Search

ispartof: JOURNAL OF ENERGY CHEMISTRY vol:70 pages:492-501 status: published

Bio-based additives received significant attention in pulp and paper properties improvement. For this, the most cited biochemical Cellulose Nano Fibrils (CNFs) and Cationic Starch (CS) were experimentally compared with the most declared synthetic chemical, Cationic Polyacrylamide (CPAM). SEM images showed better paper surface filling by the utilization of the chemicals. The three studied polymers, in solely or combination mechanism, improved mainly bagasse pulp and paper properties compared to the blank sample, except for pulp drainage, which decreased by CNFs to lower volumes presumably due to its intrinsic characteristics. Cationic polymers (CP) compared to CP/CNFs approaches increased pulp retention and drainage but decreased paper density and strengths. The best pulp retention and drainage achieved by CS followed by CPAM, while paper air persistency, density, and strength properties evaluated highest by CP/CNFs followed by CNFs. Generally, CS revealed a more significant improvement in pulp and paper properties than CPAM either with or without CNFs.

High per- and polyfluorinated alkyl substance (PFAS) concentrations have been detected in agricultural soils in Southwest Germany. Discharges of PFAS-contaminated paper sludge and compost are suspected to be the cause of the contamination. Perfluorinated carboxylic acids (PFCAs) have been detected also in groundwater, drinking water, and plants in this area. Recently, previously unknown compounds have been identified by high-resolution mass spectrometry (HRMS). Major contaminants were polyfluorinated dialkylated phosphate esters (diPAPs) and N-ethyl perfluorooctane sulfonamide ethanol–based phosphate diester (diSAmPAP). In this study, HRMS screening for PFAS was applied to 14 soil samples from the contaminated area and 14 impregnated paper samples which were from a similar period than the contamination. The paper samples were characterized by diPAPs (from 4:2/6:2 to 12:2/12:2), fluorotelomer mercapto alkyl phosphates (FTMAPs; 6:2/6:2 to 10:2/10:2), and diSAmPAP. In soil samples, diPAPs and their transformation products (TPs) were the major contaminants, but also FTMAPs, diSAmPAP, and their TPs occurred. The distribution patterns of the carbon chain lengths of the precursor PFAS in soil samples were shown to resemble those in paper samples. This supports the hypothesis that paper sludge is a major source of contamination. The presence of major degradation products like PFCAs, FTSAs, or PFOS and their distribution of carbon chain lengths indicate the activity of biotic or abiotic degradation processes and selective leaching processes from the upper soil horizons. Graphical abstract Supplementary Information The online version contains supplementary material available at 10.1007/s00216-021-03463-9.

The potential of alkaline cellulo-xylanolytic enzymes from non-pathogenic Bacillus subtilis strain was tested for deinking of photocopier waste paper. Cellulase and xylanase play a crucial role in deinking of different types of waste paper. Partial purification of cellulo-xylanolytic enzymes was carried out using ultrafiltration followed by ammonium sulfate precipitation. The ultrafiltered enzyme was used for deinking the photocopier waste paper along with chemical deinking. An enzyme dose of 0.6 IU/g and reaction time of 60 min for ultrafiltered cellulo-xylanolytic enzyme significantly increased deinking efficiency, tear index (9.52%) and folding endurance (5±2%) as compared to chemical deinking. There was improvement in strength properties such as tear index and double-fold along with freeness of pulp (18%). There was slight decrease in tensile index (0.6%) and burst index (16%) while ISO brightness remained unaffected. Enzymatic deinking (74.3%) by ultrafiltered cellulo-xylanolytic from Bacillus subtilis was found significant over conventional chemical deinking.

The objective of this study was to check the potential of crude xylano-pectinolytic enzymes in bleaching of rice straw pulp, in order to reduce the toxic waste load for managing the environmental pollution. The xylano-pectinolytic enzymatic bleaching step for delignification was found to be most effective at pulp consistency 1:10 g/ml, xylanase:pectinase dose of 9:4 IU/ml, pH 8.5 and treatment time 180 min at temperature of 55 °C, and resulted in lowering of kappa number of the rice straw pulp by 15.29%. In subsequent bleaching stages, this enzymatic pre-bleaching treatment also resulted in 30% reduction of active chlorine dioxide dose without any loss of optical properties. Significant improvement in various physical properties of the enzymes treated pulp, tear index (15.43%), breaking length (11.11%), double fold number (25.92%), burst index (9.88%) and viscosity (13.63%), and Gurley porosity (39.86%) was also noticed. This approach resulted in reduction of BOD and COD values by 21.07% and 26.57%, respectively. This is the first study on the use of crude xylano-pectinolytic enzymes for bio-bleaching of rice straw pulp.

Nanofibrillated films based on TEMPO-oxidized cotton linters were applied to reduce the hydrophilic properties of paper. For this purpose, aqueous dispersions of nanofibrillated cellulose of different composition: 1 and 3% of nanofibrillated cellulose, up to 13% of CaCO3 and/or Al(OH)3, up to 20% of propane-1,2-diol (glycol), and up to 21% of TEMPO-oxidized cotton linters were coated on the model paper, without additional adhesive. The pristine model paper and papers coated with nanofibrillated cellulose-based composite films were characterized in terms of water absorptiveness by COBB method and water drop contact angle measurements. The surface appearance was characterized by scanning electron microscopy (SEM) and surface chemistry by infrared spectroscopy with Fourier transform and attenuated total reflection (ATR-FTIR). Additionally, optical properties, i.e. measurement of reflection curves and CIE degrees of whiteness, were determined according to appropriate standards. For all papers coated with nanofibrillated cellulose-based films, depending on the composition of the dispersions, a decrease in sorption properties was achieved, without changes in optical properties and surface morphology of the paper compared to the pristine paper.

There is a pressing need around the world to develop novel functional biodegradable materials to separate oil/water mixtures and emulsions completely. Recently, superhydrophilicity and underwater superoleophobicity materials have been attracted attention due to their high efficiency in oil/water separation. However, it is still a challenge to prepare materials that combine oil/water separation and water purification in an environment-friendly way. In this work, biodegradable starch-based nanospheres (SNPs) coated filter paper was prepared in a low-cost, simple, and environmentally friendly manner. The SNPs coating could not only help to change the wettability of the substrate material but also build the hierarchical micro and nano structures which are conducive to separation and purification process. After modification by coating SNPs, the filter paper exhibited excellent performance in a wide range of oil/water mixtures or emulsions separation and the wettability of the filter paper could be regulated by adjusting the pH value. The modified filter paper presented good recyclability after several separation process. Furthermore, the as-prepared filter paper could also remove water-soluble contaminants during the oil/water separation process, thus realizing to combine separation and purification process in one single step. This biodegradable starch-based separating material with good separation performance, stability and recyclability has significant application potential in practical separation and purification process.

