The optimization of heterogeneous catalytic conditions in the direct alkylation of waste vegetable oil

Alkylated waste vegetable oil is a versatile intermediate product in the synthesis of bio-based materials. Heterogeneous catalytic condition with high conversion rate in the direct alkylation of waste vegetable oil was reported and the deactivation mechanism of catalyst was revealed. The total exchange capacity, elemental composition and pyrolysis product of catalyst before and after the alkylation reaction were analysed by back titration, elemental analysis, electrospray ionization mass spectrometry, gas chromatography mass spectrometry and pyrolysis-gas chromatography/mass spectrometry, respectively. The results indicated that the metallic and non-metallic (C, H) elements contents of the catalyst have very much increased with great changes in pyrolysis product and a slight decrease in the total exchange capacity. The formation of insoluble polymers through Diels–Alder cycloaddition between triglycerides was proved to be the major factor causing the dysfunction of the catalytic centre. The metal ions from corrosion of the reactor were the minor factor causing about 2.56% loss of the catalytic centre. Moreover, the catalyst was able to maintain high catalytic efficiency when replacing the raw materials with other waste vegetable oil having low concentration of polyunsaturated fatty acids, which is significant for producing not only the aryl fatty acids derivatives but also the bio-based surfactants.

STUDY OF THE IN VITRO LIPOPROTEIN PLASMASORPTION AND PHYSICOCHEMICAL PROPERTIES OF POLYMERIC SORBENTS WITH SUBSTITUTED AMINO GROUPS

Currently, the plasmasorption method is widely used in clinical practice to remove excessive amounts of metabolites that cause various pathologies. However, the plasmasorbents applied often can give a number of side effects for the patient, such as the blood clotting, the release of dust particles, and the sorption of useful components from the plasma. Besides that, they can be quite expensive. The aim of the work was to create available plasmasorbents with a good hemocompatibility for the lipoprotein adsorption from the plasma. A number of anion exchangers with groups of trimethylamine, monoethanolamine, and triethanolamine were synthesized. For the sorbents obtained, adsorption and physico-chemical properties were investigated. Bulk density, specific volume at swelling, the swelling coefficient in various solvents (water, ethanol, isopropanol, propylene glycol, acetone) were determined and the theoretical calculations of total exchange capacity and crosslinking mass and molar fractions were made. It was found that the best swelling is achieved in propylene glycol. For the sorbents LP27 and LP29, the capacities on triglyceride and lipoprotein fractions and the coefficient of distribution of lipid profile components between the solid and liquid phases were determined. It is shown that both sorbents have good sorption properties, the sample LP29 being quite promising for the lipid profile components extraction. The developed sorbents are assumed to be cheaper than currently used ones as they are synthesized on the basis of commercially available matrix. The results obtained are expected to be useful for further investigations aimed at the modern plasmasorption technology quality improvement.

Contribution of ion-exchange transformation of the adsorbed complex of atmospheric aerosols to the formation of seawater salt composition

Data on the total exchange capacity and composition of the adsorbed complex of terrigenous aerosols generated in arid and semiarid regions of the earth were summarized. It was calculated that as a result of change in composition of the adsorbed complex of aerosols occurring during their interaction with seawater, 2.64–4.86 million tons/year of dissolved Ca2+ are additionally enters into the ocean and 2.45–4.51, 0.73–1.34, and 0.08–0.14 million tons/year of dissolved Na+, K+, and Mg2+, respectively, are removed.

Strong legacy effect of peat composition on physicochemical properties of reclamation coversoil

Incorporation of salvaged peat in soil cover designs for oil sands mine reclamation is a common practice. However, current peat salvage practices do not differentiate between peatland types or the botanical composition of peat. In this study, we characterized the botanical composition of natural peat and coversoil on reclaimed sites and examined the influence of botanical composition on the physicochemical characteristics of reclaimed coversoil. Peat samples were collected from 15 natural peatlands (bog, poor fen, and rich fen) and peat coversoils were sampled from six reclaimed sites in the Athabasca oils sands region. The botanical compositions (Sphagnum, wood Sphagnum, woody, and woody/moss herbaceous) of all samples were determined. We found that natural peatland types had different physicochemical properties, primarily driven by Sphagnum-dominated samples with a high carbon:nitrogen (C:N) ratio and low total exchange capacity (TEC) when compared with samples dominated by more woody/moss herbaceous material. Similarly, we found that coversoil with Sphagnum-dominated peat compared with woody/moss herbaceous peat had lower TEC, pH, and total nitrogen values and higher C:N ratios (∼40 vs. 20 for Sphagnum and woody/moss herbaceous, respectively). Our results indicate that physicochemical properties driven by botanical composition remain in coversoil 5 yr after placement.

Ion exchange resin selection for concentration and purification of uranium leached by sulphuric acid solution

Ion exchange is one of the most popular techniques for recovery and purification of uranium from sulfuric acid leaching solution, especially for recovery of uranium from a low uranium containing solutions. Resins commonly used are strong base or weak base anion resins with amine functional group. The anionic form of resins may be NO3-, Cl- , SO­42- or OH-. The selection of a resin depends on the uranium total exchange capacity, selectivity and the cost. The previous studies often use Amberlite IRA-420 for concentration and purification of uranium solution from Pa Lua sandstone ores. This is a good and suitable resin but high price. To diversify the resins and reduce the costs, instead of IRA-420, the authors tested two commercial resins Indion GS300 (India) and Purolite A400 (UK) in the processing of uranium solution from sandstone ores. The results showed that the uranium total exchange capacity of these resins is only about 80 - 85% over Amberlite IRA-420, but these resins should be able to be used instead of Amberlite IRA-420 due to their low cost and availability in Vietnam.

