Preparation of organic-inorganic hybrid porous materials and adsorption characteristics for (-)-epigallocatechin gallate and caffeine from the extract of discarded tea

Abstract

A series of novel organic-inorganic hybrid porous materials were synthesized using the method of suspension polymerization. As content of oleic acid-coated TiO 2 introduced increased, the surface area, pore volume, and average pore diameter increased, and meantime macropores appeared. The adsorption efficiencies of the porous materials for (2)-epigallocatechin gallate (EGCG) and caffeine (CAF) were enhanced, due to synergistic effect of surface area, pore volume, average pore diameter, and several driving forces such as charge induced force, p-p stacking, and hydrogen bond. Adsorption kinetic analysis indicated that pseudo-second-order kinetics can reasonably depict the adsorption process, and intraparticle diffusion became more obvious after a contact time of 30 min. Adsorption isotherm analysis indicated Freundlich isotherm could be used to describe the adsorption process. Charge induced force, p-p stacking, hydrogen bond, and sieving effect of pores were the main driving forces for the adsorption of EGCG and CAF by the organic-inorganic hybrid porous materials. This study will open possibility of expanding number and types of porous materials and provide assistance in tailoring corresponding physical-chemical properties, according to specific analytes. POLYM. ENG. SCI., 55:2414-2422, 2015

Preparation of hypercrosslinked polymers with cashew nut shell liquid for removal of volatile organic compounds

“…[41,42] So benzene and o-xylene can form stronger interactions with CNSL-HCP4 than that of acetone, and o-xylene's higher molecular weight and low saturated vapor pressure contributed to its higher adsorption amount than that of benzene. [43]…”

“…In addition, the weakened interactions between polymers and adsorbate with increasing temperature lead to the decrease of the adsorption efficiency. [43] So the rise of the temperature corresponds to the decline in adsorption ability. [45] While the adsorption capacity of o-xylene on CNSL-HCP4 decreases with the temperature rises, near-complete desorption (>99%) occurs at 120 C for polymers.…”

A Review of Caffeine Adsorption Studies onto Various Types of Adsorbents

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Design and synthesis of a new porous organic polymer equipped with N‐propyl sulfamic acid functionalities: As an efficient heterogeneous catalyst for the synthesis of 1,8‐dioxo‐octahydroxanthene derivatives

“…In recent years, porous organic polymers (POP)s , as a rapidly expanding class of materials, have been attracting a great deal of attention by combining porous properties with organic functionalization features. In this way, mesoporous organic polymers (mesoPOP)s , have been known incredibly owing to their structural motifs which provide appropriate positions for immobilizing homogeneous catalysts and therefore making them heterogenized.…”