Selective Recovery of Palladium (II) from Metallurgical Wastewater Using Thiadiazole-Based Chloromethyl Polystyrene-Modified Adsorbent

Selective adsorption of palladium from metallurgical wastewater containing Pt (IV), Rh (III), Ca²⁺, Cu²⁺, Fe³⁺, Ni²⁺, Pb²⁺, V³⁺, and Ti⁴⁺ has tremendous economic and environmental benefits. In this paper, a novel thiadiazole-based chloromethyl polystyrene-modified adsorbent, viz. 2, 5-bis-polystyrene-1,3,4-thiadiazole (PS-DMTD), was synthesized using chloromethyl polystyrene as the backbone. The experimental results show that PS-DMTD can selectively separate Pd (II) from metallurgical wastewater in a one-step adsorption process. The calculated saturation adsorption capacity of PS-DMTD for Pd (II) was 176.3 mg/g at 25 °C. The separation factors of β_{Pd (II)/M}ⁿ⁺ (Mⁿ⁺: Pt (IV), Rh (III), Ca²⁺, Cu²⁺, Fe³⁺, Ni²⁺, Pb²⁺, V³⁺, and Ti⁴⁺) were all higher than 1 × 10⁴. FT-IR, XPS, and single-crystal X-ray diffraction showed that the adsorption of Pd (II) to PS-DMTD was primarily through a coordination mechanism. Density functional theory (DFT) calculations revealed that the other base metal ions could not coordinate with the PS-DMTD. Pt (IV) could not be adsorbed to PS-DMTD due to its strong chlorophilicity. Furthermore, Rh (III) existed as a polyhydrate, which inhibited Rh (III) diffusion toward the positively charged absorption sites on the PS-DMTD. These results highlight that PS-DMTD has broad application prospects in the recovery of Pd (II) from metallurgical wastewater.     

八氯甲基笼型倍半硅氧烷的合成及表征

以氯甲基三氯硅烷为原料,甲醇、氯仿和石油醚为混合溶剂,在浓盐酸和无水三氯化铁为催化剂的条件下水解缩合制备了八氯甲基笼型倍半硅氧烷(CM-POSS)。利用FT-IR、GPC、1 H-NMR、29Si-NMR和XRD等技术对产物的结构进行了表征,并通过TGA研究了其热稳定性。结果表明产物为八氯甲基笼型倍半硅氧烷,且热稳定性良好。     

微波辅助合成可溶性聚合物——线型氯甲基化聚苯乙烯

在微波辅助下制备了线性氯甲基化聚苯乙烯 ,研究了苯乙烯和 4-氯甲基苯乙烯浓度与配比、反应时间、微波功率等对聚合反应的影响 ,发现 St/ CMS接近于 1 ,30 %微波功率 ,反应 1 5 min可得到可溶性的线性氯甲基化聚苯乙烯 ,转化率达 49%,氯含量达 4.2 mmol/ g。     

3-卤-2-卤甲基-1-丙烯合成方法改进

以季戊四醇为原料经卤代、氧化、热分解三步主要反应合成了3-卤-2-卤甲基-1-丙烯.卤代反应中采用不同的卤代剂合成了三卤代新戊醇,在文献基础上加入以二氯甲烷为萃取剂的萃取过程可使三卤(氯)新戊醇产率达72%-98%;再通过氧化反应得到三卤(氯或溴)新戊酸,同样加入萃取过程可使酸的产率达到63%-80%,最后热分解脱卤化氢和二氧化碳制备3-卤-2-卤甲基-1-丙烯时(卤素为氯和溴),在文献基础上加入吡啶作催化剂可使热分解温度降至200 ℃(原分解温度为260 ℃),总产率可达45%-72%.在制备3-碘-2-碘甲基-1-丙烯时避光搅拌,可降低产物分解,产率为60%.所有的化合物经过了IR和1HNMR的确认.     

