响石

响石,以前在玩石界是指像灵壁石那样敲之即响的声石。主要是CaCO_3类岩石,其中SiO_2含量较高,声响清脆悦耳。而这里所说的响石则是石中有石,更是妙趣横生。响石的学名为结核锰。

Acid mine drainage activation mechanism on lime-depressed pyrite flotation from copper sulfide ore

The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was recovered.The effect of AMD on lime-depressed pyrite flotation was investigated by a series of laboratory flotation tests and surface analytical techniques.Flotation test results indicated that AMD could effectively activate the pyrite flotation with a sodium butyl xanthate(SBX)collector,and a high-quality sulfur concentrate was obtained.Pulp ion concentration analysis results indicated that AMD facilitated desorption of Ca^(2+)and adsorption of Cu^(2+)on the depressed-pyrite surface.Adsorption measurements and contact angle analysis results confirmed that adding AMD improved the adsorption amount of SBX collector on the pyrite surface and increased the contact angle by 31°.Results of Raman spectroscopy and X-ray photoelectron spectroscopy analysis indicated that AMD treatment promoted the formation of hydrophobic species(S^(0) hydrophobic entity and copper sulfides)and the removal of hydrophilic calcium and iron species on the pyrite surface,which reinforced the adsorption of collector.The findings of the present research provide important theoretical basis and technical support for a cleaner production of copper sulfide ores.

Effect of degree of substitution of carboxymethyl starch on diaspore depression in reverse flotation

Carboxymethyl starchs（CMS） with low and high degrees of substitution（CMSL and CMSH in short,respectively） were employed as depressants of diaspore in cationic reverse flotation using dodecylamine（DDA） as collector.The effect of degree of substitution of CMS on its depression performance was examined and the interaction mode and behavior were investigated in a comparative manner.Micro-flotation test showed that CMSL exhibited better performance in depressing diaspore than CMSH in a broad pH range.The adsorption of CMS on diaspore was studied by adsorption test,zeta potential measurement,and atomic force microscopy.It was found that CMSH corresponds to lower adsorption amount,thinner adsorption layer,and more negative charge than CMSL,resulting from the more chelating sites brought by the high degree of substitution.The surface tension measurement and DDA adsorption test further revealed that CMSL/DDA system gives a better depressing performance benefiting from the trapping effect by enveloping some DDA molecules inside the loop chains,while CMSH/DDA system is likely considered a quasi-surfactant.

Flotation and adsorption of quaternary ammonium cationic collectors on diaspore and kaolinite

The flotation and adsorption behaviors of dodecyltrimethylammonium chloride（DTAC） and cetyltrimethylammonium chloride（CTAC） on diaspore and kaolinite were studied.Solution depletion methods were used to determine adsorption isotherms.Fluorescence probe test along with Zeta potential measurement was also conducted for further investigation into the adsorption of quaternary amines at the mineral-water interface.The results show that the flotation recovery of kaolinite decreases with an increase in pH when DTAC and CTAC are used as collectors,while diaspore is on the contrary.As the carbon chain length of the collectors increases,the flotation recoveries of minerals increase.However,the increment rate of kaolinite is significantly lower than that of diaspore.In the low surfactant concentration range,the cationic surfactants adsorb readily on diaspore surfaces just due to electrostatic interactions.As for kaolinite surfaces,ion exchange process also exists.With a further increase in surfactant concentration,the adsorption was ascribed to the hydrophobic association of chain-chain interactions.Micro-polarity of mineral surfaces study shows that CTAC has a better hydrophobic characteristic than DTAC.Larger aggregates are formed with CTAC on diaspore than on kaolinite in the same solution concentration.The results also indicate that the chain length of cationic surfactants has a greater influence on the adsorption of diaspore than on kaolinite,which is consistent with the flotation result.

