scholarly journals Effects of Modification and Co-Aging with Soils on Cd(II) Adsorption Behaviors and Quantitative Mechanisms by Biochar

Author(s):  
Zhuowen Meng ◽  
Shuang Huang ◽  
Zhongbing Lin

Abstract In this study, original rice straw biochar and two KMnO4-modified biochars (pre- and postmodification) were prepared, which were all pyrolysed at 400℃. Premodified biochar had the largest Cd adsorption capacity, strongest acid and solute buffering capacity, which benefited from the increase of carbonate content, specific surface area and the emergence of Mn(II) and MnOx through modification. Original and premodified biochars were then conducted four types of aging process, namely, aging without soil, co-aging with acid (pH=5.00), neutral (pH=7.00) and alkaline (pH=8.30) soils, using an improved three-layer mesh method. The adsorption capacities of modified biochar were always larger than those of original biochar after aging processes. After four aging processes, Cd(II) adsorption capacities were basically in the order of aged biochar without soil > biochar co-aged with alkaline soil > biochar co-aged with neutral soil > biochar co-aged with acid soil, and KMnO4-modified biochar was always better than original biochar after co-aging with soils. The dominant adsorption mechanism of original and premodified biochars (fresh and aged) for Cd(II) was all the precipitation and adsorption with minerals (accounted for 58.55%~85.55%). In this study, we highlighted that biochar remediation for Cd should be evaluated by co-aging with soil instead of aging without soil participation.

2013 ◽  
Vol 726-731 ◽  
pp. 2665-2669 ◽  
Author(s):  
Xian Liu ◽  
Ming Da Liu ◽  
Zeng Gui Gao ◽  
Dan Yang

Effects of two types of biochars from wheat straw (SB) and hard miscellaneous woods (WB), combined with two types of soils on the growth and yield of wheat were evaluated to identify biochar addition to suitable soils on crop yield for accelerating biochar application. Plant growth variables and yields were studied in order to assess the agronomic efficiency of biochar. Our results showed that both biochar additions to an alkaline soil had little or negative effect on plant growth and wheat yield. However, to neutral soil, addition of both biochars could improve plant growth and increase significantly the wheat yield. There were significant differences on effective spikelet, number of seeds, above ground biomass and no significant differences on total spikelet, TKW among different treatments which SB was applied in neutral soil, whereas there were no significant differences on any aforementioned index at application of WB in neutral soil. Further analysis indicated that effect of SB on yield was better than that of WB, and 6% SB and 2% WB were the best for neutral soil respectively.


Holzforschung ◽  
2017 ◽  
Vol 71 (9) ◽  
pp. 759-763 ◽  
Author(s):  
Darrel Nicholas

AbstractSoil chemistry is known to have a major effect on the degradation of treated wood by basidiomycete fungi in laboratory and exterior ground-contact exposures. However, this topic received little attention from a soft-rot (SR) decay perspective. In the present paper, laboratory SR tests were performed with two different types of forest soils, which were also modified. Test samples, made ofPinus glabra(Walt.) (pine) were treated with four commercial copper/organic waterborne preservatives. In addition, soluble or particulate copper and the organic co-biocides quarternary ammonia compound or tebuconazole, were individually examined. After 19 months of soil bed exposure, moderate to severe degradation was observed in all treated samples in both soils. Surprisingly, microscopic examination showed minimal SR decay. Samples in the neutral soil had extensive tunneling bacterial deterioration and the best performance was observed with both copper/quaternary commercial formulations. Samples in the acidic soil appeared to have some white-rot and bacterial deterioration and all four commercial copper/organic formulations showed good statistically equivalent efficacy. For samples treated with only copper, the particulate copper samples performed statistically equivalent or slightly better than amine copper, while samples treated with only the organic quarternary or tebuconazole performed poorly in both soils.


