酸解破乳作用处理高含固率洗毛废水的研究

洗毛废水是一种高浓度有机废水,含固率高,主要成分是羊毛脂、羧酸盐和土杂,由于强极性物质的存在和胶体强的负电性,导致洗毛废水形成稳定的乳化体系。本试验通过加入硫酸改变洗毛废水的有机组成,降低体系的Zeta电位,破坏体系的稳定性,从而使得有机物发生凝聚沉降,达到去除COD的目的。硫酸加入量达到0.2%或以上时对洗毛废水中SS的自然沉降性、絮凝性和极性有很大影响,比阻从远大于9.81×1013m/kg,下降为5.54×1010m/kg,COD去除率达到86.8%,SS去除率达到98%。因此,洗毛废水加酸处理后通过机械脱水,实现固液分离,以降低原废水的色度和大幅降低COD的方式,是可供考虑的处理工艺。

四株解磷菌分泌有机酸与溶解磷酸三钙能力的研究

【目的】研究解磷细菌溶解难溶性磷酸盐及溶磷过程中有机酸的作用。【方法】对P7、P13、P15、P18四株解磷菌进行培养,并对其进行动态观测,用高效液相色谱法测定其有机酸种类及含量,研究其解磷量与有机酸之间的关系。【结果】4株解磷菌溶解磷酸三钙能力有显著差异,解磷能力大小依次是P15>P13>P18>P7。4株解磷菌产生有机酸的含量差异很大,并且同一株解磷菌在培养过程中产生的有机酸种类也会不同。经分析发现有机酸对速效磷的直接影响由强至弱排序依次是:丙酮酸、酒石酸、乳酸、乙酸、草酸。【结论】解磷能力最强的是P15菌株,丙酮酸对溶解磷酸三钙的直接影响系数最大。

Distinct synergetic effects in the ozone enhanced photocatalytic degradation of phenol and oxalic acid with Fe^(3+)/TiO_2 catalyst

In this work. phenol and oxalic acid （OA） degradation in an ozone and photocatalysis integrated process was intensively conducted with Fe3 ＋/TiO2 catalyst. The ferrioxalate complex formed between Fe3＋ and oxalate accelerated the removal of OA in the ozonation, photolysis and photocatalytic ozonation process, for its high reactivity with ozone and UV. Phenol was degraded in ozonation and photolysis with limited TOC removal rates, but much higher TOC removal was achieved in photocatalytic ozonation due to the generation of-OH. The sequence of UV light and ozone in the sequential process also influences the TOC removal, and ozone is very powerful to oxidize intermediates catechol and hydroquinone to maleic acid. Fenton or photo-Fenton reactions only played a small part in Fe3＋/TiO2 catalyzed processes, because Fe＋ was greatly reduced but not regenerated in many cases. The synergetic effect was found to be highly related with the property of the target pollutants. Fe3 ＋/TiO2 catalyzed system showed the highest ability to destroy organics, but the TiO2 catalyzed system showed little higher synergy.

Role of Organic Acids in Desorption of Mercury from Contaminated Soils in Eastern Shandong Province,China

Batch experiments were conducted to study the effects of low-molecular-weight organic acids(LMWOAs) on desorption of Hg from two kinds of soils in the eastern Shandong Province,China.Of all LMWOAs,oxalic and citric acids were chosen as the representatives in this experiment because they are most common in soils.Desorption of Hg increases with the increase of extracting time,until the highest desorption amount at 6-8 h,and then declines.It indicates that timeliness is very important when organic acids are used for phytoremediation in contaminated soils.When the concentrations of organic acids increase from 1.0 mmol/L to 10.0 mmol/L,Hg desorption increases significantly regardless of oxalic or citric acid.Compared with oxalic acid,citric acid is more effective to enhance the desorption of Hg,especially from fluvo-aquic soil.With the increase of initial pH value from 3 to 8,Hg desorption decreases directly in the presence of oxalic acid.However,Hg desorption first decreases,then increases,and eventually decreases again in the presence of citric acid due to the variation of competitive ability between chelating of citric acid and adsorption of soil in different pH values.Citric acid showed greater ability to release Hg from soils than oxalic acid.According to the results of the present study,it is found that the bioavailabilities of heavy metal can be improved with selecting suitable types and concentrations of organic acid amendment and reasonable soil condition.

