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A scalable, and cost-effective method was employed to prepare self-supported CuSn bimetallic catalyst on carbon paper. The obtained CuSn catalyst demonstrates high faradaic efficiency of CO around or above 90% at a broad potential range from -0.7 to -1.8 V vs. reversible hydrogen electrode, greatly surpassing Cu or Sn counterparts.

Old corrugated containers with low recyclability were used as raw materials to synthesize a series of aerogels with varying cellulose concentrations in NaOH/urea solution via a freeze-drying process. The resulting aerogels had a rich porous structure with specific surface areas in the range of 132.72-245.19 m 2 .g -1 and mesopore volumes in the range of 0.73-1.53 cm 3 .g -1 , and were tested for CO 2 sorption at ambient temperature and pressure, displaying excellent CO 2 adsorption capacities in the range of 1.96-11.78 mmol.g -1 . Furthermore, the CO 2 /N 2 selectivity of aerogels decreased with decreasing specific surface area, which was mainly caused by the decrease in CO 2 capture. In addition, the CO 2 sorption capacity of the sample with 2% cellulose content, CA-2, exceeded the values reported so far for many other sorbents with higher specific surface areas, and showed reasonable cyclic stability for CO 2 capture. Therefore, this adsorbent represents an attractive prospect for CO 2 uptake at room temperature., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This study aimed to maximise the amount of CO 2 storage by indirect carbonation using paper sludge ash (PSA), which is an alkaline industrial waste. The properties of the following three types of solvents were considered: acids (acetic acid and hydrochloric acid), ammonium salts (ammonium chloride and ammonium acetate) and others (sodium citrate and water). When carbon dioxide was injected into calcium leachates prepared from PSA using acids, carbonation did not occur, and using ammonium salts as solvent, the carbonation efficiency was low. However, after pH swing of the leachates using sodium hydroxide and ammonia solution for acid and ammonium salt solvents, up to 324 kg CO 2 /(ton PSA) and 175 kg CO 2 /(ton PSA) were stored, respectively. When carbon dioxide was injected into calcium leachates prepared from PSA using sodium citrate or water, solid was initially generated which later dissolved. In order to solve this problem, CO 2 injection was stopped just before the pH of the solution reached 10.5 for sodium citrate and 8.3 for water, resulting in the storage of 136 kg CO 2 /(ton PSA) and 29 kg CO 2 /(ton PSA), respectively. Solids obtained through carbonation were pure calcium carbonate.

Paper, a cheap and ubiquitous material, has great potential to be used as low-cost, portable and biodegradable platform for chemical and biological sensing application. In this paper, we are exploring a low-cost, flexible and reliable method to effectively pattern paper for capturing optical dyes and for flow-based delivery of target samples for colorimetric chemical sensing. In this paper, we target the detection of ammonia (NH3) and carbon dioxide (CO2), two of the important environmental and health biomarkers. By functionalizing the paper platform with diverse cross-reactive dyes sensitive to NH3 and CO2, their selective sensing within a certain pH range, as well as their detection at different concentrations can be achieved. The images of paper based device were captured by a flatbed scanner and processed in MATLAB(®) using a RGB model and PCA for quantitative analysis. Paper based devices with readout using ubiquitous consumer electronic devices (e.g. smartphones, flatbed scanner) are considered promising approaches for disease screening in developing countries with limited resources., (Copyright © 2014 Elsevier B.V. All rights reserved.)

There is concern that the carbon prices generated through climate policies are too low to create the incentives necessary to stimulate technological development. This paper empirically analyzes how the Swedish carbon dioxide (CO2) tax and the European Union emission trading system (EU ETS) have affected productivity development in the Swedish pulp and paper industry 1998-2008. A Luenberger total factor productivity (TFP) indicator is computed using data envelopment analysis. The results show that climate policy had a modest impact on technological development in the pulp and paper industry, and if significant it was negative. The price of fossil fuels, on the contrary, seems to have created important incentives for technological development. Hence, the results suggest that the carbon prices faced by the industry through EU ETS and the CO2 tax have been too low. Even though the data for this study is specific for Sweden, the models and results are applicable internationally. When designing policy to mitigate CO2 emissions, it is vital that the policy creates a carbon price that is high enough - otherwise the pressure on technological development will not be sufficiently strong., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The present work introduces the study of the CO2 capture process by zeolites synthesized from paper sludge and scrap glass. Zeolites ZSM-5, analcime and wairakite were produced by means of two types of Structure Directing Agents (SDA): tetrapropilamonium (TPA) and ethanol. On the one hand, zeolite ZSM-5 was synthesized using TPA; on the other hand, analcime and wairakite were produced with ethanol. The temperature programmed desorption (TPD) technique was performed for determining the CO2 sorption capacity of these zeolites at two sorption temperatures: 50 and 100 °C. CO2 sorption capacity of zeolite ZSM-5 synthesized at 50 °C was 0.683 mmol/g representing 38.2% of the value measured for a zeolite ZSM-5 commercial. Zeolite analcime showed a higher CO2 sorption capacity (1.698 mmol/g) at 50 °C and its regeneration temperature was relatively low. Zeolites synthesized in this study can be used in the purification of biogas and this will produce energy without increasing the atmospheric CO2 concentrations., (© The Author(s) 2014.)

