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Oil soluble viscosity reducers have gradually attracted the attention of petrochemical research due to their cleanliness and high efficiency. Considering the high viscosity and non-Newtonian fluid properties of Chenping heavy oil found in China, a series of new oil soluble viscosity reducers with different proportions and molecular weights were prepared by free radical polymerization using octadecyl acrylate, 2-Allylphenol and N-Methylolacrylamide as monomers. The viscosity reducer was applied to different types of heavy oil and found that it exhibited a better effect on heavy oils with high asphaltene content. The test of rheological behavior of heavy oil with additive was performed at wide range of shear rate (3-90 s-1) and temperature range (30-100 ℃). The apparent viscosity reduction rate was up to 70.09 %, which was better than the industrially relevant ethylene-vinyl acetate copolymer under the same test condition. In addition, the effect of viscosity reducers on the components of heavy oil and the energy change of the system simulated by molecular dynamics simultaneously was investigated. The consistency of the simulated and experimental results show that the effect of viscosity reduction closely related to the crystallization process of wax and the viscosity reducer can reconstruct the surface structure of asphaltene and diminish the connection of benzene ring.

The presence of water in organic systems usually inhibits the activity of the reaction. In the biphasic system composed of water-decane, the distribution of lignin-derived m-cresol hydrodeoxygenation (HDO) products catalyzed by Ni-Sn was affected with the presence of water. Water can facilitate the hydrogenation process by the dissociating water to produce H protons. However, the formation of complete deoxidation products may be inhibited because of the catalyst surface reconstruction and the low solubility in aqueous system. The DFT calculation theoretically revealed that the existence of water can lower the barrier and stabilize the transition state, but also affect the rupture of the CAr-O bond. Also, the significant characteristics of solvent action were explained by the hydrogenation and the solvatochromic parameters. Among them, m-cresol has a good performance in hydrocarbon solvents (CnH2n) and hydrogen bond donor (HBD) solvents. However, the catalytic activity decreases in alcohols due to the synergistic effects like H-bond and competitive adsorption between solvent and the substrate. The mechanism of the solvent effects with different properties can provide reference for the subsequent expansion of the system in a wide range. Therefore, the synergy between solvent and the catalyst provides a promising method for upgrading reclaimed chemicals from lignin.

Traditional NiFe alloy catalyst (NiFe AC) possesses low alcohol selectivity for the hydrodeoxygenation (HDO) of fatty acid due to its excessive deoxygenation into alkane. Herein, we innovatively provide the NiFe alloy oxide catalyst (NiFe AOC) to suppress the adsorption of aldehyde, which is the crucial intermediate of objective product alcohol converting into a side product, via the steric hindrance of lattice oxygen to inhibit the further conversion of alcohol. NiFe AOC reaches 100% conversion of lauric acid with 90% selectivity to lauryl alcohol. Kinetic analysis indicated that the apparent activation energy of side reaction increases by 71.1 kJ/mol for NiFe AOC relative to NiFe AC, evidencing the inhibition for the conversion of objective product alcohol into alkane for NiFe AOC. Furthermore, DFT calculation also suggests that the activation energy of the side reaction increases by 0.33 eV on NiFe AOC compared to NiFe AC. In addition, used NiFe AOC can be totally regenerated via surface reconstruction during the reduction-reoxidation treatment. However, overoxidation inducing NiFe surface phase separation weakened the synergistic interaction of Ni-Fe bimetallic sites and further decreased the catalytic activity.

Hybrid smart emulsification systems are highly applicable in manipulating oil-in-water (O/W) droplets. Herein, novel switchable block polymers containing both zwitterionic and tertiary amine pendent groups were designed and synthesized to combine with charged silica particles to stabilize the O/W emulsion responsive to pH. This study was carried out in O/W emulsions stabilized with the polymer and silica particles under different pH conditions. The emulsion system was also simulated using molecular dynamics simulation to reveal the mechanism at molecular levels, thus gaining insight into the relationships between the emulsifying properties and the molecular interaction of the mixed system. Upon acidification of the continuous aqueous phase, protonated polymers with excellent hydrophilicity were induced by charged silica particles to cause rapid emulsion coalescence. In alkaline media, the mixed system conversely stabilized the O/W emulsions, cutting polymer consumption by over three-quarters. The emulsification and demulsification can be switched alternately by tuning the pH conditions. The applications exhibited excellent efficiency in separating heavy oil/water emulsions and proved the high conversion rate in emulsion polymerization. Overall, with this novel strategy to relieve tedious modifications on particle surfaces and massive consumption of polymers, the designed responsive emulsification systems can impart intelligent and controllable chemical reactivity to emulsions on demand in a more affordable and sustainable way.

