scholarly journals Perbandingan Penggunaan Natrium Perkarbonat, Hidrogen Peroksida, Hipoklorit, dan Xilanase terhadap Sifat Optik Deinked Pulp

2019 ◽  
Vol 9 (02) ◽  
pp. 97
Author(s):  
Muhammad Ridho ◽  
Edwin K Sijabat

Penggunaan bahan baku dari jenis kertas SWL (sorted white ledger) yang berasal dari proses mekanikal dan jenis kertas bekas yang mengandung banyak tinta memiliki dampak negatif karena menyebabkan sifat optik dari deinked pulp yang dihasilkan tidak optimal. Penyebab dari masalah tersebut adalah tingginya kandungan logam dan lignin pada SWL dan kertas bekas. Untuk mengatasi masalah tersebut, pada penlitian ini dilakukan penambahkan DTPA (Diethylene Triamine Pentaacetic Acid) sebagai penghilang kandungan logam dan bahan pemutih untuk menghilangkan lignin. Bahan pemutih yang digunakan adalah natrium perkarbonat, hidrogen peroksida, hipoklorit, dan xilanase. Dilakukan variasi dosis (1%; 1,5%; dan 2%) dan suhu pemutih (50°C, 70°C, dan 90°C) untuk menentukan titik optimal. Hasil penelitian menunjukkan bahwa bahan pemutih yang digunakan mampu meningkatkan derajat cerah dan derajat putih dari deinked pulp. Nilai sifat optik yang paling optimal didapat pada proses pemutihan menggunakan 2% natrium perkarbonat pada suhu 70°C, dengan nilai derajat cerah sebesar 85,30% ISO dan derajat putih sebesar 112,27% ISO. The Comparison of Sodium Percarbonate, Hydrogen Peroxide, Hypochlorite, and Xylanaseon Optical Properties of Deinked PulpAbstract The use of raw materials from SWL (sorted white ledger) paper originating from mechanical processes as well as used paper types that contain a lot of ink has a negative impact because it causes no optimal value for the optical properties of deinked pulp. The cause of these problems is the high content of metals and lignin. To overcome this problem, it is necessary to add DTPA (Diethylene Triamine Pentaacetic Acid) as a remover for metals and bleaching agents to remove lignin. The bleaching agents used in this study were sodium percarbonate, hydrogen peroxide, hypochlorite, and xylanase. Variation of bleach dose (1%, 1,5%, and 2%) and temperature (50°C, 70°C, and 90°C) is performed to determine the optimal point. The results showed that the whitening material used was able to increase the bright and white degrees of deinked pulp. The most optimal optical properties values obtained in the whitening process using 2% sodium percarbonate at 70°C, with a bright degree value of 85.30% ISO and a degree of white of 112.27% ISO. Keywords: SWL, waste paper, sodium percarbonate, hydrogen peroxide, hypochlorite, xylanase.

Author(s):  
Saleem M. ◽  
Yaqoob N. ◽  
Rehman I. Ur-

<div><p><em>Elephant dung is an excellent source of cellulosic fibers that is a basic requirement for paper making. In this study, bleaching was carried out by using eco-friendly bleaching agents such as sodium percarbonate, oxone and hydrogen peroxide. Soda-anthraquinone (soda-AQ) semi-chemical and chemical elephant dung pulps were bleached at varying doses of bleaching agents, bleaching aids and reaction time. Presence of residual lignin after pulping stage was imparting brown color to the pulp and hence was removed by subsequent bleaching stages. Soda-AQ chemical pulps was treated with different multistage bleaching sequences. The results of this study showed that sodium percarbonate and oxone could not achieve targeted brightness for elephant dung pulp samples. Whereas, using three stage hydrogen peroxide bleaching sequence [AP<sub>5</sub>P<sub>3</sub>P<sub>2</sub>] helped to achieve the targeted brightness ~ 60.0 % G.E without much sacrificing the other optical and physical properties of the pulp. Eco-friendly bleaching helped to increase the beauty of the final product. Being rich in fiber, elephant dung pulp has a potential to be blended with other raw materials to make hybrid exotic papers of high market value.<strong></strong></em></p></div>


Syntax Idea ◽  
2021 ◽  
Vol 3 (11) ◽  
pp. 2386
Author(s):  
Hammami Fajar Kurniawan

