In this study, a direct contact membrane distillation process was used to achieve rejection of 25 pharmaceutically active compounds (PhACs) in water. The influence of natural organic matter (NOM), a common contaminant in waters that are used for water supply, on PhACs removal was investigated. Humic acid was used as an organic model in order to represent major constituents of NOM. Results indicated that flux decline slightly increased from 0 to 8% as HA feed concentration increased from 0 to 80 mg L⁻¹. Flux decline was mainly associated with membrane fouling which added hydraulic resistance to the transfer of liquid water. Pore wetting was observed when HA concentration increased, which indicated changes in the hydrophobic character of the membrane. MD process showed a rejection of ≥ 99% for the 25 assessed PhACs for all HA concentration evaluated even at high permeate recovery rate (60%), whereas, 24 PhACs presented concentrations below limit detection. The retention of PhACs by MD membrane occurs predominantly by membrane rejection which is mainly governed by volatility and, to a lesser extent, by hydrophobia. The adsorption contribution to PhACs retention was low (<8%) and was significantly associated with positively charged compounds. Although the feed side of the membrane became hydrophilic due to the HA deposit, the PhACs retention by DCMD was not affected, which reinforces the robustness of the process and the ability to produce safe water. Thus, in general, DCMD is less influenced by the feed composition than nanofiltration or reverse osmosis, implicating in higher PhACs rejections.

在这项研究中，直接接触膜蒸馏工艺用于实现水中25种药物活性化合物（PhACs）的排阻。研究了用于供水的水中常见污染物天然有机物（NOM）对PhAC去除的影响。腐植酸被用作有机模型，以代表NOM的主要成分。结果表明，随着HA进料浓度从0增加到80 mg L ^-1，通量下降从0增加到8％。通量下降主要与膜结垢有关，膜结垢增加了液态水传输的水力阻力。当HA浓度增加时，观察到孔润湿，这表明膜的疏水特性发生了变化。MD过程显示，即使在高透过率（60％）的情况下，对于所有评估的HA浓度，对25个评估的PhAC的拒绝率均≥99％，而24个PhAC的浓度低于极限检测值。MD膜对PhAC的保留主要是通过膜排斥而发生的，而膜排斥主要由挥发性控制，在较小程度上由疏水性控制。吸附对PhACs保留的贡献很低（<8％），并且与带正电荷的化合物显着相关。尽管膜的进料侧由于HA沉积而变得亲水，DCMD对PhAC的保留不受影响，这增强了过程的稳健性和生产安全水的能力。因此，通常，与纳滤或反渗透相比，DCMD受进料组成的影响较小，这意味着较高的PhAC截留率。