3.1 Materials and membrane module.
Thiourea was provided by Shandong Jingbo Yifeng Co., Ltd, and the purity was around 98%). Ultrapure water was produced by a laboratorial water purification system (Liaoning Rightleder Environmental Engineering Co., China, LTLD-P50, the conductivity lower than 0.05 μs cm−1). PTFE hollow fiber membrane was produced in Dongda Water Industry Group Co., Ltd. and the PES hollow fiber membrane was produced in the authors’ laboratory.