Economy, environmental assessment and energy conservation for separation of isopropanol/diisopropyl ether/water multi-azeotropes via extractive distillation coupled pervaporation process

This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study.Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol(EG)-EG+H_(2)O process and the 1,3-propanediol(PDO)-IPA+H_(2)O process, the total annual cost(TAC) of the EG-IPA+H_(2)O process decreased by 20.76% and 7.86%(PDO). Compared to the EG-EG+H_(2)O process, the TAC of the PDO-IPA+H_(2)O process reduced 14%, but the global warming potential(GWP) and human toxicity of the PDO-IPA+H_(2)O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H_(2)O process, the EG-IPA+H_(2)O process saves 7.86%(TAC), 9.78%(GWP) and 9.85%(human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H_(2)O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmental assessment and human toxicity, designing cleaner products, controlling waste discharge, and promoting the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical production, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry.

Deactivation mechanism of beta-zeolite catalyst for synthesis of cumene by benzene alkylation with isopropanol

The alkylation of benzene with isopropanol over beta-zeolite is a more cost-effective solution to cumene production. During the benzene alkylation cycles, the cumene selectivity slowly increased, while the benzene conversion presented the sharp decrease due to catalyst deactivation. The deactivation mechanism of betazeolite catalyst was investigated by characterizing the fresh and used catalysts. The XRD, SEM and TEM results show that the crystalline and particle size of the beta-zeolite catalyst almost remained stable during the alkylation cycles. The drop in catalytic activity and benzene conversion could be explained by the TG, BET,NH_3-TPD and GC–MS results. The organic matters mainly consisted of ethylbenzene, p-xylene and 1-ethyl-3-(1-methyl) benzene produced in the benzene alkylation deposited in the catalyst, which strongly reduced the specific surface area of beta-zeolite catalyst. Moreover, during the reaction cycles, the amount of acidity also significantly decreased. As a result, the catalyst deactivation occurred. To maintain the catalytic performance,the catalyst regeneration was carried out by using ethanol rinse and calcination. The deactivated catalyst could be effectively regenerated by the calcination method and the good catalytic performance was obtained.

Simulated annealing-based optimal design of energy efficient ternary extractive dividing wall distillation process for separating benzene-isopropanol-water mixtures

This article investigates the performances of different extractive distillation processes intensified with dividing-wall column for separating benzene-isopropanol-water ternary mixtures.All the processes with ethylene glycol as solvent are optimized with the minimal total annual cost(TAC)as target.In order to get the global optimal solution intelligently,an improved simulated annealing algorithm is adopted,which is programmed in MATLAB and linked to Aspen Plus.The results show that the extractive dividing wall column-solvent(EDWC-S)process consisting of an extractive dividing wall column and a solvent recovery column is the best scheme.It can reduce the TAC by 28.65%and CO_(2) emissions by 32.84% compared to the conventional triple-column extractive distillation process.

Positive Effects of Isopropanol as a Co-Precipitant in Glycerol-3-Phosphate Acyltransferase Crystallization

Glycerol-3-phosphate acyltransferase(GPAT) is considered as the rate-limiting enzyme of glycerolipid synthesis pathway and the core element in lysophosphatidic acid(LPA) synthesis. For understanding its catalytic mechanism, the structural biology study is expected, but is always hindered by obtaining crystals for X-ray diffraction analysis. In this study, a progressive strategy to optimize the crystal of microalgae plastidial GPAT was presented. After the expression and purification of GPAT, the crystals were screened by hanging-drop and only clusters were obtained. The crystals were optimized by adjusting temperature, pH, protein concentration, or precipitant, but little improvement. To improve the interaction between protein and precipitant, the isopropanol was applied as co-precipitant. The qualified crystals formed. It's suggested that isopropanol is critical to affect protein crystallization by altering polyethylene glycol(PEG)-water-protein interaction when PEG serves as precipitant. The resulting crystal diffracted to a resolution of 2.75 ? and belonged to space group P1, with unit-cell parameters a = 50.79, b = 80.09, c = 88.21 ?, and α = 62.85, β = 73.04, γ = 80.53?. This work introduced a new strategy to optimize the crystal of the heterogeneous catalysis enzymes like GPAT and provided the fundamental structural information for the oriented synthesis of marine microalgae glycerolipid.

