Fatty methyl ester hydrogenation to fatty alcohol part I: Correlation between catalyst properties and activity/selectivity

Fatty alcohols, derived from natural sources, are commercially produced by hydrogenation of fatty acids or methyl esters in slurry-phase or fixed-bed reactors. One slurry-phase hydrogenation of methyl ester process flows methyl esters and powdered copper chromite catalyst into tubular reactors under high hydrogen pressure and elevated temperature. In the present investigation, slurry-phase hydrogenations of C₁₂ methyl ester were carried out in semi-batch reactions at nonoptimal conditions (i.e., low hydrogen pressure and elevated temperature). These conditions were used to accentuate the host of side reactions that occur during the hydrogenation. Some 14 side reaction routes are outlined. As an extension of this study, copper chromite catalyst was produced under a number of varying calcination temperatures. Differences in catalytic activity and selectivity were determined by closely following side reaction products. Both activity and selectivity correlate well with the crystallinity of the copper chromite surface; they increase with decreasing crystallinity. The ability to follow the wide variety of side reactions may well provide an additional tool for the optimized design of hydrogenation catalysts.     

Continuous wave cavity ring down spectroscopy measurements of velocity distribution functions of argon ions in a helicon plasma

We report continuous wave cavity ring down spectroscopy (CW-CRDS) measurements of ion velocity distribution functions (VDFs) in low pressure argon helicon plasma (magnetic field strength of 600 G, T(e) ≈ 4 eV and n ≈ 5 × 10(11) cm(-3)). Laser induced fluorescence (LIF) is routinely used to measure VDFs of argon ions, argon neutrals, helium neutrals, and xenon ions in helicon sources. Here, we describe a CW-CRDS diagnostic based on a narrow line width, tunable diode laser as an alternative technique to measure VDFs in similar regimes but where LIF is inapplicable. Being an ultra-sensitive, cavity enhanced absorption spectroscopic technique; CW-CRDS can also provide a direct quantitative measurement of the absolute metastable state density. The proof of principle CW-CRDS measurements presented here are of the Doppler broadened absorption spectrum of Ar II at 668.6138 nm. Extrapolating from these initial measurements, it is expected that this diagnostic is suitable for neutrals and ions in plasmas ranging in density from 1 × 10(9) cm(-3) to 1 × 10(13) cm(-3) and target species temperatures less than 20 eV.     

Simplified current minimization control of vector controlled Interior Permanent Magnet motor

This paper presents a simplified current minimizing technique for Interior Permanent Magnet (IPM) motor. This is primarily achieved by utilizing normalized 2D-Look Up Table (LUT) that is parameter independent except for saliency ratio. In addition, torque-flux reference frame is considered for implementation to reduce the complexity generally present in conventional methods utilizing i_ds ? i_qs current reference frame. The proposed algorithm also incorporates both the aspects that lead to field weakening operation, i.e., increase in speed and reduction of dc link voltage. A novel compensation method for incorporating saturation effect is also addressed. The current minimizing technique is analyzed in detail, supported by experimental results.     

Mechanically strong shape memory polyurethane for water vapour permeable membranes

Water vapour permeable polymeric thin films possess significant importance in miscellaneous applications such as packaging, medical devices, controlled‐release systems, electronics and biosensors. In this work, a series of shape memory polyurethanes (SMPUs) were synthesized by a two‐step pre‐polymerization technique with variations in hard to soft segments and molecular weight of macroglycol. DSC, Fourier transform infrared spectra, dynamic TGA and tensile testing were carried out to characterize and evaluate the properties of these synthesized SMPUs. The effect of the soft segment and the molecular weight of macroglycol on the thermal properties, mechanical properties and water vapour permeability of the synthesized SMPUs were investigated to achieve a good water vapour permeable membrane. We found that the synthesized SMPUs demonstrated a good water vapour transmission rate of over 1460 g m^?2 day^–1 as well as robust mechanical properties with tensile strength 19.8 MPa indicating a promising permeable polymeric thin film for many potential applications, especially as protective clothing. © 2018 Society of Chemical Industry     

Modeling traceability information in soybean value chains

Identification of the information to be recorded is the most important requirement for developing an effective traceability system. In this paper, we present a soybean value chain and model the information capture by three links in the chain including the farming, bulk handling and processing sectors. Internal information capture points were identified for each sector and the corresponding traceability information to be recorded was determined. In-depth analyses were conducted for a soybean elevator and an oil and meal processor to determine the importance of traceability information from their perspective. A lot of information is available at different links in the soybean value chain. The method presented here can be used to create a standardized list of data elements that need to be recorded internally or exchanged with other links in the chain. A UML class diagram is developed to represent a method for modeling the product, process, quality and transformation information at any link in the chain. Finally, some suitable technologies for electronic information exchange within the food supply chains are presented.     

Direct oxidation of waste vegetable oil in solid-oxide fuel cells

Solid-oxide fuel cells with ceria, ceria-Cu, and ceria-Rh anode were demonstrated to generate stable electric power with waste vegetable oil through direct oxidation of the fuel. The only pre-treatment to the fuel was a filtration to remove particulates. The performance of the fuel cell was stable over 100 h for the waste vegetable oil without dilution. The generated power was up to 0.25 W cm⁻² for ceria-Rh fuel cell. This compares favorably with previously studied hydrocarbon fuels including jet fuels and Pennsylvania crude oil.     

A cost-effective alkaline multicrystalline silicon surface polishing solution with improved smoothness

In the present paper, intragain surface morphology of multicrystalline silicon (mC-Si) wafer surface of area 3 μm×3 μm polished by the acid-based solution comprising of hydrofluoric (HF), nitric (HNO₃) and acetic (CH₃COOH) acids and new alkaline solution containing sodium hydroxide (NaOH) and sodium hypochlorite (NaOCl) has been studied using an atomic force microscope (AFM). From the roughness and section analysis study of the intergrain surface by the AFM, it is revealed that the NaOH–NaOCl polishing process is quite superior to the existing acid polishing one. Quantitative measurements indicate better smoothness of polished silicon surface after the NaOH–NaOCl treatment as compared with acid polishing. Also process cost per wafer involved in the NaOH–NaOCl polishing process is far lower than that by the acid polishing process along with additional advantageous features of high productivity, environment friendliness and safety. All these factors finally contribute to make the NaOH–NaOCl solution a better polisher for mC-Si surface.     

Development of an on-line optical method for assessment of the bubble size and morphology in aerated food products

The quality of whipped products of the food industry is closely linked to the characteristics of the dispersed gas phase, such as the bubble morphology, the mean bubble size and the uniformity of the bubble size distribution. Here, an on-line method based on imaging techniques was developed for measuring these quantities in food foams manufactured in a continuous foaming device. On-line image acquisition was based on a quartz visualization cell that ensured a continuous renewal of the samples. The mean bubble size and the bubble size distribution were obtained using a semi-automated image analysis procedure. The method was validated on four kinds of aerated food emulsions (ice cream, whipped cream, aerated fresh cheese and a foamed sauce), corresponding to a large range of overrun (30–180%). The σ/d₃₂ ratio of bubble size distributions of dairy foamed emulsions was shown to be nearly constant, regardless of the recipe and of operating conditions.