Boron adsorption mechanism on polyvinyl alcohol

Abstract

Recently, an increase in the use of boron compounds has led to an increase in boron emissions, and concern has grown regarding its detrimental effects on the human body. An adsorbent that adsorbs boron selectively has been developed as a countermeasure. Although certain commercially available boron selective adsorbents can be used to remove boron from aqueous solutions by utilizing the strong affinity between boron and hydroxyl groups, the adsorption capacity appears to be insufficient. So, we adopted polyvinyl alcohol (PVA), which contains many hydroxyl groups, as a model adsorbent. We investigated the boron adsorption characteristics of PVA, and then studied the relationship between the number of adsorption sites and actual adsorption amounts. We assessed the adsorption result by using adsorption site availability (ASA) as an indicator of the ratio of effectively functioning hydroxyl groups from the many hydroxyl groups in PVA. ASA was expressed as a percentage of the experimental equilibrium adsorbed amount in relation to the theoretical equilibrium adsorbed amount. We also compared the adsorption isotherms and ASA obtained with PVA, commercially available N-methylglucamine-type resin (CRB03 and CRB05) and the adsorbent we synthesized from polyallylamine (PAA) and glucose (PAA-Glu). Although PVA has many hydroxyl groups in a molecule, ASA analysis revealed that only 6% of the hydroxyl groups in PVA was used for boron adsorption. On the other hand, CRBs and PAA-Glu exhibited higher ASA values (about 15% and 35% respectively) and adsorption amounts, sug-

Mechanism of boron uptake by hydrocalumite calcined at different temperatures

“…Although the maximum boron concentration in drinking water in World Health Organization is 2.4 mg/L, tougher standards at 1.0 mg/L were established in many them, hydroxyl-containing boron-selective adsorbents are considered to be one of the best promising materials for boron removal [8,14,15], such as the boron specific resin (such as IRA743, CRB 05), which is the most representative adsorbent for borate. However, the higher production cost of resin is a great shortage [16]. Therefore, numerous low cost adsorbents and waste products have been investigated in recent years [17].…”

Rapid Synthesis of LDHs Using Dolomite as a Magnesium Source and Application to Borate Removal

“…The maximum sorption capacity of LDH-D-900 was 1.34 mmol/g, which is close to the 1.29 mmol/g and 1.20 mmol/g for LDHs prepared from chemical reagents by Ferrier et al 12) and Jiang et al 13) The borate sorption capacity of LDH-D-900 was also similar to that reported previously for CRB 05, a kind of borate-specific resin. 14) Because LDH-D-900 showed better sorption performance than LDH-D-675, the solid residues of LDH-D-900 were collected after the sorption experiment and characterized by 11 B MAS NMR to explore the sorption mechanism ( Fig. 5).…”

Boron contamination in drinking - irrigation water and boron removal methods

“…Bor pek çok endüstri için oldukça faydalı bir bileşendir. Bor bileşikleri ilaç üretiminden metal endüstrisine kadar geniş bir aralıkta kullanılmaktadır [25]. Cam endüstrisi dünyadaki toplam bor bileşiklerinin üretiminin yarıdan fazlasını kullanan en önemli endüstridir.…”