Jing Dong

The Role of Copper in the Growth of Methylosinus trichosporium IMV 3011 and Poly-β-Hydroxybutyrate Biosynthesis

Methanotrophs are aerobic microorganisms that utilize methane as substrates for growth and PHB Biosynthesis. Copper plays an important role in cell growth and PHB biosynthesis. The effect of initial copper concentration on cultivation of M. trichosporium IMV 3011 on methane was investigated. With the addition of 30μmol/L CuSO4•5H2O, PMMO activity improved to 4 times of that without copper addition. The highest density of cultivated cells is 0.48g dry wtL-1, which is 2 times of that without copper addition. The lag time shortened to 15.87h, and the growth rate increased to 0.082h-1.The PHB content increased to 8.3%. It is found that certain initial copper concentration is beneficial to expression of high particulate methane monooxygenase activity, which may contribute to the synthesis of PHB in the cell.

Effect of Specific Ions in Preparing Water on Viscosity of Polyacrylamide Solution

Served as polymer flooding for the enhanced oil recovery, partially hydrolyzed polyacrylamide (PAM) has widely been employed for the oil production. The PAM solution prepared by the ground clean water was characterized with a higher viscosity in the early years while one, made by the oilfield produced water in the existence of complicated constituents, features a worse viscosity in the recent operation. In the practical opinion, the viscosity is an important indicator of the polymer flooding. The high viscosity of aqueous PAM solution has being pursued for a goal of the successful operation. For the reason, this research objective could be set toward seeking the causes of the viscosity degradation. In this paper, specific ions in the preparing water on effects of the PAM viscosity were identified and evaluated by the analysis of produced water quality used by the operation of preparation in Daqing oilfield. Effects of the specific ions on PAM viscosity were investigated in the lab test for understanding and controlling the viscosity. The results show that the dominant specific ions were found out to consist of the divalent cation (Ca2+ and Mg2+), trivalent cation (Al3+), divalent ferrous ion (Fe2+) and divalent sulfide ion (S2-) by means of the data and related chemical theory. Much notable viscosity degradation of PAM solutions was observed in the degree-viscosity curves as the role of most of the specific ion factors. Totally, the retention rate of the viscosity was obviously lowered with the extension of the specific ion by degrees. By the results, the mechanism of the viscosity degradation was briefly proposed and discussed. These data can be provided and suitably specified for the benefit of polymer flooding production.

Solar Thermo-coupled Electrochemical Oxidation of Aniline in Wastewater for the Complete Mineralization Beyond an Anodic Passivation Film

Herein, we report the solar thermal electrochemical process (STEP) aniline oxidation in wastewater for totally solving the two key obstacles of the huge energy consumption and passivation film in the electrochemical treatment. The process, fully driven by solar energy without input of any other energies, sustainably serves as an efficient thermoelectrochemical oxidation of aniline by the control of the thermochemical and electrochemical coordination. The thermocoupled electrochemical oxidation of aniline achieved a fast rate and high efficiency for the full minimization of aniline to CO2 with the stability of the electrode and without formation of polyaniline (PAN) passivation film. A clear mechanism of aniline oxidation indicated a switching of the reactive pathway by the STEP process. Due to the coupling of solar thermochemistry and electrochemistry, the electrochemical current remained stable, significantly improving the oxidation efficiency and mineralization rate by apparently decreasing the electrolytic potential when applied with high temperature. The oxidation rate of aniline and chemical oxygen demand (COD) removal rate could be lifted up to 2.03 and 2.47 times magnification compared to conventional electrolysis, respectively. We demonstrate that solar-driven STEP processes are capable of completely mineralizing aniline with high utilization of solar energy. STEP aniline oxidation can be utilized as a green, sustainable water treatment.

The adoption and mechanism of KIO4 for redox-equilibrated stabilization of FeO42− as an equalizer in water

The inherent thermodynamic instability of FeO42− in water restricts its applications in water treatment, battery, and organic synthesis. The objective of this paper was to research and develop an additive for stabilization and mechanism of aqueous FeO42− solution on the basis of a choice of the redox equilibration. In this study, it was found that FeO42− in water was stabilized by the right match and adoption of KIO4 called an equalizer. The redox thermodynamic analysis and dynamic experimental results show that the adoption of KIO4 equalizer greatly increased lifetime of FeO42− in water by orders of magnitude. The stabilization mechanism is attributed to occur via the effect of redox equilibrium of the FeO42− and the IO4− species, as well as the formation of an oxidizing chemical environment. This study opens up possibilities for stabilization of solid ferrate compounds, for example, for use in the water treatment and super-iron battery.

Effect of Physical Factors on Viscosity of Polyacrylamide Solution Prepared by Oilfield Produced Water

In the recent industrial practice, the produced water has been used for the preparation of polyacrylamide (PAM) for the enhancement of oil recovery in Chinese oilfields. With more affecting factors than the tap water, the produced water, originating from the existence of complicated constituents in the water, leads to the worth viscosity of the PAM solution. In this paper, the affecting factors were identified and evaluated by the analysis of the PAM operations of preparation, storage and production in Daqing oilfield. Effects of physical factors on PAM viscosity were studied in the lab test for understanding and controlling the viscosity. The results show that the dominant physical factors are composed of the heat, storage time, mechanical stress and photo/sonic radiation. Most notably viscosity degradation of PAM solution was exhibited by actions of most of the factors. By the results, the mechanism of the controlling viscosity was briefly proposed and discussed. These data can be provided and suitably specified for the benefit of polymer flooding production.

Effect of Reaction Conditions on ClO2-Oxidation Demulsification for Oil-Water Transition Layer in Settling Tank

In order to meet the need of separating oil from water in the settling tank of the oilfield, ClO2-oxidation demulsification for oil-water transition layer in settling tank is introduced. In this paper, effects of reaction conditions on ClO2-oxidation demulsification were studied. The results show that the reaction temperature, reaction time and PH value have a heavy effect on the dehydration rate of the oil-water transition layer. With the increasing of the reaction time, the dehydration rate largely rises, and it can reach 84.18% and keep steady when the reaction is in 4 hours. With going the temperature up, the dehydration rate increases in a nonlinear way, and it can reach 85.23% at the temperature of 55°C. By decreasing the PH value, the dehydration rate significantly rises, and the maximum dehydration rate of 84.18% was achieved when adding 0.5 vol. % of the acid. The chemistry was discussed based on the principles and experiments. By demonstrating the experimental data and discussion, we can effectively control the oxidation performance of chlorine dioxide, which is very meaningful for oilfield on the aspect of stable production of petroleum.

Oxidation Kinetics of Hazelnut Shelf-Life Prediction Model

The changing patterns of filbert peroxide value through the determination of different storage temperature conditions,research the dynamics characteristics of oxidative rancidity of filbert. By regression analysis base on the storage time and the logarithm of peroxide value,it concluded the grease oxidation reaction first-order kinetic equation of filbert.Using Arrhenius equation and Q10 model for 5 ~ 35 °C temperature within the shelf life of any temperature prediction model.