The carbon footprint is one of the main factors for measuring CO emissions2, this atmospheric gas represents a worldwide environmental problem. Currently, universities are making inroads into the solution through the quantification and mitigation of CO2. Academic activities and the delivery of physical documents generate high amounts of paper consumption and consequently levels of CO2, which establishes a problem. The objective is to estimate the carbon footprint of the Universidad Técnica Estatal de Quevedo (UTEQ) located in Ecuador. The methodology employed consisted of a quantification of the number of files registered in the academic system per year. The files were multiplied by an average number of sheets obtained through a survey applied to teachers. The carbon footprint was determined by multiplying the CO emission factor2 by annual paper consumption. The emissions obtained are 3.21 ton CO2 eq to 3.00 ton CO2 eq for the year 2020-2021 and 2021-2022, respectively. The virtual education implemented at UTEQ contributed to the fulfillment of climate change objectives, due to the non-emitted CO2 emissions determined in this study, an issue that is related to the achievement of a green university. [ABSTRACT FROM AUTHOR]

• Supercritical CO 2 displaces water from alum, wastewater, and paper sludge. • Multistage dewatering increases the degree of dewatering. • The expanding CO 2 blows out the water during decompression. Supercritical CO 2 (sCO 2) displaces water from wastewater, alum, and papermill sludge. The sCO 2 appears to enter the sludge matrix through viscous fingering through the entrained water. Because the water removed far exceeds the solubility of water in sCO 2 , it must be displaced by the sCO 2 rather than dissolved out. Adding a small amount of soap to the sludge converts some of the bound water into free water, which can then be displaced by sCO 2. Application of the sCO 2 in multiple stages greatly enhances dewatering as compared to a single stage process. Approximately 70, 70 and 85% of the initial water can be removed from alum, wastewater and paper sludges, respectively, through a five-stage process. Staged application of sCO 2 doubles the efficiency of water removal over a single-stage process of the same duration. It is proposed that when the sCO 2 entrained in the sludge is decompressed between stages some of the water is explosively displaced by the expanding CO 2. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Cellulose-based solutions can improve environmental performance of food packaging. • Food products require specific barrier functions from cellulose-based packaging. • Eco-design enables quantifying environmental performance and identifying trade-offs. • Fulfilling the barrier requirements for food product packaging is crucial. This short communication describes the climate change impacts of using cellulose, and more precisely cellulosic fiber-based materials, in food packaging, representing current and emerging industrial state of the art technology, without specific reference to current scientific advances. First, the different types of cellulosic fiber-based packaging materials, which can be used to replace fossil-based packaging materials, are presented for flexible and rigid applications. The focus is on technological solutions with packaging properties that enable the protection of commonly sold food products. The manufacturing processes associated with these cellulosic fiber-based materials is described and the environmental impact assessment of 4 selected case studies presented: stand-up pouches, flexible flow wraps, frozen or chilled food trays, and molded pulp lids. A simplified eco-design Life Cycle Assessment (LCA) was then performed to compare each solution with its fossil-based counterpart. Differences and similarities between the various cellulosic solutions have been identified. Furthermore, the assessment confirms that cellulosic fiber-based materials have reduced environmental impacts as compared to fossil-based counterparts, if a similar packaging weight is obtained. Indeed, all impacts of plastics are between 3 and 5 kg CO 2 eq/kg, while all impacts of cellulosic fiber-based materials are below 1.5 kg CO 2 eq/kg. [ABSTRACT FROM AUTHOR]