. When chrysotiles act with body fluid, they release OH-,Mg2+,SiO2,Ni2+, O and some other components, forming an alkaline_oxidizing environment in the body, which seriously interferes with the role of cells, and results in various diseases of the organism.

Abstract:The changeable cations and the exchange capacities of industry vermiculite samples from the Weli Mine of Xinjiang, the Lingbao Mine of Henan Province and the Tongguan Mine of Shaanxi Province have been studied. It is found that the changeable cations in phlogopite_vermiculite samples from the Weli Mine are mainly Na + and Ca 2+ , followed in importance by Mg 2+ , K +, Ba 2+ and Sr 2+ , while the changeable cations in phlogopite_vermiculite samples from the Tongguan Mine are mainly Mg 2+ and Ca 2+ , with Na + and K + possessing the second place. The cation exchange capacities of phlogopite_vermiculite and chlorite_vermiculite increase with the content of vermiculite crystal layer in interstratified structure. The cation exchange capacities are commonly between 56.92 mmol/100 g and 98.95 mmol/100 g, only half of the maximal value of cation exchange capacity of vermiculite. The cation exchange capacities of phlogopite_vermiculite are negatively related to the content of K 2O and positively related to the content of Na 2O and CaO.

Abstract:In this paper, the contact angles between common minerals and water, n_heptane and n_butanol are reported. Seven common minerals, i.e., quartz, biotite, fluorite, pyrite, calcite, microcline and perthite, were polished and measured, and the surface free energies were calculated based on the Young's Equation. The results indicate that most of the crystalline planes are partially wetted by water and fully wetted by n-heptane and n_butanol. Furthermore, the heterogeneity between different crystalline planes is found, which could be attributed to the distinctive density of atoms of different elements as shown from the crystalline lattices. The data obtained and the viewpoint held in this paper will be helpful to understanding the interface process between the mineral and the liquid phase.

Abstract:The suspensions of ultrafine tourmaline powder in water and n_butanol were prepared by grinding. Ultrafine tourmaline powder was prepared by drying the suspensions through direct heating and azeotropic distillation, according to the properties that water may form azeotrope with n_butanol. TEM shows that drying by direct heating might result in hard aggregation of the tourmaline powder, while hard aggregation might be avoided by azeotropic distillation. Raman spectroscopy reveals that there are O_H and C_H on the surfaces of the tourmaline powder obtained by azeotropic distillation, which indicates that butoxy is chemically adsorbed on the surfaces of tourmaline particles, but not adsorbed on those formed by direct drying. X_ray powder diffraction shows that the intensity of diffraction peaks decreases after grinding. There is no damage to the tourmaline crystal lattice in the process of direct heating, azeotropic distillation, or ultrafine grinding. Therefore, butoxy in n_butanol can be adsorbed chemically on the surfaces of the tourmaline particles in the process of azeotropic distillation, which can effectively prevent the formation of liquid_bridge between the particles of tourmaline and avoid the hard aggregation in the drying process.

Abstract:As a kind of special industrial raw materials, porous minerals and rocks have been playing more and more important roles in the environmental remediation materials and are arousing great interest among mineralogists. Based on the dimensions, structures, shapes of the pores and the surface components of the porous minerals and rocks, this paper has summed up characteristics of typical porous minerals and rocks such as attapulgite, montmorillonite, sepiolite, zeolite and diatomite, and evaluated their application as filters, sorbents, ion exchangers and catalysts in environmental engineering.

Abstract:As a traditional industrial mineral, chrysotile is a kind of one_dimensional nano_tube material with the unique tubular structure formed by curled unit layers. It has many good properties, such as well mechanical strength, resistance to heat, insulation, and high face chemical activity and bio_activity. Its activities are mainly derived from the face unsaturated bonds, face energy carried by enormous specific surface area inherent in nano_crystals, and additional internal energy and face energy produced by lattice winding due to the curly structure. With its good physical and chemical properties, chrysotile will surely have broad applying prospects in the new nano_material field. Its high face activities can on the one hand be utilized to control environmental pollution, but on the other hand bring about fatal threat to human beings by resulting in asbestos lung and cancers. With the aim of safe utilization of the fine properties of chrysotile, it is important to study thoroughly the dust pollution and disease_causing mechanism of chrysotile and carry out effective face modification so as to reduce or remove its cytotoxicity. In addition, factories, mines and other enterprises dealing with mining, separating and processing of chrysotile should monitor the dust pollution and improve the protection means for workers.