Faced with the increasing shortage of conventional oil, heavy oil has shown great potential. However, high viscosity of heavy oil hinder the use of traditional exploitation and transportation metho...

The use of an appropriate viscosity reducer is the key during the process of heavy crude oil exploitation. To design a new amphiphilic polymer as an efficient viscosity reducer, we combined the dissipative particle dynamics (DPD) simulation and all-atom simulation in this work to reveal the viscosity reduction mechanism. Nine primary polymers were added into the oil–water system, in which the oil–water volume ratio was 4:1, by comparing the mean-square displacement (MSD) of asphaltene, aggregation ratio, the oil–water interfacial tension value, and the effects of nitrogen type, benzene ring morphology, and the alkyl side-chain length of the polymers on the properties of the system. The interaction mechanism was further revealed by analyzing the interaction energy between the asphaltene and the polymer molecules at the atomic scale. Finally, three kinds of polymers, P12, P22, and P31, which used polyacrylamide as a skeleton and were modified by pyrrolidone, a naphthalene ring, and the alkyl side chain without a −CH₂ group, respectively, were selected to design a new amphiphilic polymer as a viscosity reducer. This work combined the advantages of the mesoscopic and atomic simulation methods to design the amphiphilic polymer, shedding light on the development of the novel heavy-oil viscosity reducer.

Heavy crude oil is one of the most potential fossil fuels at present and in the future. However, its high viscosity severely hinders its recovery from reservoir conditions. Heavy oil viscosity redu...

Hydrodeoxygenation (HDO) is a promising way to produce the second generation bio-diesel from aliphatic acid based biomass. Compared with the monometallic Ni/SiO2, appropriate introduction of Fe results in the complete conversion of lauric acid and nearly 100% yield of alkane as well as satisfactory stability on conversion. Further study on mechanism shows that the NiFe intermetallic compounds (IMC) catalyst promotes the ratedetermining step, i.e., C11H23COOH → C11H23CHO, which is attributed to the synergistic effect of Ni-Fe bimetallic sites according to the characterization and calculation. For one thing, strong spin polarization enhances the interaction between Fe sites and aliphatic acid, and the subsequent dissociation of C-OH bond indicated by the DOS and transition state analysis. For another, dissociation of H2 on Ni site is promoted because of the higher charge density around Ni in the IMC according to the in-suit FTIR and Bader analysis. However, with the repeated use of the catalyst, the selectivity to alkane decreased gradually, which is ascribed to the oxidation of metal Ni-Fe bimetallic sites. This demonstrates that the reduced Ni-Fe bimetallic sites rather than the oxidized ones are the active phases in the HDO of aliphatic acid to produce alkanes with the NiFe IMC.

In this work, the Peng–Robinson (PR) equation of state (EoS) and MHV2 mixing rule that were combined with UNIFAC and NRTL GE models were used to predict vapor–liquid phase equilibrium (VLE) data for CO2–hydrocarbon systems. These systems included 12 binary systems and three ternary systems. The PRMHV2-UNIFAC model was used to calculate the bubble pressure, and the average absolute relative deviations (AARD %) were 17.49–32.20% for 12 binary systems. For the PRMHV2-NRTL model, the binary interaction parameters of the NRTL model dependent on temperature were regressed based on the binary VLE data. These new interaction parameters were used to estimate CO2–hydrocarbon VLE data for binary and ternary systems. The bubble pressure was predicted by the PRMHV2-NRTL model, and the AARD % values were 1.52–9.44% for binary systems, which were lower than the value of the PRMHV2-UNIFAC model. The PRMHV2-UNIFAC and PRMHV2-NRTL models were also used to calculate the liquid phase mole fraction of CO2–hydrocarbon ternary ...

