Material Separation from Polyester/Cotton Blended Fabrics Using Hydrothermal Treatment.

The production of textile products is increasing annually, and most of them are disposed of after use without recycling. One of the reasons for the low recycling percentage of discarded textile products is the difficulty of recycling as a single material as these products are produced from a combination of two or more materials. Therefore, a technology to separate materials is necessary to improve the recycling percentage of textile products and to build a sustainable recycling industry. The aim of this study was to separate the most common combination of materials, such as cotton/polyester, in an environmentally friendly technique using hydrothermal treatment with only water. Herein, the optimal treatment conditions for blended fabrics in a high-pressure reactor were studied. Moreover, cotton could be separated by treating the fabrics at 220 to 230 °C for 10 min while maintaining the shape of the fabrics. Additionally, polyester showed a melting point, confirming that polyester could be separated without decomposition into monomers, unlike common chemical recycling. The strength of the separated cotton and the molecular weight of the polyester were evaluated, and a kinetic analysis of the changes due to the treatment was conducted. The activation energy obtained from the Arrhenius plot was 111.8 kJ/mol for PET, which was smaller than 142.6 kJ/mol for cotton. This indicates that the decrease in the molecular weight of PET is more likely to occur than the change in the strength of cotton, suggesting the possibility of separating the materials from the kinetic analysis.

Fast and selective production of quercetin and saccharides from rutin using microwave-assisted hydrothermal treatment in the presence of graphene oxide.

Rutin is a flavonoid glycoside, well-known for its antioxidant, anticarcinogenic, and cardioprotective properties. However, it exhibits lower bio absorptivity and bioactivity than its aglycon form, quercetin. Although liquid acid catalysts are conventionally utilized to obtain quercetin via rutin hydrolysis, the neutralization procedure is a major disadvantage owing to the added cost. In this study, graphene oxide (GO) was used as an alternative catalyst under microwave (MW) irradiation, owing to its easy separation from the reaction solution and high MW absorptivity, resulting in improved thermal efficiency. Two types of GOs were prepared (GO-HU using Hummer's method and GO-TO using Tour's method), and their catalytic performance for rutin hydrolysis was evaluated and compared. The highest rutin conversion (98.8 %) and quercetin yield (81.9 %) were obtained at 180 °C when the reaction was conducted for 15 min using 3 mg of GO-TO and 2400 ppm of initial rutin concentration in 50 mL of water.

Nano-pulsed discharge plasma-induced abiotic oligopeptide formation from diketopiperazine.

Conventional oligopeptide synthesis techniques involve environmentally harmful procedures and materials. In addition, the efficient accumulation of oligopeptides under Hadean Earth environments regarding the origin of life remains still unclear. In these processes, the formation of diketopiperazine is a big issue due to the strong inhibition for further elongation beyond dipeptides. Hydrothermal media enables environmentally friendly oligopeptide synthesis. However, hydrothermal oligopeptide synthesis produces large amounts of diketopiperazine (DKP), due to its thermodynamic stability. DKP inhibits dipeptide elongation and also constitutes an inhibitory pathway in conventional oligopeptide synthesis. Here, we show an efficient pathway for oligopeptide formation using a specially designed experimental setup to run both thermal and non-thermal discharge plasma, generated by nano-pulsed electric discharge with 16-23 kV voltage and 300-430 A current within ca. 500 ns. DKP (14%) was converted to dipeptides and higher oligopeptides in an aqueous solution containing alanine-DKP at pH 4.5, after 20 min of 50 pps thermal plasma irradiation. This is the first study to report efficient oligopeptide synthesis in aqueous medium using nano-pulsed plasma (with thermal plasma being more efficient than non-thermal plasma) via DKP ring-opening. This unexpected finding is implicative to evaluate the pathway how the oligopeptides could have accumulated in the primitive Earth with high-energy plasma sources such as thunder as well as to facilitate the green synthesis of oligopeptides.

The O'Leary-Sant Interstitial Cystitis Symptom Index is a clinically useful indicator of treatment outcome in patients with interstitial cystitis/bladder pain syndrome with Hunner lesions: A post hoc analysis of the Japanese phase III trial of KRP-116D, 50% dimethyl sulfoxide solution.

