<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yandi* Hu</style></author><author><style face="normal" font="default" size="100%">Jiang, Xulin</style></author><author><style face="normal" font="default" size="100%">Zhang, Suona</style></author><author><style face="normal" font="default" size="100%">Cai, Dawei</style></author><author><style face="normal" font="default" size="100%">Zhou, Zehao</style></author><author><style face="normal" font="default" size="100%">Liu, Chuan</style></author><author><style face="normal" font="default" size="100%">Zuo, Xiaobing</style></author><author><style face="normal" font="default" size="100%">Lee, Sang Soo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Coprecipitation of Fe/Cr Hydroxides at Organic–Water Interfaces: Functional Group Richness and (De)protonation Control Amounts and Compositions of Coprecipitates</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental Science &amp;amp; Technology</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2024</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://doi.org/10.1021/acs.est.4c01245</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">8501-8509</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">ron/chromium hydroxide coprecipitation controls the fate and transport of toxic chromium (Cr) in many natural and engineered systems. Organic coatings on soil and engineered surfaces are ubiquitous; however, mechanistic controls of these organic coatings over Fe/Cr hydroxide coprecipitation are poorly understood. Here, Fe/Cr hydroxide coprecipitation was conducted on model organic coatings of humic acid (HA), sodium alginate (SA), and bovine serum albumin (BSA). The organics bonded with SiO2&amp;nbsp;through ligand exchange with carboxyl (–COOH), and the adsorbed amounts and p&lt;em&gt;K&lt;/em&gt;a&amp;nbsp;values of –COOH controlled surface charges of coatings. The adsorbed organic films also had different complexation capacities with Fe/Cr ions and Fe/Cr hydroxide particles, resulting in significant differences in both the amount (on HA &amp;gt; SA(–COOH) ≫ BSA(–NH2)) and composition (Cr/Fe molar ratio: on BSA(–NH2) ≫ HA &amp;gt; SA(–COOH)) of heterogeneous precipitates. Negatively charged –COOH attracted more Fe ions and oligomers of hydrolyzed Fe/Cr species and subsequently promoted heterogeneous precipitation of Fe/Cr hydroxide nanoparticles. Organic coatings containing –NH2&amp;nbsp;were positively charged at acidic pH because of the high p&lt;em&gt;K&lt;/em&gt;a&amp;nbsp;value of the functional group, limiting cation adsorption and formation of coprecipitates. Meanwhile, the higher local pH near the –NH2&amp;nbsp;coatings promoted the formation of Cr(OH)3. This study advances fundamental understanding of heterogeneous Fe/Cr hydroxide coprecipitation on organics, which is essential for successful Cr remediation and removal in both natural and engineered settings, as well as the synthesis of Cr-doped iron (oxy)hydroxides for material applications.</style></abstract><issue><style face="normal" font="default" size="100%">19</style></issue></record></records></xml>