The phase equilibrium data of CO2–hydrocarbon binary mixtures are important for the design and operation of CO2 flooding, coal liquefaction, and supercritical extraction processes. Numerous pieces of binary phase equilibrium data have been obtained. Thus, models for the accurate calculation of binary and multicomponent mixtures must be developed on the basis of existing data. In this work, 3578 vapor–liquid phase equilibrium data points for 10 CO2–hydrocarbon binary mixtures, including CO2–butane, CO2–pentane, CO2–isopentane, CO2–hexane, CO2–benzene, CO2–heptane, CO2–octane, CO2–nonane, CO2–decane, and CO2–undecane, were collected. The PR and PR-BM equations of state (EOS) in combination with relevant mixing rules were used to calculate the phase equilibrium data of the CO2–hydrocarbon binary mixtures. The binary interaction parameter kij in the PR EOS was temperature independent, whereas parameters in the PR-BM EOS were functions of temperature. Thus, the phase equilibrium data and other thermodynamic properties of the binary and multicomponent mixtures at different temperatures and pressures can be calculated by using the parameters obtained in this work. The PR-BM EOS performed better than the PR EOS, and the average absolute deviations over the temperature range of 255.98–408.15 K calculated by the PR EOS and PR-BM EOS were less than 5.74% and 3.36%, respectively. The results calculated by the two EOS were compared with those calculated by other models, such as PPR78, PR + LCVM + UNIFAC, KIE + PR EOS + HV, and PSRK. The phase equilibrium data of CO2–butane–decane, CO2–hexane–decane, and CO2–octane–decane ternary mixtures were calculated by the two EOS. The average overall deviations for the CO2 mole fractions calculated by the two EOS were less than 7.66%.

The catalytic hydrotreatment of fast pyrolysis liquids (PL) from lignocellulosic biomass is a promising technology to improve the properties of PL. Mild hydrotreatment (< 250 °C) using a suitable catalyst allows the production of stabilized oils that have for instance potential for co-processing in existing oil refinery units. Here, we report a catalyst screening study to stabilize PL by a mild hydrotreatment using five Raney nickel “type” catalysts (Ra-Ni), more specifically a benchmark Ra-Ni, two types of Fe/Cr promoted, and two Mo-promoted ones. Experiments were performed at relatively mild hydrotreatment conditions (200 °C, initial 140 bar H2 pressure, 4 h) in a batch autoclave. Among all the Ra-Ni catalysts, the Mo promoted (A-7063) showed the highest hydro-(deoxy)genation activity, a lower extent of repolymerization (GPC), and lower charring tendency of the product oil (TGA) compared to the promoter-free and Fe/Cr promoted Ra-Ni catalysts. Analyses of the product oils showed that the oils contain a significant amount of phenolics (7.4–15.4 wt% on oil, GC x GC-FID). These findings indicate that commercially available Raney nickel “type” catalysts, and particularly the Mo promoted ones, are attractive to be used for the mild hydrotreatment of pyrolysis liquids.

For the high-value utilization of tuna liver, the effects of acid-aided (Acid-pH) and alkali-aided pH-shifting (Alkali-pH) on the physicochemical and functional properties of the protein powder prepared by pH-shifting and freeze-drying were studied. As expected, the protein powder with high purity could be obtained through Acid-pH or Alkali-pH followed by freeze drying, while the Alkali-pH led to a higher protein yield, higher protein ratio, lower lipid ratio and lower heavy metal content than Acid-pH. The amino acid profile of the protein powder prepared by Alkali-pH (Alkali-PP) was similar with that prepared by Acid-pH (Acid-PP). In addition, compared with Acid-PP, the Alkali-PP possessed the greater capacities in emulsion activity, foaming capacity and fat absorption capacity. Furthermore, the foaming capacity, foam stability and fat absorption capacity of Alkali-PP was better than soy protein powder. Therefore, Alkali-pH followed by freeze-drying would be a better alternative to prepare high-quality protein powder from tuna liver in the food industry.

