Sphagnum Peat Moss Research Articles

Restricting Phosphorous Can Manage Growth and Development of Containerized Sweet Basil, Dill, Parsley, and Sage

The objective of this research was to quantify the effects of phosphorous (P) concentrations on the growth, development, and tissue mineral nutrient concentrations of four popular culinary herbs commonly grown in containers. Seedlings of sweet basil (Ocimum basilicum ‘Italian Large Leaf’), dill (Anethum graveolens ‘Fernleaf’), parsley (Petroselinum crispum ‘Giant of Italy’), and sage (Salvia officinalis) were individually transplanted to 11.4-cm-diameter containers filled with soilless substrate comprising canadian sphagnum peatmoss and coarse perlite. Upon transplanting and throughout the experiment, seedlings were irrigated with solutions containing 0, 5, 10, 20, or 40 mg·L−1 P; all other macro- and micronutrient concentrations were the same across P concentrations. Plants were grown for 4 weeks in a greenhouse; after that time, data were collected. Relationships between height and width and P concentrations were nonlinear for all four species; height and width increased as P increased to more than 0 mg·L−1 until the species-specific maxima; after that time, no further increase occurred. The same trend was observed for the branch length of sweet basil and sage, and for internode length, leaf area, and shoot dry mass of all four species. Although visible P deficiency symptoms were observed for plants provided with 0 mg·L−1 P, there were no signs of P deficiency for plants provided with ≥5 mg·L−1 P, even though tissue P concentrations were below the recommended sufficiency ranges. As a result of this research, containerized sweet basil, dill, parsley, and sage can be provided with 5 to 10 mg·L−1 P during production to limit growth and produce plants without visible nutrient deficiency symptoms that are proportional to their containers.

The Use of Dewpoint Hygrometry to Measure Low Water Potentials in Soilless Substrate Components and Composites

Plant water availability in soilless substrates is an important management consideration to maximize water efficiency for containerized crops. Changes in the characteristics (i.e., shrink) of these substrates at low water potential (<−1.0 MPa) when using a conventional pressure plate-base can reduce hydraulic connectivity between the plate and the substrate sample resulting in inaccurate measures of water retention. Soilless substrate components Sphagnum peatmoss, coconut coir, aged pine bark, shredded pine wood, pine wood chips, and two substrate composites were tested to determine the range of volumetric water content (VWC) of surface-bound water at water potentials between −1.0 to −2.0 MPa. Substrate water potentials were measured utilizing dewpoint hygrometry. The VWC for all components or composites was between 5% and 14%. These results were considerably lower compared to previous research (25% to 35% VWC) utilizing conventional pressure plate extraction techniques. This suggests that pressure plate measurements may overestimate this surface-bound water which is generally considered unavailable for plant uptake. This would result in underestimating available water by as much as 50%.

Comparison of Water Capture Efficiency through Two Irrigation Techniques of Three Common Greenhouse Soilless Substrate Components

Substrate wettability is an important factor in determining effective and efficient irrigation techniques for container-grown crops. Reduced substrate wettability can lead to lower substrate water capture, excessive leaching and poor plant growth. This research examined substrate water capture using surface and subirrigation under three initial moisture contents (IMC). Sphagnum peat moss, coconut coir, and pine bark were tested at IMCs of 67% 50%, and 33%. Substrate water capture was influenced by both IMC and irrigation technique. Surface irrigation increased the water capture of coir and peat, regardless of IMC, whereas IMC influenced pine bark water capture more than irrigation method. Surface-irrigated coir at or above 50% IMC provided the greatest water capture across all treatments. The first irrigation had the highest capture rate compared to all other events combined. Container capacities of pine bark and coir were unaffected by IMC and irrigation type, but the CC of peat was less by ~ 40% volumetrically under low IMC conditions. Coir, had the greatest ability to capture water, followed by pine bark and peat, respectively. Moisture content, irrigation type and component selection all influence the water capture efficiency of a container substrate.

