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Concentrations of emitted pollutants in the atmosphere are influenced by the emission sources and metrological data. In Jordan, diesel fuel is considered to be a main source of SO2, which has a negative impact on the air quality. In this work, the SO2 emitted during the burning of desulfurized diesel fuel using activated carbon is conducted using three types of Artificial Neural Network (Elman, NARX and Feedforward models). In order to accomplish this, the previous experimental work on desulfurization of diesel fuel using two types of activated carbon was adopted. The metrological data involved the average daily temperature (T), relative humidity (RH), wind speed (WS), pressure (P), concentration of Particulate Matter (PM10) and average daily solar radiation (SR) over the period from 2/1/2020 to 30/12/2020. It was found that NARX is the most accurate model in the forecasting process of SO2, followed by Elman and feedforward, which was found to be the least capable model in predicting the SO2 emitted concentration. [ABSTRACT FROM AUTHOR]

Activated carbon (AC), a porous material with high pore volume, attracts increasing attention owing to its potential applications in several fields. The development of a porous structure in AC marginally relies on both the treatment methods and the type of precursor. Thus far, both renewable and nonrenewable precursor sources have been used to synthesize AC with high surface area and pore volume. This study presents the synthesis of AC via physicochemical treatment of waste oil fly ash (OFA), a waste material produced from power plants. The aim was to produce AC by adding surface pores and surface functional groups to the basal plane of OFA. Toward this objective, OFA was first chemically leached/activated with various combinations of H2SO4 and H3PO4, and then physically activated with CO2 at 900 °C. The chemical activation step, synergistically combined with CO2 activation, resulted in an increase of 24 times the specific surface area of the OFA. The maximum increase in surface area was obtained for the sample physicochemically treated with 100% H2SO4. Moreover, the spectroscopic analysis confirmed the presence of acid functional groups after the chemical treatment step. To explore the surface heterogeneity, adsorptive potential distribution in terms of surface energy was also discussed as a function of the surface coverage. Following chemical activation, the OFA surface became heterogeneous. A major portion of the AC showed surface energy in the range of 40-50 erg/K, which was further increased as a result of physical activation at a higher temperature. Thus, the synergism created by physicochemical activation resulted in a material with high surface area and pore volume, and excellent adsorption characteristics. From the findings of this study, it was concluded that OFA is a cost-effective and environmentally benign precursor for the synthesis of AC. [ABSTRACT FROM AUTHOR]

Activated carbon (AC) is made from waste oil fly ash (OFA) which is produced in large quantities from power generation plants through combustion of heavy fuel oil. OFA contains ∼80% carbon that makes it suitable for producing AC by physicochemical treatments using a mixture of HNO 3 , H 2 SO 4 , and H 3 PO 4 acids to remove non-carbonaceous impurities. The acid treated OFA is then activated by CO 2 at 990 °C. The physico-chemical treatments of OFA have increased the surface area from 4 to 375 m 2 /g. Surface morphology and pore volume of AC are characterized by combined SEM and EDX techniques. Elemental analysis shows that sulfur content is reduced from 7.1 wt% in untreated OFA to 0.51 wt% for the treated OFA. The AC is further treated with HNO 3 and NH 4 OH solutions in order to attach the carboxylic and amine groups on the surface, respectively. FTIR characterization is used to confirm the presence of the functional groups on the surface of AC at different stages of its development. The performance of functionalized AC samples is tested for the removal of H 2 S from a synthetic natural gas by carrying out breakthrough experiments. The results from these tests have shown maximum adsorption capacity of 0.3001 mg/g for NH 4 OH functionalized activated carbon with 86.43% regeneration efficiency. The ammonium hydroxide treated AC is found to be more effective for H 2 S removal than acid treated AC as confirmed by breakthrough experiments. The results indicate that the presence of more acidic functionalities on the surface reduces the H 2 S adsorption efficiency from the gas mixture. [ABSTRACT FROM AUTHOR]

Abstract: Asphalt (cheap and available in huge amount in Jordan) was converted into activated carbon powder by chemical treatment with sulphuric and nitric acids at 450°C. The final product was characterized and found effective as adsorbent material. Its cation exchange capacity reaches 191.2meq/100-g carbons when treated with 30wt% acid/asphalt ratio without airflow rate injection and 208meq/100-g carbons when 6.5ml air/min was injected into the surface of the asphalt during activation at the same acid/asphalt weight ratio of 30 and temperature 450°C. The zero point of charge for this product was found to be stable at pH value around 3 in the range of initial pH between 3 and 10. [Copyright &y& Elsevier]

Abstract: Oil fly ash from power generation plants was activated with 30% NH4OH and used for selective adsorption of carbon dioxide from CO2/N2 mixture. The treated samples were characterized for their surface area, morphology, crystalline phase, chemical composition and surface functional groups. Energy dispersive X-ray analysis showed an increase in the carbon contents from 45 to 73wt% as a result of leaching out metal oxides. XRD proved that chemical activation of ash resulted in diminishing of major crystalline phases of zeolite, and other alumino-silicates leaving only quartz and mullite. BET analysis showed an increase in surface area from 59 to 318m2/g after chemical activation and the pore volume increased from 0.0368 to 0.679cm3/g. This increase in pore volume is supported by the results of SEM, where more micropores were opened with well-defined particle sizes and porous structure. The TGA of the treated fly ash showed stability at higher temperature as the weight loss decreased with increasing temperature. For treated ash, the FTIR displayed new peaks of amine functional group. The treated ash was used for the removal of CO2 from CO2/N2 mixture and the maximum adsorption/capturing capacity was found to be 240mg/g. This capacity increases with increase in initial gas concentration, inlet flow rate and temperature suggesting the endothermic nature of the interaction between the gas molecules and the surface of the ash. [Copyright &y& Elsevier]