Repolymerization is a huge problem in the storage and processing of biomass pyrolysis liquid (PL). Herein, to solve the problem of repolymerization, mild catalytic hydrotreatment of PL was conducted to convert unstable PL model compounds (hydroxyacetone, furfural, and phenol) into stable alcohols. An Ni/SiO2 catalyst was synthesized by the deposition-precipitation method and used in a mild hydrotreatment process. The mild hydrotreatment of the single model compound was studied to determine the reaction pathways, which provided guidance for improving the selectivity of stable intermediate alcohols through the control of reaction conditions. More importantly, the mild hydrotreatment of mixed model compounds was evaluated to simulate the PL more factually. In addition, the effect of the interaction between hydroxyacetone, furfural, and phenol during the catalytic hydrotreatment was also explored. There was a strange phenomenon observed in that phenol was not converted in the initial stage of the hydrotreatment of mixed model compounds. Thermogravimetric analysis (TGA), Ultraviolet-Raman (UV-Raman), and Brunauer−Emmett−Teller (BET) characterization of catalysts used in the hydrotreatment of single and mixed model compounds demonstrated that this phenomenon did not mainly arise from the irreversible deactivation of catalysts caused by carbon deposition, but the competitive adsorption among hydroxyacetone, furfural, and phenol during the mild hydrotreatment of mixed model compounds.

Pyrolysis oil is a promising material for renewable energy through a hydrogenation process. However, the polymerization, initiated especially by pyrolysis oil water-soluble fraction (PS), is a big hurdle to hydrogenation. The types and structures of the polymerization chemicals, their polymerization mechanisms are very important for upgrading pyrolysis oil. This study firstly compared the polymerization rates of water-soluble fraction (PS) and water-insoluble fraction (PL) by accelerating aging fresh PS and PL at different temperatures (80 °C, 90 °C, 100 °C and 110 °C) for 24 h and at 110 °C for different durations (12 h, 24 h, 36 h, 48 h and 60 h), respectively. The thermogravimetric and differential thermogravimetry analysis results showed that PS polymerized much more rapidly than PL. Then, PS polymerization was further investigated by evaluating the changes in its physical properties (water content, viscosity and element content) and chemical compositions (gas chromatography and liquid chromatogram) before and after aging. The results showed that hydroxy aldehydes and ketones (especially glycoaldehyde, hydroxyacetone and levoglucosan), dicarbonyl compounds (especially succindialdehyde) and α, β-unsaturated carbonyl compounds (especially 3-methyl-2-cyclopenten-1-one and dehydrate resultants of some aldol condensation products) were mainly responsible for PS polymerization.

The viscosity of ionic liquids (ILs) plays an important role in the chemical industry, material science and environmental science. This work presents a temperature- and pressure-dependent (η-T-P) model based on the norm indices for describing the viscosity of ILs. While the parameters for the temperature and pressure dependence of the viscosity have been generally set as constants in previous work, they are adjusted based on the molecular structures in the η-T-P model. Because ILs consist of only cations and anions, the norm indices are derived from cations and anions, respectively. However, the close connection between the interaction of the cations and anions and IL viscosity cannot be neglected; therefore, another set of norms is further deduced to represent the cation–anion interaction. The η-T-P model is developed using 349 ILs (3228 data points) in the temperature range of 253.15–573.00 K and the pressure range of 0.06–300.00 MPa. Consequently, a η-T-P model is derived with convincing results, as evaluated by the following statistical parameters: the squared correlation coefficient (R2), Fisher significance (F) and the overall average absolute relative deviation (AARD), which are 0.964, 1809 and 4.62%, respectively.

The quantitative structure–activity relationship (QSAR) model is an effective alternative to traditional experimental toxicity testing, which is undoubtedly important for modern environmental risk assessment and property prediction. Based on this background, the toxicological effects of ionic liquids (ILs) against Candida albicans (C. albicans) were studied via the QSAR method. A large diverse group of 141 and 85 ILs that have a minimal inhibitory concentration (MIC) and a minimum fungicidal concentration (MBC) against C. albicans were used to obtain multiple linear regression models. These two models were developed based on matrix norm indexes and proposed based on the atomic character and position. Matrix norm indexes proposed in our research group were used to calculate the toxicity of these ILs towards C. albicans for the first time. These two models precisely estimated the toxicity of these ILs towards C. albicans with a square of correlation coefficient (R2) of = 0.930 and a standard error of estimate (SE) of = 0.254 for pMIC, and for pMBC, R2 = 0.873 and SE = 0.243.

