Pervaporation performance and characterization of hydrophilic ZSM-5 zeolite membranes for high inorganic acid and inorganic salts

The hydrophilic ZSM-5 zeolite membranes are applied to separate the inorganic acid solutions and inorganic acid/inorganic salt mixtures by pervaporation,and the membrane presents good stability,dehydration,and desalination performance.Influences of inorganic acid type(H_(2)SO_(4),H_(3)PO_(4),HNO_(3),and HCl),H_(2)SO_(4)concentration(1-6 mol·L^(-1)),test temperature(60-90℃)and inorganic acid/inorganic salt type(2 mol·L^(-1)H_(2)SO_(4)and sulfate,2 mol·L^(-1)H3PO4 and phosphate)on the pervaporation performance are investigated in this work.Either for concentrating 3%(mass)H_(2)SO_(4)solution or consecutive dehydrating 20%(mass)H_(2)SO_(4)solution,the hydrophilic ZSM-5 zeolite membrane has a good dehydration performance and stability.Even though the H_(2)SO_(4)concentration and test temperature are increased to 6 M and 90℃,only H_(2)O molecules could pass through the membrane and pH value of the permeation is kept neutral.Besides,the membrane has good dehydration and desalination performance for H_(2)SO_(4)/sulfates and H_(3)PO_(4)/phosphate mixtures,and the rejection of natrium salt,molysite,and magnesium is almost 100%.

SYNTHESIS OF MESOPOROUS TiO_2 MATERIALS WITH HIGH SPECIFIC AREA USING INORGANIC ACIDS AS CATALYSTS

This paper presents a synthesis process for preparing mesoporous titaniumdioxide materials in the absence of any templates and using inorganic acids as catalysts. Tetrabutyltitanate was used as the precursor at ambient temperature, and four different inorganic acids,i.e., hydrochloric, nitric, sulfuric and phosphoric, were used as catalysts. The as-preparedmesoporous TiO_2 materials were characterized by SEM, XRD and nitrogen adsorption/desorptionmeasurements. The influences of different inorganic acids on the properties of TiO_2 were discussedand compared in details. Experiments showed that the inorganic acids have significant effects on thesurface area, pore volume, pore size, and pore size distribution of the products. The mesoporousTiO_2 materials catalyzed by phosphoric acid exhibited the largest specific surface area and largestpore volume with narrow pore size distribution. Vacuum and infrared drying methods tested in theprocess were found to have subtle impact on the structure of the TiO_2 materials prepared.

Preparation of 3D micro/nanostructured CeO2： Influence of organic/inorganic acids

CeO2 is an important porous material with a wide range of applications in the abatement of volatile organic compounds （VOCs）. In this paper, we prepared a series of novel three-dimensional （3D） micro/nanostructured CeO2 materials via a solvothermal method. Organic acid-assisted synthesis and inorganic acid post-treatment were used to adjust the Ce02 microstructures. The size of the 3D micro/nanostructures could be controlled in the range from 180nm to 1.5 μm and the surface morphology changed from rough to smooth with the use of different organic acids. The CeO2 synthesized with acetic acid featured a hierarchical porosity and showed good performance for toluene catalytic combustion： a T50 of 187 ℃ and a T90 of 195 ℃. Moreover, the crystallite size, textural properties, and surface chemical states could be tuned by inorganic acid modification. After treatment with HNO3, the modified CeO2 materials exhibited improved catalytic activity, with a T50 of-175 ℃ and a T90 of -187 ℃. We concluded that the toluene combustion activity is related to the porosity and the amount of surface active oxygen of the CeO2. Both these features can be tuned by the co-work of organic and inorganic acids.

Two Novel {Ti_(6)P_(2)} Clusters Decorated with Inorganic Acids

Two inorganic acids decorating titanium-oxo clusters (PTCs),Ti_6O_4(O~iPr)_(10)(O_(3)P-Phen)_(2)(NO_(3))_(2)(PTC-251) and Ti_6O_4(O~iPr)_(10)(O_(3)P-Phen)_(2)(HSO_4)_(2) (PTC-252)(H_(2)O_(3)P-Phen=phenylphosphinic acid) have been synthesized under solvothermal conditions.As a result of the labile coordination sites of the{Ti_6P_(2)}unit,nitrite and sulfate adopt different capping mode.Besides,they also present different space packing.The photocatalytic H_(2)evolution activities of these obtained PTCs have been studied,with sulfate decorating PTC-252 presenting a maximum H_(2) production rate up to 110.95μmol·g^(-1)·h^(-1).

Effects of Inorganic Acids on Free Phenol Level in Liquefaction Products of Particleboard

In various temperatures, the effects of inorganic acids on the free phenol level in liquefaction products were investigated. In this paper, the free phenol level was used as an indicator to evaluate liquefaction efficiency. Results showed that sulfuric acid was the best among the 4 acids. Under the condition of reaction temperature 150 ~C, reaction time 1.5 h, liquefaction ratio （liquid ! particleboard） 4 and content of sulfuric acid 6%, the free phenol level in the liquefaction products of waste particleboard is 36.95%, and that of original particleboard is 24.27%.