Sustainability of Organic Fertilization of Macadamia with Macadamia Husk–Manure Compost

A fertilization experiment, started in 1989, evaluated the merits of macadamia husk-manure compost as fertilizer for the production of macadamia. Three fertilization treatments were compared at four sites over 4 years on the MacFarms of Hawaii Honomalino orchard. The treatments were conventional fertilization, a combination of solid and liquid mineral fertilizers annually adjusted by the orchard manager based on leaf and soil analysis; compost only as 5 tons of a macadamia husk-cattle manure compost applied annually between July and October; and compost plus supplemental mineral fertilizers deemed needed by the orchard manager based on leaf and soil analysis. In-shell nut and kernel yield and quality was not significantly different between treatments. Change in leaf nutrient values appears minimum except for slightly lower N at two sites for the compost treatment. Higher Mg was noted for the compost but not the compost plus treatments at the irrigated sites. The effect of compost on the soil nutrient levels was more distinct and may have a delayed and longer term effect. Total exchange capacity of the soil increased, as did soil pH, Ca, Mg, K, and Na. Organic matter increased only at the site with least soil. Extractable soil Fe decreased, this maybe related to the change in pH, but had no consistent effect on leaf Fe. Compost fertilization was not considered sustainable as the cost of compost and its application exceeded conventional fertilization.

The effect of partial exchange of sulphonated macroporous styrene-divinylbenzene copolymers for different ions on their catalytic activity

The catalytic activity of sulphonated macroporous styrene-divinylbenzene copolymers, the exchange capacity of which was neutralized from 30, 50 and 80% by Fe(III) ions and from 30% by Na ions and that of Wofatit Y-37 ion exchanger neutralized from 10% of its total exchange capacity by several transition metal ions and by sodium has been studied in isomerisation of cyclohexene and dehydration of 1-propanol in the gas phase at 130 °C. It was demonstrated that in both reactions transition metal ions exhibit additional effect to the expected neutralization of the polymer acid groups. In the case of cyclohexene isomerization, this effect depends on the degree of crosslinking of polymer mass of the catalyst. Such dependence has not been, however, observed in dehydration of 1-propanol. The type of transition metal ions did not exhibit any significant effect on the catalytic activity of the polymer catalysts studied.

PROPRIETES DE QUELQUES SOLS RICHES EN GRAVIERS DANS LA REGION DE QUEBEC

Twelve soil profiles, developed on gravelly parent material, have been sampled in the region of Quebec City and analyzed. Six profiles are developed on sandstones and shales whilst the six other profiles are formed on shales and mudstones. The shales, and to a lesser extent the sandstones, weathered readily to produce a large percentage of clay. Because of this, many B horizons with significant pyrophosphate-extractable Fe and Al do not meet the criteria for a Podzol B. The coarser than 2 mm material, which ranges in individual horizons from 14 to 82% in the first group of soils and from 0 to 84% in the second group, cannot be ignored as it contributes up to 69% of the total exchange capacity of the soil and therefore is important for the natural fertility of the soils. The differences between the stability of the gravel in air and in water also explain some of the problems in classifying these soils.

Superphosphate and stocking rate effects on a native pasture oversown with Stylosanthes humilis in central coastal Queensland. 3. The balance of native species in the pasture

The percentage frequency of all herbaceous species in a native pasture oversown with S. humilis (T.S.) was measured at the beginning and end of an eight-year grazing experiment. Treatments imposed were three levels of molybdenized superphosphate (nil; 125 kg ha-1 annually; 250 kg ha-1 annually plus an extra 250 kg ha-1 initially) in factorial combination with four stocking rates and two sowing methods for T.S. (ground sowing into spaced cultivated strips or aerial sowing). Stocking rates were gradually increased during the experiment and for the last three years overlapping ranges were used for the three fertilizer levels; the overall range was then from 0.55 to 1.65 beast ha-1. Treatments did not induce any major changes in the proportions of native species in the pasture. Heteropogon contortus remained dominant and its frequency increased in all treatments. Of the total of 113 species recorded, only 18 reached 10 per cent frequency in at least one paddock on one occasion. Several of these showed statistically significant changes in response to treatment, but their relative importance was not greatly changed. Examination of the results by principal co-ordinate and canonical analysis, showed that the first vectors of the two data sets were highly correlated, indicating that the major control on floristic composition was not changed by oversowing with T.S. or by the treatments imposed. Treatment effects dominated in the second and third vectors in the final year. The controlling vector was found to be highly correlated with soil calcium, potassium, total exchange capacity and organic carbon, but the basis for the correlations remains undetermined.

Cation exchange capacity of some tropical soils of Puerto Rico

Data are presented here for the total exchange capacity of 81 soil samples in Puerto Rico and for available cations: Calcium, magnesium, potassium, and sodium, in 30 soil samples. The soils analyzed were representative of the following 13 groups: Rendzina, Wiesenboden, Reddish Brown, Reddish Chestnut, Reddish Prairie, Gray Brown Podzolic, Red and Yellow Podzolic, Reddish Brown Lateritic, Yellowish Brown Lateritic, Ground Water Laterite, Laterite, Lithosols, and Alluvial. Exchangeable bases are also reported for some soils in the Chernozem group. The highest value obtained for total exchange capacity was about 64 milliequivalents per 100 gm. of dry soil for a Rendzina and the lowest was about 2 m.e. for a Laterite. There is a wide difference between the minimum and maximum values of total exchange capacity for the various soil groups. Weathering had been active in the podzolic and more so in the lateritic group. The highest value for total exchangeable bases was over 60 m.e. for an Alluvial soil and the lowest was less than 2 m.e. for a lateritic soil; these contained 80 and 32 percent, respectively, of exchangeable calcium.