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Muhammad Ali Uzair Ali Waqas Asif H. Khoja Nisar Ahmed 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(24):3618-3624
Catalytic and thermal cracking of polypropylene was performed in a batch reactor. Effect of hydrochloric acid activation on kaolin clay, effects of catalysts (acid-activated clays), promoter (5 wt% Ni), and cracking temperatures on the liquid oil yield were investigated. Results show optimized liquid yield (71.9%) obtained at 470°C with kaolin clay activated with 3 M HCl. Acid-activated catalysts were analyzed using XRD and the results reveal the reduction in peaks’ intensities. Weight loss of polypropylene was investigated by thermogravimetric analysis. FTIR and GCMS techniques were employed to analyze the liquid products. 相似文献
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Robert Mokaya William Jones Mary E. Davies Mavis E. Whittle 《Journal of the American Oil Chemists' Society》1993,70(3):241-244
Clays, acid-activated to an optimum level, have been pillared with alumina to give semi-crystalline expanded materials with
surface acidities, pore volumes and average pore diameters generally higher than those of the corresponding pillared materials
derived from a clay matrix not previously acid-activated. The chlorophyll adsorption capacity of the pillared acid-activated
materials is significantly greater than that of pillared, nonactivated clays.
The procedures used in the preparation of these pillared acid-activated clays (i.e., temperature of pillaring, method of drying and calcination temperature) have a significant influence on chlorophyll adsorption
capacity because they influence both the physical and the chemical properties of the final pillared material. This variation
provides a useful means of relating the various properties of the pillared materials to the chlorophyll adsorption capacity.
As a result, a correlation has been demonstrated between adsorption capacity and a combination of pore volume and number of
strong acid sites (of strength pKa < −1.5) present in the pillared material. Optimal adsorbents were obtained from freeze-dried samples prepared by exchange
at 20°C and calcination in air at 500°C. 相似文献
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A series of activated palygorskite clay by HCl with different concentrations was prepared and applied as adsorbents for removal of Cu(II) from aqueous solutions. The effects of contact time, adsorbent dosages and pHs of suspension on the adsorption capacities for Cu(II) were investigated. The results showed that adsorption capacity of activated palygorskites increased with increasing the HCl concentration and the maximum adsorption capacity with 32.24 mg/g for Cu(II) is obtained at 12 mol/L of HCl concentration. The variations in IR spectra and pH of solution after adsorption Cu(II) confirmed that the numerous amount of silanol groups (Si-OH) originated by acid treatment were mainly responsible for Cu(II) adsorption onto acid-activated palygorskite. Kinetic studies indicated that the adsorption mechanisms in the Cu(II)/acid-activated palygorskite system followed the pseudo-second-order kinetic model with a relatively small contribution of film diffusion. Equilibrium data fitted well with Freundlich isotherm model compared to Langmuir isotherm model, indicating that adsorption takes place on heterogeneous surfaces of the acid-activated palygorskite. Adsorption-desorption studies presented that activated palygorskite has lower adsorption and desorption efficiencies using Cu(CH3COO)2 than that of other inorganic copper salts, such as CuSO4, Cu(NO3)2, and CuCl2. 相似文献
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