Functional PAN-based monoliths with hierarchical structure for heavy metal removal

Abstract

Efficient removal of lead from aqueous media remains a serious task for public health and environment. Here polyacrylonitrile (PAN) monolith is fabricated by means of thermally induced phase separation (TIPS), a novel method that can be used for the preparation of hierarchically structured monolith without any templates assisted. Three hierarchically structured adsorbents (D-PAN, H-PAN, A-PAN) based on PAN monolith were successfully prepared by reacting with diethylenetriamine (DETA), sodium hydroxide, and hydroxylamine hydrochloride, respectively. The Pb (II) adsorption ability of all modified samples was determined by a series of batch tests. Experimental data illustrated that all samples showed excellent Pb (II) adsorption ability and the maximum adsorption capacity of D-PAN, H-PAN, and A-PAN was 144 mg g-1 , 206 mg g-1 and 242 mg g-1 , respectively. The feasible preparation of

Facile Modification of a Polythiophene/TiO2 Composite Using Surfactants in an Aqueous Medium for an Enhanced Pb(II) Adsorption and Mechanism Investigation

“…The regeneration study was conducted for further mechanism investigation. HNO 3 and EDTA-Na had been applied as elution agents in many laboratorial and large-scale investigations, which had been recognized as effective ways for the adsorbent recycle. − Based on the fact that adsorption capacities of composites were strongly pH dependent, 1 mol/L of HNO 3 was employed as a desorption agent, and 0.1 mol/L of NaOH was used to activate adsorbents. Results were depicted in Figure a–b.…”

Amidoxime-Functionalized Hollow Carbon Spheres for Efficient Removal of Uranium from Wastewater

“…Uranium caused widespread environmental contamination because of mining and milling, and uranium-containing radioactive waste disposal. − Due to the toxicity and bioaccumulation of uranium, it is of great importance to decrease its bioavailability and remove it from wasteswater . Several methods, such as precipitation, coprecipitation, ion-exchange, and sorption , were employed to remove uranium from wastewater. Among these methods, the sorption was generally considered as an economical and effective approach due to its simple design, convenience, cost-efficiency, and extensive adaptability .…”

Uniform macroporous amidoximated polyacrylonitrile monoliths for gallium recovery from Bayer liquor

“…27 However, there have been very few reports on the adsorption and recovery of substances in aqueous solution so far. 28 Thermally induced phase separation (TIPS) is a novel method for preparing porous materials by using the principle that polymers and diluents are compatible at high temperatures, while phase separation occurs at low temperatures. In this case, the growth of a polymer-poor phase will result in a cellular structure after diluent extraction.…”

“…Also, carbon‐based monoliths are reported to adsorb methyl orange with a maximum adsorption capacity of 88.5 mg/g although the equilibrium time is as long as 5800 min 27 . However, there have been very few reports on the adsorption and recovery of substances in aqueous solution so far 28 . Thermally induced phase separation (TIPS) is a novel method for preparing porous materials by using the principle that polymers and diluents are compatible at high temperatures, while phase separation occurs at low temperatures.…”