The preparation of organophosphorus ligand-modified SBA-15 for effective adsorption of Congo red and Reactive red 2

Abstract

P,P-bis (2-oxooxazolidin-3-yl)-N-(3-(triethoxysilyl)propyl)phosphinic amide (APTES-BOP)-modified SBA-15 (SBA-15-BOP) was prepared by a post-synthesis grafting method for the removal of anionic azo dyes from aqueous solutions.

A 2-Fold Interpenetrated Nitrogen-Rich Metal–Organic Framework: Dye Adsorption and CO2 Capture and Conversion

“…CR (pK a = 5.5) has a red color (see Figure 2a) with a pH of 6.6 in our adsorption studies; thus, CR exists in the anionic form. 36,37 The test ζ potential of 1a was 9.76 mV. Therefore, there is an electrostatic attraction in the absorbing process of CR − .…”

Selective Adsorption and Removal of Congo Red Based on Ethylenediamine Functionalized Mesoporous Silica

“…After modifying with high loading of amino (Haribandhu Chaudhuri et., 2016), the adsorption capacity of CR was greatly increased (230.95 mg/g) compared with pure SBA‐15 [3] . Mesoporous silica shows excellent adsorption performance after reasonable organic functionalization; however, it exhibits poor specificity toward targeted dye, such as CR [6,11,26–28] . To date, a desirable absorbent with high efficiency and selective separation of dyes such as CR is still lacking.…”

“…prepared multifunctionalized nano‐silica KCC‐1 through post‐functionalization to remove acid orange II (676.7 mg/g) and acid fuchsin (621.3 mg/g) [25] . However, these adsorbents have low selectivity and capacity, which hinder the efficient removal, recovery, and reuse of specific dyes [2,6,11,26–29] …”

“…It is widely used in the paper, food, and textile industries, but it is highly toxic and generally non-degradable. [1,8,27,30] Hence, the selective adsorption, separation, and reuse of CR are important. Recently, modified porous materials were used for adsorption studies.…”

“…[25] However, these adsorbents have low selectivity and capacity, which hinder the efficient removal, recovery, and reuse of specific dyes. [2,6,11,[26][27][28][29] Congo red (CR) is a typical diazo dye containing two unsaturated chromogenic groups (azo group) and four color assisting groups (amino group and sodium sulfonate group). It is widely used in the paper, food, and textile industries, but it is highly toxic and generally non-degradable.…”