Soil Research ◽  
1992 ◽  
Vol 30 (5) ◽  
pp. 737 ◽  
Author(s):  
IJ Rochester ◽  
GA Constable ◽  
DA Macleod

The literature pertaining to N immobilization indicates that ammonium is immobilized in preference to nitrate. Our previous research in an alkaline clay soil has indicated substantial immobilization of nitrate. To verify the preference for immobilization of nitrate or ammonium by the microbial biomass in this and other soil types, the immobilization of ammonium and nitrate from applications of ammonium sulfate and potassium nitrate following the addition of cotton crop stubble was monitored in six soils. The preference for ammonium or nitrate immobilization was highly correlated with each soil's pH, C/N ratio and its nitrification capacity. Nitrate was immobilized in preference to ammonium in neutral and alkaline soils; ammonium was preferentially immobilized in acid soils. No assimilation of nitrate (or nitrification) occurred in the most acid soil. Similarly, little assimilation of ammonium occurred in the most alkaline soil. Two physiological pathways, the nitrate assimilation pathway and the ammonium assimilation pathway, appear to operate concurrently; the dominance of one pathway over the other is indicated by soil pH. The addition of a nitrification inhibitor to an alkaline soil enhanced the immobilization of ammonium. Recovery of 15N confirmed that N was not denitrified, but was biologically immobilized. The immobilization of 1 5 ~ and the apparent immobilization of N were similar in magnitude. The identification of preferential nitrate immobilization has profound biological significance for the cycling of N in alkaline soils.


2020 ◽  
Vol 1 (2) ◽  
pp. 54-62
Author(s):  
Naser Al Amery ◽  
Hussein Rasool Abid ◽  
Shaobin Wang ◽  
Shaomin Liu

In this study, two improved versions of UiO-66 were successfully synthesised. Modified UiO-66 and UiO-66-Ce were characterised to confirm the integrity of the structure, the stability of functional groups on the surface and the thermal stability. Activated samples were used for removal harmful anionic dye (methyl orange) (MO) from wastewater. Batch adsorption process was relied to investigate the competition between those MOFs for removing MO from aqueous solution. Based on the results, at a higher initial concentration, the maximum MO uptake was achieved by UiO-66-Ce which was better than modified-UiO-66. They adsorbed 71.5 and 62.5 mg g-1 respectively. Langmuir and Freundlich isotherms were employed to simulate the experimental data. In addition, Pseudo first order and Pseudo second order equations were used to describe the dynamic behaviour of MO through the adsorption process. The high adsorption capacities on these adsorbents can make them promised adsorbents in industrial areas.


2014 ◽  
Vol 70 (12) ◽  
pp. 1983-1991 ◽  
Author(s):  
Yuan Yao ◽  
Konstantin Volchek ◽  
Carl E. Brown ◽  
Adam Robinson ◽  
Terry Obal

Perfluorinated compounds (PFCs) are emerging environmental pollutants. Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are the two primary PFC contaminants that are widely found in water, particularly in groundwater. This study compared the adsorption behaviors of PFOS and PFOA on several commercially available adsorbents in water. The tested adsorbents include granular activated carbon (GAC: Filtrasorb 400), powdered activated carbon, multi-walled carbon nanotube (MCN), double-walled carbon nanotube, anion-exchange resin (AER: IRA67), non-ion-exchange polymer, alumina, and silica. The study demonstrated that adsorption is an effective technique for the removal of PFOS/PFOA from aqueous solutions. The kinetic tests showed that the adsorption onto AER reaches equilibrium rapidly (2 h), while it takes approximately 4 and 24 h to reach equilibrium for MCN and GAC, respectively. In terms of adsorption capacity, AER and GAC were identified as the most effective adsorbents to remove PFOS/PFOA from water. Furthermore, MCN, AER, and GAC proved to have high PFOS/PFOA removal efficiencies (≥98%). AER (IRA67) and GAC (Filtrasorb 400) were thus identified as the most promising adsorbents for treating PFOS/PFOA-contaminated groundwater at mg L−1 level based on their equilibrium times, adsorption capacities, removal efficiencies, and associated costs.