Starch and derivatives thereof have proven their usefulness in paper coating processes. Among these derivatives, cationic starch has been widely used in the paper industry as a flocculation, dispersion and ink fixing agent. In another context, nanoscale cellulosic materials have been shown to improve the strength, retention of fillers, the barrier properties of packaging paper products, and printing qualities. This review summarizes the recent studies on the general components used in paper coating, describes the conventional and alternative synthetic processes of cationic starches and nanocellulose, and deals with their current and potential applications in papermaking, focusing primarily on surface treatments. Moreover, environmental applications have been considered to expand the understanding and usefulness of these materials. Further research on modified polysaccharides is encouraged to replace, in a feasible way, petro-based components of coating formulations, and to provide paper surfaces with new properties.

Application of barrier dispersion coatings on paperboards, which must have proper moisture and grease resistance for food applications, has always been an interesting subject for the packaging industry. In this study, paperboards were coated with a novel dispersion barrier coating prepared through mixing soy protein isolate (SPI) and polyethylene wax (PE-wax). Different characterization methods were used to study the effects of coating and its composition on the physical, mechanical, and barrier characteristics of paperboards. The results indicated that the incorporation of PE-wax into the coating formulation caused significant reduction of the viscosity of coating slurries. It had no effect on the coating weight of the samples but increased the thickness of the coated paperboards as compared with those coated with SPI only. The increase of the wax content led to a reduction of 5-16% in the tensile strength values in comparison with the uncoated paperboards. Barrier characteristics, i.e., water vapor permeability (WVP), surface wettability, and water resistance, improved by adding PE-wax. In addition, it was found that there was a critical level for the addition of PE-wax, 50% of SPI, as no oil migration was detected when the paperboards coated with SPI coatings contained less than 50% PE-wax.

In this study, action of ultrafiltered xylano-pectinolytic enzymes from a bacterial strain has been evaluated for bleaching of rice straw soda-anthraquinone pulp. Maximum bio-bleaching effect and release of non-cellulosic impurities were noticed with xylano:pectinolytic enzymes dose of 6.0:2.1-IU/g pulp, treatment time of 180 min at 10% pulp consistency, pH 8.5, and temperature 55 °C. Microscopic images of bio-bleached rice straw pulp also confirmed the efficacy of ultrafiltered enzymes, as bleaching agent. This bio-bleaching treatment resulted in 15.38% and 32% reduction in kappa number and active chlorine dioxide dose, respectively, along with increase in various physical properties, burst index (12.50%), tear index (19.07%), breaking length (14.30%), double fold number (26.31%), Gurley porosity (45.32%) and viscosity (16.17%). This bio-bleaching approach not only improved the pulp quality but also reduced environmental pollution load by decreasing effluent parameters values of BOD and COD by 23.67% and 27.44%, respectively. This study indicates that use of ultrafiltered xylano-pectinolytic synergism for rice straw pulp bleaching will ultimately help in making the process eco-friendly, along with better quality pulp. This is the first report on use of ultrafiltered xylanase and pectinase, produced from a bacterial isolate, for bleaching of rice straw pulp.

The pulp bleaching process removes or transforms the chromophore groups in the pulp, so that the final product reaches a desired brightness. However, this chemical treatment inevitably results in yield loss. Therefore, the objective of this work was to quantify the yield loss caused during the bleaching of kraft pulp of Pinus radiata delignified with oxygen. The material was submitted to three distinct ECF sequences (D0(EPO)D1D2, D0(EPO)D1P, and Z/EDP). At the end of each bleaching stage, the pulp brightness and the loss of gravimetric yield of the process were determined, and the generated filtrates were collected. From these filtrates, the pollutant load of the effluent was determined by measuring the content of total dissolved solids, the chemical oxygen demand, the concentration of total organic carbon carbon, and the adsorbable organic halogens. Among the whole sequences, the Z/EDP sequence had the lowest gravimetric yield, the highest pollutant load in the collected filtrate, and lowest potential for adsorbable organic halogens generation. There was good correlation between the loss of yield from the bleaching process and the organic load of the generated effluent; and among the techniques studied, the quantification of total organic carbon was the most appropriate method for the indirect quantification of the yield loss during the bleaching process of the studied material.

This paper reports the performance enhancement benefits in diamond turning of the silicon wafer by incorporation of the surface defect machining (SDM) method. The hybrid micromachining methods usually require additional hardware to leverage the added advantage of hybrid technologies such as laser heating, cryogenic cooling, electric pulse or ultrasonic elliptical vibration. The SDM method tested in this paper does not require any such additional baggage and is easy to implement in a sequential micro-machining mode. This paper made use of Raman spectroscopy data, average surface roughness data and imaging data of the cutting chips of silicon for drawing a comparison between conventional single-point diamond turning (SPDT) and SDM while incorporating surface defects in the (i) circumferential and (ii) radial directions. Complementary 3D finite element analysis (FEA) was performed to analyse the cutting forces and the evolution of residual stress on the machined wafer. It was found that the surface defects generated in the circumferential direction with an interspacing of 1 mm revealed the lowest average surface roughness (Ra) of 3.2 nm as opposed to 8 nm Ra obtained through conventional SPDT using the same cutting parameters. The observation of the Raman spectroscopy performed on the cutting chips showed remnants of phase transformation during the micromachining process in all cases. FEA was used to extract quantifiable information about the residual stress as well as the sub-surface integrity and it was discovered that the grooves made in the circumferential direction gave the best machining performance. The information being reported here is expected to provide an avalanche of opportunities in the SPDT area for low-cost machining solution for a range of other nominal hard, brittle materials such as SiC, ZnSe and GaAs as well as hard steels.

