Volume 8 Issue 1

Forests have long-standing relationships with humanity beyond the material aspects. Recreation is an essential human need, and forests possess intrinsic values to support such a need in direct, authentic, and emotional ways. Quality recreation experiences can lead to a greater appreciation of bioresources and deeper support for forest conservation. The forest-recreation connections should be celebrated and sustained in this age of rapid social, environmental, and technological changes.

Reactive extrusion is an attractive green route for cost-effective polymer processing, which has the potential to enhance the commercial viability of biomass-derived materials. In reactive extrusion, compatibilizers can be generated in the blend preparation through polymer-polymer grafting reactions using functionalized polymers. One very interesting new green strategy for processing is the use of intense UV-irradiation to create free radicals and controllable, ultra-fast reactions. It is reasonable to expect that the use of extrusion/irradiation green technology will be an important way to improve properties and compatibility of renewable biomass- derived polymers. We believe that in the future, many more cost-effective, sustainable extrusion/irradiation reaction processes will be developed to replace inefficient conventional biomass conversion procedures and stimulate the bioproduct-based industry.

Fluorescent semiconductor nanocrystals, also called quantum dots (QDs), have unique electronic and optical properties. One of the most useful features of QDs is that whereas their absorption spectra are broad, their emission spectra are very narrow. Different QDs can emit different wavelengths of visible light under UV excitation. QDs as a fluorescent anti-counterfeiting material have been attracting great interest in the application of specialty papers, such as security paper, banknote paper, packaging paper, etc. An anti-counterfeiting technique using QDs is one of the newest achievements in the anti-counterfeiting field. In the long run, research and development in the area of QDs anti-counterfeiting will surely create many fruitful results.

Biochar is an effective means to withdraw carbon dioxide (CO2) from the atmosphere and consequently influence the trend of global climate change. However, there still are substantial knowledge gaps for this idea to be applicable. One big question is how to produce biochar from biomass on a large scale. Our idea is to use biogas produced from agricultural wastes as thermal energy for biochar production from cheap crop residues. A continuous biogas-energy pyrolysis system has been designed and successfully piloted to utilize crop residues for biochar production.

Heartwood samples from three species of Juniperus (i.e., J. virginiana, J. occidentalis, and J. ashei) were extracted with hexane, ethanol, and methanol. The hexane and ethanol extracts were tested for antifungal activity against four species of wood-rot fungi (i.e, Gloeophyllum trabeum, Postia placenta, Trametes versicolor,and Irpex lacteus). Ashe juniper (AJ) gave the highest extract yields (6.60 to 11.27%), followed by Eastern red cedar (ERC) (4.78 to 9.56%), and then Western juniper (WJ) (4.26 to 7.32%). WJ contained the highest level of cedrol (over 60%), while AJ contained the highest level of thujopsene (over 30%). Methanol and ethanol gave the highest extract yields as well as slightly higher percentages of cedrol and widdrol. The juniper extracts were more effective against white-rot fungi than brown-rot fungi. The ethanol extracts had higher antifungal activity than the hexane extracts. The AJ extracts had the greatest bioactivity against the wood-rot fungi.

Chemi-mechanical pulping was evaluated as a potential way to prepare sugarcane bagasse fibers for papermaking. Cellulose, lignin, ash, and extractives soluble in alcohol-acetone were measured as 55.75%, 20.5%, 1.85%, and 3.25%, respectively. Fiber length, diameter, lumen cavity, and cell wall thickness were measured as 1.59 mm, 20.96, 9.72, and 5.64 µm. The chemi-mechanical pulping conditions were selected as follows: three charging levels of 10, 15, and 20% sodium sulphite, and three pulping times of 20, 30, and 40 minutes after reaching the pulping temperature. Pulping temperature was held constant at 165 °C. Different pulping conditions resulted in pulp yields between 65.38 and 84.28%. The highest yield (84.28%) was obtained using a treatment combination of 20 minutes pulping time and 10% sodium sulphite. The lowest yield (65.38%) was related to 40 minutes pulping time and 20% sodium sulphite. Pulps were refined to 300 ± 25 mL CSF, 60 gm^-2 handsheets were made, and then strength indices and optical properties of the handsheets were measured. The results showed that 20% sodium sulphite, 40 minutes pulping time, at 165 ºC can be considered as the optimum pulping conditions for bagasse CMP pulping. Tensile, tear, and burst strength indices, as well as the opacity of this pulp were measured as 39.59 Nmg^-1, 6.66 mNm²g^-1, 2.1 KPa m²g^-1, and 95.35%, respectively.

