The present study is the first quantitative ethnobotanical evaluation of Harighal, an inaccessible and unexplored area of District Bagh Azad Jammu & Kashmir (AJK). The exploration, quantification, ...and comparison of ethnobotanical knowledge among different rural communities of the study area were mainly focused during field survey.
In total, 79 informants (49 men and 34 women) were selected randomly to collect data using a semi-structured questionnaire. Various quantitative indices, including use value, relative frequency of citation, relative importance, fidelity level, and informant consent factor, were employed to evaluate the gathered information. Furthermore, primary data were also compared with twenty-two papers published from adjoining areas.
A total of 150 medicinal plants belonging to 98 genera and 60 families were documented. Asteraceae, Fabaceae, and Rosaceae were the dominant families having 15 species each. Of these, 76 species were indigenous, 74 exotic, 136 were collected in the wild, 10 cultivated, and 4 both wild-collected and cultivated. Herbaceous taxa were the most used life form, and leaves were the most exploited plant part. Decoctions were the most preferred method used in preparation of herbal recipes. Three species viz. Mentha longifolia, Berberis lycium, and Galium aparine had the highest use value (1.05), relative frequency of citation (0.81), and relative importance value (96), respectively. The highest informant consensus factor (ICF) was reported for digestive disorders. Mentha longifolia, Punica granatum, Zanthoxylum alatum, and Olea ferruginea had 100% fidelity values. The Jaccard index revealed that uses of plants were more similar in two neighboring areas, i.e., Pearl Valley and Toli Peer.
Local inhabitants still prioritize herbal medicines as an effective way to treat a wide variety of ailments. Elders and health practitioners of the study area are well aware of indigenous knowledge about medicinal plants, but young people are not much interested in herbal practices. Thus, valuable knowledge about the use of plants is on the verge of decline.
Waste wood biomass as precursor for manufacturing activated carbon (AC) can provide a solution to ever increasing global water quality concerns. In our current work,
derived phosphoric acid-treated ...AC (MA-AC400) was manufactured at a laboratory scale. This novel MA-AC400 was tested for RO16 dye removal performance as a function of contact time, adsorbent dosage, pH, temperature and initial dye concentration in a batch scale arrangement. MA-AC400 was characterized via scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering (DLS) and fluorescence spectroscopy. MA-AC400 is characterized as mesoporous with BET surface area of 293.13 m
g
and average pore width of 20.33 Å. pH
and Boehm titration confirm the acidic surface charges with dominance of phenolic functional groups. The average DLS particle size of MA-AC400 was found in the narrow range of 0.12 to 0.30 µm and this polydispersity was confirmed with multiple excitation fluorescence wavelengths. MA-AC400 showed equilibrium adsorption efficiency of 97.8% for RO16 dye at its initial concentration of 30 mg L
and adsorbent dose of 1 g L
. Thermodynamic study endorsed the spontaneous, favorable, irreversible and exothermic process for RO16 adsorption onto MA-AC400. Equilibrium adsorption data was better explained by Langmuir with high goodness of fit (R
, 0.9964) and this fitness was endorsed with lower error functions. The kinetics data was found well fitted to pseudo-second order (PSO), and intra-particle diffusion kinetic models. Increasing diffusion constant values confirm the intraparticle diffusion at higher RO16 initial concentration and reverse was true for PSO chemisorption kinetics. MA-AC400 exhibited low desorption with studied eluents and its cost was calculated to be $8.36/kg.
Cr(VI) adsorption onto
Eucalyptus camaldulensis
sawdust (ECS) waste was investigated in batch and column reactors. Various parameters, including the adsorbent dose, pH, initial concentration, ...particle size, contact time and temperature were optimized. The maximum adsorption capacity (35.58mg g
-1
, 71.16%) was achieved at pH 2.0. Data fitted well to Freundlich and Halsey’s models (R
2
=0.992), indicating the multilayer adsorption of Cr(VI). It obeys the pseudo-second order kinetics. Endothermic and non-spontaneous nature of Cr(VI) adsorption was observed with positive values of changes in enthalpy (9.83 kJ mol
-1
), and Gibbs-free energy (1.52, 1.38, 1.24, 1.10 and 0.97 kJ mol
-1
), respectively. In this column study, the breakthrough curve time increased from 670 to 1,270min by increasing the bed height from 5 to 15 cm, respectively. Column data was found well fitted to bed depth service time model. Adsorption capacity at 60% breakthrough was 2,443.636mg L
-1
. The study indicates that ECS waste can be a promising adsorbent for Cr(VI) remediation from industrial effluents.