In this study, Rhododendron luteum and Rhododendron ponticum were evaluated as raw material for pulp and paper production. 12 different sodium borohydride (NaBH4) added cooking trials were performed for each sample and kraft method was used for pulp production. Pulp properties, such as yield, kappa number and viscosity, and physical properties, such as breaking length and burst index, were determined for each trial. Besides, the effects of active alkali and NaBH4 on the pulp and paper properties were also examined. Optimum cooking conditions were obtained by using 18 % active alkali for NaBH4-free cooking experiments and 0.5 % NaBH4 and 18 % active alkali for NaBH4-added cooking experiments. In NaBH4-added pulping condition, the screened yield, kappa number and viscosity of R. luteum were found to be 43.4 %, 40.1 and 949 cm3/g1, respectively. The respective values for R. ponticum were 41.9 %, 44.5 and 885 cm3/g1. The screened yields of R. luteum and R. ponticum increased by about 2.8 % and 5.3 %, respectively, with 5 % addition of NaBH4 compared to NaBH4-free cooking experiments. Furthermore, with the addition of NaBH4, the kappa numbers decreased while the viscosity increased. The physical properties of the produced papers were also improved by using NaBH4 in cooking liquor. According to the obtained results, it was found that R. luteum and R. ponticum species can be evaluated for pulp and paper production., U ovom je radu istražena mogućnost uporabe biljaka Rhododendron luteum i Rhododendron ponticum kao sirovine za proizvodnju celuloze i papira. Za svaki uzorak provedeno je 12 različitih ispitivanja kuhanja s natrijevim borhidridom (NaBH4), a celuloza je proizvedena kraft postupkom. Za svako ispitivanje određena su svojstva celuloze poput prinosa, kappa broja i viskoznosti, te fizička svojstva kao što su duljina lomljenja i indeks pucanja papira. Osim toga, ispitani su učinci aktivne lužine i NaBH4 na svojstva celuloze i papira. Optimalni uvjeti kuhanja postignuti su upotrebom 18 % aktivne lužine za eksperimentalno kuhanje bez NaBH4 i upotrebom 0,5 % NaBH4 i 18 % aktivne lužine za eksperimentalno kuhanje s dodatkom NaBH4. U proizvodnji celuloze iz biljke R. luteum s dodatkom NaBH4 utvrđeno je da prinos prosijavanja iznosi 43,4 %, da je kappa broj 40,1, a viskoznost 949 cm3/g, dok su vrijednosti za celulozu dobivenu iz biljke R. ponticum redom 41,9 %, 44,5 i 885 cm3/g. Prinos prosijavanja biljaka R. luteum i R. ponticum uz dodatak 5 % NaBH4 povećao se oko 2,8 % i 5,3 % u usporedbi s eksperimentalnim kuhanjem bez dodatka NaBH4. Nadalje, uz dodatak NaBH4 smanjuju se kappa brojevi, a viskoznosti se povećavaju. Fizička svojstva proizvedenih papira također se poboljšavaju dodavanjem NaBH4 tekućini za kuhanje. Iz dobivenih je rezultata utvrđeno da se biljke R. luteum i R. ponticum mogu upotrebljavati u proizvodnji celuloze i papira.

A soft body area sensor network presents a promising direction in wearable devices to integrate on-body sensors for physiological signal monitoring and flexible printed circuit boards (FPCBs) for signal conditioning/readout and wireless transmission. However, its realization currently relies on various sophisticated fabrication approaches such as lithography or direct printing on a carrier substrate before attaching to the body. Here, we report a universal fabrication scheme to enable printing and room-temperature sintering of the metal nanoparticle on paper/fabric for FPCBs and directly on the human skin for on-body sensors with a novel sintering aid layer. Consisting of polyvinyl alcohol (PVA) paste and nanoadditives in the water, the sintering aid layer reduces the sintering temperature. Together with the significantly decreased surface roughness, it allows for the integration of a submicron-thick conductive pattern with enhanced electromechanical performance. Various on-body sensors integrated with an FPCB to detect health conditions illustrate a system-level example.

A two-step process involving coagulation-flocculation followed by solar photocatalysis – based Advanced Oxidation Process (AOP) using TiO2-Reduced Graphene Oxide (TRGO) nanocomposite as catalyst ha...

The use of nanocelluloses is being conducted for the most diverse applications. Their performance as coating agent has been mainly explored to improve barrier properties, as they emerge as perfect candidate for plastic substitution, but it is also important to explore their potential to improve printing quality. In the present work, the influence of different nanocelluloses, obtained through mechanical, enzymatic, TEMPO-mediated oxidation and carboxymethylation treatments, in the coating process and inkjet printability of office papers was assessed. The results revealed that the cellulose nanofibrils are better for printability than the microfibrils. But the size and charge of the former must be taken into account, since fibrils of very small size penetrate the paper structure, dragging the pigments from the surface, and very anionic nanofibrils can also have negative influence on the optical density. Besides, an interesting synergy between surface-sizing starch and the cellulose nanofibrils was found to occur as the latter closed the paper structure, which prevented starch from penetrating, while potentiating both of their positive effects on ink pigment entrapment. An additional study of characterization of inkjet pigments was also performed.

A bleached kraft pulp mill discharging effluent to the Mattagami River in northern Ontario, Canada, closed after almost 90 yr of operation. During its operation, effluent from the mill influenced biota in the downstream areas. To assess shifts in the reliance of biota from mill-derived nutrients, the isotopic composition (δ13 C and δ15 N) of white sucker (Catostomus commersoni) muscle and whole mayflies (Hexagenia sp.) were compared before (1990s) and after the pulp mill's closure (2012-2014). To better understand other potential sources of spatial and temporal change, samples from 3 other tributaries in the basin with dams, ongoing pulp mill operations, sites receiving sewage, and at several reference sites were collected and compared. Irrespective of time period, biota collected at sites downstream of both dams and active pulp mills tended to have elevated δ13 C values, but variable changes in δ15 N (negligible in most cases) when compared with upstream samples. The isotopic composition of mayflies varied at reference sites over time, with decreasing values of δ13 C and δ15 N (mayflies only) with increasing depth, and there was evidence of lower δ13 C in fish after the pulp mill closure. Overall, these results suggest the importance of long-term, regional-scale measurements for documenting the effects of stressors on nutrient use by aquatic species. Environ Toxicol Chem 2020;39:1207-1218. © 2020 SETAC.

Paper-based packaging is widely employed in industries ranging from food to beverages to pharmaceuticals because of its attractive advantages of biodegradability, recyclability, good strength, low cost, and lightweight. However, paper products usually have poor water barrier resistance properties because of paper and fibers porous microstructure. In this study, an ecofriendly water-resistant (hydrophobic) oil from biological origin, namely, palm kernel oil (PKO) was used to coat paper by using a facile and cost-effective dip-casting approach. PKO formulation was prepared by mixing with a solvent and furfuryl alcohol (FA). The water resistance, structural properties, and thermal and mechanical properties of the coated papers obtained under different processing conditions were reported and compared to understand the performance of coated paper. Contact angle (CA), Fourier transform infrared (FTIR), and thermal gravimetry (TGA) were used for analysis and characterization of coated papers. Data from contact angle measurements showed that the PKO formulation could considerably improve the liquid water barrier property of the paper, with a measured water contact angle (CA) of ∼120° and reduce the water vapor transmission rate (WVTR) by 22%. This novel, green, low-cost, and water-resistant paper coating made with biological and biodegradable oil is a potential candidate for replacing petroleum-based coatings used in a broad range of applications and will also be able to make an additional full use of the palm kernel oil.

In the present article we report a new hybrid microfluidic device (hyFlow) comprising a disposable paper electrode and a three-dimensional (3D) printed plastic chip for the electrochemical detection of a magnetic bead-silver nanoparticle (MB-AgNP) bioconjugate. This hybrid device evolved due to the difficulty of incorporating micron-scale MBs into paper-only fluidic devices. Specifically, paper fluidic devices can entrap MB-containing conjugates within their cellulose or nitrocellulose fiber matrix. The hyFlow system was designed to minimize such issues and transport MB conjugates more efficiently to the electrochemical detection zone of the device. The hyFlow system retains the benefit of fluid transport by pressure-driven flow, however, no pump is required for its operation. The hyFlow device is capable of detecting either pre-formed MB-AgNP conjugates or conjugates formed in-situ formation. The detection limit of AgNPs using this device is 12 pM, which represents just 22 AgNPs per MB.

