scholarly journals Lignin as a UV Light Blocker—A Review

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1134 ◽  
Author(s):  
Hasan Sadeghifar ◽  
Arthur Ragauskas
Keyword(s):  
Molecular Weight ◽  
Functional Groups ◽  
Broad Spectrum ◽  
Uv Light ◽  
Complex Structure ◽  
Pulp And Paper ◽  
Transparent Film ◽  
Uv Blocking ◽  
Pulp And Paper Industries ◽  
Modified Forms

Lignin is the by-product of pulp and paper industries and bio-refining operations. It is available as the leading natural phenolic biopolymer in the market. It has chromophore functional groups and can absorb a broad spectrum of UV light in range of 250–400 nm. Using lignin as a natural ingredient in sunscreen cream, transparent film, paints, varnishes and microorganism protection has been actively investigated. Both in non-modified and modified forms, lignin provides enhancing UV protection of commercial products with less than a 10% blend with other material. In mixtures with other synthetic UV blockers, lignin indicated synergic effects and increased final UV blocking potential in compare with using only synthetic UV blocker or lignin. However, using lignin as a UV blocker is also challenging due to its complex structure, polydispersity in molecular weight, brownish color and some impurities that require more research in order to make it an ideal bio-based UV blocker.

scholarly journals Utilization of Organic Mixed Biosludge from Pulp and Paper Industries and Green Waste as Carbon Sources in Blast Furnace Hot Metal Production

2021 ◽  
Vol 13 (14) ◽  
pp. 7706
Author(s):  
Tova Jarnerud ◽  
Andrey V. Karasev ◽  
Chuan Wang ◽  
Frida Bäck ◽  
Pär G. Jönsson
Keyword(s):  
Blast Furnace ◽  
Carbon Sources ◽  
Hydrothermal Carbonization ◽  
Pulp And Paper ◽  
Hot Metal ◽  
Technological Parameters ◽  
Metal Production ◽  
Green Waste ◽  
Fuel Rate ◽  
Pulp And Paper Industries

A six day industrial trial using hydrochar as part of the carbon source for hot metal production was performed in a production blast furnace (BF). The hydrochar came from two types of feedstocks, namely an organic mixed biosludge generated from pulp and paper production and an organic green waste residue. These sludges and residues were upgraded to hydrochar in the form of pellets by using a hydrothermal carbonization (HTC) technology. Then, the hydrochar pellets were pressed into briquettes together with commonly used briquetting material (in-plant fines such as fines from pellets and scraps, dust, etc. generated from the steel plant) and the briquettes were top charged into the blast furnace. In total, 418 tons of hydrochar briquettes were produced. The aim of the trials was to investigate the stability and productivity of the blast furnace during charging of these experimental briquettes. The results show that briquettes containing hydrochar from pulp and paper industries waste and green waste can partially be used for charging in blast furnaces together with conventional briquettes. Most of the technological parameters of the BF process, such as the production rate of hot metal (<1.5% difference between reference days and trial days), amount of dust, fuel rate and amount of injected coal, amount of slag, as well as contents of FeO in slag and %C, %S and %P in the hot metal in the experimental trials were very similar compared to those in the reference periods (two days before and two days after the trials) without using these experimental charge materials. Thus, it was proven that hydrochar derived from various types of organic residues could be used for metallurgical applications. While in this trial campaign only small amounts of hydrochar were used, nevertheless, these positive results support our efforts to perform more in-depth investigations in this direction in the future.