The existence of the textile industry, especially in batik production in the region, will certainly provide benefits to the area, because it can absorb labor from the area. However, where there are advantages, there will also be disadvantages, as is the case in this textile factory where the liquid waste produced has a negative impact on the environment. This liquid waste comes from the washing and coloring process which contains dyes, heavy metals, and high salt concentrations. This study examines batik waste from a textile factory using the electrocoagulation method with aluminum electrodes. Research on batik wastewater treatment has been carried out. The results of this study prove that the electrode distance and stirring speed variables affect the COD reduction efficiency and TSS reduction in batik waste. In general, the higher the stirring speed and the closer the electrode spacing, the higher the TSS and COD reduction efficiency. There is an optimal point for stirring speed, where the highest reduction in TSS and COD efficiency is obtained at a stirring speed of 200 rpm. From the variables studied, the optimal value for both variables was obtained, namely at the electrode distance of 1.6 and at a stirring speed of 200 rpm, with the result that the efficiency value obtained was a decrease in COD of 89.39% and a decrease in TSS of 90.45 %.


2021 ◽  
pp. 0734242X2110085
Author(s):  
Jabulani I Gumede ◽  
Buyiswa G Hlangothi ◽  
Chris D Woolard ◽  
Shanganyane P Hlangothi

There is a growing need to recover raw materials from waste due to increasing environmental concerns and the widely adopted transition to circular economy. For waste tyres, it is necessary to continuously develop methods and processes that can devulcanize rubber vulcanizates into rubber products with qualities and properties that can closely match those of the virgin rubber. Currently, the most common, due to its efficiency and perceived eco-friendliness in recovering raw rubber from waste rubbers, such as tyres, is devulcanization in supercritical carbon dioxide (scCO2) using commercial and typical devulcanizing agents. The scCO2 has been generally accepted as an attractive alternative to the traditional liquid-based devulcanization media because of the resultant devulcanized rubber has relatively better quality than other processes. For instance, when scCO2 is employed to recover rubber from waste tyres (e.g. truck tyres) and the recovered rubber is blended with virgin natural rubber (NR) in various compositions, the curing and mechanical properties of the blends closely match those of virgin NR. The atmospheric toxicity and cost of the commonly used devulcanization materials like chemical agents, oils and solvents have enabled a shift towards utilization of greener (mainly organic) and readily available devulcanization chemical components. This literature review paper discusses the approaches, which have less negative impact on the environment, in chemical devulcanization of rubber vulcanizates. A special focus has been on thermo-chemical devulcanization of waste tyres in scCO2 using common organic devulcanizing agents.


2021 ◽  
Vol 11 (14) ◽  
pp. 6445
Author(s):  
David Ibarra ◽  
Raquel Martín-Sampedro ◽  
Bernd Wicklein ◽  
Úrsula Fillat ◽  
María E. Eugenio

Motivated by the negative impact of fossil fuel consumption on the environment, the need arises to produce materials and energy from renewable sources. Cellulose, the main biopolymer on Earth, plays a key role in this context, serving as a platform for the development of biofuels, chemicals and novel materials. Among the latter, micro- and nanocellulose have been receiving increasing attention in the last few years. Their many attractive properties, i.e., thermal stability, high mechanical resistance, barrier properties, lightweight, optical transparency and ease of chemical modification, allow their use in a wide range of applications, such as paper or polymer reinforcement, packaging, construction, membranes, bioplastics, bioengineering, optics and electronics. In view of the increasing demand for traditional wood pulp (e.g., obtained from eucalypt, birch, pine, spruce) for micro/nanocellulose production, dedicated crops and agricultural residues can be interesting as raw materials for this purpose. This work aims at achieving microfibrillated cellulose production from fast-growing poplar and olive tree pruning using physical pretreatment (PFI refining) before the microfibrillation stage. Both raw materials yielded microfibrillated cellulose with similar properties to that obtained from a commercial industrial eucalypt pulp, producing films with high mechanical properties and low wettability. According to these properties, different applications for cellulose microfibers suspensions and films are discussed.


Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4705
Author(s):  
Ewa Kochańska ◽  
Rafał M. Łukasik ◽  
Maciej Dzikuć