Faced with the problem of high viscosity of heavy oil, revealing interaction mechanism of viscosity reduction from molecular level is of significance for scientifically designing viscosity reducers. Therefore, molecular dynamics (MD) and quantum mechanics (QM) simulations were combined to conduct a profound research on viscosity reduction mechanism of heavy oil. Three kinds of viscosity reducers (VRs) used in experiment were modeled and inserted into the heavy oil box systems constructed for simulation. By comparing average cluster sizes of asphaltenes in each system, and interactions between the characteristic atoms in the VRs’ branches and asphaltenes, the difference in the effects of different viscosity reducers were fully understood. After analyzing the π-π stacking forms among asphaltenes-asphaltenes, asphaltenes-resins, and resins-resins in different simulation systems, a potential viscosity reduction mechanism was proposed. The strong face-face stacking between asphaltenes and asphaltenes in heavy oil is converted into a relatively weaker face-face stacking of asphaltene-resin, with weak interaction type and strength among heavy oil molecules further explored. Finally, a criterion for screening solvents was put forward after investigating the property of different solvents, toluene and kerosene. Molecule simulation was carried out to reveal the mechanism for viscosity reduction of heavy oil under molecular level, which made a contribution to the exploration of heavy oil.

Biomass pyrolysis oil is a renewable resource and some of compounds (such as ketones, phenols and furans) in biomass pyrolysis oil are very useful compounds that can be used as raw materials for production of fine chemicals. Vapor-liquid equilibrium (VLE) data are critical and fundamental for designing distillation separation process. The VLE experiment and calculation of ketone-related binary systems (2-butanone + cyclopentanone, 2,3-butanedione + cyclopentanone) at atmospheric pressure are studied in this work. Binary interaction parameters of activity coefficient models (NRTL, Wilson and UNIQUAC) are obtained by correlating VLE experimental data. The new group CH2COCH2 is defined and the new group interaction parameters are presented and used to predict VLE data by UNIFAC-DMD model. The distillation separation process of ketones is designed and simulated based on VLE results. This work will provide theoretical basis and technical guidance for industrial separation process of biomass pyrolysis oil.

Carbon dioxide enhanced oil recovery (CO 2 EOR) process is widely used in petroleum industry in recent years. But it has some shortcomings, such as early gas breakthrough, fingering, asphaltene precipitations, because of the low viscosity and density of CO 2 . These problems can be resolved by adding some common solvents as chemical modifiers in CO 2 flooding. In this work, ethanol was chosen as the chemical modifier. The effects of ethanol on the equilibrium interfacial tension (IFT) of paraffin + CO 2 systems were investigated with different ethanol contents, temperature range 60–100 °C and pressure range 5.06–14.60 MPa, respectively. New correlation for predicting the IFTs of paraffin + modified CO 2 systems were proposed based on 150 experimental IFT values. The square of correlation coefficient ( R 2 ), root mean square error ( RMSE ) and average absolute relative deviations ( AARD ) were 0.9948, 0.15 and 2.49%, respectively. The paraffin IFTs for modified CO 2 and pure CO 2 flooding were compared by the IFT average absolute decrease ratio ( AADR ).

Ionic liquids (ILs) have attracted much attention in the past few years for their distinctive properties. Thermal conductivity plays an important role in industrial applications. This work presents a linear model based on the norm-indexes to describe the relationship between ILs thermal conductivity and their structure as well as temperature and pressure. A total data set of 475 experimental thermal conductivity data points under a wide range of temperatures (273.15–355.07K) and pressures (0.1–20.0 MPa) for five types of ionic liquids containing ammonium, phosphonium, imidazolium, pyridinium, and pyrrolidinium were employed to train and test the model. The results revealed that this proposed method presented a good accuracy with high F of 1540, high R2 of 0.984, and low AARD of 1.45%. In addition, the good results of 5-fold cross-validation, external validation, Y-randomization test, as well as applicability domain further illustrate the stability and reliability of this work. Accordingly, this norm-index...

