The National University of Tumbes provided important financial support (Proyecto de Investigacion Docente - Resolucion No 1217-2013/UNT-R). The Academy of Sciences of the Czech Republic and Consejo Nacional de Ciencia, Tecnologia e Innovacion Tecnologica (CONCYTEC) in Peru (joint project reg. No. 002/PE/2012) are also gratefully recognized for their support. The Academy of Finland and the Finnish Funding Agency for Innovation (Tekes) are acknowledged for research funding to the AdMatU project from the Development funds and to the HYMEPRO project, respectively. Thanks to Dr. Gladys Ocharan, Alex Diamond, and Hana Snajdaufova (from ICPF) for technical support and Dr. Tomas Strasak (from ICPF) for help with DFT calculations.

The Academy of Sciences of the Czech Republic and Consejo Nacional de Ciencia, Tecnologia e Innovación Tecno-lógica (CONCYTEC) in Peru (joint project reg. No. 002/PE/ 2012) are gratefully recognized for their support.

Composite material (AC-ZnO) was prepared by growing ZnO nanoparticles during the production of biomass based-activated carbon (AC) via the incorporation of zinc acetate in the process. Comprehensive analyses confirmed the presence of ZnO nanoparticles over the AC surface and described the particular nature of the composite adsorbent. Methylene blue (MB) equilibrium data fitted the Dubinin-Radushkevich model. The MB adsorption capacity was higher for the bare activated carbons (197.9–188.7 mg/g) than the activated carbons with ZnO nanoparticles (137.6–149.7 mg/g). The adsorption of the MB on the adsorbents is physical because the mean adsorption energy (E) is between 1.76 and 2.00 kJ/mol. Experiments that combine adsorption and photocatalysis were carried out with different loads of adsorbents and with and without UV-light exposure. Photocatalytic activity was identified mostly at the...

The research of new materials and methods for water treatment is necessary. Two sets of materials were prepared. The one set is composed from CuO/ZnO oxides with variable content of CuO and the second set consists of its biochar impregnated counterparts. The structure and phase composition was determined using X-ray diffraction method and morphology of the materials was studied using scanning electron microscopy. The photodegradation activity and adsorption properties were tested on model pollutant - Methylene blue (MB) dye solution. The experimental kinetic of the data was analyzed using pseudo-first-order and pseudo-second-order kinetic models and the equilibrium data was evaluated using Langmuir, Freundlich and Dubinin-Radushkievic models. It was found that optimal material for photodegradation of MB is 1% CuO/ZnO oxide and for the adsorption of MB is the best material raw corn cob bi...

The project CIMO North-South-South‘‘PROENV2’’, theAdMAtU–project (AKVA Program) financed by the Academy ofFinland, and HYMEPRO financed by the Finnish FundingAgency for Innovation (Tekes) are acknowledged for the financial support. The National University of Tumbes (ProyectoCanon – Resoluci ?on N80722-2014/UNT-R) and the PeruvianNational Council for Science and Technology (CONCYTEC)(Proyecto. No. 002/PE/2012) are gratefully recognized for theirsupport. The authors also want to thank their home universities for their support.

ZnCl2-activated carbon was prepared using coffee husk for phosphate adsorption in aqueous solutions. Textural, morphological and structural analyses were carried out to characterize the produced materials. XRD detected the presence of ZnO in the activated carbon structure, and the measured nitrogen isotherm showed a micro-macroporous structure with 989 m2/g of specific surface area for this material. Phosphate equilibrium and kinetic experiments were conducted. Equilibrium data fit best to the Dubinin-Radushkevich model (r2≥0.96), with maximum adsorption capacities of 59.38 – 63.87 mg P/g in the pH range between 5 and 9. Intraparticle diffusion was the rate-limiting mechanism of the adsorption.

An activated carbon (adsorbent) was prepared from a forestry residual biomass (Capparis scabrida sawdust) by chemical activation with ZnCl2. The adsorbent was tested in kinetic experiments to remove three anionic dyes widely used in the food industry: tartrazine (TR), brilliant scarlet 4R (BS4R) and brilliant blue (BB). The adsorbent was able to remove the dyes in different intensities, and the revealed order of their adsorption ability was BS4R>TR>BB. Most of the kinetic data fit best to the pseudo-second order model; however, high accordance with other models indicates that there is more than one phenomenon to explain the adsorption process. Analyzing the data that fit well to the pseudo-second order model and considering that the equilibrium was reached, the equilibrium adsorption capacity (qe) for TR was 55.3 mg/g (when the AC load was 1 g/l and the TR initial concentration was 50 mg...

Arsenic (As) exposure from surface and groundwater in Peru is being recognised as a potential threat but there are limited studies on As in the food-chain and none on As in Peruvian rice. In this study, we have determined the As content in rice cultivated in the Tumbes river basin located in the northern province of Peru, an area known for extensive rice cultivation. We collected rice and soil samples from agricultural fields, soil was collected using grid sampling technique while rice was collected from the heaps of harvested crop placed across the fields. The average total As concentration in rice was 167.94 ± 71 μg kg−1 (n = 29; range 68.39–345.31 μg kg−1). While the rice As levels were not highly elevated, the As content of few samples (n = 7) greater than 200 μg kg−1 could contribute negatively to human health upon chronic exposure. Average concentration of As in soil wa...

The utilization of unconventional agricultural wastes to obtain new porous carbonaceous materials, at mild pyrolysis temperatures and without complex procedures, for either water treatment and energy storage applications is important from the economic and environmental perspective. In this study, biochars and hydrochars were prepared from banana rachis, cocoa pod husks, and rice husks at 600 °C-2 h, under nitrogen flux. The prepared materials were characterized to better understand how their morphological, textural, physical-chemical and/or structural properties correlate with their methylene blue (MB) adsorption capacities. The material with the best properties (mainly SBET > 800 m2/g) and MB adsorption capacity was a novel biochar prepared from banana rachis (BW-BC). This novel material was selected for additional kinetics and equilibrium adsorption tests for lead (Pb) along with i...