A novel collector RL for flotation of bauxite

The flotation properties of single minerals such as diaspore, kaolinite and pyrophllite in bauxites were investigated using RL as collector. The effects of regulators and unavoidable ions on flotation were studied. Based on the results of single minerals flotation, the separation experiments of mixed minerals and bauxite ore were carried out. The results of closed circuit test on the ore show that, using RL as collector, Na 2CO 3 and (NaPO 3) 6 as modifiers, the grade of Al 2O 3 and SiO 2 are respectively 70.74% and 6.37% in concentrate (Al/Si 11.11), and the recovery of Al 2O 3 can reach 90.52%.

Effects of different factors during the de-silication of diaspore by direct flotation

Most of the bauxite resources in China are kaolinite-diaspore bauxite of middle to low grade, with a fine dissemination, and are difficultly separated. Direct flotation de-silication has been shown to be an effec- tive method for de-silication of diaspore. In this study the effect of different factors, including pulp tem- perature, density, pH value, depressant, and collector dosage, on direct flotation of diaspore were investigated by laboratory experiments. The optimum conditions were identified and the flotation perfor- mance was improved. The results show that under optimum conditions （a pulp temperature around 40℃, a pulp density from 30% to 33g, a pH value from 9.0 to 10.0, an air flow rate of 0.5 m3/（m2 rain）, a dispersant level from 35 to 70 g/t, and a collector level around 1000 g/t） an AI/Si ratio of 6.97 is obtained starting from an initial Al/Si ratio of about 4.71. The recovery of A1203 under these conditions was 86.94%.

Effects of sodium hexmetaphosphate on flotation separation of diaspore and kaolinite

In order to offer high grade concentrate to produce alumina by Bayer, the reverse-flotation technology of bauxite was investigated. The results show that sodium hexmetaphosphate has different depression on the flotation of diaspore and kaolinite. The recoveries of diaspore decrease markedly with the increase of the concentration of sodium hexmetaphosphate with dodecyl-amine as collector. Fourier transform infrared spectra indicate that the absorbance band 875cm -1 of the asymmetric stretching vibration of bridge oxygen P—O—P shifts to 880cm -1 , and the 1264cm -1 of the asymmetric stretching vibration of the bridge PO2 shifts to 1267cm -1 in the diaspore’s spectra. This demonstrates that sodium hexmetaphosphate interacts through bridging PO2 groups with the Al atoms exposed on the diaspore and kaolinite surfaces to form P—O—Al bond. Adsorption measurements also testify that sodium hexmetaphosphate adsorbs easily on the surface of diaspore. The adsorption density of PO-3 on the surface of diaspore is about 4.7×10 -6 mol/m2, while that on the kaolinite is only about 3.5×10 -7 mol/m2 when pH value is 6.

Flotation behavior and adsorption mechanism of salicylhydroxamic acid in artificial mineral anosovite

Flotation is often employed to separate valuable natural minerals and gangue minerals.However,few studies have been conducted on artificial mineral flotation.Anosovite,the primary mineral in titanium slag,is a typical artificial mineral that can be enriched by flotation.In the present work,flotation behavior and adsorption mechanism of anosovite in salicylhydroxamic acid(SHA)solution were studied.The influence of pH and SHA dosage on anosovite flotability was investigated.Micro-flotation test results show that a pH range of 7–8.5 is available for SHA to collect anosovite.A maximum recovery of 93.26%can be obtained with SHA dosage of only 4×10.5 mol/L.In addition,TOC,zeta potential,FTIR,SEM-EDS,and XPS analyses were used to study the adsorption mechanism.Results demonstrated that SHA adsorption is governed by chemisorption.XPS studies further suggested that chemical adsorption occurred at the Ti sites on the anosovite surface.

Hydrophobic flocculation flotation of rutile fines in presence of styryl phosphonic acid

The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid（SPA） was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based particle size analysis, adsorption measurements and DLVO theory. The flotation tests indicated that rutile fines could be flocculated by SPA, and pH, shear force（stirring speed） and stirring time played significant roles in flocculation. The isoelectric point（IEP） and zeta-potential in whole range all moved to negative values as SPA was added according to the results from zeta-potential measurement. It was demonstrated that the primary reason for above was chemical adsorption. The laser-based particle size results showed the particle size at a stirring speed of 1800 r/min and 1000 mg/L SPA was the largest in all experiments. Furthermore, using the optical microscope observation and flotation tests, it was important for flotation of rutile fines to produce the flocculant. In the light of above-mentioned facts, floc flotation of rutile fines could be induced in the form of chemical adsorption by SPA to increase particle size. The data calculated from DLVO theory also indicated that chemical adsorption was the main reason for the formation of flocculant.