Effects of Phosphate Adsorption on Adsorption-Desorption and Availability of Cu and Zn Ions in Ultisols and Alfisols

Surface charge, secondary adsorption- desorption and form distribution of Cu2+ and Zn2+ in Ultisols and Alfisols having adsorbed phosphate were studied by potentiometric titration, adsorption equilibrium and sequential extraction method, respectively. The soil surface negative charges increased whereas the amount of positive charges decreased with increase of P adsorbed. The soil secondary adsorption capacity for Cu2+ and Zn2+ was positively significantly correlated with the amount of P adsorbed by the soils, which could be described by the Langmuir equation. The amounts of Cu2+ and Zn2+ desorption from soils were decreased after P adsorption by the soils and the relationship between them was linear. After the soils adsorbed P, form distribution of Cu2+ and Zn2+ in soils changed remarforbly.

Reactive dividing wall column for hydrolysis of methyl acetate:Design and control

Reactive distillation and dividing wall column distillation are two kinds of effective separation technologies,and their integrated configuration,reactive dividing wall column(RDWC),presents attractive advantages.In this study,the rigorous simulation of RDWC for methyl acetate hydrolysis is performed,and sensitivity analysis is conducted to obtain the minimum reboiler duty.Then a comparison is made between the conventional process and RDWC process,and it shows that 20.1% energy savings can be achieved by RDWC process.In addition,the dynamic characteristic of RDWC is studied and an effective control strategy is proposed.The simple PI control scheme with three temperature loops can obtain reasonable control performance and maintain products at desired purities.It is proved that this RDWC process is an energy efficiency alternative with good controllability.

Effects of Organic Anions on Phosphate Adsorption and Desorption from Variable-Charge Clay Minerals and Soil

Effects of citrate and tartrate on phosphate adsorption and desorption from kaolinite, goethite, amorphous Al-oxide and Ultisol were studied. P adsorption was significantly decreased as the concentration of the organic anions increased from 10-5 to 10-1 M. At 0.1 M and pH 7.0, tartrate decreased P adsorption by 27.6% - 50.6% and citrate by 37.9 - 80.4%, depending on the kinds of adsorbent. Little Al and/ or Fe were detected in the equilibrium solutions, even at the highest concentration of the organic anions. Effects of the organic anions on phosphate adsorption follow essentially the competitive adsorption mechanism.The selectivity coefficients for competitive adsorption can be used to compare the effectiveness of different organic anions in reducing P adsorption under given conditions.Phosphate desorption was increased by 3 to 100 times in the presence of 0.001 M citrate or tartrate compared to that in 0.02 M KC1 solution alone. However, for all the soil and clay minerals studied the amount of P desorbed by citrate or tartrate was generally lower than or close to that of isotopically exchangeable P. The effect of organic anions on phosphate desorption arises primarily from ligand exchange.

Purification of chlorogenic acid in Flos Lonicerae with system of polar ordered resins

A system of polar ordered resins was established for purification of chlorogenic acid in Flos Lonicerae. It was composed of three reversed phase resins, AB-8, DM-130 and NKA-9, representative for their gradually increased polarity and selectivity. A method of RP-HPLC was used for determination of chlorogenic acid. And the performance of adsorption and desorption for chlorogenic acid with the system of polar ordered resins was studied. Furthermore, the effects of concentration, pH and flow rate of the adsorbate on adsorption ability were researched. It is indicated that the optimum parameters for chlorogenic acid are as follows: pH 3.5 with a flow rate of 2.5 BVh, the concentration of extract solution at 0.50, 0.40, 0.30 gL respectively for the adsorptive operation twice, and 6.93, 8.66, 10.39 molL ethanol used as gradient eluants. The purity of resulted product of chlorogenic acid arrives 70.20% with yield of 89.79%. With simple procedures, low costs and high purity product, the method of system of polar ordered resins followed by sequential reversed phase separations can be used to refine the chlorogenic acid in the extraction of Flos Lonicerae.

Tannins from Canarium album with potent antioxidant activity

The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF MS） and nuclear magnetic resonance （NMR） analyses The results show the predominance of signals representative of procyanidins and prodelphinidins. In addition, epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed. The tannins were screened for their potential antioxidant activities using l,l-diphenyl-2-picrylhydrazyl （DPPH） and ferric reducing/antioxidant power （FRAP） model systems. Tannins extracted from leaves, twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power.

