Boron Selective Resin Research Articles

Desorption and Reusable Properties of a New Boron-Selective Hybrid Gel Adsorbent

A hybrid gel adsorbent bearing boron-selective functional groups was prepared by the reaction of bis(trimethoxysilylpropyl)amine (TSPA) and a gel precursor in water. The gel precursor was synthesized from (3-glycidoxypropyl)trimethoxysilane (GPTMS) andN-methylglucamine (MG). The boron adsorption behavior of the gel and a commercial boron-selective resin D564 was investigated. The gel adsorbent has a suitable mechanical strength and an adsorption capacity of 2.00 mmol g-1, which is higher than that of the resin D564 (1.64 mmol g­-1). Boron can be desorbed from both the gel and the resin D564 with a 0.25 mol L-1HCl solution. The good reusability of both the gel and the resin D564 was confirmed by fourteen consecutive adsorption-desorption-regeneration cycles.

Non-equilibrium sorption modeling for boron removal from geothermal water using sorption–microfiltration hybrid method

In this study, the boron removal performance of a hybrid system composed of ground ion exchange resin particles coupled with a microfiltration separation unit was investigated. A non-equilibrium sorption modeling approach was introduced so as to understand the contributions of mass transfer resistances on the effluent stream concentration profiles, as well as on the resin loading scheme of this sorption–microfiltration hybrid system. This modeling approach allowed us to suggest new system operations and/or scale-up processes of sorption–microfiltration hybrid systems. In this study, the highly porous crosslinked boron selective chelating resins Diaion CRB02 and Dowex XUS 43594.00 containing N-methyl-glucamine group were used. Geothermal water that has high levels of boron was fed into the stirred cell element of the microfiltration system. Kinetic behaviour of boron selective resins for boron removal from geothermal water by the microfiltration system was evaluated to investigate the effects of resin particle size, resin concentration, and permeate flow rate.

Design and fabrication of an innovative and environmental friendly adsorbent for boron removal

Boron can pose adverse effects on human beings and plants species. It exists in various water environments and is difficult to be removed by conventional technologies. In this study, an efficient and environmental friendly sorbent was fabricated by the functionalization of a natural biopolymer, chitosan, with N-methylglucamine through atom transfer radical polymerization. The SEM and BET studies revealed that the sorbent had a rougher surface and a more porous structure than the chitosan. At the optimum neutral pH, the maximum sorption capacity was as high as 3.25 mmol/g, much higher than the commercial boron selective resins (e.g., Amberlite IRA-743) and many other synthesized sorbents. Almost 90% of boron sorption occurred within 8 h and the equilibrium was established in 12 h, which was well described by an intraparticle surface diffusion model. The presence of sodium chloride and sodium nitrate had no effect on the boron removal. The boron concentration in seawater could be reduced to less than 0.5 mg/L from 4.8 mg/L when a sorbent dosage of 1.2 g/L was used. It was therefore concluded that the sorption technology from this study could be promising for boron removal from aqueous solutions.

Adsorption-membrane filtration process in boron removal from first stage seawater RO permeate

The paper deals with evaluation of adsorption-membrane filtration (AMF) hybrid process in removal of trace amounts of boron from the first stage RO permeate. Finely ground boron selective resin, Dowex XUS 43594.00, was used as sorbent while polypropylene capillaries with pore dimension of 0.4 μm as the submerged membranes. The process combined delivery of feed and fresh resin suspension with subsequent removal of the loaded sorbent. The effects of such process variables were evaluated: diameter of resin bead, concentration of suspension, rate of suspension replacement and time of the system run. It was found that to reduce boron concentration from 2 mg/L to the WHO recommended level, 1 g/L of resin should be used. During 48 h of process, neither membranes fouling by the sorbent particles nor sedimentation of resin was observed. When resin was subjected to regeneration particle diameter was not changed after 20 alternating immersions in acidic and basic solutions.

Removal of boron from seawater by adsorption–membrane hybrid process: implementation and challenges

The advanced separation process for boron removal has been put forward by combining boron sorption on a fine powdered boron selective resin (BSR) with a complex separation on microfiltration membranes. The proposed membrane-based hybrid process integrates in one step sorption efficiency of the selective resin with membrane separation. It is shown that use of sorbent in the form of very fine particles improves the separation efficiency such that sorbent shows higher uptakes and enhances the rate of the separation process. The process efficiency was evaluated for ground Dowex XUS 43594 resin. In this study, the effect of feed flow rate, BSR suspension concentration and rate of suspension replacement were investigated. A simple model was presented. The obtained data shows a great potential for adsorption membrane filtration hybrid system in removal of trace amounts of boron.