AIMS: The utilization of micro‐organisms in pulp and paper industries has proved biobleaching technology as an environmentally friendly alternative to the conventional approach. In this paper, the effect of actinobacterial fermentation broth on pulp biobleaching has been investigated. METHODS AND RESULTS: Actinobacterial colonies were isolated from lignocellulose‐rich soil samples and screened for xylanase production and bleaching activity. The most efficient isolate in bleaching activity showed 100% similarity to Streptomyces rutgersensis. Pulp treatment with 5‐day fermentation broth of this strain showed up to 7% increase in brightness (30°C for 6 h, pH (5–7)) compared to untreated (control) pulp. Also, after 60 min biotreatment, significant reduction (12·5%) in consumption of bleaching chemicals was achieved to obtain final brightness of 55%. CONCLUSION: Actinobacterial fermentation broth can be considered as a rich source of effective biobleaching agents which may be considered as environmental friendly and cost‐effective technique in comparison with traditional method. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings showed ability of S. rutgersensis UTMC 2445 in bleaching chemomechanical paper pulp. Also, two strains of Saccharothrix, a rare actinobacterium, with biobleaching activity were introduced. In the proposed method, there is no need to use purified enzymes, and biobleaching process can be done using the fermentation broth.

The main objective of this study is the evaluation of RPPW anaerobic digestion feasibility at laboratory scale under Mesophilic condition. The experiment is conducted using a two-stage biofilm digester of 5 L capacity with mobile support material. Anaerobic treatment of wastewater from recycled pulp and paper industry in Morocco was tested using a laboratory-scale anaerobic biofilm digester that operated under mesophilic conditions over a 70-day. Chemical oxygen demand (COD) efficiency, volatile and total solid (VS, TS) elimination of the substrate during the process were: 78%, 52% and 48% respectively. The system was stable throughout its operating cycle with an optimum pH (7.24), alkalinity (1750 mg CaCO3/L) and a volatile fatty acid value (760 mg/L). The experimental daily biogas production measured reaches a value of 5 L/day with a composition of 71% methane, 27.6% carbon dioxide, 0.2 oxygen and 7713 ppm of the H2S. The study results show that the anaerobic biofilm reactor is a suitable technique for recycled pulp and paper wastewater (RPPW) treatment. The reactor shows high performances in terms of process stability, removal efficiency (> 70%) and biogas production. Anaerobic digestion is an efficient waste treatment technology that uses natural anaerobic decomposition to reduce the volume of waste while producing biogas. However, research is needed to strengthen microbial metabolism, biochemistry and the functioning of the rector to improve biogas production. The RPPW AD experiment with biofilm digester technology was stable throughout the operation period. The digester knows an overloaded in the last phase of the experiment which leads to an inhibition of biogas production.

The article is devoted to the consideration of the possibility of using fullerene-containing water as part of humic growth-stimulating preparations for agriculture with the addition of yeast production waste. More recently, the problems of the economy and the environment were perceived as opposite. Currently, there is a need for a mutually dependent and mutually beneficial combination of economic and environmental interests, which was the basis for this study. The analysis of the wastewater of the yeast-producing enterprise shows the presence of a large number of chemical and organic substances that pose a certain danger to the environment, but are useful after processing waste for use in agriculture. The largest number of substances is found in waste, after the stage of production of pure culture. The experiment shows that the use of structured water in combination with biologically active waste from the production of bread yeast obtained on the basis of the Saccharomyces cerevisiae strain increases the yield of grain crops. Based on the established fact of a wide and universal spectrum of biological activity of the water-carbon structure of hydrated fullerenes, according to patent and scientific and technical literature, they have not been widely tested as plant growth regulators. We will investigate the interaction of substances with water structured with fullerenes, the effect of surfactants on the formation and stability of emulsified humates with film-forming agents, the adhesive properties of the components, the effect of concentrated yeast fermentation liquid separated after the stage of growing a pure culture of baking yeast, the effect of both a fullerene-like structure – shungite of natural origin and hydrated fullerenes – highly stable finely dispersed aqueous solutions of native fullerenes (have the properties of lyophobic molecular colloidal systems) on grain yield, protection of vegetative plants. The result of the work will be the substantiation of the principles of the methodology for the application of nanostructured substances for use in biotechnologies of multifunctional highly effective drugs for agriculture with biologically active additives., Стаття присвячена розгляду питання про можливість застосування фуллереновмістної води в складі гуміновмісних ростостимулюючих препаратів для сільського господарства з додаванням відходів дріжджового виробництва. Зовсім недавно проблеми економіки та екології сприймали як протилежні. В даний час виникла необхідність взаємообумовленого і взаємовигідного поєднання економічних і екологічних інтересів, що стало основою для проведення даного дослідження. Аналіз стічних вод підприємства, що виробляє дріжджі показує наявність великої кількості хімічних і органічних речовин, які становлять певну небезпеку для навколишнього середовища, але представляє корисність після переробки відходів для використання в сільському господарстві. Найбільша кількість речовин знаходиться у відходах, після етапу виробництва чистої культури. В експерименті показано, що застосування структурованої води в поєднанні з біологічно активними відходами виробництва хлібних дріжджів, отриманими на основі штаму Saccharomyces cerevisiae збільшують врожайність зернових культур. Виходячи зі встановленого факту широкого і універсального спектра біологічної активності водно-вуглецевої структури гідратованих фулеренів, за даними патентної та науково-технічної літератури, вони широко не випробовувалися як регулятори росту рослин. Нами буде досліджено взаємодію речовин зі структурованою фулеренами водою, досліджено вплив поверхнево-активних речовин на утворення та стабільність емульгованих гуматів з плівко утворювачами, адгезивні властивості компонентів, вплив концентрованої бродильної рідини дріжджів відсепарованої після стадії вирощування чистої культури хлібопекарських дріжджів, випробувано вплив як фулереноподібної структури-шунгіту природного походження так і гідратованих фулеренів - високостабільних дрібнодисперсних водних розчинів нативних фулеренів (мають властивості ліофобних молекулярно-колоїдних систем) на врожайність зернових, захист вегетуючих рослин. Результатом роботи буде обґрунтування принципів методології застосування наноструктурних речовин для використання в біотехнологіях багатофункціональних високоефективних препаратів для сільського господарства з біологічно активними добавками.