Interfacial tension (IFT) is crucial for characterizing the phase and interphase behavior in the enhanced oil recovery (EOR) process. CO2 and N2 are commonly used as injection gases in the EOR process. In this work, an experimental apparatus using the pendent drop method was adopted to measure IFTs for the EOR process with different injection gases, temperatures (40.0–120.0 °C) and pressures (0.22–17.32 MPa). The relative Gibbs adsorption isotherm (Γij) of a species i on species j were calculated by the experimental IFTs. Theoretically, new correlations were proposed to predict paraffin IFTs for pure CO2 and mixture gas (CO2 + N2) injection. A total of 561 and 268 experimental IFTs were used to derive the correlations for pure CO2 and mixture gas injection, respectively. The square of correlation coefficient (R2), root mean square error (RMSE) and average absolute relative deviations (AARD) for pure CO2 were 0.9884, 0.58 and 5.45%, respectively. For the mixture gas injection, the R2, RMSE and AARD of the correlation were 0.9851, 0.57 and 4.47%, respectively.

BACKGROUND: Fast pyrolysis of lignocellulosics has provided an abundant sugar source for production of value-added chemicals, and levoglucosan is the most representative sugar in pyrolysis liquid (bio oil). This paper explored the potential for producing methyl lactate from levoglucosan by employing the mixed catalysts of zeolite tin beta (Sn-Beta) and zeolite hydrogen beta (H-Beta). RESULTS: Under the optimal conditions (at 200 °C and mixed catalysts with H-Beta:Sn-Beta ratio of 1:5), the yield of methyl lactate obtained from levoglucosan conversion was as high as 35%. And the yield was comparable to that of methyl lactate obtained from glucose conversion under the similar conditions (at 200 °C and pure Sn-Beta). In order to investigate the reason, a contrasting experiment with glucose as substrate also was carried out with the mixed catalysts. The results indicated that during the levoglucosan conversion process, ‘the methanolysis of levoglucosan’ was likely to compete with ‘the dehydration of glucose’ for the Brønsted acid sites of H-Beta. In addition, the catalytic functions of H-Beta and Sn-Beta, and the reaction pathway were deeply investigated through tracking and comparing the conversion of levoglucosan over mixed H-Beta/Sn-Beta and over pure Sn-Beta catalysts, respectively. CONCLUSION: The appropriately lower ratio of H-Beta:Sn-Beta and relatively higher temperature were favorable for the reaction. H-Beta containing Brønsted acid could remarkably accelerate the conversion of levoglucosan and methyl-glucosides to glucose. Sn-Beta containing Lewis acid mainly promoted the retro-aldol condensation of glucose and formation of methyl lactate.

The production of valuable chemicals and fuels from pyrolysis oil or its fractions is an appealing strategy. Glycolic acid and formic acid have widespread applications in the food processing and chemical industries. Here we investigated the feasibility of generating glycolic acid and formic acid from pyrolysis oil water-soluble fraction (WS) using H3PMo12O40·nH2O catalyst. Firstly, in order to clarify the possible reaction pathways in WS oxidation process, levoglucosan and glycolaldehyde, two principal substances present in WS, were respectively used as the substrate for oxidation to the two acids. Secondly, in order to find the optimum reaction conditions, the conversion of a mixture of levoglucosan and glycolaldehyde, as a surrogate of WS, was investigated under various process conditions. Thirdly, the actual WS was tested under the optimum reaction conditions, and the result gave a glycolic acid yield of 15.7% and a formic acid yield of 27.4%. Owing to the negative effects of phenols, cyclopentanones and furans in it, the result was different from that obtained with model mixture as substrate, in terms of the total yield of the two acids and the selectivity of glycolic acid over formic acid. Among various purifying methods of WS, activated carbon adsorption was effective, which resulted in a glycolic acid yield of 31.7% and a formic acid yield of 23.6%, making the conversion result of processed WS close to the conversion result of model mixture.

The effect of zeolite solid acids on the in situ hydrogenation of bio-derived phenol over Raney Ni was investigated, which indicated that the conversion of phenol increased with the addition of zeolite solid acids and Hbeta (Si/Al = 60) showed the best performance of high phenol conversion and selectivity towards the desired products and low carbon loss. In addition, the quantity of Hbeta (Si/Al = 60) and Raney Ni had marked impact on the carbon loss, but little effect on both the conversion and the products distribution. And the mixed catalysts of Raney Ni and Hbeta (Si/Al = 60) exhibited excellent stability.