Cr(VI) adsorption was studied for abundantly available low-cost lignocellulosic adsorbents in Pakistan namely, tobacco stalks (TS), white cedar stem (WCS) and eucalyptus bark (EB). Several process ...variables like contact time, adsorbent dose, pH, metal concentration, particle size and temperature were optimized in batch mode. EB showed high Cr(VI) adsorption of 63.66% followed by WCS 62% and TS 57% at pH 2, which is higher than most of the reported literature. Langmuir isotherm (R
= 0.999) was well fitted into the equilibrium Cr(VI) data of EB, suggesting homogeneous active sites and monolayer coverage of Cr(VI) onto the EB surface. Freundlich (R
= 0.9982) isotherm was better fitted to the equilibrium data of TS and WCS, revealing the adsorption sites with heterogeneous energy distribution and multilayer Cr(VI) adsorption. Moreover, the Cr(VI) adsorption of studied adsorbents followed the pseudo-second order kinetic model. Thermodynamic properties were investigated in two temperature ranges, i.e., T
(303–313 K) and T
(313–323 K). TS and EB showed the exothermic at T
and endothermic reactions at T
with entropy controlled adsorption at the solid-liquid interface, and WCS exhibited an opposite thermal trend with decreasing disorderness at solid-liquid interface as temperature rises. Gibbs free energy (ΔG>0) confirmed the non-spontaneous adsorption process for all studied adsorbents.
•Copper removal through bioadsorbents is most attractive and low cost treatment option.•Agricultural, microbial, fungal and forest biomasses as potential bioadsorbents.•The need to switch batch to ...fixed columns studies for field applications.•The importance of understanding the surface chemistry of novel bioadsorbents.•The requirements of low cost and suitable chemical modifications of novel adsorbents.
Copper (Cu2+) containing wastewaters are extensively released from different industries and its excessive entry into food chains results in serious health impairments, carcinogenicity and mutagenesis in various living systems. An array of technologies is in use to remediate Cu2+ from wastewaters. Adsorption is the most attractive option due to the availability of cost effective, sustainable and eco-friendly bioadsorbents. The current review is dedicated to presenting state of the art knowledge on various bioadsorbents and physico-chemical conditions used to remediate Cu2+ from waste streams. The advantages and constraints of various adsorbents were also discussed. The literature revealed the maximum Cu adsorption capacities of various bioadsorbents in the order of algae>agricultural and forest>fungal>bacterial>activated carbon>yeast. However, based on the average Cu adsorption capacity, the arrangement can be: activated carbon>algal>bacterial>agriculture and forest-derived>fungal>yeast biomass. The data of Cu removal using these bioadsorbents were found best fit both Freundlich and Langmuir models. Agriculture and forest derived bioadsorbents have greater potential for Cu removal because of higher uptake, cheaper nature, bulk availability and mono to multilayer adsorption behavior. Higher costs at the biomass transformation stage and decreasing efficiency with desorption cycles are the major constraints to implement this technology.
Dye effluents and their degradation products disrupt the aquatic ecosystem functioning. Corncob was used as a low-cost biosorbent for decolorization of methylene blue (MB) dye. Batch and fixed-bed ...column adsorption were performed by varying temperature, pH, initial dye concentration, adsorbent dose, particle size, and bed height, flow rate and inlet dye concentration, respectively. High MB adsorption capacities of corncob were attained at pH 9, i.e. 45.86 mg g super(-1), 91.7%. Equilibrium data was best described by Langmuir II (R super(2) = 0.999) followed by Freundlich (R super(2) = 0.994) and Halsey (R super(2) = 0.994) isotherm models, which indicates the favorable adsorption of MB dye onto corncob adsorbent. Moreover, chemisorption nature of corncob was confirmed through Dubinin-Radushkevich (E = 16.01 kJ mol super( -1)) and the best fit of pseudo-second-order kinetic model. Thermodynamic studies revealed spontaneous ( Delta G < 0) and endothermic ( Delta H > 0) nature of reaction with increased randomness ( Delta S > 0) at the solid-liquid interface. The breakthrough curves were predicted using Thomas and BDST models. BDST reflected that 2.26 min were required to exhaust 1 cm of the fixed-bed column. MB dye-loaded corncob adsorbent could be regenerated (80%) and reused using 0.1 M acetic acid.
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