Softening of tap water via calcium removal using sphagnum peat moss sorbent by batch and flow-through approaches

ABSTRACTThe Gaza Strip experiences a water crisis of persistent qualitative and quantitative deterioration in regard to groundwater. There is a low recharging rate of the aquifer because of the low seasonal rainfall, the fast expansion of the urban area, and the high seawater intrusion along the narrow coastal Gaza Strip. Thus, the extremely hard water reduces the performance of the reverse osmosis desalination household units and causes membrane fouling. Sphagnum peat for removal of calcium from water was investigated applying batch and flow-through approaches. Fast calcium removal was demonstrated.

ИССЛЕДОВАНИЕ КАЧЕСТВЕННЫХ ХАРАКТЕРИСТИК УНИВЕРСАЛЬНЫХ СОРБЕНТОВ, ИСПОЛЬЗУЮЩИХСЯ НА УФИМСКИХ НПЗ

Determined the efficiency of use and capacity of oil absorption of natural large-dispersed hydrophilic isotropic-porous universal sorbent “Canadian Sphagnum Peat Moss” and organic finely-dispersed coarse hydrophilic isotropic-porous sorbents: “Profsorb”, “Lessorb”, “STsN-2” in relation to various environments and products of oil refining. The quantitative analysis method was carried out according to GOST 33627-2015. The obtained results showed that the high absorption capacity when bottling gasoline, kerosene and drying oil sorbents “Lessorb” and “STsN-2”, when bottling oil sorbents No. 1, “Lessorb” and “STsN-2”, when bottling benzene, p-xylene and o-xylene – sorbents “Profso”, “STsN-2”.

Response of Calceolaria ×herbeohybrida Cultivars to Substrate pH and Corresponding Leaf Tissue Nutrient Concentration Effects

Calceolaria (Calceolaria ×herbeohybrida) is a flowering potted greenhouse crop that often develops upper-leaf chlorosis, interveinal chlorosis, and marginal and leaf-tip necrosis (death) caused by cultural practices. The objectives of this research were to 1) determine the optimal incorporation rate of dolomitic and/or hydrated lime to increase substrate pH; 2) determine the influence of the liming material on substrate pH, plant growth, and leaf tissue nutrient concentrations; and 3) determine the optimal substrate pH to grow and maintain during calceolaria production. Sphagnum peatmoss was amended with 20% (by volume) perlite and incorporated with pulverized dolomitic carbonate limestone (DL) and/or hydrated limestone (HL) at the following concentrations: 48.1 kg·m−3 or 144.2 kg·m−3 DL, 17.6 kg·m−3 DL + 5.3 kg·m−3 HL, or 17.6 kg·m−3 DL + 10.6 kg·m−3 HL to achieve a target substrate pH of 4.5, 5.5, 6.5, and 7.5, respectively. Calceolaria ‘Orange’, ‘Orange Red Eye’, ‘Yellow’, and ‘Yellow Red Eye’ were grown in each of the prepared substrates. For all cultivars, substrate solution pH increased as limestone incorporation concentration and weeks after transplant (WAT) increased, although to different magnitudes. For example, as limestone incorporation increased from 48.1 kg·m−3 DL to 17.6 kg·m−3 DL + 10.6 kg·m−3 HL, substrate solution pH for ‘Orange’ calceolaria increased from 4.1 to 6.9 to 4.8 to 7.2 at 2 and 6 WAT, respectively. Substrate solution electrical conductivity (EC) and growth indices were not influenced by limestone incorporation, but total plant dry mass increased. Few macronutrients and most micronutrients were influenced by limestone incorporation. Leaf tissue iron concentrations for ‘Orange’, ‘Orange Red Eye’, ‘Yellow’, and ‘Yellow Red Eye’ calceolaria decreased by 146%, 91%, 71%, and 84%, respectively, when plants were grown in substrates incorporated with increasing limestone concentrations from 144.2 kg·m−3 DL to 17.6 kg·m−3 DL + 10.6 kg·m−3 HL (pH 6.5–6.9). Therefore, incorporating 144.2 kg·m−3 DL into peat-based substrates and maintaining a pH <6.5 will avoid high pH–induced Fe deficiency and prevent upper-leaf and interveinal chlorosis.