The magnetic biochars were easily fabricated by thermal pyrolysis of Fe(NO3)3 and distillation residue derived from rice straw pyrolysis oil at 400, 600 and 800°C. The effects of pyrolysis temperature on characteristics of magnetic biochars as well as adsorption capacity for aromatic contaminants (i.e., anisole, phenol and guaiacol) were investigated carefully. The degree of carbonization of magnetic biochars become higher as pyrolysis temperature increasing. The magnetic biochar reached the largest surface area and pore volume at the pyrolysis temperature of 600°C due to pores blocking in biochar during pyrolysis at 800°C. Based on batch adsorption experiments, the used adsorbent could be magnetically separated and the adsorption capacity of anisole on magnetic biochars was stronger than that of phenol and guaiacol. The properties of magnetic biochar, including surface area, pore volume, aromaticity, grapheme-like-structure and iron oxide (γ-Fe2O3) particles, showed pronounced effects on the adsorption performance of aromatic contaminants.

Co-combustion of lignite with distillation residue derived from rice straw pyrolysis oil was investigated by non-isothermal thermogravimetric analysis (TGA). The addition of distillation residue improved the reactivity and combustion efficiency of lignite, such as increasing the weight loss rate at peak temperature and decreasing the burnout temperature and the total burnout. With increasing distillation residue content in the blended fuels, the synergistic interactions between distillation residue and lignite firstly increased and then decreased during co-combustion stage. Results of XRF, FTIR, (13)C NMR and SEM analysis indicated that chemical structure, mineral components and morphology of samples have great influence on the synergistic interactions. The combustion mechanisms and kinetic parameters were calculated by the Coats Redfern model, suggesting that the lowest apparent activation energy (120.19kJ/mol) for the blended fuels was obtained by blending 60wt.% distillation residue during main co-combustion stage.

The search and development of anti-HIV drugs is currently one of the most urgent tasks of pharmacological studies. In this work, a quantitative structure–activity relationship (QSAR) model based on some new norm indexes, was obtained to a series of more than 150 HEPT derivatives (1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine) to find their pEC 50 (the required effective concentration to achieve 50% protection of MT-4 cells against the cytopathic effect of virus) and pCC 50 (the required cytotoxic concentration to reduce visibility of 50% mock infected cell) activities. The model efficiencies were then validated using the leave-one-out cross validation (LOO-CV) and y-randomization test. Results indicated that this new model was efficient and could provide satisfactory results for prediction of pEC 50 and pCC 50 with the higher R train 2 and the higher R test 2 . By using the leverage approach, the applicability domain of this model was further investigated and no response outlier was detected for HEPT derivatives involved in this work. Comparison results with reference methods demonstrated that this new method could result in significant improvements for predicting pEC 50 and pCC 50 of anti-HIV HEPT derivatives. Moreover, results shown in this present study suggested that these two absolutely different activities pEC 50 and pCC 50 of anti-HIV HEPT derivatives could be predicted well with a totally similar QSAR model, which indicated that this model might have the potential to be further utilized for other biological activities of HEPT derivatives.

In order to obtain the solubility values for the diesel/biodiesel/methanol blends and prepare the homogeneous single blended fuels, biodiesel or diesel was composed approximately of a series of model compounds and the liquid–liquid equilibrium (LLE) data for the seven ternary and one quaternary systems involving in n-alkane, fatty acid methyl ester and methanol have been measured and performed thermodynamic modeling. The experimental data were correlated by NRTL model and UNIFAC-Dortmund model with a good accuracy. The new parameters of NRTL and UNIFAC-Dortmund models were obtained systematically and they were tested to be reliable for the (diesel + biodiesel + methanol) system through the prediction of some experimental and literature data. Meanwhile, the phase chart for the (diesel + biodiesel + methanol) mixture was successfully simulated using Aspen Plus software based on the obtained NRTL and UNIFAC-Dortmund models parameters, which was applied to investigate the compatibility of biodiesel/diesel/methanol blended fuel. In this work, the diesel/biodiesel/methanol blended fuel containing 30% biodiesel is likely to be border-line in terms of homogeneous system.