Pioglitazone attenuates the severity of sodium taurocholate-induced severe acute pancreatitis

AIM： To determine the effect of pioglitazone, a specific peroxisome proliferator-activated receptor-γ, （PPARγ） ligand, on development of severe acute pancreatitis （SAP） and expression of nuclear factor-kappa B （NF-κB） and intercellular adhesion molecule-1 （ICAM-1） in the pancreas. METHODS： Male Sprague-Dawley （SD） rats （160-200 g） were randomly allocated into three groups （n = 18 in each group）： severe acute pancreatitis group, pioglitazone group, sham group. SAP was induced by retrograde infusion of 1 mL/kg body weight 5% sodium taurocholate （STC） into the biliopancreatic duct of male SD rats. Pioglitazone was injected intraperitoneally two hours piror to STC infusion. Blood and ascites were obtained for detecting amylase and ascitic capacity. Pancreatic wet/dry weight ratio, expression of NF-κB and ICAM-1 in pancreatic tissues were detected by immunohistochemical staining. Pancreatic tissue samples were stained with hematoxylin and eosin （HE） for routine optic microscopy. RESULTS： Sham group displayed normal pancreatic structure. SAP group showed diffuse hemorrhage, necrosis and severe edema in focal areas of pancreas. There was obvious adipo-saponification in abdominal cavity. Characteristics such as pancreatic hemorrhage, necrosis, severe edema and adipo-saponification were found in pioglitazone group, but the levels of those injuries were lower in pioglitazone group than those in SAP group. The wet/dry pancreatic weight ratio, ascetic capacity, serum and ascitic activities of anylase in the SAP group were significantly higher than those in the sham group and pioglitazone group respectively （6969.50 ± 1368.99 vs 2104.67 ± 377.16, 3.99 ± 1.22 vs 2.48 ± 0.74, P 〈 0.01 or P 〈 0.05）. According to Kusske criteria, the pancreatic histologic score showed that interstitial edema, inflammatory infiltration, parenchyma necrosis and parenchyma hommorrhage in SAP group significantly differed from those in the sham group and pioglitazone group （7.17 ± 1.83 vs 0.50 ± 0.55, 7.67 ± 0.82 vs 6.83 ± 0.75, P 〈 0.01, P 〈 0.05. The expression of NF-κB and ICAM-1 in sham group was lower than that in SAP group and pioglitazone group （0.50 ± 0.55 vs 33 ± 1.21, P 〈 0.01）. There was a significant difference in the expression of NF-κB and ICAM-1 between SAP group and pioglitazone group （7.50 ±1.05 vs 11.33 ± 1.75, 0.80 ± 0.53 vs 1.36 ± 0.54, P 〈 0.01 or P 〈 0.05） at 12 h after the induction of pancreatitis. CONCLUSION： Pioglitazone attenuates the severity of SAP. The beneficial effect of pioglitazone is multifactorial due to its anti-inflammatory activities, most likely through the inhibition of ICAM-1 expression and NF-κB activation. Specific ligands of PPARy may represent the novel and effective means of clinical therapy for SAP.

Electrical Characteristics and Desorption Kinetics of Soil Boron

The status and activities of boron in soils were studied by the approach of electro-ultrafiltration (EUF). The samples of soils, including brown-red soil and calcareous alluvial soil, were collected from Hubei Province of China. The soil samples were incubated in saturated water and then their nutrients were ultrafiltrated with EUF equipment. Filtration and extraction were conducted in accordance with routine process, but fractions in anode and cathode were all collected. Analyses of B, K+, Mg2+, Ca2+, Cl- and pH in fractions supposed that boron existed not only in a simple form of borate but also in ion-pair with canons partly in acidic soil, and borate was the primary form existing in the calcareous soil. In studying desorption kinetics with EUF, the boron content of Fractions 2-6 was accumulated, and the accumulative quantities were fit to time factors in three kinetic equations: the zero-order, first-order, and parabolic diffusion equations. Fit degree of the parabolic diffusion equation was the best, followed by the zero-order equation, and the first-order equation was the worst.

Adsorption of Phosphate on Variable Charge Soils

The study about the adsorption of phosphate on four variable charge soils and some minerals revealed that two stage adsorption appeared in the adsorption isotherms of phosphate on 4 soils and there was a maximum adsorption on Al-oxide-typed surfaces between pH 3.5 to pH 5.5 as suspension pH changed from 2 to 9, but the adsorption amount of phosphate decreased continually as pH rose on Fe-oxide typed surfaces. The adsorption amount of phosphate and the maximum phosphate adsorption pH decreased in the order of yellow-red soil > lateritic red soil > red soil > paddy soil, which was coincided with the content order of amorphous Al oxide. The removement of organic matter and Fe oxide made the maximum phosphate adsorption pH rise from 4.0 to 5.0 and 4.5, respectively. The desorption curves with pH of four soils showed that phosphate desorbed least at pH 5. Generally the desorption was contrary to the adsorption with pH changing. There was a good accordance between adsorption or desorption and the concentration of Al in the suspension. The possible mechanisms of phosphate adsorption are discussed.