Abstract:In this paper, the researches on the substitutions of Ca_polyhedral, P_tetrahedral and channel positions in apatite structure are reviewed, the structural sites, substitution forms and mechanism of isomorphic ions are discussed, and the influence of the substitution of this mineral upon the environmental mineralogy is briefly described.

Abstract:A number of recent papers have dealt with such properties of clay minerals as their compositions, assemblages, contents and crystallinities,which can reflect the periodic climate changes of the mineral sources and help to reconstruct paleoclimate. Due to the sensitivity of the clay minerals, however, any climatic influence upon the compositions of clay minerals can be easily covered up by extra-climatic events such as source rock,sedimentary environment,and diagenesis. Therefore, both climatic effects and extra-climatic influence should be considered when the clay minerals are used to reconstruct paleoclimate.

Abstract:individual mineral particulates in PM10 samples, collected over different months in Beijing, were analyzed by SEM/EDX. The results show that mineral particulates in PM 10 over Beijing are complex and heterogeneous. Some 38 mineral species in PM10 were identified, in which clay minerals occupy the dominant position, accounting for 30.1%. The illite/smectite mixed layers seem to be the most common species in clay minerals. Quartz, calcite, composite particles and carbonaceous particles make up 13.5%, 10.9%, 11.95% and 10.31% respectively. Gypsum, feldspar and dolomite are below 10% on average. Fluorite, apatite, halite, barite and zinc chlorides were recognized firstly in Beijing PM10 . Sulfuration occurs on the surface of most mineral particles, especially in summer, suggesting a relatively extensive atmospheric reaction over Beijing in summer.

Abstract:Atmospheric particle settlings (APSs) are deposited from aerosols and have complex mineral components and chemical composition as well as varied origins. The TEM investigation of long-term atmospheric particle settlings can provide information concerning phase components, morphology and origins of APSs as well as their symbols. According to the investigation in Hefei area, the dust blowing from the surface with clay minerals as the symbol possesses the first importance, the autogenous aerosol related to SO2, CO2 and NO X with gypsum, carbonate, and other soluble salts as the symbols occupies the second importance, the dust from automobiles with nanometer carbon balls as the symbol is the third in importance, and the dust from combustion of coal with silicate microbeads as the symbol is the last in importance. The authors have also found nanometer calcite biomineralization inside bacteria and nanometer apatite at the surface of minerals due to biomineralization outside bacteria and interaction between bacteria and minerals. The TEM investigation provides not only information about origins of aerosols in Hefei area but also effective methods and symbols for determining APSs.

Abstract:Mineral-humus interactions are key interfacial processes for the environmental substances in soils, aquatic sediments and suspended particulates. The movement, transport and fate of either nutrient elements of nitrogen and phosphorus or heavy metals as well as toxic organic chemicals in the environment are regulated by the surface reactivity and movement of minerals, humic substances and their complexes. The research on the interface interactions of mineralhumus systems is a prospective field. The major objective in this study lies in describing such structural features of particulates as the layered structure and the micro-conformation and their relations with the reactivity of particulates and revealing the mechanism of mineral-humus interactions in soil and water environments. In this paper, the advances made in this field are reviewed and its future trend is predicted.

Abstract:The Linchong tailings reservoir of the Fenghuangshan mine in Tongling of Anhui Province is one of quite a few tailings reservoirs there. In this paper, it was selected to study the distribution and migration of heavy metal elements. According to the changes of the heavy metal contents of the tailings reservoir and a comparison of the heavy metal contents between the tailings, the related soils, the river system sediments and the plants, the authors have found out the regularities governing the space distribution and migration of the heavy metal elements, discussed the environmental effects and latent harmfulness of the tailings, and pointed out the correct means for developing and utilizing the land in the mine tailings reservoir.