Substrate Volumetric Water Content Controls Growth and Development of Containerized Culinary Herbs

There are no chemical plant growth retardants that may be used on containerized culinary herbs intended for consumption. Our objective was to quantify the effect of substrate moisture content on the growth of four commonly produced culinary annual herbs grown in containers in the greenhouse. Seedlings of basil (Ocimum basilicum L.), dill (Anethum graveolens L.), parsley (Petroselinum crispum (Mill.) Fuss), and sage (Salvia officinalis L.) were transplanted into 11.4 cm diameter containers filled with commercial soilless substrate comprising (by vol.) 75% sphagnum peat moss and 25% coarse perlite and amended with 3.0 kg·m−3 of controlled-release fertilizer. After the containers were thoroughly irrigated to container capacity, plants were placed into a sensor-controlled irrigation system, which maintained substrate volumetric water content (VWC) at 0.15, 0.28, 0.30, 0.38, or 0.45 m3·m−3. Chlorophyll fluorescence, photosynthesis, stomatal conductance, and transpiration were measured 27 d after initiating treatments, and the results showed that chlorophyll fluorescence of parsley and photosynthesis of basil increased as substrate VWC increased from 0.15 to 0.45 m3·m−3; the remaining parameters for basil, parsley, and sage were unaffected. Additionally, height, width, leaf area, and shoot dry mass of basil, dill, parsley, and sage increased as substrate volumetric water content increased from 0.15 to 0.45 m3·m−3. Our results show that growth of basil, dill, parsley, and sage can be promoted or inhibited by providing or withholding water, respectively, with no signs of stress or visual damage resulting from reduced substrate volumetric water content. Therefore, restricting irrigation and substrate volumetric water content is an effective nonchemical growth control method for containerized culinary herbs grown in peat-based substrate.

Ultrafast remediation of lead-contaminated water applying sphagnum peat moss by dispersive solid-phase extraction

ABSTRACT Lead poisoning, correlated to the high blood lead levels among the children of the Gaza Strip, is another severe problem for Palestinians. The paper reports a cost-effective and time-effective remediation by sphagnum moss, which can remove lead from aqueous solution through dispersive solid-phase extraction. The optimum conditions of adsorption such as equilibrium time, pH, adsorbate initial concentration and adsorbent mass were investigated. In conclusion, a cost-effective and ultrafast lead uptake of ~95% was established in 60 s as adsorption-equilibrium contact time. Thus, a design of flow-through remediation unit for lead removal from real-life contaminated water would provide healthy outflow water. Moreover, regeneration and reuse of sphagnum in lead removal is advantageous for less developed economies with a problem of lead pollution in their water.

Polyhydroxyalkanoates production from methane emissions in Sphagnum mosses: Assessing the effect of temperature and phosphorus limitation