Significance Most shape-morphing materials rely on nonrenewable fossil resources or finely extracted biomaterials, which need strict reaction control, elaborate processing equipment, or prefabricated templates to achieve controllable transformation. To circumvent these challenges, we developed an eco-friendly and scalable strategy for programmable shape evolution that integrates easy-to-process pollen biomass with cost-effective digital printing. Using this approach, specific geometrical features and architectures were customized to build complex materials with user-defined, shape-morphing abilities. These fabrication efforts were complemented by computational simulations to build quantitative and mechanistic insights into the biomaterial’s characteristics for creating complex shapes with methods that are suitable for scalable manufacturing., We demonstrate how programmable shape evolution and deformation can be induced in plant-based natural materials through standard digital printing technologies. With nonallergenic pollen paper as the substrate material, we show how specific geometrical features and architectures can be custom designed through digital printing of patterns to modulate hygrophobicity, geometry, and complex shapes. These autonomously hygromorphing configurations can be “frozen” by postprocessing coatings to meet the needs of a wide spectrum of uses and applications. Through computational simulations involving the finite element method and accompanying experiments, we develop quantitative insights and a general framework for creating complex shapes in eco-friendly natural materials with potential sustainable applications for scalable manufacturing.

A lignin-based PU coating was prepared for paper-based green packaging. Two representative diisocyanate were used to prepare the coatings. Due to the rigid aromatic, the physical properties of the TDI system reached the maximum below the lignin content of 40%. The HDI that contains flexible aliphatic chains alleviated the brittleness of coating, and it showed physical advantages when the lignin content was more than 50%. Owing to the high lignin content, the coating presented enhanced thermal stability. After coated with the lignin-based PU coatings, the dry tensile strength of coated paper was improved by 126%. Amazingly, the wet strength was increased from 0.31 to 12.6 MPa with an improvement nearly 40 times. Based on the coordination of lignin, Ag+ was introduced into the PU matrix, which imparted the coating with excellent antibacterial ability. The colony forming units of E. coli and S. aureus were both less than 1. However, no inhibition halo was observed, which indicated that the Ag was firmly anchored on the coating and the antibacterial ability is only available when the bacterial contact the coating surface. The lignin-based PU coating with favorable sustainability and properties shows great potential in paper-based green packaging fields.

Paper has become the basic elixir in everyone's activities and usage of paper has increased day by day, the waste generated by paper is also enormous. The primary source of paper is wood (tree) yet, waste paper is environmentally good and biodegradable; however, it is the primary source of deforestation. Current research aims to find an alternate way to recycle paper in the biological approach. Hence in our work, twelve cellulose-producing bacteria were isolated, out of which one bacterial strain proved to be the best. Cellulase enzyme was extracted and purified, and used for enzymatic de-inking of photocopy papers. The optimal conditions for cellulase synthesis were at 60 °C, glucose as the only carbon source, and potassium nitrate as the nitrogen source. The enzyme demonstrated excellent de-inking at a lower pulp consistency of 3% with a 20% enzyme dose. The cellulose and hemicellulose levels decreased, which can be attributed to fiber breaking. Further, the changes in the functional groups identified by Fourier-transform infrared spectroscopy analysis and the changes in the surface morphology of the pulp fibers were obtained using scanning electron microscope analysis.

We present a study of the electrical, structural and chemical properties of Ti contacts on atomic layer deposited α-Ga2O3 film. Ti forms an ohmic contact with α-Ga2O3. The contact performance is highly dependent on the post-evaporation annealing temperature, where an improved conductivity is obtained when annealing at 450 °C, and a strong degradation when annealing at higher temperatures. Structural and chemical characterisation by transmission electron microscopy techniques reveal that the electrical improvement or degradation of the contact upon annealing can be attributed to oxidation of the Ti metallic layer by the Ga2O3 film in combination with the possibility for Ti diffusion into the Au layer. The results highlight that the grain boundaries and inclusions in the Ga2O3 film provide fast diffusion pathways for this reaction, leaving the α-Ga2O3 crystallites relatively unaffected—this result differs from previous reports conducted on β-Ga2O3. This study underlines the necessity for a phase-specific and growth method-specific study of contacts on Ga2O3 devices.

The pulp and paper industry consumes a huge amount of water and releases more polluted and colored wastewater every year. Many conventional techniques are used in the treatment of paper industry wastewater. However, for color removal from paper mill effluent, there is no proven method so far, on an industrial scale. Due to high energy input and high cost, there is an urgent need to find out a new technique that must be sustainable, economical, and environment friendly. Various methods have been investigated on bench scale and pilot scale also but no proven method for color removal on an industrial scale. The paper provides an overview of the color removal techniques from different sources of pulp and paper mill wastewater discharged by various industries. The review described various components involved in various processes for color removal from paper mill waste water. The present works focus on processes like chemical, chemical/physical, biological, physicochemical, and electrochemical applied in color removal from paper mill wastewater. The present review gives key information on the effectiveness, use, betterment, and limitations of numerous methods of treatment targeted at color removal from paper mill wastewater using various techniques still under evolution.

Replacing synthetic polymers with renewable alternatives is a critical challenge for the packaging industry. This research investigated the use of leaf-based proteins as a sustainable co-binder in the coating formulations for paper-based packaging and other applications. Protein isolates from tobacco leaf and alfalfa concentrates were characterized using the Pierce protein assay, Kjeldahl nitrogen, and gel electrophoresis. The proteins were tested as co-binders in a typical latex-based paper coating formulation. The rheology and water retention properties of the wet coating and the surface, optical, structural, and strength properties of coated papers were measured. The coating performance was affected by the purity, solubility, and molecular weight of the tobacco protein and exhibited a shear-thinning behavior with lower water retention than soy protein. Analysis by scanning electron microscopy and time of flight secondary ion mass spectroscopy on the dried coating layer containing tobacco protein showed enhanced porosity (advantageous for package glueability) relative to the control latex coating. The tobacco protein offers adequate coverage and coating pigment distribution, indicating that this protein can be a suitable option in coatings for packaging applications.

Removing benzene from indoor space plays an important role in indoor air purification. A novel filter with vegetal fiber paper (VFP) as matrix hosting silica gel is proposed in this paper for benzene removal. In order to investigate the feasibility and performance of this idea, firstly, three pieces of VFP samples impregnated with different amounts of silica gel are fabricated and their benzene adsorption quantities are tested. The results show that three times is recommended as the optimal number for impregnating. The VFP sample impregnated with silica gel after the third impregnating exhibits commendable coating stability and good benzene adsorption performance. Additionally, at low relative pressure (Pb /Ps ≤ 0.05), the experimental data of benzene adsorption isotherms fit well with the Langmuir model with R2 greater than 0.97. Then, two actual filters made of VFP impregnated with silica gel after the third impregnating were fabricated. It is found that the pressure drop of the actual filter is only 1200 Pa/m when the air velocity is 2 m/s. Besides, the one-pass efficiency of the filter can reach to 19.44%. It is expected that the silica gel coated on the filter can be modified to improve the purification performance of the filter.

Anionic pectic substances in whitewater from papermaking are detrimental to machine operation and product quality. Pectinase was immobilized on pulp fiber using cationic polyacrylamide with layer-by-layer method to obtain bound enzyme with tunable activity and good performance for wastewater treatment. It was revealed that high charge density and low molecular weight for cationic polyacrylamide were advantageous for enzymatic activity. During the layer-by-layer adsorption process, the enzymatic activity of the immobilized enzyme increased nearly linearly with the layer number from 983 to 3074 U/g until the fourth layer. The stability of the four-layer immobilized enzyme was improved. The multilayer immobilized enzyme exhibited good reusability and storage stability compared with monolayer enzyme. At dosage of 10 U/mL, the cationic demand of the whitewater samples was reduced by 15% using four-layer immobilized enzyme. The results indicated a potential route to prepare immobilized enzyme with good performance for wastewater treatment in papermaking industry.

