Ionic liquids for CO2 capture—Development and progress

Innovative off-the-shelf CO₂ capture approaches are burgeoning in the literature, among which, ionic liquids seem to have been omitted in the recent Intergovernmental Panel on Climate Change (IPCC) survey. Ionic liquids (ILs), because of their tunable properties, wide liquid range, reasonable thermal stability, and negligible vapor pressure, are emerging as promising candidates rivaling with conventional amine scrubbing. Due to substantial solubility, room-temperature ionic liquids (RTILs) are quite useful for CO₂ separation from flue gases. Their absorption capacity can be greatly enhanced by functionalization with an amine moiety but with concurrent increase in viscosity making process handling difficult. However this downside can be overcome by making use of supported ionic-liquid membranes (SILMs), especially where high pressures and temperatures are involved. Moreover, due to negligible loss of ionic liquids during recycling, these technologies will also decrease the CO₂ capture cost to a reasonable extent when employed on industrial scale. There is also need to look deeply into the noxious behavior of these unique species. Nevertheless, the flexibility in synthetic structure of ionic liquids may make them opportunistic in CO₂ capture scenarios.     

油酸异丁酯的合成及其对生物柴油降凝效果研究

油酸与异丁醇在离子液体催化剂的作用下发生酯化反应制备油酸异丁酯。研究了催化剂用量、醇酸配比、反应时间、反应温度等对酯化反应转化率的影响,并通过测定凝固点、冷滤点、粘度来考察脂肪酸异丁酯对生物柴油的降凝效果。结果表明,当催化剂用量为2%,醇酸体积比2∶1(摩尔比6.8∶1),反应温度100℃,反应时间3 h,转化率达到95.6%。降凝实验结果表明,把一定量的脂肪酸异丁酯添加到生物柴油中可有效地降低生物柴油的凝固点、冷滤点,改善其低温流动性能。     

低温液体运输车轻量化设计的研究

介绍了低温液体运输车轻量化设计的主要方法,在保温结构上用高真空多层绝热取代传统的珠光砂粉末绝热,在工作方式上,用低温泵排放取代自增压转注,在结构上运用有限元等优化设计方法。文章对国内外同类产品在技术参数上进行了比较。     

A Model for the Estimation of Viscosity of Pure Hydrocarbon Liquids

 

A simple model is developed for the estimation of viscosity of hydrocarbon liquids considering that drag on molecular motion due to thermal energy is balanced by intermolecular attractions. The model equation is validated with National Institute of Standards and Technology data on hydrocarbon liquids (C₃-C₁₀ and C₁₂) considering the effect of molecular shape on drag force. The molecular shape is correlated well with molecular weight of hydrocarbon liquids. The accuracy of the proposed model equation is compared with the correlation. The result showed that the proposed model is more accurate. The proposed model equation predicts the viscosity over a wide range of temperature for C₃-C₂₅ with overall absolute average deviation of 5.13%.     

Ionic liquids for CO2 electrochemical reduction

Electrochemical reduction of CO₂ is a novel research field towards a CO₂-neutral global economy and combating fast accelerating and disastrous climate changes while finding new solutions to store renewable energy in value-added chemicals and fuels. Ionic liquids (ILs), as medium and catalysts (or supporting part of catalysts) have been given wide attention in the electrochemical CO₂ reduction reaction (CO₂RR) due to their unique advantages in lowering overpotential and improving the product selectivity, as well as their designable and tunable properties. In this review, we have summarized the recent progress of CO₂ electro-reduction in IL-based electrolytes to produce higher-value chemicals. We then have highlighted the unique enhancing effect of ILs on CO₂RR as templates, precursors, and surface functional moieties of electrocatalytic materials. Finally, computational chemistry tools utilized to understand how the ILs facilitate the CO₂RR or to propose the reaction mechanisms, generated intermediates and products have been discussed.     

The efficiency and comparison of novel techniques for cell wall disruption in astaxanthin extraction from Haematococcus pluvialis

The efficiency of various techniques pulsed electric field (PEF), ultrasound (US), high‐pressure microfluidisation (HPMF), hydrochloric acid (HCl) and ionic liquids (ILs) for cell wall disruption in astaxanthin extraction from Haematococcus pluvialis was compared. The results indicated that ILs, HCl and HPMF treatment were shown the most efficient for cell disruption with more than 80% astaxanthin recovery. While the cell wall integrity of H. pluvialis cyst cell was less affected by US and PEF treatment. It was found that imidazolium‐based ILs showed the greater potential for cell disruption than pyridinium‐based and ammonium‐based ILs. Among all the ILs examined, 1‐butyl‐3‐methylimidazolium chloride ([Bmim] Cl) exhibited efficient cell disruption and capability of astaxanthin recovery at mild condition (pretreatment with 40% IL aqueous solution at 40 °C, followed by extraction with methanol at 50 °C) without extensive energy consumption and special facility requirement. In addition, recyclability of ILs was excellent.     

Crude Oil Production

Current data on crude oil, field/lease condensate, and natural gas liquids produced from NGL plants. Updated on a monthly basis.     

High-performance sodium polyacrylate nanocomposites developed by using ionic liquid covalently modified multiwalled carbon nanotubes

Ionic liquids grafted with multiwalled-nanotubes (CNT Br/NTf₂), involving hydrophilic bromide salt and hydrophobic bis(trifluoromethanesulphonyl)imide salt, were prepared by amidation, followed by an easy solution-casting method of blending CNT Br/NTf₂ with sodium polyacrylate (PAA) as well as crosslinking agent (XR-100) to form PAA hybrid nanocomposites. The uniform dispersion of CNT Br/NTf₂ were analyzed by TEM. The defects and physical properties of fillers were characterized by Raman spectroscopy, Contact angle test, and TGA. Furthermore, microstructures of hybrid nanocomposites were characterized by SEM, from which it can be found that fillers were homogeneously distributed in the PAA matrix. CNT Br/NTf₂ significantly improved the mechanical properties and tensile fatigue resistance, as well as offered tunable swelling behavior of PAA nanocomposites without wasting too much of thermal stability. This study offers a simple approach to develop multifunctional materials based on ionic liquids covalently modified MWCNTs PAA nanocomposites.     

Highly efficient[C8mim][Cl] ionic liquid accompanied with magnetite nanoparticles and different salts for interfacial tension reduction

The 1-octyl-3-methylimidazolium chloride, [C_8 mim][Cl] ionic liquid(IL) was used as a novel surfactant in n-heptane/water system. The interfacial tensions(IFT) were measured and corresponding variations were investigated. An IFT reduction of 80.8% was appropriate under the IL CMC of about 0.1 mol·L~(-1) and stronger effects were achieved when magnetite nanoparticles and salts were present profoundly under alkaline p Hs.The equilibrium IFT data were accurately simulated with the Frumkin adsorption model. Hereafter, the saturated surface concentration, equilibrium constant and interaction parameter were obtained and their variations were demonstrated. Further, emulsion stability and contact angle of oil/water interface over quartz surface were studied. The oil/water emulsion stability was hardly changed with nanoparticles; however, the stability of oil/water + IL emulsions was significantly improved. It was also revealed that the presence of sodium and calcium chloride electrolytes fortifies the IL impact, whereas sodium sulfate weakens. From dynamic IFT data and fitting with kinetic models, it was found that the IL migration toward interface follows the mixed diffusion–kinetic control model. Consequently, the IL diffusion coefficient and the appropriate activation energy were determined.