The isolation of highly efficient methanotrophic communities is crucial for the optimization of methane bioconversion into products with a high market value such as polyhydroxyalkanoates (PHA). The research here presented aimed at enriching a methanotrophic consortium from two different inocula (Sphagnum peat moss (Sp) and Sphagnum and activated sludge (M)) able to accumulate PHA while efficiently oxidizing CH4. Moreover, the effect of the temperature and phosphorus limitation on the biodegradation rate of CH4 and the PHA accumulation potential was investigated. Higher CH4 degradation rates were obtained under P availability at increasing temperature (25, 30 and 37 °C). The biomass enriched from the mixed inoculum always exhibited a superior biodegradation performance regardless of the temperature (a maximum value of 84.3 ± 8.4 mg CH4 h−1 g biomass−1 was recorded at 37 °C). The results of the PHB production showed that phosphorus limitation is required to promote PHB accumulation, the highest PHB content being observed with the Sphagnum inoculum at 25 °C (13.6 ± 5.6%).The differential specialization of the microbial communities depending on the enrichment temperature supported the key role of this parameter on the results obtained. In all cases after the completion of the enrichment process and of the P limitation tests, Methylocystis, a type II methanotroph known for its ability to accumulate PHA, was the genus that became dominant (reaching percentages from 16 to 46% depending on the enrichment temperature). Thus, the results here obtained demonstrated for the first time the relevance of the temperature used for the enrichment of the methanotrophic bacteria to boost PHA production yields under P limiting condition, highlighting the importance of optimizing culture conditions to improve the cost-efficiency of bioprocesses based on using methane as the primary feedstock for the PHA industrial market.

Assessment of thermally treated sphagnum peat moss sorbents for removal of phenol red, bromothymol blue and malachite green from aqueous solution

ABSTRACTNine thermally treated sphagnum sorbents were investigated for dye removal of phenol red, bromothymol blue and malachite green from aqueous solutions. These sorbents were analysed for dye removal applying the optimum adsorption conditions with respect to shaking speed, equilibrium contact times and solution pH. The analysis applied the non-treated sphagnum sample. Furthermore, these sorbents were analysed by thermogravimetric analysis and infrared spectroscopy. Hence, sphagnum sorbents of mild or no thermal treatment were shown to remove very well both cationic and anionic dyes. This experiment has fortunately identified an economic method of low energy consumption for the treatment of dye effluents by sphagnum.

Adsorptive-removal of Bromothymol Blue as Acidic-dye Probe from Water Solution Using Latvian Sphagnum Peat Moss: Thermodynamic Assessment, Kinetic and Isotherm Modeling

A green and environmental–friendly method for the removal of the hazardous bromothymol blue from aqueous solution was considered applying a hydrophilic, biocompatible and biodegradable natural sorbent of Latvian sphagnum peat moss, applying shaking-dispersive solid-phase extraction. First, the influence of shaking speed was evaluated at 300, 600, 900 U. Furthermore, the optimum conditions of dye-adsorption, such as pH, adsorption-equilibrium contact time, adsorbent mass, and adsorbate initial concentration were investigated. In addition, the adsorption equilibrium isotherms, thermodynamics, and kinetics were studied. Thus, the optimum removal of bromothymol blue was concluded at a shaking speed of 600 U. Regarding the dye adsorption at different pH, bromothymol blue showed two removal maxima at acidic (pH 2.5) and almost neutral (pH 7.5) media, reaching dye % removal of 80.8 and 88.2 %, respectively, in 120 min of adsorption equilibrium contact time. Moreover, the dye removal improved reasonably by increasing the concentration and the sphagnum dose. Additionally, the equilibrium isotherm plot correlated comparably to Langmuir's and Freundlich's models. Also, the adsorption kinetic study demonstrated a better correlation to pseudo-secondorder plot than to pseudo-first-order one. Finally, excellent reproducibility in % removal was demonstrated with RSD values of 2.2 and 2.7% at pH of 7.5 and 2.5, respectively.

Evaluation of Soybean Plant Introductions for Traits that can Improve Emergence under Varied Soil Moisture Levels

When drought occurs during the soybean (Glycine max L. Merr.) sowing period, emergence will most likely be affected. We evaluated a diverse panel of 373 plant introductions under controlled environmental conditions for primary root length (PRL) (at 100, 80, 60, 40, and 20% pot water holding capacity (PWHC); pots filled with potting soil that contained Sphagnum peat moss (>50%), bark, and perlite), and time taken for radicle emergence (TRE). The PRL decreased ≥75% at 40% PWHC, compared to 100, 80, and 60% PWHC. No genotypes germinated at 20% PWHC. We identified superior genotypes in terms of PRL and TRE, and found a positive relationship between PRL and emergence that became stronger with decreases in soil moisture levels. This indicates the importance of PRL in improving emergence, which becomes greater with decreases in soil moisture levels or increases in severity of drought. Seed weight was not related to PRL and emergence, indicating that larger seeds will not necessarily have longer PRL and better emergence. As the soybean panel used in this study was previously assessed for traits associated with drought tolerance at the late-vegetative and flowering stages, and the present study assessed it for putative traits related with emergence under various soil moisture conditions, the panel will become an important resource for soybean improvement.