Solar-reflective thermal insulating coating (SRC) has received great attention because of its desired heat reflective properties and water repellency, which may impart high-value to cellulosic paper via industrially well-established surface coating process. However, the feasibility and possibility of surface application of SRC to cellulosic paper have not been explored. Herein, in the present work, SRC was designed/developed and subsequently used in the surface application to cellulosic paper. Effect of feeding level of titanium dioxide nanoparticles (nano-TiO2) on rheological behavior of the coating, as well as heat-reflective properties, water repellency and mechanical properties of the surface-coated paper was studied. Results showed that the as-obtained coating samples exhibited a notable shear-thinning behavior and displayed strong dependence of rheological behavior on nano-TiO2 amount. Furthermore, the increased nano-TiO2 amount appeared to induce the improved hemispherical emittance of coated paper. The coating weight was also found to exert a positive effect on the hemispherical emittance of coated paper. In addition, it was confirmed that the nano-TiO2 addition played an important role in improving the water repellency and mechanical properties of coated paper.

WOS: 000462022300057 PubMed: 30474775 A newly identified ligninolytic Rhodococcus strain (Rhodococcus sp. T1) was isolated from forestry wastes (Trabzon/Turkey). The DyP type peroxidase of Rhodococcus sp. T1 (DyPT1) was cloned, characterized and paper treated for industrial applications. Molecular weight of the protein was about 38kDa. The kinetic parameters were 0.94mM and 1417.53 mu mol/min/mg for Km and Vmax, respectively. The enzyme was active at the temperature range of 25-65 degrees C and optimum temperature was 35 degrees C, enzyme was stable up to 6 days at room temperature. Optimum pH of the DyPT1 was 4.0 and it was stable between pH 4.0-6.0 up to 8 days at room temperature. Effects of some metal ions, Hemin, and some chemical agents on DyPT1 were determined. Hemin has implemented protective effects on the stability and the activity of the enzyme in long time periods when added into growing medium. DyPT1 was applied to eucalyptus kraft pulp for analyzing the bleaching efficiency, physical and optical tests of the manufuctared paper were carried out. Application of lignin peroxidase to kraft pulp caused a decrease of 5.2 units for kappa number and an increase from 52.05 to 64.18% in the delignification rate. Karadeniz Technical University Research Foundation [FBA-2015-5182] This study was financially supported by Karadeniz Technical University Research Foundation (Project No: FBA-2015-5182).

Production of laccase from Ganoderma lucidum RCK 2011 under solid-state fermentation (SSF) conditions was optimized using response surface methodology, resulting in an approximate eightfold increase compared to that in the unoptimized media. Further, the enzyme produced under SSF as whole fermented substrate (in situ SSF laccase) was found to be more stable than the in vitro enzyme (harvested by downstreaming processing of fermented wheat bran). Interestingly, the biobleaching potentials of both in situ and in vitro SSF laccases were comparable, saving 25% chlorine dioxide for achieving similar pulp brightness as obtained in the pulp treated chemically. The reduction in the demand of chlorine dioxide in the pulp bleaching sequence subsequently decreased the levels of adsorbable organic halogen (AOX) in the resulting effluents of the process by 20% compared to the effluents obtained from chemical bleaching sequence. Therefore, direct application of in situ SSF laccase in pulp biobleaching will be environmentally friendly as well as economical and viable for implementation in paper mills.

Driven by the environmental benefits that bio-bleaching could bring, the interest in xylanase has received enormous attention and hence, the search of xylanase with properties like no cellulase activity, function at elevated temperatures and pH continues. The present study reports the production of extracellular xylanase from Aspergillus nidulans using waste agro-residues as substrate. The optimum temperature (60 °C) and pH (9.0), classified the xylanase as thermo and alkali tolerant. The addition of salt of Mn2+ increased the xylanase activity to almost double; however, these ions were unable to protect the enzyme from thermal inactivation. The FTIR spectra of bamboo pulp treated with this xylanase, revealed reduction in lignin as evident from reduced peak intensity coupled with the reduction in kappa number. The SEM image of enzyme treated pulp, exhibited dissociation in fibers exposing the internal structure with slight roughness. Swelling was also observed there by increasing its thickness which eventually helped in improving its physical properties. The bleaching efficacy of indigenous xylanase as indicated in this study, has established its competence as a promising candidate for pre-treating the bamboo pulp.

The article presents the research results of the oxidation of watered toxic waste from the pulp and paper industry (sludge-lignin, the empirical formula of organic matter CH1.51N0.05S0.03Cl0.01O0.54) in supercritical water-oxygen (SCW/O2) fluid. The experiments were carried out using a flow tube reactor at a pressure of 25 MPa, temperature gradient along its vertical axis (from top to bottom: 390–600 °C), sludge-lignin flow rate of 9.5–14.5 g/min, oxygen ratio OR = 0.73–2.52, using NaOH (1.6 wt%) as a catalyst. Employing gas chromatography – mass spectrometry, polychlorophenols were identified in the composition of sludge-lignin, in which 2,4,6-trichlorophenol was the main component. The total yield of extracted phenols and chlorophenols per sludge-lignin organic matter was 20.82 and 2.88 μg/g, respectively. It is revealed that the conversion rate of sludge-lignin in SCW/O2 fluid is limited by heterogeneous oxidation of the carbonized residue, and is determined by the O2 content in the reaction mixture. At OR ≥ 1.16, only CO2, CO, N2, and N2O were detected in the volatile oxidation products. An increase in OR from 0.73 to 2.52 leads to a decrease in the total content of phenols (from 45540.1 to 129.3 μg/dm3) and chlorophenols (from 51.4 to 2.2 μg/dm3) in the water collected at the reactor outlet. It is shown that 2,6-dichlorophenol and 2-chlorophenol are the most resistant to oxidation. From the analysis of the initial sludge-lignin and mineral residues, it follows that the bulk of the chlorine contained in its organic matter is converted into NaCl in the course of oxidation.

The progress of bio-based fluorescent smart materials and their multifunctional applications have attained increasing interest in the recent decades. Cellulose is among the cheapest and widespread raw material on earth which can be modified into diverse useful materials. This review summarizes the chemical modification of cellulose into smart fluorescent materials. This further highlights on the fabrication of the prepared fluorescent materials into films, fibers, paper strips, carbon dots, hydrogels and solutions which are applied for the sensing of toxic metals and anions, pH, bioimaging, common organic solvents, aliphatic and aromatic amines, nitroaromatics, fluorescent printing, coating, and anti-counterfeiting applications. Finally, the discussion about the upcoming investigations, challenges, and options open for the cellulose-based luminescence sensors are communicated. We believe that this review will appeal more and more attention and curiosity for the chemists, biochemists, and chemical engineers working with the synthesis of cellulose-based fluorescent materials for widespread applications.

