Abstract: This research introduced microwave synthesis process of HPAA (2-hydroxyphosphonoacetic acid) which was synthesized from glyoxylate and phosphorous acid. The optimized technological conditions was defined by orthogonal experiment. The mass proportion of phosphorous and glyoxylate was 1:1.2, catalyst mass was 1g, 95°C, 25min, and its yield rate was more than 90%. The molecular structure of product was characterized by IR spectrogram analysis. This method was simple、economical and practical.
Abstract: The modified polyacrylamide/organic montmorillonite (PAM/OMMT) flocculant was prepared by in-situ intercalation polymerization with acrylamide monomer and OMMT under CO2 inert atmosphere. The OMMT was synthesized with MMT and cetyl trimethyl ammonium bromide (CTAB) as intercalation agent by cationic exchange reaction. This flocculant was used to deal with coalmine wastewater. The effects of the flocculant dose on turbidity removal rate and settling time, the influent of pH value, temperature on turbidity removal rate and the comparison with PAM was studied. Experimental results show that PAM/OMMT is a kind of high efficient compound flocculating agent, the formation of hydrophobic micro in polymer surface area has strong adsorption ability and dispersing capability. Then MMT increased the quality of flocculant body so that flocculating settling time is shorter. Its turbidity removal rate can be as high as 95.5%. Compared with PAM, PAM/OMMT presents many advantages with higher turbidity removal rate, higher settling velocity, lower relatively sludge water content and lower sensitivity of temperature and pH in wastewater treatment process. Flocculant dosage in 10 to 20 mg/L is the optimal flocculation condition. Sludge water content treated by PAM/OMMT (63.4%) is relatively lower than PAM (80.2%).
Abstract: The esterification reaction kinetics of ethylene glycol (EG) with phenyl phosphonic acid (PPOA) and benzene phosphinic acid (BPA) were studied in this article. Reactions were all carried out using benzene as a water carrying agent, and the reactant concentrations were determined by titration with NaOH. The reaction mechanisms were explained respectively. Various factors that may affect the extent of reaction were investigated such as reaction time and reaction temperature. The kinetic model of the apparent reaction was built. It was found that the apparent reactions both followed the pseudo-second order mode and the activation energy wre EPPOA 62.631 kJ/mol, EBPA 32.673 kJ/mol, respectively.
Abstract: Activated carbon made by clean coal and 25% coconut shell was selected to be modified with different concentrations’ HNO3. The productions were characterized by BET, XPS, FTIR and the moisture adsorption of performance is investigated by the DVSA-STD dynamic vapor analyzer. The results show that specific surface area of the activated carbon modified by the 10% concentration of HNO3 is improved 1.3 times than the unmodified one. By comparison the higher concentrations of HNO3 have weaker effects on the specific area of activated carbon. The water vapor adsorption capacity of activated carbon modified by HNO3 at 10% concentration is 1.5 times higher than the unmodified at room temperature at30% RH.
Abstract: High molecular weight lignosulfonate was oxidatively degrdadated into lower molecular weight fractions, the resulting components were conducted to formulate resol resin with phenol and formaldehyde in an alkaline condition, in which 50% phenol was substituted. The modified resol resin was successfully applied to prepare phenolic foam using appropriate combinations of flowing agents. N-pentane was found to be suitable as the foaming agent. Sulphuric acid (50% aqueous solution, w/w) and Tween-80 were used as catalyst and surfactant, respectively. The obtained foams showed satisfactory mechanical properties and excellent uniform cells, which can comply with the required specifications for its practical utilization.
Abstract: 0.5g/L of kaolin suspension was took as the sample for coagulation. The jar test was adopted to examine the effects of the Compound Bioflocculant (CBF) dosage, hydrogen ion concentration (pH) and the CaCl2 dosage as coagulation aid on the removal efficiency of turbidity. The experimental results showed that CBF had an effective performance with dosage of 4-5mg/L in the alkalescence environment. The optimal conditions for the removal efficiency of turbidity by CBF were the dosage of 4ml/L and pH of 7.5. CBF added coagulation aid(CaCl2) could play effect of flocculation. Adding 1.0ml / L of 10% concentration solution of CaCl2 could achieve the best flocculation effect. Temperature had minimal impact on the removal efficiency of turbidity , it indicated that the removal rate of turbidity at low temperatures was not obviously influenced.
Abstract: In aqueous solution, the modified polyether (F108), maleic anhydride (MA), acrylic acid (AA) as raw materials, a novel polycarboxylate high performance water reducer of MA-AA-F108 was synthesised from free radical copolymerized through oxidation-reduction initiator system. Additionally, the polymerization conditions were optimized. The results indicate that the copolymer can be prepared under such optimum conditions, i.e., 3:3:2 molar ratio of MA, AA and F108, 0.5% of the mass fraction of oxidation initiator, 0.6% of the mass fraction of reduced initiator and 0.3% of the mass fraction of regulator, the results showed that the polyether-type polycarboxylic water reducer has excellent dispersing ability.
Abstract: A polystyrene-supported 1-(propyl-3-sulfonate)-3-methy-imidazolium hydrosulfate acidic ionic liquid (PS-[SO3H-PMIM][HSO4]) catalyst was prepared by grafting and characterized by FT-IR, SEM/TEM, elements analysis, TG/DSC and acid base titration. It exhibited higher catalytic activity and improved para-selectivity than its homogenous counterpart for the nitration of toluene with 68% nitric acid. The catalytic activity of this catalyst decreased slightly after fifth runs in the synthesis of nitrotoluene.
Abstract: A new carrier-free cross-linked aggregates of cellulase (CLEAs-C) via precipitation with ammonia sulfate and cross-linking with glutaraldehyde was prepared. Efficient enzyme activity was obtained when cellulase and glutaraldehyde concentration was 50mg/mL and 3% (v/v) respectively. The cross-linking time and temperature were also important parameters for immobilization. Optimal temperature and pH of the CLEA–C were evaluated. The CLEAs-C displayed good stabilities, after stored at 4○C for 28 days storage, the CLEAs retained more than 80% initial activities.
Abstract: According to the techniques of the mashing and the Gaussian plume modeling, combining all kinds of the factors variation, such as the tanks leak velocity, the leak height, the wind direction and speed, and the environmental stabilization grade, the concentration distributing rules of the toxic gas continuous diffusion in the tank farm are simulated. Firstly, focusing on the central of the tank farm in chemical industrial park, mashes the tank farm as the research units for quantitative analysis and superposition calculation. Secondly, constructs the diffusion concentration distributing model of the toxic gas leak based on the Gaussian plume theory. Finally, by the condition of the single-leak hazard installation and the multiple-leak major hazard installations, the toxic gas continuous diffusion algorithms are studied, viz. in accordance with any of the influence factors variation, carve up the time sections, and then basing on Matlab technique, integrating the concentration superposition effects, simulate the concentrated distribution process of the noxious substance during the influence fields. Taking ammonia gas tank farm leakage as example, the simulation results show that the method may provide technological support for major hazard prevention and control in chemical industry park.