A biotic strategy to sequester carbon in the ornamental containerized bedding plant production: A review

Identifying options of climate change mitigation is of global interest to researchers. Whereas wide range of techniques of reducing greenhouse gas (GHG) emissions and carbon sequestration have been studied in row crops and forest systems, little research has been done on the ornamental horticulture. The ornamental industrial sector has indeed some negative impacts on the global environment, but also presents opportunities to reduce GHG emissions and increase C sequestration. Thus the objective of this study was to synthesize the potential contributions of some substrates used in the horticultural sector to carbon sequestration. The specific focus of the review is on the possible use of compost, vermicompost and biochar as soilless substrate substitutes for containerized ornamental plants production. Around 11 million kilograms of sphagnum peat moss are used annually in the world for horticultural production. Therefore, the potential of using compost, vermicompost and biochar as growing media is assessed on the basis of data from greenhouse studies. Peat-based substrate can be substituted up to 30% to 35% by compost or vermicompost and up to 20% to 25% by biochar. Some examples from field studies are included to conduct the life cycle assessment of using these growth media. An estimate of C storage on the long-term basis in soil indicates up to 3 million tons of CO2 equivalent as the maximum C potential storage per year in the global productive sector if the peat-based growing media are substituted by compost/vermicompost and biochar at the ratios mentioned above. Finally, synergies between compost vermicompost and biochar are discussed when these materials are combined as growing media additives and research gaps in this area of activity have been identified for further research.

Lime Rate Affects Substrate pH and Container-grown Birch Trees

ABSTRACTNursery production of birch (Betula nigra L.) trees commonly occurs in containers using a soilless substrate such as pine bark or peat moss. Birch trees have been reported to suffer from pH-induced micronutrient deficiencies in landscapes; thus, they are recommended to be planted in low-pH soils (<6.5). Little research has addressed the influence of substrate pH on birch trees during container production. Therefore, the objective of this research was to determine if substrate pH influences birch tree growth and development. Birch (Betula nigra ‘NBMTF’) liners were transplanted into 11.4 L plastic nursery containers filled with an 80 pine bark: 20 sphagnum peat moss (v:v) amended with either 0.6 kg.m−3 of elemental sulfur (S) or 0, 1.8, 3.5, or 7.1 kg.m−3 dolomitic lime. Substrate pH ranged from 4.8 to 7.3. There were only a few and minor differences in leaf chlorophyll content and no differences in plant growth. Differences in leachate and plant tissue nutrient concentration occurred for some elements, although these differences were not enough to affect plant growth. Container-grown birch trees can be grown over a wide range of substrate pH (4.8 to 7.3) with little or no effect on their growth.

Assessment of various treatment methods and reagents for cleanup and conditioning of sphagnum peat moss as sorbents in removal of malachite green as a cationic organic dye probe from water

