Current approaches to waste polymer utilization and minimization: a review

Abstract

The mass production of polymer products, in particular plastics, and their widespread use depending on the inherent advantages they have, make these materials ironically a threat to life on Earth. Polymer recycling is being considered as one of the most widely accepted remedies to the threat of growing amounts of plastic waste by both the public and scientists. In practice, recycling is associated with many difficulties, such as problems related to separation, sorting and cleaning operations, lack of fiscal subsidies, instability of selective garbage separation programs, high transport and electricity costs, etc. Still, a large section of society and the authorities agree on the necessity and importance of recycling to protect the environment, and natural habitats and resources for future generations in a balanced manner to conserve raw materials, and to reduce energy consumption, municipal solid waste production and greenhouse gas emission. The recycling effort is almost endless in itself and includes a variety of approaches such as refurbishing, mechanically reshaping, chemically treating, thermally utilizing, etc. Some novel approaches such as application in carbon capture or synthesis of carbon nanostructures from the plastic waste are among the new process technologies of recycling. From traditional and promising polymer waste utilization approaches, this review will highlight sustainable methods to reduce impacts of plastic waste on the environment. © 2018 Society of Chemical Industry

Fe3O4@C particles synthesized with iron‐containing water treatment residuals and its potential for methylene blue removal

“…After shaking, the magnetic adsorbent was drawn out using a simple magnet from the aqueous solution and the concentration of the residual MB in the solution was determined using a visiblespectrophotometer at maximum wavelength of MB, = 665 nm. The MB adsorbed by the adsorbent was calculated using Eqn (1):…”

“…where C 0 (in mg/L) represents the initial MB concentration; C e (in mg/L) is the equilibrium MB concentration in solution after adsorption; V (in liters) is the volume of the aqueous solution and m (in grams) is the weight of Fe 3 O 4 @C particles. Similar to the earlier process, kinetic experiments were carried out at two different initial MB concentrations and an initial pH of 7.0 by measuring the MB adsorption at different time intervals under 308 K. The data of q t , the MB adsorption during time, t, is calculated in a similar way to Eqn (1).…”

“…Research on waste utilization has boomed recently as the existing sources in the Earth are very limited and a great number of matter that is discarded shows very promising potential to be utilized again . Many sorts of wastes are worth being recycled and re‐used, not only for transferring these materials into re‐used sources but reduce the costly waste disposal expenses .…”

“…Research on waste utilization has boomed recently as the existing sources in the Earth are very limited and a great number of matter that is discarded shows very promising potential to be utilized again. [1][2][3] Many sorts of wastes are worth being recycled and re-used, not only for transferring these materials into re-used sources but reduce the costly waste disposal expenses. 4,5 For instance, water treatment plants have been built globally for supplying clean and safe water for humans by removing containments from source water, in which a mass of water treatment sludge has been produced continuously.…”

Residuos urbanos, agrícolas y pecuarios en el contexto de las biorrefinerías

“…Por ejemplo, en el desarrollo de diferentes productos (estibas plásticas, casas prefabricadas, etc. )[37], en el reforzamiento asfaltico, en la producción de monómeros y absorbentes poliméricos, entre otros[38]. La generación de residuos agrícolas a nivel mundial para el año 2016 se proyectó en 368.329.087.469 t aproximadamente[39].En Colombia, la producción de residuos agrícolas estimada a partir de los cultivos más representativos para el año 2017 fue de 218.007.204 t. De esta cantidad, los cultivos que más residuos generan son la caña de azúcar (155.866.414 t), el plátano (26.547.871 t) y el banano (12.674.307 t)[40,41].…”