Sorption of cationic dyes from aqueous solutions by moss Rhytidiadelphus squarrosus: Kinetics and equilibrium studies

With the aim to investigate sorption properties of natural sorbent prepared from moss Rhytidiadelphus squarrosus we elucidated biosorption of cationic dyes Malachite green (BG4), Auramine O (BY2) and Thioflavine T (BY1) from aqueous solutions. The removal of dyes by moss biosorbent was found to be rapid at an initial stage and the equilibrium was reached within 1-2 hours. The pseudo-n-order kinetic model was successfully applied to the kinetic data and the order of adsorption reaction was calculated in the range from 1.7 to 2.6. The value of rate constant kn' ranged from 0.001 to 0.039 [min-1]/[μmol/g]1-n. The equilibrium data were fitted to the adsorption isotherms. The Freundlich isotherm was found to represent the measured sorption data of BG4, BY1 and BY2 well. The maximum sorption capacities of moss biomass from single dye solutions calculated by Langmuir equation were 354 μmol/g for BG4, 310 μmol/g for BY1 and 382 μmol/g for BY2. These results showed that the prepared biomass presents low-cost, natural and easy available sorbent which may be potentially used for removal of dyes from environment and also may be an alternative to more costly materials such as activated carbon.

Rice Straw as a Natural Sorbent in a Filter System as an Approach to Bioremediate Diesel Pollution

Rice straw, an agricultural waste product generated in huge quantities worldwide, is utilized to remediate diesel pollution as it possesses excellent characteristics as a natural sorbent. This study aimed to optimize factors that significantly influence the sorption capacity and the efficiency of oil absorption from diesel-polluted seawater by rice straw (RS). Spectroscopic analysis by attenuated total reflectance infrared (ATR-IR) spectroscopy and surface morphology characterization by variable pressure scanning electron microscopy (VPSEM) and energy-dispersive X-ray microanalysis (EDX) were carried out in order to understand the sorbent capability. Optimization of the factors of temperature pre-treatment of RS (90, 100, 110, 120, 130 or 140 °C), time of heating (10, 20, 30, 40, 50, 60 or 70 min), packing density (0.08, 0.10, 0.12, 0.14 or 0.16 g cm−3) and oil concentration (5, 10, 15, 20 or 25% (v/v)) was carried out using the conventional one-factor-at-a-time (OFAT) approach. To eliminate any non-significant factors, a Plackett–Burman design (PBD) in the response surface methodology (RSM) was used. A central composite design (CCD) was used to identify the presence of significant interactions between factors. The quadratic model produced provided a very good fit to the data (R2 = 0.9652). The optimized conditions generated from the CCD were 120 °C, 10 min, 0.148 g cm−3 and 25% (v/v), and these conditions enhanced oil sorption capacity from 19.6 (OFAT) to 26 mL of diesel oil, a finding verified experimentally. This study provides an improved understanding of the use of a natural sorbent as an approach to remediate diesel pollution.

Coco Peat as Agricultural Waste Sorbent for Sustainable Diesel-Filter System

Oil spill incidents are hazardous and have prolonged damage to the marine environment. Management and spill clean-up procedures are practical and rapid, with several shortcomings. Coco peat (CP) and coco fibre (CF) are refined from coconut waste, and their abundance makes them desirable for diesel spillage treatment. Using a filter-based system, the selectivity of coco peat sorbent was tested using CP, CF and peat-fibre mix (CPM). CP exhibited maximal diesel sorption capacity with minimal seawater uptake, thus being selected for further optimisation analysis. The heat treatment considerably improved the sorption capacity and efficiency of diesel absorbed by CP, as supported by FTIR and VPSEM–EDX analysis. Conventional one-factor-at-a-time (OFAT) examined the performance of diesel sorption by CP under varying parameters, namely temperature, time of heating, packing density and diesel concentration. The significant factors were statistically evaluated using response surface methodology (RSM) via Plackett–Burman design (PB) and central composite design (CCD). Three significant (p < 0.05) factors (time, packing density and diesel concentration) were identified by PB and further analysed for interactions among the parameters. CCD predicted efficiency of diesel absorbed at 59.92% (71.90 mL) (initial diesel concentration of 30% v/v) and the experimental model validated the design with 59.17% (71.00 mL) diesel sorbed at the optimised conditions of 14.1 min of heating (200 °C) with packing density of 0.08 g/cm3 and 30% (v/v) of diesel concentration. The performance of CP in RSM (59.17%) was better than that in OFAT (58.33%). The discoveries imply that natural sorbent materials such as CP in oil spill clean-up operations can be advantageous and environmentally feasible. This study also demonstrated the diesel-filter system as a pilot study for the prospective up-scale application of oil spills.

Current concepts of the role of fiber in the bird

Realization of the genetic potential of poultry productivity in industrial poultry farming is achieved by creating optimal conditions for keeping poultry and providing it with compound feeds, balanced in terms of metabolic energy and a complex of nutrient, mineral and biologically active substances. Fiber has always been and remains among the standardized indicators in mixed feed for poultry, since its excessive amount in a number of feed products (hulled crops, bran, sunflower meal, cake, etc.) is associated with a reduced digestibility of nutrients and energy availability). It is believed that fiber maintains the balance of the intestinal microflora, stimulates the growth of the muscular stomach and motility of the digestive tract, being a natural sorbent, absorbs toxic substances and ensures normal digestion and absorption of nutrients in feed. Despite the fact that the presence of fiber in compound feed for poultry is inevitable, the opinion of experts on its benefits differs.On the one hand, leading breeding companies and scientists consider fiber to be a necessary component for the development of the gizzard in order to stimulate the consumption of compound feed. On the other hand, poultry nutritionists try not to overload diets with fiber, especially if they consist of components that are difficult to hydrolyze, as this reduces the energy value of the diet. In addition, wastes from flour and fat-and-oil industries are often associated with such disadvantages as increased bacterial contamination or mycotoxin contamination. There is another controversial point that different sources of fiber have different effects on the digestive system, which is associated with the presence of anti-nutritional factors in the feed that affect its solubility. The review of publications provides information on the role of insoluble fiber in the body of poultry and its traditional and alternative sources.

