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Black carbon (BC) is a residue generated by combustion including wildfires and the burning of fossil fuels. It widespread in soils, which comprises 30-50% of total organic carbon in Midwest prairie soils. In this study, we investigated the effects of thermal air oxidation (AO) on the properties and adsorptive functions of a temperature series corncob-derived BC made by pyrolysis anaerobically at 300-700[degrees]C. The original BC has an underdeveloped pore structure with N2 micropore (< 20 [Angstrom]) surface area (SA) less than 10 m2/g, mesopore (20-500 [Angstrom]) SA less than 23 m2/g, and N2 B.E.T. SA less than 50 m2/g. Thermal AO of the BC significantly increased its porosities and SAs, which reached maximums at a AO duration of 30 min and then declined with longer AO time. The moderate- and high-temperature (500-700[degrees]C) BC experienced a much lower mass loss (burn-off) and, interestingly, a greater increase in the porosities and SAs during thermal AO than low-temperature (300-400[degrees]C) BC. The porosities and SAs of BC made by direct thermal AO of corncob were only slightly greater than those of the BC made anaerobically. The results suggest that the thermal AO treatment of corncob or low-temperature BC mainly caused the decomposition of biomass or non-carbonized portion, which did not lead to a significant formation of porosity. On the well-carbonized BC made at 500-700[degrees]C, thermal AO caused the rearrangement of the pore structure and created new pores, especially in the mesopore range., Alemayehu H Bedane * (P1), Xiaojun 'Julia' Zhao (2), Mike Mann (3), and Feng 'Frank' Xiao (1) (1) Civil Engineering, University of North Dakota, Grand Forks, ND, (2) Chemistry, University [...]

The aims of this work were to prepare porous activated carbon from peanut shell by chemical activation using ZnCl2 and study its volatile organic compounds adsorption capacities. The adsorption properties of ethyl on the prepared activated carbon were experimentally determined at different temperatures. The surface textural characteristic of the activated carbon was evaluated by N2 adsorption isotherm measurements. The average BET surface area, pore size, and micro‐pore volume of the prepared activated carbon were 1025 m2/g, 0.70 nm, and 0.37 cm3/g, respectively, with narrow pore size distribution. Higher adsorption capacity of toluene on the activated carbon was observed compared to ethyl benzene and p‐xylene, in particular at low vapour concentration ranges. The experimental isotherm data were also analyzed using the Langmuir, Langmuir‐Freundlich, and multisite Langmuir isotherm model. The Langmuir‐Freundlich and multisite Langmuir model provide the best fit for volatile organic compound adsorption isotherms. In addition, the surface and thermal properties of the activated carbon were also investigated using FT‐IR, Zeta‐potential, and TGA. Overall, the peanut shell activated carbon prepared in this study exhibited comparable surface properties and adsorption performance with the available commercial activated carbons and activated carbons prepared from other various sources reported in other literature. [ABSTRACT FROM AUTHOR]

This work focused on the preparation and characterization of a promising biochar as a novel solid adsorbent towards CO2. The biochar was prepared by catalytic pyrolysis of waste roasted peanut shell in molten salt; it was characterized by means of SEM‐EDS, BET, FTIR, and TGA, followed by determining the adsorption characteristics, such as adsorption capacity, isosteric heat of adsorption, uptake rate, and selectivity via adsorption temperature and gas pressure. The results indicated that the as‐prepared biochar had a rich microporous structure with a peak pore size in the range of 0.69–1.3 nm, and exhibited a good performance of CO2 adsorption with a capacity of 3.8 mmol/g at 273 K and 100 kPa. Moreover, the adsorption selectivity of CO2 over N2, O2, CO, and CH4 was found to be above 12, 11, 8, and 7, respectively. In addition, an interesting phenomenon of an initial increase and then a decrease in the selectivity of CO2/N2 adsorption with increasing gas pressure was experimentally revealed. Preparation of the biochar and its performance for CO2 adsorption. [ABSTRACT FROM AUTHOR]

White birch was stored in the form of bundles, wood chips, and loose slash for a period of one year to examine the changes in biomass fuel properties. The samples were collected at regular quarterly intervals to measure moisture content, CNS content, ash content, and calorific value. Data loggers were also placed into the stored woody biomass to measure the temperature change inside the piles. After the first quarter of the storage period and continuing into the next three months of storage, the moisture content showed the most significant change. The moisture content of the biomass bundles increased from 29 % to above 80 % (db). The moisture content of the pile of wood chips covered with a tarp decreased from 51% to 26% and showed a continuous decline in moisture content to the end of storage period to an average range of 16.5% (db). However, the moisture content of uncovered wood chip pile was observed to continuously increase throughout the storage period, resulting in more than double in magnitude from 59% to 160% (db). The dry matter loss was higher in wood chip piles (8∼27%) than in bundles (∼3%). Among the other properties, there was slightly higher loss of calorific value in wood chips (∼1.6%) as compared to bundles (∼0.7%) at the end of one year. [ABSTRACT FROM AUTHOR]