Carlos Barrera Díaz

Effects on Mechanical Properties of Recycled PET in Cement-Based Composites

Concretes consisting of portland cement (OPC), silica sand, gravel, water, and recycled PET particles were developed. Specimens without PET particles were prepared for comparison. Curing times, PET particle sizes, and aggregate concentrations were varied. The compressive strength, compressive strain at yield point, and Young modulus were determined. Morphological and chemical compositions of recycled PET particles were seen in a scanning electron microscopy. Results show that smaller PET particle sizes in lower concentrations generate improvements on compressive strength and strain, and Young’s modulus decreases when the size of PET particles used was increased.

Soft drink wastewater treatment by electrocoagulation–electrooxidation processes

ABSTRACT The aim of this work was to implement a coupled system, a monopolar Electrocoagulation (EC)–Electrooxidation (EO) processes, for the treatment of soft drink wastewater. For the EC test, Cu–Cu, anode–cathode were used at current densities of 17, 51 and 68 mA cm−2. Only 37.67% of chemical oxygen demand (COD) and 27% of total organic carbon (TOC) were removed at 20 min with an optimum pH of 8, this low efficiency can be associated with the high concentration of inorganic ions which inhibit the oxidation of organic matter due to their complexation with copper ions. Later EO treatment was performed with boron-doped diamond-Cu electrodes and a current density of 30 Am−2. The coupled EC–EO system was efficient to reduce organic pollutants from initial values of 1875 mg L−1 TOC and 4300 mg L−1 COD, the removal efficiencies were 75% and 85%, respectively. Electric energy consumption to degrade a kilogram of a pollutant in the soft drink wastewater using EC was 3.19 kWh kg−1 TOC and 6.66 kWh kg−1 COD. It was concluded that the coupled system EC–EO was effective for the soft drink wastewater treatment, reducing operating costs and residence time, and allowing its reuse in indirect contact with humans, thus contributing to the sustainable reuse as an effluent of industrial wastewater.ABSTRACTThe aim of this work was to implement a coupled system, a monopolar Electrocoagulation (EC)–Electrooxidation (EO) processes, for the treatment of soft drink wastewater. For the EC test, Cu–Cu, anode–cathode were used at current densities of 17, 51 and 68 mA cm−2. Only 37.67% of chemical oxygen demand (COD) and 27% of total organic carbon (TOC) were removed at 20 min with an optimum pH of 8, this low efficiency can be associated with the high concentration of inorganic ions which inhibit the oxidation of organic matter due to their complexation with copper ions. Later EO treatment was performed with boron-doped diamond-Cu electrodes and a current density of 30 Am−2. The coupled EC–EO system was efficient to reduce organic pollutants from initial values of 1875 mg L−1 TOC and 4300 mg L−1 COD, the removal efficiencies were 75% and 85%, respectively. Electric energy consumption to degrade a kilogram of a pollutant in the soft drink wastewater using EC was 3.19 kWh kg−1 TOC and 6.66 kWh kg−1 COD. It wa...

An Integrated Electrochemical-Phytoremediation Process for the Treatment of Industrial Wastewater

In this chapter we explain the nature of the industrial wastewater. In most of the cases, the pollutants are very toxic and inhibit the biological activity of the microorganisms used in the biological treatment. Therefore, combined methods are required to successfully improve the water quality. In this approach we integrate the use of electrocoagulation that eliminates the colloidal matter present in wastewater and phytoremediation which is performed using Myriophyllum aquaticum as a polishing step. When these methods are used, the wastewater quality is improved. In order to verify the Myriophyllum aquaticum health status, we determinate the chlorophyll content, growth of the plant, and enzymatic activity of superoxide dismutase (SOD), catalase, and peroxidation lipid levels. With the purpose of checking the health status of Myriophyllum aquaticum, we determined some biomarkers as chlorophyll content, the plant growth, and activity of antioxidant enzymes: superoxide dismutase (SOD), catalase, and lipid peroxidation levels. The macrophytes may be tolerant at residual contaminants from wastewater treated with electrocoagulation to a dilution of 19 % starting of a COD of 974. The coupled electrocoagulation (using aluminum electrodes) phytoremediation system was more efficient as compared with the electrochemical treatment.