Novel Control Structure Design of Differential Pressure Thermally Coupled Reactive Distillation for Methyl Acetate Hydrolysis

In this paper, the novel control structures of differential pressure thermally coupled reactive distillation process for methyl acetate hydrolysis were proposed. The RadFrac module of Aspen Plus was adopted in the steady-state simulation. Sensitive analysis was applied to find the stable intial value and provide a basis for the improved control structure design. The Aspen Dynamics software was adopted to study the process dynamic behaviors, and two novel control structures provided with feed ratio controllers and sensitive tray temperature controllers were proposed. The reflux ratio controllers were applied in the improved novel control structures. Both control structures abandoned the composition controllers that were replaced by simpler controllers with which the product purity could meet the specification requiring under a ± 20% disturbance to the total feed flowrate / MeAc composition.

Variations of trace elements under hydrological conditions in the Min River, Eastern Tibetan Plateau

In order to better understand the relative importance of hydrologic variation and anthropogenic disturbance and their complex interactions within the trace elemental geochemical cycle, water samples were collected monthly over 1 year in the Min River, eastern Tibetan Plateau, and analyzed for trace element composition. The dissolved trace elements exhibited different relationships with increasing discharge compared with major elements.The elements analyzed can be divided into three groups according to their behavior in response to changing discharge:(1) elements that showed weak positive correlation with discharge, e.g. Cu, V, and Ba;(2) elements that exhibited weak negative correlation with discharge,including Rb, Sr, Pb, Sb, Zn, Cr, Cd, and U; and(3) elements that displayed no significant correlation with variation in discharge, e.g. Ti, Fe, Co, Ni, and As. Cu was strongly affected by anthropogenic activities and flushed into the river with increasing discharge. Ba has a strong solubility in the terrestrial environment, dissolved quickly,and was released into the river. The positive relationship between V concentration and discharge may be attributed to secondary reactions, such as precipitation and adsorption on oxides and aluminosilicate clays. Conservative behavior had an impact on the geochemical behavior of Sr and Rb across hydrologic variation. Pb, Zn, Sb, Cd, and Cr underwent a mild dilution effect connected with anthropogenic activities. The chemostatic behavior of U was regulated by carbonate dissolution and biological uptake.In addition, higher temperatures enhanced biotic activities,affecting the concentrations of Fe and Ni. The relationship between power law slopes and coefficient of variation for discharge and solute concentration suggests that concentrations of trace elements vary significantly with increasing discharge compared with major elements. Silicate mineral weathering had less effect on the fluvial solutes with increasing discharge. Mining activity may exert an additional control on concentration–discharge dynamics of anthropogenic trace elements.

The Structure of Ammonium D,L-Tartrate

The single crystals of the title compound NH4+C4H5O6- (C4H9NO6, Mr = 167.1) were obtained from a hot aqueous solution containing L-glutamine and D,L-tartaric acid in mole ratio1:1.5. The crystal belongs to monoclinic space group P21/c with a = 7.646(2), b = 7.804(2), c = 11.502(3)? ?= 102.26(2)o, V = 670.7(3)?, Z = 4, F(000) = 352, Dc = 1.655 g.cm-3, m(MoKa) = 0.16 mm-1, R = 0.035, wR = 0.094 for 1028 observed reflections (I>2s(I)). The enatiomeric anions of the tartrate with both (2S,3S)- and (2R,3R)-configuration co-exist in the unit cell. The carbon skeleton assumes a coplanar arrangement with a torsion angle of 181.5o. The three- dimensional H-bonding network exists in the crystal. While tartrate groups link each other by H-bonds between carboxyl and hydroxyl groups, the ammonium cations insert between the tartrate groups to form a sandwich-like crystal structure.

Volumetric and Viscometric Studies of 4-Aminobutyric Acid in Aqueous Solutions of Salbutamol Sulphate at 308.15, 313.15 and 318.15K

Density （ρ） and viscosity （η） measurements were carried out for 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·L-1 aqueous salbutamol sulphate at T=308.15,313.15 and 318.15K.The measured values of density and viscosity were used to estimate some important parameters such as apparent molar volume Vφ,limiting apparent molar volume Vφ0,transfer volume △Vφ0,hydration number Hn,second derivative of infinite dilution of partial molar volume with temperature 2Vφ0/T2,viscosity B-coefficients,variation of B with temperature dB/dT,free energy of activation per mole of solvent △μ10＊ and solute △μ20＊,activation entropy △S20＊ and activation enthalpy △H20＊ of the amino acids.These parameters have been interpreted in terms of solute-solute and solute-solvent interactions and structure making/breaking ability of solutes in the given solution.