Funding Information: The authors are grateful with Arauco Bioforest S.A. for giving the right to use the presented results. Publisher Copyright: © 2021 The Authors A pulsed electrodialysis reversal (pEDR) process is proposed to desalinate spent water after particle removal, biological and chemical coagulation, which are commonly used as a sequence in Kraft pulp mills. pEDR affords closed-loop processing, reducing the need for freshwater intake while maintaining the quality of recirculating process streams. Compared with conventional electrodialysis, pEDR minimizes production losses (from 5 % to 0.6 %), extending the time for hydraulic reversal (from 15 min to at least 2 h). Simultaneously, the conductivity of the effluent is significantly reduced, from 2100 to 200 μS/cm, reaching a quality similar to the feed water. The operation cost (0.38 US$/m3) is factored in the techno-economic viability of the process water recirculation, which is also demonstrated for its scalability. Additionally, WinGEMS simulation highlights the benefits of installing a pEDR unit, positively impacting mill water under different recirculation rates. Overall, we show remarkable gains in water economy, operation (maintenance and fouling), and quality, which are critical factors in achieving resource sufficiency.

The bleach plant of a pulp and paper (P&P) mill presents a major source of wastewater containing toxic organic matter characterized as chemical oxygen demand (COD). Due to their high oxidizing power, oxidoreductases hold promise to be a key solution for the removal of dissolved organic material. Here, four oxidoreductases from different enzyme families were selected to treat bleach plant effluents. Haloperoxidase treatment of the final effluent resulted in the highest levels of decolorization (71%) and reduction of aromatic compounds (36%). Using single compound analysis, 27 low molecular weight compounds were found to be persistent throughout the wastewater treatment process and, therefore, classified as hard COD. The tested enzymes efficiently removed several of the identified COD compounds. Hence, this study suggests that the application of oxidoreductases will serve as an environmental-friendly solution for reducing waste from P&P production.

Paper based sensor is the new technology to fabricate a simple, portable, and low cost device that exhibits the comparable properties and functions with those fabricated using complex fabrication process. Paper based sensor is usually applied in environmental monitoring, health diagnostics, and food quality control. This research is focusing on the paper based sensor that will contribute to the development of Ultraviolet (UV) sensor. The fabrication of the sensor was done by using different grade of pencil, namely 6B and 2B on different type of paper. The different grade of pencil corresponds to different percentage of graphite and clay. As for the type of paper, A4 printing paper and Whatman filter paper were used. UV sensing operation was analyzed from the measurement of current-voltage (I-V) characteristics under the exposure of UV light. Zinc oxide (ZnO) was coated on the sensor to facilitate the detection in the presence of UV. The sample fabricated using 6B pencil grade on A4 printing paper and with ZnO coating showed a better UV sensing performance compared to other samples. This is due to the high conduction of 6B pencil grade and smooth surface of A4 printing paper. The ZnO coating increased the sensor sensitivity and response towards the UV light. These findings provide valuable information which can be used in fabricating a low-cost and simple UV paper sensor.

The European Union-funded Advanced Superconducting Motor Experimental Demonstrator (ASuMED) project started in May 2017 with the purpose of demonstrating the benefits of a new, fully superconducting motor for reaching the targets established by the Flightpath 2050 plan. The project aims at a motor power density of 20kW kg−1 using a high-temperature superconducting (HTS) stator. The rotor will use HTS stacks operating like permanent magnets. A highly efficient cryostat for the motor combined with an integrated cryogenic cooling system and associated power converter will be used. This article provides a general overview of the prototype that is currently being assembled and that will be tested soon.

In the present work, a facile and green synthesis approach for the production of monodispersed, small-sized (2.9 ± 0.7 nm) and stable silver nanoparticles (AgNPs) using soluble soybean polysaccharide (SSPS) was reported. SSPS was used as the reducing and stabilizing agent. The obtained SSPS-stabilized AgNPs (SA) were characterized by UV–vis absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy and transmission electron microscopy. The antimicrobial activity of the SA colloidal dispersion (SACD) was evaluated based on the growth kinetics of bacteria E. coli and S. aureus. Afterwards, the colloidal dispersion was applied as a coating material to Kraft paper. The SACD-coated Kraft paper exhibited excellent antimicrobial activity against above bacteria strains and P. aeruginosa. The effects of SACD coating on surface wettability, barrier property and microstructure of the Kraft paper were also studied. The results suggested that the SSPS-stabilized AgNPs have great potential in antibacterial applications.

Bio-bleaching effect on bagasse pulp using xylano-pectinolytic enzymes produced by a bacterial species was studied in order to evaluate the potential of these enzymes in paper industry. In this study, action of enzymes was maximum with xylanase/pectinase dose 7/1.75 IU/g, pulp consistency 1:12.5 g/L, pH 8.5, temperature 50° C and 180 min of treatment time. Under the optimized bio-bleaching conditions, removal of reducing sugars (6.15±0.05 mg/L), brightness (16.08%), whiteness (25.54%) and release of chromophores (hydrophobic and phenolic compounds and lignin impurities) were maximum, along with decrease in kappa number (26.28%), and yellowness (27.88%) values were obtained. Improvement in the various physical properties like breaking length (10.28%), burst index (29.55%), tear index (5.02%), double fold (14.89%), Gurley porosity (15%) and viscosity (8.6%), along with the reduction of chlorine dioxide dose by 27%, was also observed. There is also reduction in COD and BOD values of bio-bleached effluents by 27.62% and 20.52%, respectively. This is the first report on bio-bleaching of bagasse pulp using xylano-pectinolytic enzymes.

Bioprocessing of pulp requires lignolytic as well as hemicellulolytic enzymes. The present study is the first report of a cocktail of laccase (L), xylanase (X), and mannanase (M), from a single bacterium for pulp biobleaching. A novel strain Bacillus tequilensis LXM 55 produced thermo-alkali stable L + X + M. On optimization higher enzyme yield (IUml−1/fold increase) of laccase (396.35/24.16), xylanase (212.95/81.90) and mannanase (153.33/102.90) were achieved in the cocktail. Treatment of pulp with cocktail of enzymes led to 49.35% reduction in kappa number and considerable enhancement in the brightness (11.59%), whiteness (4.11%), and other pulp properties. Most importantly, no mediator system was required for the application of laccase. 40% less chlorine consumption was required to obtain the paper of the same quality as that of pulp treated without enzyme but with 100% chlorine. Therefore, this cocktail of enzymes is highly suitable for pulp biobleaching in the paper mill.