Hydrothermally Synthesizing Nanospheres of Pd Loaded TiO_2 for Photocatalytically Reducing CO_2 in Isopropanol to Isopropyl Formate

Photocatalytic reduction of CO2 was carried out on villiform spherical catalysts of Pd-TiO2 in isopropanol solution.The catalysts were synthesized by hydrothermal method,their structures,morphologies and optical absorption properties were characterized by X-ray diffraction（XRD）,energy dispersive X-ray spectroscopy（EDS）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,highresolution transmission electron microscopy（HRTEM）and UV-vis absorption spectroscopy（UV-vis）.The photocatalytic activities with different loading amounts and morphologies were evaluated for determining the dominant effect and optimizing the catalyst preparation.Based on a villiform spherical TiO2 with the largest specific surface area in our experiments,we prepared a set of catalysts with various loading amounts of palladium and tested them by bubbling CO2 through the slurry of catalyst and isopropanol.The highest formation rate of isopropyl formate was 276.6μmol/g？cat/h.Eventually we proposed the reaction mechanism.

Isopropanol as Fuel for Small Unmanned Aircraft

Gasoline engines are increasingly popular for use in small unmanned aircraft requiring endurance due to the specific energy of gasoline (47.3 MJ·kg-1) and its cost effectiveness. However, gasoline is volatile and it poses a health hazard. In this work, isopropanol is proposed and investigated as viable fuel for small gasoline engines. Isooctane is used as a benchmark for performance comparison. The field testing reveals that isopropanol offers similar running performance and ease of starting. The maximum output power of isopropanol is surprisingly found to occur at a more advanced ignition timing compared with isooctane. The significant outcome of this study is that isopropanol can readily be used as a replacement fuel for existing engines without the need for any modifications to the ignition module or the engine itself.

Pretreatment of Isopropanol Solution from Pharmaceutical Industry and Pervaporation Dehydration by NaA Zeolite Membranes

有在长度的 80 厘米和在外部直径的 12.8 公里的 NaA 沸石膜被我们与南京 Jiusi 高技术公司合作的研究组准备，中国。在 isopropanol (国际语音学协会) 的 feed 的溶解的无机的盐和 pH 价值的影响 NaA 沸石膜上的答案被调查。两个因素在 NaA 沸石膜的稳定性上展出了强烈影响，这被发现。象 pH 调整和 IPA 溶液的蒸馏那样的一套预告的处理步被建议为 pervaporation 脱水改进稳定性。有 52 m2 膜区域的一台工业规模的 pervaporation 设备被造从工业头孢霉菌素生产使国际语音学协会答案脱水。设备连续地在 368378 K 被操作从有 400500 的 feed 流动率的到不到 2% 的 15%20% 的内容在 37 慳畴慲楴湯愠摮挠浯数楴楴湯攠灸牥浩湥獴? 湡 ? 畦据楴湯污挠 ? 带了的水质量使国际语音学协会答案脱水 ? 瑳摵敩吗？

Synthesis,characterization and application of PVA/ionic liquid mixed matrix membranes for pervaporation dehydration of isopropanol

In this study,polyvinyl alcohol(PVA)–ionic liquid(IL) membranes were prepared for the separation of isopropyl alcohol(IPA)–water azeotropic mixtures by pervaporation.PVA-IL composite membranes were prepared by simple solvent evaporation method using four ILs,viz.,1-n-butyl-3-methylimidazolium chloride(BMIMCl),1-hexyl-3-methylimidazolium chloride(HMIMCl),1-hexyl-3-methylimidazolium tetra fluoroborate(HMIMBF4) and 1-octyl-3-methylimidazolium chloride(OMIMCl).Three ILs were used to study the effect of alkyl chain on the pervaporation performance.The study had focused on the effect feed water concentration from 10%–40%and effect of feed temperature from 50–80°C.Physiochemical properties of all the membranes were studied using Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM) and contact angle measurement.The Arrhenius activation energies for permeation were estimated to be in the range 4–12 kJ·mol-1 from the temperature dependent permeation values.

