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A glut of inexpensive glycerol has resulted from expanding biodiesel production around the world. This glycerol could be used as a good renewable source to produce hydrogen fuel. Hydrogen production from glycerol via a steam reforming process over Ni/CeO2, Ni/MgO, and Ni/TiO2 catalysts was studied. The catalysts were characterized by using X-ray diffraction, thermogravimetric analysis, BET surface area analysis, metal dispersion, active surface area analysis, and hydrogen temperature programmed reduction. Ni/CeO2 had the highest surface area (67.0 m2/g) followed by Ni/TiO2 (64.9 m2/g) and Ni/MgO (50.2 m2/g). Also, Ni/CeO2 showed the highest metal dispersion (6.14%) compared to Ni/MgO (0.38%) and Ni/TiO2 (0.29%). Effects of reaction temperatures, feed flow rates (FFRs), and water/glycerol molar ratios (WGMRs) on hydrogen selectivity and glycerol conversion were analyzed. Ni/CeO2 was found to be the best performing catalyst compared to Ni/MgO and Ni/TiO2 under the experimental conditions investigated. Ni/CeO2 gave the maximum hydrogen selectivity of 74.7% at a WGMR of 12:1, temperature of 600 °C, and FFR of 0.5 mL/min compared to Ni/MgO (38.6%) and Ni/TiO2 (28.3%) under similar conditions.

Tars have been identified as one of the major impurities associated with biomass gasification fuel gas. Tar buildup can cause blockages, plugging, corrosion, and catalyst deactivation, resulting in serious operational and maintenance problems. Therefore, tar removal is essential to ensure economic and effective fuel gas utilization. This study investigates the catalytic activity of zeolites and nickel supported zeolites for tar removal. Zeolites with varying pore sizes and acidity were tested, to evaluate the effect of pore size and acidity on tar removal. ZY had better catalytic activity due to its larger pore size compared with ZSM5. Catalytic activity of zeolites increased with an increase in the acidity. ZY-5.2, which is more acidic, had better naphthalene conversions compared with ZY-80. Impregnation of nickel on zeolites improved the activity significantly due to the steam reforming ability of nickel. Long-term catalytic activity tests were performed, the results of which showed that nickel-supported ZY-30 and ZY-80 had the best naphthalene conversions, with naphthalene conversions of greater than 99%, followed by nickel-supported ZY-5.2, SiO2/Al2O3, and chabazite. Also, very little loss in activity over a 97 h test period was noticed for nickel-supported ZY-80 and ZY-30, compared with nickel-supported ZY-5.2, SiO2/Al2O3, and chabazite. Characterization of calcined and spent catalysts was performed using X-ray diffraction, thermogravimetric analysis, and surface area analysis, to investigate the lower catalytic activity of nickel-supported ZY-5.2, SiO2/Al2O3, and chabazite. The decreased catalytic activity is attributed to the coke deposition and catalyst surface area.

Effects of the in ovo injection of commercial diluent containing supplemental microminerals (Zn, Mn, and Cu) on hatchability and hatching chick quality variables in Ross × Ross 708 broilers were examined. On 17 d of incubation (doi) eggs were subjected to 1 of 4 treatments using a commercial multi-egg injector. Treatments included non-injected (treatment 1) and diluent-injected (treatment 2) control groups. Those in treatment 3 received diluent containing 0.181, 0.087, and 0.010 mg/mL of Zn, Mn, and Cu, respectively, and those in treatment 4 received diluent containing 0.544, 0.260, and 0.030 mg/mL of Zn, Mn, and Cu, respectively. A total of 1,872 eggs were distributed among 4 treatment groups on each of 6 replicate tray levels. Hatchability of fertile eggs set (HF) was determined on 20.5 and 21.5 doi. On 21.5 doi, HF and mean hatching chick weight (MHW) were determined. One bird from each treatment replicate group was randomly selected, weighed, and necropsied for the extraction of their livers and tibiae. The tibiae fresh and dry weight, length, width, bone breaking strength (BBS), and percentage of bone ash (PBA) were determined. The dry livers were weighed and ashed. Injection treatment had no significant effect on HF at 20.5 doi. However, there was a significant injection treatment effect on HF at 21.5 doi. The HF of eggs at 21.5 doi in treatment 4 was significantly lower than that of the non-injected control group, with treatment 3 being intermediate. Furthermore, there were no significant treatment effects noted for MHW fresh and dry tibia weights, tibia length and width, tibia length to weight ratio, BBS, liver ash content, or percentage of minerals (Ca, P, Mg, Mn, and Zn) in the tibia ash. However, embryos from eggs that received treatment 4 had a significantly higher PBA in comparison to all other treatments. In conclusion, although treatment 4 negatively affected HF, the injection of diluent containing the high micromineral concentration has the potential to improve bone mineralization.