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The present study focuses on the use of hydroxyapatite from bovine bones to form a flat porous ceramic support for low-cost ultrafiltration membranes. The chemical composition, structure and particle size of the material and support were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FTIR), thermogravimetry (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and nitrogen adsorption/desorption isotherm (BET) techniques. Bovine bone powder treated at high temperature was mixed with two organic additives and water allowing for extrusion shaping. The membrane prepared with 92 wt.% bovine bone powder and 8 wt.% additives at the sintering temperature of 1,350°C has an average pore size of 20 nm, a high mechanical strength (16.1 Mpa) and high chemical resistance (total weight loss of 1.86%). The ultrafiltration membrane with a stable flux of 470.49 L h-1 m-² bar-1 was applied to treat a pharmaceutical industry effluent resulting in removals of 73% of the chemical oxygen demand, 97% of turbidity, 48.15% of conductivity, 42% of BOD, and more than 99.3% of iron and 75.6% of zinc. This study shows that ultrafiltration membranes prepared from bovine bone are efficient for the treatment of industrial wastewaters. [ABSTRACT FROM AUTHOR]

Introduction Protective plant lipophilic barriers such as suberin and cutin, with their associated waxes, are complex fatty acyl derived polyesters. Their precise chemical composition is valuable to understand the specific role of each compound to the physiological function of the barrier. Objectives To develop a method for the compositional analysis of suberin and associated waxes by gas chromatography (GC) coupled to ion trap-mass spectrometry (IT-MS) using N-( tert-butyldimethylsilyl)- N-methyl-trifluoroacetamide (MTBSTFA) as sylilating reagent, and apply it to compare the suberin of the root and tuber periderm of potato ( Solanum tuberosum). Methodology Waxes and suberin monomers from root and periderm were extracted subsequently using organic solvents and by methanolysis, and subjected to MTBSTFA derivatisation. GC analyses of periderm extracts were used to optimise the chromatographic method and the compound identification. Quantitative data was obtained using external calibration curves. The method was fully validated and applied for suberin composition analyses of roots and periderm. Results Wax and suberin compounds were successfully separated and compound identification was based on the specific (M-57) and non-specific ions in mass spectra. The use of calibration curves built with different external standards provided quantitative accurate data and showed that suberin from root contains shorter chained fatty acyl derivatives and a relative predominance of α,ω-alkanedioic acids compared to that of the periderm. Conclusion We present a method for the analysis of suberin and their associated waxes based on MTBSTFA derivatisation. Moreover, the characteristic root suberin composition may be the adaptive response to its specific regulation of permeability to water and gases. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]