Vapour Phase Synthesis of 2-Methylpyridine and 4-Methylpyridine Over Potassium Salts of 12-Tungstophosphoric Acid

Vapor phase dehydrocyclization reaction of acetaldehyde and ammonia was investigated over K salts of 12-tungstophosphoric acid as catalysts in a continuous flow fixed bed reactor at 350–450℃. The yield of 2-methylpyridine and 4-methylpyridine were found to be in the range of 38.0–64.5%. The 2-methylpyridine and 4-methylpyridine are used for the preparation of insecticides, poultry drugs, cattle drugs and anti-tuberculosis drugs, veterinary analgesics etc. respectively. The reaction conditions such as temperature, contact time, and molar ratio for achieving optimal yield with respect to 2-methylpyridine and 4-methylpyridine were discussed. Catalysts were characterized through BET surface area, FT-IR, XRD and TGA. NH3-TPD studies exhibit the moderate acidity. The morphology of the catalysts was also studied by FESEM

PAHs and potentially toxic elements in the fly ash and bed ash of biomass fired power plants

PAHs and heavy metal chemical fractions were determined in biomass ashes from four power plants that fired coconut, chicken, and wood wastes. All these ashes were alkaline (pH 8.7–12.7). High unburned carbon in the fly ashes (8.3 to 16.9%) indicates incomplete combustion. The major chemical phases were SiO2 – CaO – K2O – MgO followed by Fe2O3 > Al2O3 > SO3 > MnO, with an exception of higher P2O5 (5 – 8.8%) in chicken litter ash. SEMshowed that the FAs have more angular particles,whereas BAs have fused and glassy particles. The contents of B (15– 205 mg/kg), Cu (236 – 481 mg/kg), Cd (13 – 23.2 mg/kg), Ni (50 – 186 mg/kg), and Zn (10 – 400 mg/kg) were relatively higher in the ashes. Most of these elements (except B) were associated with metal oxide and silicates. B is the most mobile element and >75 % of B is present in the available forms. The total PAH content was comparatively lower (0.19 – 12.3 mg/kg), except for wood ash (PAH 193 mg/kg). These ashes have significant amount of plant nutrients and most of the potentially toxic elements are in non-available forms which supports their suitability for soil amendment

Co-gasification of high ash Indian coal-biomass blends in a pilot-scale fluidized bed gasifier

Conventional coal-based technologies are experiencing several disadvantages due to its high ash content as well as a significant amount of greenhouse gas emission. Focus is shifting towards the utilization of renewable resources like biomass. The efficient use of coal and biomass in a clean manner has been the driving force in developing gasification technologies. In the present investigation, an effort has been made to study the gasification performance of selected coal with two types of biomass, namely rice husk and sawdust in different proportions in a pilot-scale bubbling fluidized bed gasifier. Gasification was conducted with a mixture of air and steam at a temperature between 900–950 °C and atmospheric pressure. Mainly, three blends were prepared by adding 10, 20, and 40% of biomass with the selected coal. It was found that up to 40% of biomass loading, gasifier is operated in a trouble-free manner without the formation of tar or any agglomerate by maintaining proper fluidization with smooth and controlled variation in the process parameters like temperature, airflow, and steam flow rate. Due to the synergistic influence between coal and biomass, overall carbon conversion, gas yield, and gas heat value were found to increase with increasing biomass loading

Vapour Phase Synthesis of 2-Methylpyridine and 4-Methylpyridine Over Potassium Salts of 12-Tungstophosphoric Acid

814-820Vapor phase dehydrocyclization reaction of acetaldehyde and ammonia was investigated over K salts of 12-tungstophosphoric acid as catalysts in a continuous flow fixed bed reactor at 350–450℃. The yield of 2-methylpyridine and 4-methylpyridine were found to be in the range of 38.0–64.5%. The 2-methylpyridine and 4-methylpyridine are used for the preparation of insecticides, poultry drugs, cattle drugs and anti-tuberculosis drugs, veterinary analgesics etc. respectively. The reaction conditions such as temperature, contact time, and molar ratio for achieving optimal yield with respect to 2-methylpyridine and 4-methylpyridine were discussed. Catalysts were characterized through BET surface area, FT-IR, XRD and TGA. NH3-TPD studies exhibit the moderate acidity. The morphology of the catalysts was also studied by FESEM

Vapour Phase Synthesis of 2-Methylpyridine and 4-Methylpyridine Over Potassium Salts of 12-Tungstophosphoric Acid

Vapor phase dehydrocyclization reaction of acetaldehyde and ammonia was investigated over K salts of 12-tungstophosphoric acid as catalysts in a continuous flow fixed bed reactor at 350–450℃. The yield of 2-methylpyridine and 4-methylpyridine were found to be in the range of 38.0–64.5%. The 2-methylpyridine and 4-methylpyridine are used for the preparation of insecticides, poultry drugs, cattle drugs and anti-tuberculosis drugs, veterinary analgesics etc. respectively. The reaction conditions such as temperature, contact time, and molar ratio for achieving optimal yield with respect to 2-methylpyridine and 4-methylpyridine were discussed. Catalysts were characterized through BET surface area, FT-IR,XRD and TGA. NH3-TPD studies exhibit the moderate acidity. The morphology of the catalysts was also studied by FESEM

Comparative evaluation of aquatic biomass feedstocks for energy application and potential for extraction of plant nutrients from their ash

Aquatic biomasses have fast growth rate amicable for energy applications. Presence of low melting alkali elements is a major challenge; however they are plant nutrients that enhances the ash utilization potential. The aim of this study was to evaluate aquatic biomasses (Eichornia, Hydrilla, Lemna, and Spirogyra) for potential energy application, and to assess the accumulation of plant nutrients in the ashes obtained at different temperatures (500, 600, 700, 800, and 900 °C). Volatile matter content (wt.% dry basis) was lower in Spirogyra (58.2%) or Hydrilla (56.8%) than Eichornia (68.3%) or Lemna (64.7%), whereas fixed C content (wt. % dry basis) was higher for Eichornia and Lemna (about 11%) and lower for Spirogyra (7.4%) and Hydrilla (1.0%). Carbon content ranged from 25.2 to 37.9%; decreased in the order Eichornia > Lemna > Spirogyra > Hydrilla. Ash content was higher for Hydrilla (42.1%) followed by Spirogyra (34.5%), Lemna (24.0%) and Eichornia (19.9%). FTIR and cluster analysis showed comparable ash characteristics for Eichornia and Lemna; Hydrilla and Spirogyra have typical characteristics. Plant nutrient (except N, and K) contents in the ash increased with increase in temperature. Potassium and phosphorous content was higher in Eichornia and Lemna. Slagging and fouling tendencies could be arranged in the order Hydrilla > Eichornia > Lemna > Spirogyra. Eichornia, Lemna, and Spirogyra feedstock could be used for energy application and the resultant ash has valuable plant nutrients (K and P). Low temperature (600–700 °C) processing is advantageous to conserve plant nutrients in ash