2012 ◽  
Vol 189 ◽  
pp. 69-74
Author(s):  
Wei Hu ◽  
Zhen Zhang ◽  
Hui Yun Liu ◽  
Ru Wang

The adsorption behaviors of V(V) and Mo(VI) on the collagen fiber immobilized bayberry tannin (IBT), a new kind of adsorption, were investigated. It was found that at 323K, pH=2.0, the adsorption capacities of V(V) on 0.100g adsorbent was 1.03mmol/g in 100ml of 1.960mmol/L V(V) solution, and that of Mo(VI) was 0.86mmol/g at 323K, pH=4.0, with 100ml of 1.042 mmol/L Mo(VI) solution. The effect of pH on the adsorption capacity of V(V) and Mo(VI) was conspicuous. The adsorption capacity of Mo(VI) decreased with pH increasing, and the maximal adsorption capacity of V(V) was observed at pH4.0. Langmuir equation was used for the description of adsorption isotherms of V(V), while Freundlich equation could be well described that of Mo(VI). The adsorption kinetics of V(V) and Mo(VI) can be well described by the pseudo-second-order-rate model and the adsorption capacities calculated by this model are very close to those experimentally determined. The adsorbent can be regenerated by using 0.1mol/L HCl and 0.02mol/L EDTA in tune as desorption agent after the adsorption of V(V) and Mo(VI). In the desorption process V(V) and Mo(VI) were utilized respectively. These facts implies that the adsorbent can be used for the separation of V(V) and Mo(VI) in aqueous.


2019 ◽  
Vol 6 (3) ◽  
pp. 490-499
Author(s):  
Eri Samah Samah ◽  
Misdawati

Capability of Cellulolytic Degradation (BSD) Bacteria (CDB) to Remodel Organic Waste intoCompost The purpose of this study was to obtain superior cellulolytic bacteria from acid soils as astarter for the degradation of organic waste in the city of Padang by testing the activity of cellulaseenzymes. The method used in the factorial method is the Cellulolytic Degradation Bacteria factorwith the Organic Waste of Padang City. This research was conducted at the Plant PhysiologyLaboratory and the Soil Science Laboratory, Faculty of Agriculture. The research activity was begunby isolating the bacteria from acid soil, followed by testing the enzyme activity of the specific mediumof carboxyl methylcellulose (CMC) medium. Factorial Complete Random Design Method. The firstfactor was selected 3 isolates of cellulolytic bacteria, the second-factor main market organic wasteat of Padang and was two treatments namely unstable sterile (A) and nonsterile (B). The researchresults obtained 6 isolates of cellulolytic bacteria with a clear zone index ≥ 2, namely Km25,Sr. 75, Jm, U-6, G-8, and Km 13, respectively 3.12; 3.04; 3.0; 2.04; 2.00, and 2.04, and used forcomposting organic waste 3 isolates of clear zone bacteria ≥ 3.0 isolates of KM25, Sr75, and JMrespectively 3.12; 3.04; 3.01. Non-sterile organic waste is better than sterile due to the non-sterile,there is the help of battery change from the trash. Conclusion The best composting material is notsterilized, and better bacteria decompose the waste combined with the three isolates KM25, SR75,and JM.


2008 ◽  
Vol 3 (7) ◽  
pp. 1934578X0800300 ◽  
Author(s):  
Jesús Palá-Paúl ◽  
Jaime Usano-Alemany ◽  
A. Cristina Soria ◽  
M. José Pérez-Alonso ◽  
Joseph J. Brophy

