Removal of Emerging Contaminants by Fenton and UV-Driven Advanced Oxidation Processes

This paper is closed access.The removal efficiencies of four different parabens (methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP)) using Fenton reagent, UV irradiation, UV/H2O2, and UV/ H2O2/Fe2+ were evaluated to assess the level of paraben degradation achieved using different advanced oxidation processes (AOPs). UV irradiation by itself provided paraben conversions between 27 and 38 % after a reaction time of 180 min. The UV/ H2O2 system increased the paraben conversion to values between 62 and 92 %, and the Fenton process was revealed as inefficient in paraben degradation within the experimental conditions used. Photo- Fenton presented similar removal rates to the UV/ H2O2 process. Among the four parabens studied, butylparaben was the most easily removed, and it was possible to attain degradations higher than 90 %. In the UV/H2O2 and photo-Fenton processes, the overall kinetic constant could be split into two main components: direct oxidation by UV radiation (photolysis) and oxidation by free radicals (mainly HO•) generated from the photodecomposition of H2O2. This work reveals that UV-driven oxidation processes can be widely used to remove parabens from contaminated aqueous solution

Testing a conditional cash transfer program in the U.S.: the effects of the family rewards program in New York City

Family Rewards represents the first test of a Conditional Cash Transfer (CCT) program in the U.S., offering families incentives for children's education, family preventive health care and parents' work and training. Using a randomized controlled trial, we find that the program led to substantial reductions in poverty and hardship during the 3 years in which the rewards were offered. The program also led to some effects in each of the three areas of education, health and work, although the effects were fairly modest or limited to certain subgroup