OBJECTIVES: To evaluate the efficacy of intravesical KRP-116D, 50% dimethyl sulfoxide solution, in interstitial cystitis/bladder pain syndrome patients with Hunner lesions (Hunner-type interstitial cystitis), and to evaluate the correlations between efficacy variables and global response assessment to determine what constitutes a minimal clinically important change. METHODS: We performed a post hoc analysis of the Japanese phase III trial of KRP-116D. Changes at Week 12 from baseline in objective and subjective outcomes were compared between the KRP-116D and placebo groups in Hunner-type interstitial cystitis or non-Hunner-type interstitial cystitis patients. Correlations between efficacy variables at Week 12 and global response assessment were analyzed. Area under the receiver operating characteristic curve and the cut-off value of efficacy valuables were calculated to determine clinically meaningful changes. RESULTS: The effectiveness of intravesical treatment with KRP-116D was demonstrated in Hunner-type interstitial cystitis, but not in non-Hunner-type interstitial cystitis patients. Global response assessment was closely correlated with subjective outcomes including O'Leary-Sant Interstitial Cystitis Symptom Index, O'Leary-Sant Interstitial Cystitis Problem Index, and a numeric rating scale for bladder pain, but was less correlated with voiding variables including micturition frequency, voided volume, and maximum voided volume. In the receiver operating characteristic curve analyses, the cut-off value for the O'Leary-Sant Interstitial Cystitis Symptom Index was -5 (sensitivity 81.3%, specificity 83.3%). CONCLUSIONS: Clinical benefit of intravesical KRP-116D in Hunner-type interstitial cystitis patients was confirmed in this post hoc analysis. A five-point reduction in O'Leary-Sant Interstitial Cystitis Symptom Index is a clinically meaningful indicator for assessing patient satisfaction with KRP-116D treatment in patients with Hunner-type interstitial cystitis.

Biogasoline production from linoleic acid via catalytic cracking over nickel and copper-doped ZSM-5 catalysts.

Catalytic cracking of vegetable oil mainly processed over zeolites, and among all the zeolites particularly HZMS-5 has been investigated on wide range for renewable and clean gasoline production from various plant oils. Despite the fact that HZSM-5 offers a higher conversion degree and boost aromatics yield, the isomerate yield reduces due to high cracking activity and shape selectivity of HZSM-5. Hence, to overcome these problems, in this study the transition metals, such as nickel and copper doped over HZSM-5 were tested for its efficiencies to improve the isoparaffin compounds. The catalysts were screened with linoleic acid in a catalytic cracking reaction conducted at 450 ᵒC for 90 min in an atmospheric condition in batch reactor. Then, the gasoline composition of the organic liquid product (OLP) was analysed in terms of paraffin, isoparaffin, olefin, naphthenes and aromatics (PIONA). The results showed that Cu/ZSM-5 produced the highest liquid yield of 79.1%, at the same time reduced the production of gas and coke to 18.8% and 0.7%. Furthermore, the desired isoparaffin composition in biogasoline increased from 1.6% to 6.8% and at the same time reduced the oxygenated and aromatic compounds to 15.4% and 59.7%, respectively. The linoleic acid as model compound of rubber seed oil, in the catalytic cracking reaction provides a clearer understanding of the process. Besides, the water gas shift (WGS) reaction in catalytic cracking reaction provides insitu hydrogen production to saturate the branched olefin into the desired isoparaffin and the aromatics into naphthenes.

Carbocatalysed hydrolytic cleaving of the glycosidic bond in fucoidan under microwave irradiation.

Biomass valorization involves breaking down naturally occurring long chain polysaccharides into their constituent monomers. The polysaccharide chain consists of monomers adjoined via C (carbon)-O (oxygen) glycosidic linkages that are typically cleaved via hydrolytic scission. In this study, we aimed to recover fucose from the polysaccharide fucoidan, which can be extracted from seaweed biomass. We investigated the depolymerisation behavior of fucoidan sourced from two different species of seaweeds, namely Undaria pinnatifida (F-UP) and Fucus vesiculosus (F-FV). Catalytic depolymerisation experiments were performed using four different carbon-based catalysts - graphene, multiwalled carbon nanotubes (MWCNT), graphene oxide (GO), and reduced graphene oxide (rGO) - under microwave (MW) irradiation. Our results showed that the depolymerisation of fucoidan was best achieved using GO, which was attributed to the abundance of oxygen functionalities on its surface. Furthermore, based on gel permeation chromatography analyses, the depolymerisation of fucoidan was found to follow a two-step process: (1) random scission leading to the production of short-chain oligosaccharides and (2) acid-catalysed hydrolysis of the oligosaccharides to fucose. Because of the longer chain length of F-UP (61 kDa), the highest fucose yield of 17.4% using this species was obtained at a higher temperature of 120 °C in a closed vessel. Meanwhile, in the case of F-FV (1.1 kDa), the highest yield of 54.0% was obtained under reflux conditions at a lower temperature of 104 °C. Our mechanistic study based on semi-empirical quantum calculations also revealed that the recovery of fucose from F-FV is more energetically favoured than from F-UP as a result of their structural differences.

Production of gasoline range hydrocarbons from catalytic cracking of linoleic acid over various acidic zeolite catalysts.

