Human exposure to per‐ and polyfluoroalkyl substances (PFAS) in drinking water is of growing concern as a result of increasing reports of occurrence and potential regulation. Adsorption of PFAS by granular activated carbon (GAC) or ion exchange (IX) resin is a suitable treatment technique. However, few studies compare PFAS removal in continuous flow GAC or IX adsorption systems using real drinking water sources. In this study, rapid small‐scale column tests (RSSCTs) were used to investigate the effects of PFAS type and chain length on adsorption by GAC and IX resin for six groundwaters used as drinking water supplies. Seven PFAS substances with chain lengths of C4–C9 were detected in the groundwaters with the sum of their concentrations (ΣPFAS) ranging from 156 to 7,044 ng/L. Adsorption capacities (qΣPFAS) were calculated to compare the removal capacity among different sorbents and qΣPFAS values ranged from 10.3 to 228 ng PFAS/mg sorbent after about 100,000 bed volumes treated. Coal‐based GACs had higher adsorption capacity compared with coconutshell‐based GAC, which was likely due to higher mesopore and macropore volumes. IX resins performed better than GAC in removing PFAS, but they were not effective in treating short‐chain perfluorocarboxylic acids (PFCAs). Perfluorosulfonic acids (PFSAs) broke through later than PFCAs with the same chain length. Within PFSA or PFCA classes, shorter‐chain PFAS species always broke through before longer‐chain PFAS. Statistical analysis demonstrated that PFAS with higher hydrophobicity and molecular weight are more amenable to GAC adsorption. Empirical models were developed and predicted PFAS breakthrough. By quantifying PFAS selectivity and removal efficiency, this work provides benchmark data for commercially available treatment technologies and guidance toward specific PFAS classes for which new treatment technologies may be most beneficial.

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In recent aura, the potentiality of hydrogen as an alternative fuel is a proven fact. Due to the higher calorific value and eco-friendly nature, it has already gained considerable popularity in laboratory scale though the commercialization of the same faced quite a challenge due to lower extraction values. The present work incorporates production of commercial grade biohydrogen fuel from distillery spent wash activated with different dosage of raw xylose. The yield was also investigated under two retention periods such as 8 hr and 12 hr, but in both the scenario the dose of 20 g/l found to be most effective. A significant difference was also observed both in terms of hydrogen yield and chemical oxygen demand (COD) reduction against the retention time with 12 hr Hydraulic retention time (HRT) found to be associated with more satisfactory values in both the cases which are approx. 196 ml (39.2 ml/d) and 65% COD reduction respectively. Future this paper also comprises to identify the indigenous species responsible for the hydrogen production by Scanning Electron Microscope (SEM) analysis. It reveals o cocciand rod-shaped organism in accumulated sludge.