The essential oil composition of the aerial parts of four populations of Eryngium campestre has been analyzed by GC and GC/MS. Samples growing in different types of soil were gathered at the same phenological state. A total of 84 compounds have been identified from the different samples under analysis. Qualitative and quantitative differences were found between inflorescences (I) and stems and leaves (SL) of the different populations. The main constituents of the inflorescences were identified as germacrene D (30.3-40.3%), β-curcumene (0.7-22.2%), myrcene (3.0-21.7%) and ( E)-β-farnesene (0.1-19.0%). The type of soil seemed to exert an influence on the chemical composition of the oils of this species. Whereas high concentrations of myrcene were found in the populations growing in acid soil, its concentration was significantly lower in the alkaline populations. β-Curcumene concentration was higher in the populations growing in alkaline soil and was practically absent from the acid soil population. Regarding the stems and leaves, only germacrene D (31.1-42.4%) and myrcene (0.5-23.15) were considered as main constituents, their composition not being affected by the type of soil. However, terpenoid distribution was clearly influenced by the soil, with the population growing in acid soil containing a greater amount of monoterpenes than that of the population growing in alkaline soil. A more exhaustive study needs to be carried out in order to confirm if the biosynthesis of these compounds could be influenced by the availability of Ca2+ in the soil.


2020 ◽  
Vol 12 (20) ◽  
pp. 8335
Author(s):  
Juanhong Wang ◽  
Zhaocheng Zhang ◽  
Dongyang He ◽  
Hao Yang ◽  
Dexin Jin ◽  
...  

Dye effluent has attracted considerable attention from worldwide researchers due to its harm and toxicity in recent years; as a result, the treatment for dye has become one of the focuses in the environmental field. Adsorption has been widely applied in water treatment owing to its various advantages. However, the adsorption behaviors of the new materials, such as the 2D black phosphorus (BP), for pollution were urgently revealed and improved. In this work, BP, black phosphorene (BPR), and sulfonated BPR (BPRS) were prepared by the vapor phase deposition method, liquid-phase exfoliating method, and modification with sulfonation, respectively. The three BP-based materials were characterized and used as adsorbents for the removal of methylene blue (MB) in water. The results showed that the specific surface areas (SSAs) of BP, BPR, and BPRS were only 6.78, 6.92, and 7.72 m2·g−1, respectively. However, the maximum adsorption capacities of BP, BPR, and BPRS for MB could reach up to 84.03, 91.74, and 140.85 mg·g−1, which were higher than other reported materials with large SSAs such as graphene (GP), nanosheet/magnetite, and reduced graphene oxide (rGO). In the process of BP adsorbing MB, wrinkles were generated, and the wrinkles would further induce adsorption. BPR had fewer layers (3–5), more wrinkles, and stronger adsorption capacity (91.74 mg·g−1). The interactions between the BP-based materials and MB might cause the BP-based materials to deform, i.e., to form wrinkles, thereby creating new adsorption sites between layers, and then further inducing adsorption. Although the wrinkles had a certain promotion effect, the adsorption capacity was limited, so the sulfonic acid functional group was introduced to modify BPR to increase its adsorption sites and promote the adsorption effect. These findings could provide a new viewpoint and insight on the adsorption behavior and potential application of the BP-based materials.


1995 ◽  
Vol 35 (1) ◽  
pp. 87 ◽  
Author(s):  
C Tang ◽  
AD Robson

This study examined the effects of inoculation of Bradyrhizobium sp. (Lupinus) on the nodulation and growth of 2 lupin species on an alkaline soil in the field. Plants of L. angustifolius cv. Gungurru (alkaline-sensitive) and L. pilosus Murr. P23030 (alkaline-tolerant) were either not inoculated or inoculated with Bradyrhizobium (strain WU425 or WSM1253) and grown on an alkaline clay, an acid loam, and a limed acid loam. On the alkaline soil, plants of both lupin species without inoculation nodulated poorly and had low nitrogen (N) concentrations in shoots. Inoculation with bradyrhizobia on the alkaline soil greatly increased nodulation and N concentrations in shoots, but nodule number of L. angustifolius was still lower than that on the acid soil. Lupin species differed in growth and nodulation on the alkaline soil, L. pilosus being more tolerant than L. angustifolius. Effects of liming on growth and nodulation were not significant. A survey of a farmer's crop of L. albus cv. Kiev mutant, adjacent to the field trial, showed that poor growth was associated with high soil pH and poor nodulation.


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