Sodium silicate causes problems in papermaking such as deposit formation, decreased retention, and lower sheet strength. Due to these problems, chemical deinking of different recycled papers furnishes including 100% ONP, 80% ONP, and 20% OMG, and a combination of 70% ONP/ 20% OMG/ 10% MOW was accomplished using an organic complexing agent which included poly-hydroxyl acrylic acid and sodium salt (PHAAS) in silicate-free conditions. PHAAS was utilized at four levels of 0.3, 0.5, 0.7, and 1% (based on oven-dry weight of recycled paper) rather than sodium silicate. The optical and physical properties of deinked pulp were compared to control pulp (conventional deinking containing 2% sodium silicate). The results showed that the paper brightness was improved and the yellowness, dirt count, and dirt area were decreased significantly by increasing PHAAS charge up to 0.9%. Also, in different recycled paper furnishes above mentioned, using different charges of PHAAS had different effects on paper opacity. Using different charges of PHAAS (especially 0.7 to 0.9%) decreased paper caliper, increased paper air resistance, increased freeness, and gave similar or slightly better paper tear indices. Differences of tear indices were not significant at confidence level of 99%. Based on the present research, the use of 0.7 to 0.9% PHAAS in place of sodium silicate is advisable because of the better quality of final papers compared to conventional deinking process.

This paper presents the results of trials to evaluate the color-stripping behaviour of offset printing colors and the effect of coating on deinking performance. Oil-based four-color inks were separately printed as base printing on coated and uncoated white poster paper, and then extensive pulping and deinking processes were carried out. Standard offset printings were conducted on paper samples using cyan, magenta, yellow, and black colors (CMYK), and the effects of deinking efficiency on the removal of each color were analysed. The pulps were made at Micro-Maelstrom Laboratory Pulper at specified conditions with and without bleaching agents. Formamidin sulfinic acid and hydrogen peroxide formulation were used as reductive and oxidative bleaching agents, respectively. Flotation deinking and thickening of pulp were practiced using Degussa flotation and thickening cell. The changes in the optical properties, such as brightness, whiteness, and color value (CIE L⃰, a⃰ b⃰) of deinked pulp were determined. It was found that optical properties of color-stripped pulps from coated papers were better than that of uncoated office papers. However, yield was quite low in coated papers since fillers were lost during flotation process. Cyan color was found to be the most difficult one in four main color printing inks stripping out in deinking process.

Dried Distillers Grain with Solubles (DDGS) was evaluated as a bio-based fiber reinforcement. Composites of high density polyethylene (HDPE) composed of 25% by weight DDGS and either 0% or 5% by weight of maleated polyethylene (MAPE) were produced by twin screw compounding and injection molding. An improved DDGS bio-filler was produced by solvent treating DDGS (STDDGS). Injection-molded test specimens were evaluated for their tensile, flexural, impact, and thermal properties. Composite blends composed of STDDGS were superior to their DDSG counterparts. Composites made with STDDGS and MAPE had significantly improved tensile and flexural properties compared to neat HDPE. Impact strength of all composites was similar and lower than neat HDPE. Soaking of tensile bars of the various PE-DDGS blends in distilled water for 28 days altered their physical, color, and mechanical properties. Differential scanning calorimetery and thermogravimetric analysis were conducted on neat HDPE and DDGS composites to evaluate their thermal properties.

An attempt was made to reclaim and recover palm oil mill effluent (POME) for water reuse using tubular ultrafiltration (UF) and reverse osmosis (RO) membranes. The reclaimed water was compared with the final discharged water of the local mill. The raw POME was first subjected to a physical pre-treatment process to remove the content of organic matter and suspended solids. The pre-treatment process was coupled with membrane technology (UF and RO) to reclaim the clean water from POME. From the combined techniques of UF (5 bar) and RO (30 bar) the results showed that the turbidity and BOD5 were reduced by 99% and 98.9%, respectively. Compared to the final discharged POME, this suggested method gives a significant difference in BOD5 and turbidity. The final permeate of RO was found to comply with the standards for water reuse. Therefore, the combined UF and RO method is a viable alternative and has a great potential for use in the palm oil industry.