THE FABRICATION OF CARBON AEROGELS BY GELATION IN ISOPROPANOL WITH BASIC CATALYST

A new method for the fabrication of carbon aerogels is reported in this paper. Resorcinol and furfural were gelated in isopropanol with basic catalysts and then dried directly under isopropanol supercritical condition, followed by carbonization under nitrogen atmosphere. The bulk densities of carbon aerogels obtained are in the range of 0.21g/cm3~0.27g/cm3 and the sizes of the interconnected carbon nano-particles are in the range of 20nm^30nm. All of the aerogel samples exhibit high BET surface areas in the range of 730m2/g^900m2/g. The bulk density, micro-pore volume, meso-pore volume and meso-pore diameter can be controlled by gelation conditions such as R/I ratio and R/C ratio.

Transport Process of Isopropanol Aqueous Solution by Pervaporation

To study the transport process of isopropanol aqueous solution by pervaporation, the transport model of isopropanol and that of water at 323 K in polyvinyl alcohol(PVA) membrane were obtained in this paper. Theoretical predictions agreed well with the experimental results. The interactional parameter between water and PVA membrane is less than that between isopropanol and PVA membrane, which shows that water is preferentially dissolved in PVA membrane. The plasticizing coefficient and diffusion coefficient at infinite dilution of water are larger than those of isopropanol, which shows that the dissolution and permeation in PVA membrane of water are greater than those of isopropanol. Both the interactional parameter between water and isopropanol in the membrane and that in feed rise with the increase of isopropanol content in feed, which shows that the larger isopropanol content is, the higher selectivity of the membrane is and the more remarkable separation effect of pervaporation is.

Efficient flexible perovskite solar cells and modules using a stable SnO_(2)-nanocrystal isopropanol dispersion

The outstanding advantages of lightweight and flexibility enable flexible perovskite solar cells(PSCs)to have great application potential in mobile energy devices.Due to the low cost,low-temperature processibility,and high electron mobility,SnO_(2) nanocrystals have been widely employed as the electron transport layer in flexible PSCs.To prepare high-quality SnO_(2) layers,a monodispersed nanocrystal solution is normally used.However,the SnO_(2) nanocrystals can easily aggregate,especially after long periods of storage.Herein,we develop a green and cost-effective strategy for the synthesis of high-quality SnO_(2) nanocrystals at low temperatures by introducing small molecules of glycerol,obtaining a stable and well-dispersed SnO_(2)-nanocrystal isopropanol dispersion successfully.Due to the enhanced dispersity and super wettability of this alcohol-based SnO_(2)-nanocrystal solution,large-area smooth and dense SnO_(2) films are easily deposited on the plastic conductive substrate.Furthermore,this contributes to effective charge transfer and suppressed non-radiative recombination at the interface between the SnO_(2) and perovskite layers.As a result,a greatly enhanced power conversion efficiency(PCE)of 21.8%from 19.2%is achieved for small-area flexible PSCs.A large-area 5 cm×5 cm flexible perovskite solar mini-module with a champion PCE of 16.5%and good stability is also demonstrated via this glycerol-modified SnO_(2)-nanocrystal isopropanol dispersion approach.

