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The catalytic cracking of a blend of raw bio-oil (20 wt %) from black poplar sawdust fast pyrolysis and vacuum gasoil (VGO, 80 wt %) has been studied. The runs have been performed in a riser simulator reactor (RSR) under fluid catalytic cracking (FCC) conditions; that is, 500–560 °C, catalyst to feed mass ratio of 6 gcat (gfeed) –1 on a dry basis, reaction times of 3–10 s and a equilibrated commercial FCC catalyst. The cofeeding effect has been quantified by comparing the yields of product lumps and individual components in the gaseous fraction and gasoline lump in the cracking of VGO, raw bio-oil, and their blend (20% bio-oil/80% VGO), at the same conversion values (60–70 wt %). The cofeeding has a favorable synergy because it promotes the formation of C3–C4 and gasoline (C5–C12) hydrocarbon lumps, attenuating the formation of CO2, CO, and also coke formation. In the cracking of the blend (80% VGO/20% bio-oil) at 70 wt % conversion, a deoxygenation degree of 95 wt % has been obtained, with a total liquid fuel yield of 52.8 wt % and a gasoline yield of 31.6 wt %, with a low oxygenate fraction (<4 wt %) containing carboxylic acids, aldehydes, ketones, and phenols.

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Under natural conditions gold has low solubility that reduces its bioavailability, a critical factor for phytoextraction. Researchers have found that phytoextraction can be improved by using synthetic chelating agents. Preliminary studies have shown that desert willow (Chilopsis linearis), a common inhabitant of the Chihuahuan Desert, is able to extract gold from a gold-enriched medium. The objective of the present study was to determine the ability of thiocyanate to enhance the gold-uptake capacity of C. linearis. Seedlings of this plant were exposed to the following hydroponics treatment: (1) 5 mg Au L(-1) (2.5x10(-5) mol L(-1)), (2) 5 mg Au L(-1) + 10(-5) mol L(-1) NH4SCN, (3) 5 mg Au L(-1) + 5x10(-5) mol L(-1) NH4SCN, and (4) 5 mg Au L(-1) + 10(-4) mol L(-1) NH4SCN. Each treatment had its respective control. After 2 weeks we determined the effect of the treatment on plant growth and gold content by inductively coupled plasma-optical emission spectroscopy (ICP-OES). No signs of shoot-growth inhibition were observed at any NH4SCN treatment level. The ICP-OES analysis showed that addition of 10(-4) mol L(-1) NH4SCN increased the concentration of gold by about 595, 396, and 467% in roots, stems, and leaves, respectively. X-ray absorption spectroscopy (XAS) studies showed that the oxidation state of gold was Au(0) and that gold nanoparticles were formed inside the plants.

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An experimental research of the absorption properties of metal ions onto synthetic hydrogel obtained by solution polymerization of acrylic acid and itaconic acid in presence of N,NЈ-methylenebisacrylamide as crosslinking agent was carried out. The swelling behavior in aqueous salt solutions was studied as a function of divalent cation concentration (Cu 2ϩ , Zn 2ϩ , Ni 2ϩ , Co 2ϩ , Cd 2ϩ , Pb 2ϩ , Hg 2ϩ ) in the external solution ranging from 10 Ϫ5 to 1M, at 25°C. The ability of these hydrogels to bind cations was measured at different pH values and metal ion concentrations.