Department of Civil and Environmental Engineering, Rowan University, 201 Mullica Hill Road, Glassboro, NJ, 08028, USA.
Department of Civil and Environmental Engineering, Rowan University, 201 Mullica Hill Road, Glassboro, NJ, 08028, USA.
Chemosphere. 2023 Apr;321:138165. doi: 10.1016/j.chemosphere.2023.138165. Epub 2023 Feb 15.
Hydrothermal liquefaction (HTL) is an attractive technology for the conversion of wet waste into biofuel and co-HTL has been touted to increase the quality of products. However, the recovery of energy from wastewater byproduct called aqueous co-product (ACP) is limited due to the presence of toxic inhibitory substances. Adsorption has been countenanced to remove these toxic compounds but there has not been a distinct comprehensive adsorption isotherm study to explain the interaction between the adsorbate molecules and the adsorbent sites. This study investigated the sorption mechanism of oxidizable reducing pollutants measured as chemical oxygen demand (COD); heavy metals (boron and copper); and phenols from ACP samples obtained from co-HTL of brewery trub (BT), and primary sludge (PS) onto granular and powdered activated carbon (GAC and PAC). Conventional isotherm models such as Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich were used for data analysis. Results indicated that the adsorptive capacity (qe) of PAC was greater than GAC in COD adsorption (BT-1947 > 234; BTPS-617 > 245; PS-289 > 207), boron adsorption (BTPS-70 > 7; PS-53 > 49), copper adsorption (BT-5 > 1; BTPS-3 > 2; PS-1.3 > 1.1) and phenol adsorption (BT-1340 > 356; BTPS-1587 > 253; PS-460 > 245) in mg/g, μg/g, μg/g, and μg/g respectively. Comparing the adsorption of pollutants onto PAC and GAC, this study observed that PAC followed the Temkin, and Dubinin-Radushkevich models in the adsorption of the four pollutants while GAC followed the Freundlich and Langmuir models in the adsorption of phenol and copper, and Temkin, and Dubinin-Radushkevich in the adsorption of COD and boron. This study proved that combining feedstock in HTL (co-HTL) does not only change the quality of the ACP but also changes the dynamics of the adsorption isotherms. The Free Energy Change (ΔG) result showed a spontaneous reaction in the adsorption of copper and phenol. This study presents an adsorption equilibrium information for the interpretation of adsorption isotherms for the overall improvement of adsorption mechanism pathways and the effective design of adsorption systems for the treatment of ACP.
水热液化（HTL）是一种将湿废物转化为生物燃料的有吸引力的技术，共 HTL 已被吹捧为提高产品质量。然而，由于存在有毒抑制物质，从废水副产物称为水相共产物（ACP）中回收能量是有限的。吸附已被认为是去除这些有毒化合物的一种方法，但目前还没有明确的综合吸附等温线研究来解释吸附质分子与吸附剂位之间的相互作用。本研究调查了可氧化还原污染物的吸附机制，这些污染物被测量为化学需氧量（COD）；重金属（硼和铜）；以及从酿酒渣（BT）和初沉污泥（PS）的共 HTL 中获得的 ACP 样品中的酚类物质，分别在颗粒状和粉末状活性炭（GAC 和 PAC）上的吸附。使用了常规等温线模型，如朗缪尔、弗伦德利希、坦金和杜比宁-拉乌捷希科夫模型进行数据分析。结果表明，PAC 的吸附容量（qe）在 COD 吸附（BT-1947>234；BTPS-617>245；PS-289>207）、硼吸附（BTPS-70>7；PS-53>49）、铜吸附（BT-5>1；BTPS-3>2；PS-1.3>1.1）和酚类吸附（BT-1340>356；BTPS-1587>253；PS-460>245）方面大于 GAC，mg/g、μg/g、μg/g 和μg/g 分别为毫克/克、微克/克、微克/克和微克/克。比较 PAC 和 GAC 对污染物的吸附，本研究观察到 PAC 对四种污染物的吸附遵循 Temkin 和杜比宁-拉乌捷希科夫模型，而 GAC 对酚类和铜的吸附遵循 Freundlich 和朗缪尔模型，对 COD 和硼的吸附遵循 Temkin 和杜比宁-拉乌捷希科夫模型。本研究证明，在 HTL（共 HTL）中结合原料不仅会改变 ACP 的质量，还会改变吸附等温线的动力学。自由能变化（ΔG）的结果表明，铜和酚类的吸附是自发反应。本研究为吸附等温线的解释提供了吸附平衡信息，以解释整体改善吸附机制途径和有效设计用于处理 ACP 的吸附系统。