Al-doped ZnO/WO_(3) heterostructure films prepared by magnetron sputtering for isopropanol sensors

Metal oxide semiconductors(MOSs) are ideal sensing materials for detecting volatile organic compounds due to their low cost, diversity, high stability, and ease of production. However, it remains a grand challenge to develop the MOSs-based gas sensors for sensing isopropanol with desired performance via a simple, effective,and controllable method. Herein, we reported the preparation of the Al-doped Zn O(AZO)/WO_(3) heterostructure films by directly depositing the AZO coating onto the WO_(3) coating using a strategy of magnetron sputtering. The AZO/WO_(3) heterostructure films were constructed by numbers of irregular nanoparticles that were interconnected with each other. The AZO/WO_(3) heterostructure films-based gas sensors exhibited excellent isopropanolsensing performance with high response, promising selectivity, low detection limit, fast response rate, wide detection range, and ideal reproducibility. The promising isopropanol-sensing performance of the AZO/WO_(3) heterostructure films arises mainly from their high uniformity, unique microstructures with high surface roughness,and the construction of the heterostructure between the AZO and WO_(3) coatings. This work provides a versatile approach to prepare the MOSs-based heterostructure films for assembling the gas sensors.

Swallowing Difficulties,Oral Symptoms,and Nutrition in Long-Term Care Elderly Residents-A Secondary Publication

Oral health is often impaired in people living in residential care.In older people,poor oral health is associated with functional deficits,multiple sclerosis,and memory disorders.Keeping one’s teeth healthy throughout life would promote both oral health and general health.Biting and swallowing problems in older people are also linked to oral health,limiting eating activities and requiring diet changes to softer foods that are easy to chew and swallow.This may limit dietary diversity and adequate nutrient intake.Although eating-related chewing and swallowing problems are common in institutionalized residents,they are often addressed too late,when the resident is already malnourished.Nutrition in nursing and retirement homes has been the subject of various studies since the 2000s.However,studies on swallowing and chewing difficulties are scarce and their link to adequate nutrient intake has received lesser attention[6,7].

NiO nanoparticles-decorated ZnO hierarchical structures for isopropanol gas sensing

In this paper,a three-dimensional(3D)hierar-chical ZnO structure consisting of nanosheets modified with ultrafine NiO particles was synthesized via a facile two-step chemical precipitate method.Various techniques characterized the as-synthesized ZnO/NiO composites and pure ZnO.The p-NiO/n-ZnO junctions formed between adjacent ZnO and NiO nanoparticles,improving the gas sensing performance.The ZnO/NiO composite with the Ni:Zn atomic ratio of 7.42:100 exhibited the best iso-propanol sensing properties.Compared to pure ZnO,it showed high selectivity and sensitivity(R_(a)/R_(g)=221.3 toward 400×10^(-6)isopropanol),fast response rate(less than 10 s),short recovery time,and simultaneously low operating temperature.Also,the ZnO/NiO composite exhibited a wide sensing range(1×10^(-6)-1000×10^(-6))to isopropanol and processed good long-term stability.The experimental results suggested the potential application in fabricating efficient isopropanol sensors using this ZnO/NiO composite.The enhanced isopropanol sensing mech-anism is also discussed in charge transfer between heterojunctions,surface area,and surface defects.

温和条件下糠醇加氢催化剂性能的研究

本文选用Ru/C、Ru/Al_(2)O_(3)、Pd/C、Pd/Al_(2)O_(3)、Pt/C、雷尼镍等催化剂用于糠醇加氢的釜式反应研究。研究发现,Ru/C催化剂在糠醇加氢制备四氢糠醇的反应中具有良好的反应性能。研究了在Ru/C催化剂作用下溶剂、反应温度、氢气压力、反应时间、催化剂的用量等因素对反应的影响,并对工艺条件进行了优化。得到最佳工艺条件:异丙醇作溶剂,反应温度为60℃、氢气压力为3 MPa、反应时间为6 h,原料与催化剂的质量比为20:1,糠醇的转化率达到100%,四氢糠醇的选择性大于95%。

Facile synthesis of Ni-doped SnO_(2) nanorods and their high gas sensitivity to isopropanol

In this work,pure SnO_(2) and Ni-doped SnO_(2) nanorods were synthesized through a one-step template-free hydrothermal method and then used to detect isopropanol.Sensors fabricated with the Ni-doped SnO_(2) nanocomposites showed the best gas sensing performance when the Ni doping amount was 1.5 mol.%.The response reached 250 at 225℃,which was approximately 8.3 times higher than that of the pure SnO_(2) nanorods.The limit of detection for isopropanol was as low as 10 ppb at the optimum working temperature.In addition,it also displayed good selectivity and excellent reproducibility.It is believed that the enhanced isopropanol sensing behavior benefit from the increased oxygen defects and larger specific surface area by Ni doping.