Abstract:Researches on the ecological geochemical surveying method in alluvial plains of China show that the contents and characteristic distribution of elements are determined by inherited mineral assemblages in soil. The differences in regional geochemical backgrounds of elements and in their contents at different depths are shown evidently by minerals and mineral assemblages. The mineral assemblage in soil directly determines the content of elements. Therefore, the application of the mineral assemblage in soil to determination of the initial values of major elements and microelements is of great significance. The result can determine the cause of geochemical anomalies and distinguish the types of geochemical anomalies.

Abstract:Organic-inorganic (minerals) controlled release material was used to modify urea and develop two new kinds of controlled release N fertilizers—modified urea. The result of potted plant shows that two modified kinds of urea are better than the normal urea under the condition of equal weight. XRD and IR were also used to analyze the crystal structure of the new kinds of modified urea, and found that their crystal structure changed greatly. It is the crystal structure change that increases the stability of modified urea.In this way we can raise the fertilizer efficiency and increase the utilization ratio of N.

Abstract:In this paper, the chemical and mineral composition of the coal gangue from Huangshi City, Hubei Province, was systemically analyzed, and its quality and grade were evaluated. Experiments with different proportions of coal gangues as raw materials were carried out. The measurement and analysis of water absorption rate and rupture modulus of the porcelain bodies were made under the conditions of different dosages and sintering temperatures. The integrated analysis of performance indexes shows that the coal gangue of iron_rich sandstone from Huangshi City can be used to produce porcelain brick, with the quality consistent with the corresponding national quality standards on water absorption rate and rupture modulus of the porcelain bodies. The content of coal gangue in the porcelain brick can be as high as 80%. The water absorption rate of the porcelain bodies is lower than 0.3%, their rupture modulus is higher than 35 MPa, and their colors change from light red through dark red to purple brown.

Abstract:Mineral composition and microstructure of fly ash-high cementitious materials were studied by such means as chemical analysis, XRD and SEM. The results show that the mineral composition is mainly 3Al2O3·2SiO2and silica-alumina gelled mineral. Fly ash_high cementitious materials are characterized by the structure of numerous big holes. The mineral composition and microstructure of these materials are quite different from those of cement concrete. The content of fly ash and the curing time affect directly the quantity of hydrated product. When the content is above 20%, the materials entirely react with the consolidating agent and form porous solid bodies.

Abstract:Fly ash was used as the main material to prepare mineral polymer in this study. The potassium_distilled waste residue obtained from potassium_rich slate was used as the raw material to replace sodium (potassium) silicate, calcined kaolin, sodium (potassium) hydroxide which are frequently used abroad to prepare mineral polymer. In this way, mineral polymer was prepared. The optimal technical parameters were determined by the orthogonal experiments: the weight proportions of calcined kaolin, waste residue and sodium hydroxide are about 10%~15%, 35% and 5%~6%, respectively. Compressive strengths of the representative mineral polymer samples were tested up to 40~50 MPa after 7d's solidification. Tests show that the acid and alkali resistances of the samples are 99.99% and 100%, respectively, and their density, contractility, thermal conductivity and mean rigidity are 1.77~1.88 g/cm3, 0.13%~0.28%, 0.48~0.51 W/m·K and 3.43, respectively. XRD analysis shows that the matrix phase is amorphous.SEM photograph analysis shows that the floccule matrix phase is combined closely with the glass phase of the fly ash, which provides a good structural basis for the samples. The cost of mineral polymer is low, and it can improve the environment by the utilization of offal-like fly ash.

Abstract:新世纪的首届国际矿物学大会于 2 0 0 2年 9月在英国爱丁堡举行。继上届首次增设环境矿物学专题后 ,环境矿物学问题成为本届大会的一个重要论题 ,提交论文的数量和质量都有了明显提高。会议收录了 2 3个国家 (上届 14个国家 )的环境矿物学方面论文 91篇 (上届 32篇 ) ,提交论文较多的国家有英国 (2 3篇 )、美国、意大利 (各 9篇 )、日本 (7篇 )和中国(5篇 )等。论文主要分为 4个主题 ,分别是矿物与微生物的相互作用 (6篇 )、生物矿化作用与有机成因矿物 (18篇 )、环境矿物与人类健康 (2 8篇 )及矿物学和污染地球化学 (39篇 )。1　矿物与微生…