This research was carried out with an objective to examine the efficacy of ultrafiltered xylano-pectinolytic enzymes in pulping of sugarcane bagasse. Maximum biopulping was achieved with enzyme dose of xylanase (175 IU / g bagasse) and pectinase (75 IU / g bagasse) at treatment period of 180 min. The temperature, pH, and bagasse to liquid ratio for biopulping experiments were kept constant at 55o C, 8.5, and 1:10 (g/ml), respectively. The ultrafiltered biopulping improved chemical pulping, resulted in 25.11%, 9.17% increase in brightness, unscreened pulp production and 11.81, 59.50, and 49.14% decrease in total solids, rejections. and kappa number, respectively. The bagasse biopulping also resulted in 15% decrease of alkali load to attain similar kappa number and optical properties as obtained under 100% alkali dosage. Ultrafiltered biopulped-unbleached samples showed significant increase in breaking length (13.55%), burst index (40.21%), tear index (19.04%), double fold (42.5%), Gurley porosity (28.21%) and viscosity (13.37%) in comparison with non-enzymatically treated control pulp samples. In comparison with non biotreated-bleached pulp samples, ultrafiltered biopulped-bleached samples also resulted in higher burst index (56.80%), breaking length (17.38%), double fold (39.58%), tear index (3.38%), viscosity (30.68%), and Gurley porosity (52.50%). This environmentally sustainable ultrafiltered biopulping approach for sugarcane bagasse has the potential to decrease the demand of chemicals, ultimately pollution along with enhance the quality of paper.

In this study, suitability of xylano-pectinolytic enzymes in pulping of wheat straw has been explored. The suitable biopulping conditions were optimized, with xylanase dose of 400 and pectinase dose of 120 IU/g wheat straw, 1:10 (g/ml) material to liquid ratio, 55 °C temperature, 3 h treatment time, 0.75% Tween 80 and pH 8.5. Enzymatic pretreatment efficiently increased the pulpability of wheat straw, generated pulp with higher yield, lower kappa number (15.67%) and rejections (59.65%) in comparison with chemical pulp. The brightness of pretreated wheat straw pulp with enzyme was 16.04% higher than that of the non-enzyme treated wheat straw pulp. The biopulping resulted in 12% reduction of pulping chemicals along with more residual alkali content, in order to achieve similar optical and chemical properties as obtained by 100% chemically treated pulp. Physical properties of pulp also improved after enzymatic pretreatment, increasing burst index (26.50%), tear index (18.22%) and breaking length (5.56%). The enzyme plus chemical (88% pulping chemicals) treated pulp showed improvement in brightness and whiteness, with reduction in yellowness at all bleaching stages. In comparison with chemically bleached pulp, biopulp with reduced alkali dose (88%) had higher breaking length (6.63%), double fold number (51.28%), tear index (2.83%), burst index (24.31%), along with increased viscosity (6.12%) and Gurley porosity (27.50%). These results clearly suggest that biopulping of wheat straw with xylano-pectinolytic enzymes can reduce chemical loading during soda-anthraquinone pulping and also improve the quality of paper. This is the first report demonstrating the biopulping of wheat straw using crude xylano-pectinolytic enzymes.

A paper-based platform was developed and tested for studies on basic cell culture, material biocompatibility, and activity of pharmaceuticals in order to provide a reliable, robust and low-cost cell study platform. It is based upon a paper or paperboard support, with a nanostructured latex coating to provide an enhanced cell growth and sufficient barrier properties. Wetting is limited to regions of interest using a flexographically printed hydrophobic polydimethylsiloxane layer with circular non-print areas. The nanostructured coating can be substituted for another coating of interest, or the regions of interest functionalized with a material to be studied. The platform is fully up-scalable, being produced with roll-to-roll rod coating, flexographic and inkjet printing methods. Results show that the platform efficiency is comparable to multi-well plates in colorimetric assays in three separate studies: a cell culture study, a biocompatibility study, and a drug screening study. The color intensity is quantified by using a common office scanner or an imaging device and the data is analyzed by a custom computer software without the need for expensive screening or analysis equipment.

Waste paper is a major contributor to municipal and industrial waste, and its recycle and reuse are a current challenge. The aim of this research is to convert waste paper into value-added cellulose films through rapid dissolution in pre-cooled H2SO4 aqueous solution. Two types of waste paper, office paper and cardboard, could be dissolved within 210 s. The regenerated office paper films were transparent, and exhibited excellent mechanical properties (tensile strength: 77.55 ± 6.52 MPa, elongation at break: 2.67 ± 0.30 %, and Young’s modulus: 5451.67 ± 705.23 MPa), which were comparable to those of cellulose films prepared from spruce pulp in the same solvent. The mixed paper films showed a dramatically reduced UV transmittance due to the existence of lignin. Moreover, the regenerated films were a promising matrix to load antimicrobial compounds, and thus inhibited the growth of pathogenic bacteria. Therefore, this work provides a convenient way to directly convert waste paper into biodegradable antimicrobial packaging materials.

A functional biopolymer-coated paper was prepared by coating a ternary blend of the alginate, carboxymethyl cellulose, and carrageenan with grapefruit seed extract (GSE) for the substitute use of synthetic polymer-coated paper. The microstructure of the surface and cross-section of the coated paper analyzed by field emission scanning electron microscope (FE-SEM) indicated that the biopolymer was compatible with the base paper and filled the pores of the porous fiber to make a smooth-surfaced coating paper. The properties of the biopolymer-coated paper, such as water and oil resistance, water vapor barrier, surface hydrophobicity, and mechanical properties, increased significantly compared with not only the base paper but also commercially used PE-coated paper. The blended biopolymer coating material exhibited strong antibacterial activity against food-borne pathogenic bacteria, Listeria monocytogenes and Escherichia coli, which were destroyed completely within 3 and 9 h, respectively. The packaging test for a minced fish cake packed with the biopolymer-coated paper showed the complete destruction of surface inoculated bacteria in 6–9 days. The biopolymer-coated paper showed a high potential for disposable food packaging applications to increase the shelf-life of packaged food.

Lipase enzyme has a critical role in deinking process along with other lignocellulosic enzymes. In this paper, we try to demonstrate the role of lipase in the enzyme cocktail used for enzymatic deinking. For this, we identified a potential lipolytic bacterium, Pseudomonas mendocina ED9 isolated from elephant dung with a molecular weight of 35 kDa. During the Box-Benhken model optimization, a maximum lipase activity of 105.12 U/g, which was 12.36-fold higher than the initial enzyme activity and 1.3-fold higher than the activity obtained during the Plackett Burman design, was achieved. A maximum lipase activity of 105.12 U/g was obtained after optimization. Ammonium sulphate (60%) precipitation resulted in a specific activity of 68.19 U/mg with a 1.4-fold purification and yield of 64%. Lipase from P. mendocina ED9 exhibited a Km of 0.5306 mM and Vmax of 25.0237 μmol/min/mg. A Δ brightness of approximately 14.5% were achieved during the enzymatic deinking using cocktail comprised of cellulase, xylanase and lipase. This reports the significant role and efficacy of lipase in enzyme cocktails for deinking applications. This formulation will reduce the pollution and environmental toxicity of conventional chemical deinking.