间歇式水热合成制备丝光沸石膜及其异丙醇脱水应用

采用市售廉价大孔α-Al_(2)O_(3)管作为基质材料,通过热浸渍法在管外表面涂敷晶种,随后在无模板剂体系下,利用新型的间歇式水热合成法制备丝光沸石膜。对比了传统加热和间歇式加热对丝光沸石膜形貌、结构及渗透蒸发异丙醇脱水分离性能的差异。考察了合成液中Na_(2)O/SiO_(2)、SiO_(2)/Al_(2)O_(3)和NaF/SiO_(2)物质的量之比在间歇式水热合成下对丝光沸石膜的影响。研究结果表明,当合成液中Na_(2)O/SiO_(2)、SiO_(2)/Al_(2)O_(3)和NaF/SiO_(2)物质的量之比分别为0.24、16.7和0.25时,制备的丝光沸石膜渗透蒸发异丙醇脱水分离性能最佳,在75℃下,对异丙醇/水(9:1,w/w)的渗透通量达5.60 kg·m^(-2)·h^(-1),水对异丙醇的分离因数大于10000。

离子液体+正己烷+异丙醇液液相平衡数据的测定及关联

通过COSMO-RS模型筛选出1-乙基-3-甲基咪唑三氟乙酸盐([EMIM][TFA])、1-乙基-3-甲基咪唑二氰胺盐([EMIM][DCA])、1-乙基-3-甲基咪唑磷酸二乙酯([EMIM][DEP])三种离子液体作为萃取剂分离正己烷-异丙醇体系。在303.15 K、101.3 kPa下,测定正己烷+异丙醇+[EMIM][DCA]/[EMIM][TFA]/[EMIM][DEP]的三元液液相平衡实验数据,通过计算得出选择性与分配系数,分析离子液体各自的分离性能。通过Othmer-Tobias,Bachman,Hand方程对实验数据进行一致性检验。采用Aspen Plus v11流程模拟软件中NRTL模型进行数据关联拟合,获得均方根偏差(RMSD)和二元交互作用参数。模拟结果表明,选择性与分配系数均大于1,说明三种离子液体均可作为萃取剂;方程的回归系数均大于0.95,说明实验数据可靠;得到RMSD均小于3%,说明模拟计算数据能较好地关联实验数据。

基于异丙醇溶剂热合成四方相BaTiO_(3)工艺探索及机理研究

以Ba(OH)_(2)·8H_(2)O和Ti(OC_(4)H_(9))_(4)为原料、异丙醇(IPA)为溶剂,通过溶剂热法合成富四方相纳米钛酸钡(BTO)粉体,研究了钡钛比、体系pH值、溶剂热温度及时间等因素对制备高四方性纳米BTO粉体的影响,利用X射线衍射和扫描电镜等表征方法研究了IPA在溶剂热制备BTO过程中的作用机理。结果表明,溶剂热工艺合成过程中,IPA会优先提供一定的—OH以促进Ti(OC_(4)H_(9))_(4)的水解,生成TiO_(6)八面体并与Ba^(2+)连接。在低碱度环境中,经相转变、小颗粒溶解与重结晶等过程逐步转变为形貌规整的四方相BTO。钡钛比1.6、体系pH值10、溶剂热温度220℃、时间24 h、煅烧温度950℃、煅烧时间2 h时制备的富四方相纳米BTO粉体分散均匀、形貌规整,呈四方形或近四方形,c/a值达1.009 4,平均粒径为124 nm。