Thermogravimetric Study and Modeling of Direct Sulfation of Limestone by Sulfur Dioxide

The direct sulfation of limestone from different sources in Iran was studiedin a thermogravimetric analyzer under atmospheric pressure. All limestone samples tested have higherthan 97% CaCO_3. Experimental conditions were as follows: particle size levels ranging from 1.6 μmto 7.8 μm, four level reaction temperatures (700℃, 750℃, 800℃ and 850℃), and two SO_2concentrations (2.4 x 10^(-3) and 3.2 x 10^(-3) mol · mol^(-1)). The particle size and temperatureshowed dominant influences on the rate and level of conversion while the effect of SO_2concentration was weak. The shrinking core model can be used to describe the behavior of thesulfation process. The reaction kinetics and diffusion mechanism are both important in controllingthe rate of the process. The two key parameters of the model, chemical rate constant K_s andeffective diffusion coefficient D_(eff) were obtained. Model predictions are in good agreement withthe experimental data.

Hydrolysate of corn starch saccharified with a dual-enzyme system and the effect on the crystallization of itaconic acid when used in fermentation

An improved process of hydrolysis of corn starch was adopted in the production of itaconic acid （IA）, the aim was to decrease the unfermentable reducing sugar （RS） in the medium from the beginning of the fermentation and to increase the crystallization efficiency of IA from the fermentation broth. The glucose （GS） syrups saccharified by several combinations of glucoamylase and pullulanase were investigated and used as the carbohydrate source of the fermentation medium for the spore-initiated submerged fermentations experiments. Compared with the conventional process （with pullulanase controlled）, the improved process decreased th.e RS residue in the fermentation broth from 3.01g/L to 1.35g/L and from 4.25g/L to 3.25g/L when the original RS of the medium were 100 and 120g/L, respectively. The crystallization efficiency of IA increased from 65% to 78.8% and from 69.58% to 82.81% with the original RS being 100 and 120g/L, respectively.

Denitrification of Coal Tar Diesel Fraction by Phosphate Imidazolium Based Polymeric Ionic Liquids

A series of highly cross-linked polymeric ionic liquids P[Ci(Vim)_2][Cl]_2(i = 2,3,4,5,6) were synthesized by quaternization reaction and polymerization,and used to remove nitrogen compounds from oils.The polymeric ionic liquids P[Ci(Vim)_2][H_2PO_4]_2(i = 2,3,4,5,6) were then obtained via ion exchange.The structures of P[C_4(Vim)_2][Cl]_2 and P[C_4(Vim)_2][H_2PO_4]_2 were characterized by Fourier transform infrared(FT-IR) spectroscopy,energy dispersive spectrometry(EDS),N2 adsorption-desorption isotherm measurements,scanning electron microscopy(SEM),thermogravimetric analysis and differential scanning calorimetry(TG/DSC).The removal of nitrogen compounds was characterized by pyridineFTIR spectrometry.The results indicated that P[C_4(Vim)_2][H_2PO_4]_2 with an average pore size of 19.23 nm and a specific surface area of 11.78 m^2/g was efficient for the removal of nitrogen compounds,and exhibited good thermal stability.The adsorption rate in the simulated oil reached 93.8% when using a polymeric ionic liquid P[C_4(Vim)_2][H_2PO_4]_2 to oil ratio of 0.04 and a temperature of 313 K.The nitrogen removal rate from the coal-tar diesel fraction achieved by P[C_4(Vim)_2][H_2PO_4]_2 was 90.3%.

Measurement of the Average Molecular Weight of Cotton Cellulose Crosslinked by a Polycarboxylic Acid at Different pH Using Multiple Angle Light Scattering Photometer in a DMAc/LiCl Solvent System

Durable press finishing of cotton fabrics with polycarboxylic acid increases fabric wrinkle-resistance at the expense of its mechanical strength. Severe tensile strength loss is the major disadvantage for wrinkle resistant cotton fabrics.Tensile strength loss of cotton fabric crosslinked by a polycarboxylic acid can be attributed to depolymerization and crosslink of cellulose molecules. Measurement of the molecular weight of cotton fabric before and after crosslinked by polycarboxylic acids can offer a possibility of direct understanding of the depolymerization. In this research, amultiple angle laser light scattering photometer was used todetermine the absolute molecular weight of cotton fabric treated with BTCA at different pH and then hydrolyzed with 0. 5 M NaOH solution at 50℃ for 144 h. The results indicate that average molecular weights of cotton fabric treated with polycarboxylic acids at different pH are almost the same.