INHIBITIVE ACTION OF INORGANIC COMPOUND ON CORROSION OF ALUMINIUM IN HYDROCHLORIC ACID

The inhibitive action of CaSO_4 towards corrosion of aluminium in 1 mol/L HCl has been inveetigated by using fluorometrio and weight loss techniques.The results show that the inhibitor exhibits an outstanding function of inhibition,especially at higher tempe- ratures,and it was found to be predomiantly of cathodic rate control.Ths mechanism of inhibition and the effect of CdSO_4 on the corrosion kinetics are also discussed.

Does acid pickling of Mg-Ca alloy enhance biomineralization?

The mechanical and physical properties of biodegradable magnesium(Mg)alloys make them suitable for temporary orthopaedic implants.The success of these alloys depends on their performance in the physiological environment.In the present work,surface modification of Mg-Ca binary alloy by acid pickling for better biomineralization and controlled biodegradation is explored.The corrosion rates of nitric and phosphoric acid treated samples were analysed by conducting electrochemical corrosion tests.In vitro degradation behaviour was studied using immersion test in simulated body fluid(SBF).The sample surfaces were characterized using scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).It is seen that acid pickling leads to significant improvement in biomineralization and develop in situ calcium phosphate(Ca P)coating on the sample surfaces.In addition,the treated samples recorded a reduced degradation rate in the SBF compared to untreated samples.Thus,acid pickling is suggested as an effective surface treatment method to tailor the biomineralization and degradation behaviour of the Mg-Ca alloy in the physiological environment.

Stable Electron Spin Pan on Aromatic Oxalic Acid Radical

The stability of organic radicals in ambient condition is important for their practical application.During the development of organic radical chemistry,the electron-withdrawing and steric hindrance groups are usually introduced to improve the stability of radicals via reducing the reactivity of radicals with oxygen in air.Herein,the electron-withdrawing carbonyl groups are introduced to construct a planar aromatic oxalic acid radical(IDF-Og)with two-dimensional electron spin pan structure.Interestingly,IDF-Og exhibited a low optical bandgap of 0.91 eV in film,however,the multiple quinone resonance structures between electron-withdrawing ketone and phenol radicals contribute to the high stability of open-shell radical IDF-Og without protection of large steric hindrance groups.Under the irradiation of 808 nm(1.2 W.cm^(-2)),IDF-Og reaches 147 c in powder state.This work provides an efficient synthesis route for the open-shell electron spin pan system,which is different from the famous fullerene,carbon nanotube and graphene.The electron spin pan can be extended to spin tube or spin sphere system based on the design strategy of aromatic inorganic acid radicals in future.

Multiple transformation pathways of p-arsanilic acid to inorganic arsenic species in water during UV disinfection

p-Arsanilic acid（p-ASA） is widely used in China as livestock and poultry feed additive for promoting animal growth.The use of organoarsenics poses a potential threat to the environment because it is mostly excreted by animals in its original form and can be transformed by UV–Vis light excitation.This work examined the initial rate and efficiency of p-ASA phototransformation under UV-C disinfection lamp.Several factors influencing p-ASA phototransformation,namely,p H,initial concentration,temperature,as well as the presence of Na Cl,NH4＋,and humic acid,were investigated.Quenching experiments and LC–MS were performed to investigate the mechanism of p-ASA phototransformation.Results show that p-ASA was decomposed to inorganic arsenic（including As（Ⅲ） and As（V））and aromatic products by UV-C light through direct photolysis and indirect oxidation.The oxidation efficency of p-ASA by direct photosis was about 32%,and those by HOU and1O2 were 19% and 49%,respectively.Cleavage of the arsenic–benzene bond through direct photolysis,HOU oxidation or1O2 oxidation results in simultaneous formation of inorganic As（Ⅲ）,As（IV）,and As（V）.Inorganic As（Ⅲ） is oxidized to As（IV） and then to As（V） by1O2 or HOU.As（IV） can undergo dismutation or simply react with oxygen to produce As（V） as well.Reactions of the organic moieties of p-ASA produce aniline,aminophenol and azobenzene derivatives as main products.The photoconvertible property of p-ASA implies that UV disinfection of wastewaters from poultry and swine farms containing p-ASA poses a potential threat to the ecosystem,especially agricultural environments.

Experimental on C50 Ultra-high-early Strength Concrete

In this paper,C50 ultra-high-early-strength concrete was prepared with rapid-harden sulphoaluminate cement,alkali carbonate early strength agent,inorganic tribasic acid retarder and polycarboxylate water reducing agent. The properties testing results of C50 ultra-high-early-strength concrete indicated that the compressive strength at 12 h exceeded 37 MPa and at 3 d exceeded 59 MPa. Compared to the C50 ordinary reference concrete,the durability of C50 ultra-high-early strength concrete was investigated. The results indicated that C50 ultra-high-early-strength concrete had the same chloride ion permeability resistance,carbonization resistance and abrasion resistance to the C50 ordinary concrete. As to the sulfate resistance,the ultra-high-early-strength concrete was much better than the ordinary concrete.