Boron removal from aqueous solution by reverse osmosis

Boron is biologically an essential nutrient for many plants but high boron concentrations in irrigation water cause toxic effects whereas low abundances require boron addition to maximize crop yields. High boron levels in drinking water can be also toxic to humans. There is no easy method for the removal of boron from waters and wastewaters. One or more method may be applied according to boron cocentration in medium. For boron removal, main processes that have been studied are (1) precipitation–coagulation; (2) adsorption on oxides, active carbon, cellulose or clay minerals; (3) ion exchange with basic exchanger; (4) use of boron selective resin; (5) solvent extraction; (6) membrane filtration (electrodialysis, reverse osmosis etc.) In this study boron removal by reverse osmosis was examined. First part of this article reviews current studies about boron removal by reverse osmosis. In the second part of study boron removal by reverse osmosis from aqueous solution (5 mg B/L) was investigated and the rejection ratio of boron was obtained as 69%.

Boron recovery from borax sludge using solid–liquid extraction followed by sorption with a boron selective resin in column

AbstractThe recovery of boron from borax sludge was studied. Initially, the solid–liquid extraction was applied to borax sludge in a batch reactor. Subsequently, the extraction solution was treated with the Amberlite IRA‐743—boron specific resin for the separation of boron from the calcium and magnesium components in the extraction solution. In the batch studies, the effect of pH on the boron recovery was studied by adjusting the pH of extraction solution using HCl and NaOH solution. Optimum boron recovery of 44% was obtained at pH 8. The column studies were carried out using different inlet boron concentrations and flow rates at pH 8 and 25°C. Thomas and the Yoon–Nelson Models were found suitable to describe the dynamic behavior of the column and to determine the column kinetic parameters for process design. Almost all the boron, which was sorbed by the resin was eluted using a 0.5 M H2SO4 solution. It was seen that the concentrations of other species in the elution solution were insignificant so that it could not to be detected. In this process, boron was successfully separated from the calcium and magnesium species. It was determined that approximately 70% of the boron in the extraction solution could be recovered at an inlet boron concentration of 250 mg/L, a flow rate of 2.5 mL/min, a pH value of 8 and a temperature of 25°C. © 2007 American Institute of Chemical Engineers Environ Prog, 2007

Donnan dialysis of borate anions through anion exchange membranes: A new method for regeneration of boron selective resins

The studies on sorbent regeneration by Donnan dialysis have been presented. Two kinds of anion exchange membranes were evaluated: microheterogenous, based on interpenetrating polymer network and homogenous prepared from modified homopolymer. The studies revealed that sodium chloride is the salt that forced borate transport more effectively than sodium sulfate does. Both membranes showed similar efficiency in borate transport. It was shown that the particle diffusion within resin particles was the limiting process parameter for regeneration of boron selective resins.

Kinetic behaviour of boron selective resins for boron removal using seeded microfiltration system

In this study, boron selective ion exchange resins (Dowex-XUS 43594.00 and Purolite S 108) and model boron solutions at different ionic strengths were used in order to perform continuous kinetic studies in a seeded microfiltration stirred cell provided by Micropore Technologies (UK). Mass transfer modelling based on a well stirred system, including maximum capacity ( Q m, mg/g) and Langmuir constant ( b, L/mg) values obtained from a Langmuir isotherm, coupled with film diffusion around the resin particle and internal diffusion within the particle, was used to predict concentration change of boron against time. Finally, experimental results were compared with the modelling data for different ionic strength mediums to determine the diffusivity of boron inside the resin and mass transfer coefficients.

Boron removal from drinking water with a boron selective resin: is the treatment really selective?

Drinking water and even mineral water may contain boron until a few ppm and WHO has recommended a limit of 0.3 mg boron l −1. The treatment by the resin Amberlite IRA743 seems to be the most convenient. Water deboronation with this resin has been revisited through laboratory column experiments, especially for low boron concentrations. Given that the resin bears weakly basic anion exchange groups, the specificity of the treatment is not obvious. For mineral waters, it is important that the ionic composition remains constant. It is shown here that anion exchange reactions occur but may be neglected when the water has sufficient ionic strength and/or being gasified with carbon dioxide. Thus, the treatment with Amberlite IRA743 is convenient, but it requires to be authorized in France and the minimization of regeneration solutions has still to be improved.