Twelve sphagnum peat moss samples were studied for removal of malachite green, as a cationic dye probe, in assessment of various pretreatment methods using three low-cost reagents, applying different approaches such as flow-through, shaking, stirring, and sonication. These sphagnum sorbents were categorized as non-treated (sorbent 1), water-treated (sorbents 2–4), hydrochloric-acid-treated (sorbents 5–8), and finally sodium-hydroxide-treated (sorbents 9–12). Foremost, the physicochemical features of these sorbents were assessed in terms of acidity, matrix emission, total dissolved salts, cation-exchange capacity, and particle morphology. As a matter of fact, different reagents and treatment methods showed dissimilar enhancement in dye removal tendency. Yet, the water and hydrochloric acid treatments by sonication (sorbents 4 and 8) and more remarkably the sodium hydroxide treatment by shaking (sorbent 10) afforded astonishing dye removal rates. Correlating the dye removal tendencies of these sorbents, with their physical properties and sorbent capacity, indicated a slight fall in their cation-exchange capacity plus a genuine change in the particle shape and substantial reduction in size. Finally, excellent reproducibility was demonstrated for the cation-exchange capacity, % removal, and the adsorption pseudo-second-order rate constant.

Development of a method for protonema proliferation of peat moss (Sphagnum squarrosum) through regeneration analysis.

The moss Sphagnum (peat moss) is ecologically and economically important. There is a paucity of physiological and developmental studies on Sphagnum because of the lack of an axenic culture system for its whole life cycle. A culture system has been established for the Sphagnum gametophore, but not the protonema (juvenile vegetative stage after spore germination). Therefore, the aim of this study was to develop a protonema culture system for Sphagnum. Sphagnum squarrosum gametophore tissue was disrupted and then cultured in liquid Knop medium. The regeneration of protonemata from the gametophore fragments was analyzed in detail by microscopy. We observed a developmental balance between filamentous and thalloid protonemata, and growth competition between the thalloid protonema and the gametophore. On the basis of these findings, we established a relatively stable peat moss protonema proliferation method. Using this method, all the developmental stages of peat moss vegetative growth could be obtained through differentiation or regeneration. The method can provide abundant homogeneous Sphagnum materials at desired stages for physiological and developmental studies, and will be useful for large-scale Sphagnum vegetative proliferation. The regeneration analysis method will be useful for establishing protonema proliferation systems for other mosses.

Insect-based compost and vermicompost production, quality and performance

AbstractIn an attempt to utilize large amounts of Japanese beetles, Popillia japonica (Coleoptera: Scarabaeidae) that were captured using a mass trapping system, compost using Japanese beetle carcasses was prepared with the layer method. Carbon sources included shredded paper, wood chips and leaves, while the sole nitrogen source was frozen Japanese beetles. In addition, Japanese beetle-based vermicompost was prepared in the greenhouse by mixing the Japanese beetle-based compost with sphagnum peat moss and moist shredded paper and exposing this mixture to composting earthworms (Eisenia fetida). Chemical analyses of the Japanese beetle carcasses indicated that 10.8% of their body weight is nitrogen (N). Analyses of the resulting Japanese beetle-based compost and vermicompost indicated that both types of materials are good quality soil amendments. Greenhouse studies were conducted to quantify the effects of varying proportions of Japanese beetle-based vermicompost and compost mixed with a potting medium and varying dosages of synthetic fertilizer 20-0-0, on mean fresh and dry weight of lettuce shoots and leaf area. Japanese beetle-based compost and vermicompost increased lettuce biomass to an extent that was comparable with the addition of synthetic N-based fertilizer. A mixture of 15 and 30% of each compost type with potting media significantly increased plant weight and leaf area compared with potting medium alone. Results indicate that composting and vermicomposting insect carcasses are a simple, effective and affordable method to augment fertilization in support of organic production.

Rosemary growth and nutrient balance: Leachate fertigation with leachates versus conventional fertigation