Lead sorption from aqueous solutions by kaolinite: laboratory experiments

The lead has adverse effects in contamination the aquatic environment, for this reason, a laboratory simulation was conducted using kaolinite collected from the Ga’ara Formation at western Iraq to be considered as a natural sorbent material that can be addressed Pb2+ from the aqueous environments. The Energy-Dispersive X-ray Spectroscopy and atomic absorption spectroscopy clarifying very fine grains and pure phase with a very little quantity of quartz and has a number of active sites for adsorption. The sorption of kaolinite for the Pb2+ has been carefully tested by several designed laboratory experiments. Five lead solutions of different concentrations (25, 50, 75, 100 and 125 ppm) were tested under different values of pH (1.3-9). The best sorption has been recorded at pH 9, with an equilibrium reaction time 40 m and the solid-liquid ration 1.25 gm:50 ml. The sorption reaction is endothermic with two main mechanisms were identified, the rapid ion exchange which gets at the beginning of the reaction during the first 10 m, and ion exchange, which gets slow later due to form ionic complexes

Regularities of Adsorption of Α-Oxypropionic Acid By Natural Zeolite

Wastewaters from dairy processing factories contaminated with α-oxypropionic acid were monitored. Theoretical analysis of industrial wastewater treatment methods on zeolites of Sokyrnytsia deposit was carried out. The process of sorption of α-oxypropionic (α-oxypropionic) acid by natural zeolite of Sokyrnytsia deposit was considered. It was established that the most economically advantageous and safe is the method of adsorption using a natural sorbent - zeolite, which provides the lowest concentration of contaminants in treated wastewaters from dairies. An assessment of their number, localization features and measures of toxicological impact on the environment was done. The existing theoretical apparatus of description of adsorption processes was analyzed. The sorption properties of natural zeolite (clinoptilolite of Sokyrnytsia deposit) and activated carbon to α-oxypropionic acid were tested. Equilibrium values of adsorption capacity were calculated and corresponding isotherms at a temperature of 20 ° С were constructed. The porosity of the sorbent and its influence on the sorption properties were studied by the methods of physicochemical analysis. Infrared spectroscopic and electron microscopic studies confirmed the presence of the process of sorption by the surface of the internal pores of the zeolite of α-oxypropionic acid molecules. Experimental studies have confirmed the possibility of using natural zeolite for wastewater treatment of dairy factories. It was experimentally confirmed by physicochemical methods of analysis (electron microscopy, IR spectroscopy, microprobe analysis, mercury porometry) and was established that the process takes place both by the mechanism of ion exchange and physical adsorption. The content of carbon radicals in the zeolite matrix after the sorption process was confirmed by X-ray spectral microanalysis. The ability of zeolite to adsorb organic carboxylic acid radicals was confirmed by the results of IR spectroscopic studies. On the IR spectra there are strips of deformation and valence oscillations of the groups of the crystal lattice of the zeolite Si-O, Si-O-SiOH: 452, 990–1210, 1638, 3368 cm−1. The oscillation spectra of free OH groups in the region of 2600 cm−1 were revealed.

Application of Sorbents for Oil Spill Cleanup Focusing on Natural-Based Modified Materials: A Review

Conventional synthetic sorbents for oil spill removal are the most widely applied materials, although they are not the optimal choices from an economic and environmental point of view. The use of inexpensive, abundant, non-toxic, biodegradable, and reusable lignocellulosic materials might be an alternative to conventional sorbents, with obvious positive impact on sustainability and circular economy. The objective of this paper was to review reports on the use of natural-based adsorbing materials for the restoration of water bodies threatened by oil spills. The use of raw and modified natural sorbents as a restoration tool, their sorption capacity, along with the individual results in conditions that have been implemented, were examined in detail. Modification methods for improving the hydrophobicity of natural sorbents were also extensively highlighted. Furthermore, an attempt was made to assess the advantages and limitations of each natural sorbent since one material is unlikely to encompass all potential oil spill scenarios. Finally, an evaluation was conducted in order to outline an integrated approach based on the terms of material–environment–economy.

Use of Natural Sorbent for Stormwater Treatment

Stormwater runoff is an important avenue for pollutant transport from impermeable surfaces to surface waters. Consequently, stormwater pollutions require additional treatment processes to achieve water quality goals. Natural sorbents have been demanded and studied for using in water treatment because of their low cost and safety. In this study the use of Acorus Calamus, row Hemp, and procedure Hemp in stormwater treatment was investigated. Results of study in all sorbents with different concentrations and dosage indicated high efficiency to reduce pH. The use of Acorus Calamus for Turbidity, Phosphorus, conductivity and colour resulted increasing amount in different Dosage. In another experiments, using row Hemp, procedure Hemp and Linseed as natural sorbents indicated high efficiency to reduce turbidity of stormwater. Also it is obtained that procedure Hemp has high efficiency to reduce conductivity of stormwater.