Flotation of kaolinite and diaspore with hexadecyl dimethyl benzyl ammonium chloride

Tertiary amine was synthesized from fatty amine and formaldehyde. And then the synthesized tertiary amine was used to react with benzyl chloride to synthesize hexadecyl dimethyl benzyl ammonium chloride (1627) at ambient pressure. Using the synthesized 1627 as collector,the flotation properties of diaspore and kaolinite were investigated by single mineral and mixed mineral test. The flotation mechanism of diaspore,kaolinite and 1627 was discussed based on FTIR spectra. The results show that the mass ratio of aluminum to silicate achieves 15.02 and the recovery of alumina in concentrate is 43.07% using 1627 as a collector. The 1627 is found to be a more effective and a promising collector for reverse flotation to remove aluminum-silicate minerals from bauxite.

Hydrophobic intensification flotation:Comparison of collector containing two minerophilic groups with conventional collectors

The surface hydrophobization and flotation of a xanthate−hydroxamate collector toward copper oxide mineral were compared with the combined collectors of xanthate and hydroxamate through water contact angle(WCA)and micro-flotation experiments.The results showed that S-[(2-hydroxyamino)-2-oxoethyl]-O-octyl-dithiocarbonate ester(HAOODE)exhibited stronger hydrophobization and better flotation performance to malachite(Cu2(OH)2CO3)than octyl-hydroxamic acid(OHA)and its combination with S-allyl-O-ethyl xanthate ester(AEXE).To understand the hydrophobic intensification mechanism of HAOODE to malachite,zeta potential,atomic force microscopy(AFM)and XPS measurements were carried out.The results recommended that malachite chemisorbed HAOODE to form Cu—HAOODE complexes in which the hydroxamate—(O,O)—Cu and—O—C(—S—Cu)—S—configurations co-existed.The co-adsorption of HAOODE’s hetero-difunctional groups was more stable than the single-functionalgroup adsorption of OHA and AEXE,which produced the“loop”structure and intensified the self-assembly alignment of HAOODE on malachite surfaces.In addition,the“h”shape steric orientation of the double hydrophobic groups in HAOODE facilitated stronger hydrophobization toward malachite than the“line”or“V”hydrophobic carbon chains of OHA or AEXE.Thus,HAOODE achieved the preferable flotation recovery of malachite particles in comparison with OHA and AEXE.

Flotation behavior of four dodecyl tertiary amines as collectors of diaspore and kaolinite

The flotation of diaspore and kaolinite by one of a series of tertiary amines（DRN,DEN,DPN and DBN） was investigated.The tertiary amines show better floating recovery for kaolinite compared to diaspore.The maximum recovery D-value is 45%over a pH range from 3 to 8.FT-IR spectra confirm the presence of hydroxyl groups on the surface of kaolinite and diaspore.Zeta potential measurements show that the mineral surfaces are negatively charged over a wide pH range.Ionization of hydroxyl groups mainly accounts for the surface charging mechanism.The adsorption of tertiary amines onto the mineral surface is due mainly to electrostatic effects and the difference in electrostatic effect between a collector and the two minerals can explain the flotation separation.Inductive electronic and steric effects from the substituent groups result in different collecting powers for the four tertiary amines.

浅谈山石盆景石料的选择

制作山石盆景的石料很多,一般分松石和硬石两大类。松石又称上水石,质地疏松,利于吸水,可以栽树种草,加工方便。硬石石料坚硬,天然纹理美观,形态奇特,不吸水,不能点种植物,雕琢加工也较困难。我国各地石料资源种类繁多,可就地取材,创作出具有地方风格的山石盆景。