The COVID-19 pandemic has set new challenges for the HoReCa industry. Lockdowns have coincided with and strongly impacted the industrial transformation processes that have been taking place for a decade. Among the most important HoReCa transition processes are those related to the rapid growth of the delivery-food market and ordering meals via internet platforms. The new delivery-food market requires not only the development of specific distribution channels, but also the introduction of appropriate, very specific food packaging. Food packaging and its functionality are defined by the administrative requirements and standards applicable to materials that have contact with food and principally through the prism of the ecological disaster caused by enormous amounts of plastic waste, mainly attributed to the food packaging. To meet environmental and administrative requirements, new technologies to produce food packaging materials are emerging, ensuring product functionality, low environmental impact, biodegradability, and potential for composting of the final product. However, predominantly, the obtained product should keep the nutritional value of food and protect it against changes in color or shape. Current social transformation has a significant impact on the food packaging sector, on one hand creating a new lifestyle for society all over the world, and on the other, a growing awareness of the negative impact of humans on the environment and increasing responsibility for the planet. The COVID-19 pandemic has highlighted the need to develop a circular economy based on the paradigm of shortening distribution channels, using local raw materials, limiting the consumption of raw materials, energy, water, and above all, minimizing waste production throughout the life cycle of products, all of which are in line with the idea of low-carbon development.


2012 ◽  
Vol 82 ◽  
pp. 32-37 ◽  
Author(s):  
Malgorzata Plonska ◽  
Wojciech A. Pisarski ◽  
Beata Wodecka-Dus ◽  
Lukasz Cienki

In the present work the influence of neodymium concentration (0-1at-%) and sintering conditions on 8/65/35 PLZT:Nd3+ ceramics were studied. All ceramic powders were synthesized by MOM technique from high purity raw materials (>99,9%), and subsequently sintered by free sintering and hot uniaxial pressing method. To analyze the powders and ceramics more the XRD, EDS SEM, and ferroelectric measurements were performed. Optical spectra were examined for all prepared samples, and their optical properties were analyzed using reflectance, excitation and luminescence measurements. The study gives a detailed account of the relationships between doping and preparing conditions on the basic physical and dielectric and optical properties of obtained ceramic materials.


Author(s):  
Marcela Spišáková ◽  
Mária Kozlovská ◽  
Jozef Švajlenka

Construction industry creates an environment for people's lives. On the other hand, construction activities have a negative impact on various aspects of the environment. It consumes natural raw materials, significantly contributes to carbon footprint, waste, etc. Appropriate choice of constructional, material, technical, technological and environmental parameters of buildings can partially reduce this negative impacts. By designing, implementing and using wood-based constructions it is possible to reduce the negative impact in the area of construction waste generation. Currently, the construction market offers a large number of construction systems of wooden buildings, which have both strengths and weaknesses. In this paper are identified construction systems of wooden buildings offered on the Slovak construction market. The aim of the paper is a detailed identification of construction waste generation during the realization of particular wooden structures and monitoring of waste generation in production factory (off site) and on construction site (on site) during the construction of wooden buildings. Based on the obtained information, the individual construction systems of wood-based constructions are compared in terms of construction waste generation


2021 ◽  
Vol 50 (5) ◽  
pp. 1267-1275
Author(s):  
Khye Er Loh ◽  
Nor Azwady Abdul Aziz ◽  
Muskhazli Mustafa ◽  
Intan Safinar Ismail

The rising concern regarding the negative impact of synthetic pesticides has led to the search for alternative means of pest control. Vermicomposting the mixture of oil palm empty fruit bunch and neem (Azadirachta indica) leaves, with the latter known to have pesticidal value, is therefore of great interest and significance to be studied. The present study was conducted to evaluate the chitinase, protease and β-1,3-glucanase activity of neem leaf-based vermicompost as an indication of its biocontrol properties. The total microbial population of different composition of the vermicompost was also investigated. The results showed that at 10% neem composition, an increment in microbial population, chitinase and protease activities was observed in the end product. A higher concentration of neem exerted a suppressive effect on the microbial population as well as enzymatic activity. This study suggested that the addition of an appropriate composition of neem leaves as one of the raw materials for vermicomposting would potentially enhance the performance of vermicompost as biofertilizer as well as biopesticide.


2021 ◽  
Vol 0 (4) ◽  
pp. 6-11
Author(s):  
I.T. Nagieva ◽  
◽  
N.I. Ali-zadeh ◽  
T.М. Nagiev ◽  
◽  
...  

In recent years, hydrogen peroxide and nitrous oxide (1) "green oxidants" – have attracted much attention of researchers as a selective oxidizing agent for the catalytic oxidation of pyridine bases. In this regard, the reaction of pyridine oxidation by hydrogen peroxide and nitrous oxide under homogeneous conditions, in the gas phase, without the use of catalysts, at atmospheric pressure, has been experimentally investigated. Areas of selective oxidation of pyridine with hydrogen peroxide and nitrous oxide have been established, and optimal conditions have been found for obtaining valuable raw materials required in the petrochemical, chemical, and pharmaceutical industries


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