Thermoreversible hydrogels. XIX. Synthesis and swelling behavior and drug release behavior for the N‐isopropylacrylamide/poly(ethylene glycol) methylether acrylate copolymeric hydrogels

A series of thermosensitive copolymeric hydrogels were prepared from various molar ratios of N‐isopropylacrylamide (NIPAAm) and poly(ethylene glycol) methylether acrylate (PEGMEA_n), which was synthesized from acryloyl chloride and poly(ethylene glycol) mono methylether with three oxyethylene chain lengths. Investigation of the effect of the chain length of oxyethylene in PEGMEA_n, and the amount of the PEGMEA_n in the NIPAAm/PEGMEA_n copolymeric gels, on swelling behavior in deionized water was the main purpose of this study. Results showed that the swelling ratio for the present copolymeric gels increased with increasing chain length of oxyethylene in PEGMEA_n and also increased with increase in the amount of PEGMEA_n in the copolymeric gels. However, the gel strength and effective crosslinking density of these gels decreased with increase in swelling ratio. Some kinetic parameters were also evaluated in this study. Finally, the drug release and drug delivery behavior for these gels were also assessed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1683–1691, 2003     

1,4-双(氯甲基)-2-甲氧基-5-辛氧基苯及聚合物的合成

由对甲氧基苯酚（ＭＯＰｈ）合成出一种可溶性电致发光共轭聚合物聚（２－甲氧基－５－辛氧基）亚苯基亚乙烯（ＰＭＯＯＯＰＶ）大致过程为：由ＭＯＰｈ与１－溴辛烷合成１－甲氧基－４－辛氧基苯（ＭＯＯＯＢ）继而合成了１,４－双（氯甲基）－２－甲氧基－５－辛氧基苯（ＢＣＭＭＯＯＯＢ）碱性聚合得可溶性ＰＭＯＯＯＰＶ。并做了ＢＣＭＭＯＯＯＢ与其它单体的共聚,对中间体及聚合物用＾１ＨＮＭＲ进行了表征。     

O-邻氟苯甲基羟胺盐酸盐的合成

以丙酮肟和邻氟氯苄为原料合成了O-2-氟苯甲基丙酮肟醚,再用盐酸水解得到了O-2-氟苯甲基羟胺盐酸盐。文章系统研究了反应温度、不同溶剂、溶剂含水量等各种实验因素对O-2-氟苯甲基丙酮肟醚的影响,研究了盐酸浓度、水解温度等因素对O-2-氟苯甲基丙酮肟醚水解工艺的影响。两步收率最高分别为92.3%和87.3%。并用核磁等对产品及中间体进行了表征。     

氯甲基笼型倍半硅氧烷改性双酚A环氧树脂性能

引言双酚A环氧树脂是目前应用最广、用量最大的环氧树脂,具有良好的化学稳定性、电气绝缘性被广泛应用于涂料和电子电器等领域;然而,双酚A环氧树脂存在耐热性较差和固化后脆性大等缺点,因此如何提高环氧树脂的耐热性及力学性能等是目前改性研究的热点之一[1-5]。而笼型多面体倍半硅氧烷(POSS)是一类具有(RSiO1.5)n通式的纳米材料,因其特殊的分子组成结构使得POSS具     

Synthesis,characterization, and fluorescence of end‐functionalized polystyrene initiated by 4‐chloromethyl benzoic acid and ethyl 4‐chloromethyl benzenecarboxylate via ATRP

End‐functionalized polystyrene (PSt) was synthesized via atom‐transfer radical polymerization (ATRP) by using 4‐chloromethyl benzoic acid (CMBA) and the ethyl‐protected carboxylic acid, ethyl 4‐chloromethybenzenecarboxylate (ECBC), as initiators respectively. The structure of PSt proved the living‐radical polymerization. Results exhibit both ATRP initiators afforded well‐controlled polymerization with high initiator efficiencies. However, the study also shows the controllability of ATRP can be obviously influenced by using different initiator in different catalyst system. Furthermore, the terminal group of the PSt1, benzoic acid, can coordinate with Europium(III) ion to obtain the polymeric Eu(III) complex, which shows both emissions of polymer and Eu(III) ion. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007