Removal of Boron from Geothermal Power Plant Wastewater in Kizildere, Turkey

Geothermal energy is an alternative renewable energy resource that has proven itself technically and economically feasible as a nonpollulanl electric power source. The Denizli-Kizildere geothermal energy region is the first major geothermal energy resource project in Turkey, with an estimated potential of 200 MW. The use of the geothermal potential of the region depends on removal of its high boron content, since waste brine is discharged into the nearby Bilyuk Menderes River. This article represents a study for removing boron from Kizildere / Turkey geothermal wastewater using the boron selective resin Amberlite FRA-743. The effect of regenerant type and regeneration conditions has been investigated to find the optimal operational conditions for minimizing the regenerant consumption.

A preliminary study on boron removal from Kizildere/Turkey geothermal waste water

A study is made of boron removal from Kizildere/Turkey geothermal waste water using the boron selective resin Amberlite IRA 743. The resin in salt form has no boron removal capacity if the solution is unable to neutralize the released acid during the exhaustion period. In the case of Kizildere waste water, with a pH value of 8.9 and high HCO 3 − content, single stage regeneration is feasible and the exhausted resin can be regenerated economically. According to a preliminary estimate, the electricity production cost would rise by 1 ¢/kWh.

Ion-exchange separation and spectrophotometric determination of boron in geological materials

Various dissolution techniques were investigated for total rocks and minerals and the best approach found was alkaline fusion. Boron in silicates was rendered chemically reactive by fusion with potassium carbonate, the fusion cake was extracted with water and borate was isolated by Amberlite XE-243 boron-selective resin. The Amberlite XE-243 resin was utilized to separate microgram amounts of boron from natural waters (fresh to hypersaline) and salt cores. Borate was eluted with 2 M hydrochloric acid and determined by spectrophotometry of the carminic acid complex at 620 nm in either 94% sulphuric acid or sulphuric/acetic acid (20:80) medium, or preferably, as the azomethine-H ion-association complex at pH 5.2 (415 nm), depending on the sensitivity required. Good precision and accuracy were obtained on several international standard rocks with an average relative standard deviation of 1.37%.

Removal of boric acid and related compounds from solutions of carbohydrates with a boron-selective resin (IRA-743)

A boron-selective resin (IRA-743) was used to remove boric acid from synthetic solutions of carbohydrates. A commercially available polystyrene-divinylbenzene resin, which contains (covalently attached) 1-deoxy-1-methylamino- d-glucitol functional groups, absorbed > 11 mg of boric acid per mL of resin. Optimum conditions are described for use of this resin in a model system and in two practical applications: the quantitative removal of boric acid from a preparative-scale ( > 100 g) ketose-synthesis mixture and in the removal of boric acid from a solution of borohydride-reduced sugars (alditols) prior to acetylation and g.l.c. analysis.

Results of questionnaire: Automation in clinical immunology

Novel boron selective chelating resins were synthesized using monodisperse porous poly(VBC-co-DVB) beads by further functionalization with N-methyl-d-glucamine (NMDG) groups. The performance of the resins for boron removal from geothermal water and its reverse osmosis (RO) permeate has been studied using a batch sorption method. It was possible to remove about 93% of boron from geothermal water containing 11.0 mg B/L with 4 g/L of monodisperse functionalized polymer beads. The respective value for RO permeate of geothermal water with 4.8–5.4 mg B/L of concentration was 97% with the same amount of chelating resin. The sorption rate of boron was quite rapid. A sorption equilibrium was reached in 20 min for geothermal water and in 10 min for RO permeate. The kinetic data obtained were evaluated using classical kinetic models and diffusion/reaction models. It was concluded that monodisperse chelating resins obeyed pseudo-second order kinetic model. Also, the rate controlling step of boron sorption was mostly particle diffusion along with chemical reaction.

A new boron-selective resin derived from guar gum

A boron-selective resin has been prepared by cross-linking of a natural plant hydrocolloid (the polysaccharide guaran from guar seeds). Concentration and separation of boron can be achieved on this resin through completing of boron with the cis-hydroxyl groups in the polymer. The method has been applied to the determination of boron.