In this work, liquid–liquid equilibrium (LLE) data for the two ternary systems methyl laurate + ethanol + glycerol and methyl myristate + ethanol + glycerol were measured at 318.15 K and 333.15 K under atmospheric pressure. The reliability of the experimental tie-line data was checked by the Othmer–Tobias correlation. The LLE experimental data were correlated with the nonrandom two-liquid (NRTL) model, and the binary interaction parameters were regressed by the data fitting. The correlated results agreed satisfactorily with the experimental results.

In this work, the solubility of CO2 in three binary hydrocarbon mixtures of different molecular structures, hexane + cyclohexane, cyclopentane + ethylbenzene and toluene + undecane at 313.15 K, 343.15 K, 373.15 K and pressures up to 13.83 MPa were measured. The solubility measurements were undertaken in the designed apparatus. The experimental results show that the solubilities of CO2 in the binary hydrocarbon mixtures are mainly affected by the molecular structure and carbon numbers of hydrocarbon. The more ratios of high-carbon hydrocarbon in the mixtures, the lower solubility of CO2 is. The experimental data were compared with the calculated results of PR and PSRK models. The average absolute relative deviations of bubble pressure were 2.54%–5.66% and 1.45%–7.66%, respectively. Both models gave satisfied results, while the PR was superior to PSRK when the interaction parameters of the relevant systems were provided. PRSK model can calculate the solubility data better near the critical region.

Ionic liquid (IL) thermodynamic properties, such as density, viscosity and thermal conductivity, are key parameters of chemical engineering processes at variable temperatures and pressures. In this study, we established norm descriptor-based QSPR models to predict IL properties at variable temperatures and pressures. The f-T-P (variation of property f with temperature T and pressure P) models were developed with 9019 data points from 314 ILs for density, 7342 data points from 351 ILs for viscosity and 608 data points from 87 ILs for thermal conductivity. These models had satisfactory statistical results for calculating IL properties. The validation analysis showed that these QSPR models had good stability and predictability. The norm descriptors were universal for predicting IL properties. Moreover, these QSPR models were applied to predict f-T-P model parameters for 16,329 ILs generated by combing the cations and anions in the dataset, which might be valuable and further application in chemical engineering.

Ionic liquids have been becoming new 'green solvent' because of the low saturation vapor pressure, less volatilization and more recycling utilization. Since most ILs are soluble in water, it should be indispensable to evaluate the ecotoxicology effect of ILs on aquatic environment before using them widely. Based on the concept of norm index, a set of norm descriptors were proposed for anions, cations and ILs. The whole IL structure optimization method has been used to build a predictive norm index-based quantitative structure-toxicity relationship model for the toxicity of ILs on Vibrio fischeri. Statistical results indicated that norm descriptors were reliable and robust in expressing the relationship between structural information and toxicity of ILs. Meanwhile, a series of ILs without experimental values were predicted based on this stable QSTR model. The results indicated that for imidazole-based ILs, an increase in the length of substituent in the branch could enhance the toxicity of ILs on Vibrio fischeri, and the branch contains hydroxyl group, double bond or triple bonds might reduce the toxicity of ILs. Results obtained in this present work would be valuable for the molecular design and the toxicity evaluation toward aquatic organism of ILs.

Surface tension and heat capacity are fundamental and crucial properties for ionic liquids (ILs). Most often, separate descriptors based on the cations and anions are used to develop QSPR model, while the effect of ILs is neglected. Thus, in this work, ionic liquids are optimized as a whole; the contributions of not only cations and anions alone but also those of ILs overall are reflected in this treatment. Furthermore, norm descriptors are introduced into the temperature term to correct for temperature effects. Two QSPR models are proposed to predict the surface tension (γ) for the temperature range of 262.89–533.2 K and the heat capacity (Cp) for the temperature range of 188.06–550.00 K. External validation and application domain analysis indicate the predictability and reliability of the models, which demonstrate that these models are thus applicable to calculate γ and Cp for multiple structures in a wide temperature range.