Abstract The free discharge of drainage water from greenhouse horticultural production to the environment is a current environmental concern due to its capacity to contribute to environmental pollution. This has led to the search of sustainable alternatives for its reuse in the production of other crops. However, before the large-scale use of such horticultural leachates in ornamental plants, the effects of such fertigation treatments on ornamental plants need to be evaluated. Plants of rosemary were grown in pots with a mixture of sphagnum peatmoss and Perlite and subjected to three fertigation treatments: T0 (a standard nutrient solution or control), T1 (raw leachates from Cucumis melo) and T2 (a mixture of raw leachates from C. melo and tap water 1:1 v/v, over a period of 9 weeks. At the end of the experiment, the growth parameters, color of leaves as well as water and nutrient uptake efficiencies and their losses were assessed for each fertigation treatment. The total dry weight and the water use efficiency of rosemary plants decreased under the fertigation with raw and diluted leachates. In addition, rosemary plants were shorter compared to the control but there were no differences in leaf color between the fertigation treatments. The uptake of N, P and K were affected by the applied fertigation treatments in a different manner. The use of horticultural leachates in the production of ornamental plants (as shown here for melon and rosemary) is feasible and presents a viable option to reduce water and nutrient input in plant production.

Survival of Steinernema feltiae in different formulation substrates: Improved longevity in a mixture of gel and vermiculite

Entomopathogenic nematodes (EPNs) have been commercially produced as biopesticides, but nematode products still face significant barriers related to preservation and formulation. This study assessed the performance of seven different formulation substrates and two combinations involving vermiculite and gel, to preserve Steinernema feltiae at three temperatures: 15 °C, 25 °C and 35 °C. The first two experiments assessed the survival and mobility of S. feltiae infective juveniles (IJs) in mushroom compost (Hobin Wood Landscaping Products), peat (sphagnum peat moss), Potting mix (Metro Mix®), polyacrylamide gel, diatomaceous earth, vermiculite, and water (control). A third experiment assessed the survival of IJs in combinations of the two best substrates selected from the prior tests: vermiculite, polyacrylamide gel (1.33%), double polyacrylamide gel (2.66%), vermiculite + gel (1.33%), vermiculite + double gel (2.66%), and water (control). The greatest IJ fitness at 35 °C and 25 °C was observed in peat and vermiculite, respectively, and at 15 °C the gel and water treatments were superior. In general, vermiculite and polyacrylamide gel were the two best substrates considering that they provided the best results at 25 °C and 15 °C. The polyacrylamide gel formulation held higher numbers of nematodes in the substrate compared with the solid substrates. The mixture of vermiculite + double polyacrylamide gel provided the best preservation at 35 °C compared to the substrates tested separately. The combination of vermiculite with polyacrylamide gel preserves S. feltiae IJs with viability higher than 80% for at least 30 days at 35 °C, 233 days at 25 °C, and 241 days at 15 °C.

Ultrafast and Highly Efficient Removal of Malachite Green from Aqueous Solution by Latvia-Originated Sphagnum Peat Moss Sorbent Applying Dispersive Solid-Phase Extraction

The removal of malachite green from aqueous solution by Latvia-originated sphagnum peat moss was investigated applying dispersive solid-phase extraction. A sorbent powder, of particle size < 250 μm, was pretreated by successive refluxing of sphagnum in water, alcohol, and acetone. Foremost, the absorbance of the sphagnum matrix was assessed at the dye absorbance maxima of 254, 550, and 616 nm, applying different solution pH values. Furthermore, the optimum conditions of malachite green adsorption, such as equilibrium time, pH, adsorbent mass, and adsorbate initial concentration were investigated. In addition, the equilibrium isotherms and adsorption kinetics were studied. Fortunately, the absorbance ratio of malachite green to that of sphagnum matrix was the highest at pH 7.0 and 616 nm. Regarding dye extraction, a breakthrough in the adsorption speed was concluded, where a 2-min adsorption equilibrium contact time of 98.1% dye removal and a remarkable 30-s dye uptake of 97.3% were accomplished. Additionally, the equilibrium isotherm plot correlated well with Freundlich’s model (R2 = 0.9223). Also, the adsorption kinetic study demonstrated good correlation to the pseudo-second-order plot (R2 = 0.9999). Finally, excellent reproducibility of eight extraction replicates was demonstrated furnishing an average equilibrium dye removal of 97.8% and RSD of 1.06%.