Structure and Solution Properties of High Molecular Weight Butadiene-Styrene Copolymers

1957 ◽  
Vol 30 (1) ◽  
pp. 315-325
Author(s):  
R. B. MacFarlane ◽  
L. A. McLeod
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Complex Structure ◽  
Mixed Solvents ◽  
Solution Time ◽  
Solution Viscosity ◽  
Solution Properties ◽  
Molecular Weight Range ◽  
Viscosity Measurements ◽  
Commercial Practice

Abstract Production of high molecular weight copolymers of butadiene and styrene for use in oil-extended rubbers has aroused interest in the solution properties of copolymers above the molecular weight range commonly encountered in commercial practice. It has been observed that solubility of such polymers in toluene is a time-dependent phenomenon and the apparent solubility can increase continuously, in the absence of agitation, for as long as 800 hours. Although a standard Harris cage solubility test may show the presence of 50% gel, other properties do not confirm the presence of any appreciable quantities of insoluble material. Mild agitation rapidly promotes almost complete solubility. Dilute solution viscosity measurements are very misleading unless the influence of solution time is recognized and apparent intrinsic viscosities rise progressively with time of contact of the sample with solvent. This time-dependence of solution has been found to occur at conversions higher than 50% and is also a function of the amount of modifier used in the polymerization recipe. It has not been possible to shorten the solution time for viscosity measurements by mild heating or gentle agitation. Mixed solvents cause a change in the amount of increase of the apparent intrinsic viscosity but do not shorten the time to equilibrium. Measurement of the slope constant in the Huggins viscosity equation indicate that these solubility and viscosity effects coincide with the appearance of a marked degree of branching in the polymer molecules. The effect is, therefore, interpreted as being caused by the relatively slow disentanglement of molecules of complex structure.

Capital Deepening and Technological Change: The Canadian Pulp and Paper Industry 1940–1960

1971 ◽  
Vol 1 (3) ◽  
pp. 159-166 ◽  
Author(s):  
G. H. Manning ◽  
G. Thornburn
Keyword(s):  
Technological Change ◽  
Production Function ◽  
Chemical Industry ◽  
Paper Industry ◽  
Pulp And Paper Industry ◽  
Plant Size ◽  
Pulp And Paper ◽  
Capital Deepening ◽  
Forest Industries ◽  
Pulp And Paper Industries

The pulp and paper industry is generally considered the most technologically progressive of the forest industries. A study employing Solow's method indicated a rise in the index of technological change of 50% between 1940 and 1960. This compares with a 547% increase for the chemical industry. Derivation of the capital production function for the pulp and paper industries shows that all increases in productivity, 1940–1960, were due to change in technology. There is also some indication that optimal plant size has been reached.

scholarly journals Neutralization of Acidic Wastewater from a Steel Plant by Using CaO-Containing Waste Materials from Pulp and Paper Industries

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2653
Author(s):  
Tova Jarnerud ◽  
Andrey V. Karasev ◽  
Pär G. Jönsson
Keyword(s):  
Fly Ash ◽  
Pulp And Paper ◽  
Waste Materials ◽  
Paper Mills ◽  
Steel Mills ◽  
Lime Mud ◽  
Set Up ◽  
Pulp And Paper Industries ◽  
The Given ◽  
Acidic Wastewater

In this study, CaO-containing wastes from pulp and paper industries such as fly ash (FA) and calcined lime mud (LM) were utilized to neutralize and purify acidic wastewaters from the pickling processes in steel mills. The investigations were conducted by laboratory scale trials using four different batches of wastewaters and additions of two types of CaO-containing waste materials. Primary lime (PL), which is usually used for the neutralization, was also tested in the same experimental set up in the sake of comparison. The results show that these secondary lime sources can effectively increase the pH of the acidic wastewaters as good as the commonly used primary lime. Therefore, these secondary lime sources could be potential candidates for application in neutralization processes of industrial acidic wastewater treatment. Moreover, concentrations of metals (such as Cr, Fe, Ni, Mo and Zn) can decrease dramatically after neutralization by using secondary lime. The LM has a purification effect from the given metals, similar to the PL. Application of fly ash and calcined lime mud as neutralizing agents can reduce the amount of waste from pulp and paper mills sent to landfill and decrease the need for nature lime materials in the steel industry.

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