Employment of edible oils as alternative green fuel for vehicles had raised debates on the sustainability of food supply especially in the third-world countries. The non-edible oil obtained from the abundantly available rubber seeds could mitigate this issue and at the same time reduce the environmental impact. Therefore, this paper investigates the catalytic cracking reaction of a model compound named linoleic acid that is enormously present in the rubber seed oil. Batch-scale experiments were conducted using 8.8 mL Inconel batch reactor having a cyclic horizontal swing span of 2 cm with a frequency of 60 cycles per minute at 450 °C under atmospheric condition for 90 min. The performance of HZSM-5, HBeta, HFerrierite, HMordenite and HY catalysts was tested for their efficiency in favouring gasoline range hydrocarbons. The compounds present in the organic liquid product were then analysed using GC-MS and classified based on PIONA which stands for paraffin, isoparaffin, olefin, naphthenes and aromatics respectively. The results obtained show that HZSM-5 catalyst favoured gasoline range hydrocarbons that were rich in aromatics compounds and promoted the production of desired isoparaffin. It also gave a higher cracking activity; however, large gaseous as by-products were produced at the same time.

Sustainable green pretreatment approach to biomass-to-energy conversion using natural hydro-low-transition-temperature mixtures.

Natural hydro-low-transition-temperature mixtures (NH-LTTMs) tend to be the most favorable next-generation green solvents for biomass pretreatment, as they are cheap and environmental friendly. The amount of water bound into the NH-LTTMs greatly affected their thermal stability, whereby the highest thermal stability was observed with the water content of 7.6 wt%. It is worth noting that, the highest molar transition energy of NH-LTTMs (47.57 kcal mol-1), which indicated the highest solubility, was optimized with the molar ratio of hydrogen bond donor (HBD)-hydrogen bond acceptor (HBA)-water (2:4:3) at a temperature of 60 °C. Hydrogen bonding networks of the NH-LTTMs, which led to the dissolution of biomass, were confirmed by the alteration in the peaks of the involved bonds and resonance signal to lower field through FTIR and 1H NMR spectra, respectively. The components evidenced in high-resolution mass spectra of extracted lignin showed its high potential to be valorized into useful fuels and chemicals.

Thermogravimetric analysis and kinetic modeling of low-transition-temperature mixtures pretreated oil palm empty fruit bunch for possible maximum yield of pyrolysis oil.

The impacts of low-transition-temperature mixtures (LTTMs) pretreatment on thermal decomposition and kinetics of empty fruit bunch (EFB) were investigated by thermogravimetric analysis. EFB was pretreated with the LTTMs under different duration of pretreatment which enabled various degrees of alteration to their structure. The TG-DTG curves showed that LTTMs pretreatment on EFB shifted the temperature and rate of decomposition to higher values. The EFB pretreated with sucrose and choline chloride-based LTTMs had attained the highest mass loss of volatile matter (78.69% and 75.71%) after 18 h of pretreatment. For monosodium glutamate-based LTTMs, the 24 h pretreated EFB had achieved the maximum mass loss (76.1%). Based on the Coats-Redfern integral method, the LTTMs pretreatment led to an increase in activation energy of the thermal decomposition of EFB from 80.00 to 82.82-94.80 kJ/mol. The activation energy was mainly affected by the demineralization and alteration in cellulose crystallinity after LTTMs pretreatment.

Choline chloride (ChCl) and monosodium glutamate (MSG)-based green solvents from optimized cactus malic acid for biomass delignification.

This work aimed to develop an efficient microwave-hydrothermal (MH) extraction of malic acid from abundant natural cactus as hydrogen bond donor (HBD) whereby the concentration was optimized using response surface methodology. The ideal process conditions were found to be at a solvent-to-feed ratio of 0.008, 120°C and 20min with 1.0g of oxidant, H2O2. Next generation environment-friendly solvents, low transition temperature mixtures (LTTMs) were synthesized from cactus malic acid with choline chloride (ChCl) and monosodium glutamate (MSG) as hydrogen bond acceptors (HBAs). The hydrogen-bonding interactions between the starting materials were determined. The efficiency of the LTTMs in removing lignin from oil palm biomass residues, empty fruit bunch (EFB) was also evaluated. The removal of amorphous hemicellulose and lignin after the pretreatment process resulted in an enhanced digestibility and thermal degradability of biomass.

Solid Electrolyte Gas Sensor Based on a Proton-Conducting Graphene Oxide Membrane.

Graphene oxide (GO) is an ultrathin carbon nanosheet with various oxygen-containing functional groups. The utilization of GO has attracted tremendous attention in a number of areas, such as electronics, optics, optoelectronics, catalysis, and bioengineering. Here, we report the development of GO-based solid electrolyte gas sensors that can continuously detect combustible gases at low concentrations. GO membranes were fabricated by filtration using a colloidal solution containing GO nanosheets synthesized by a modified Hummers' method. The GO membrane exposed to humid air showed good proton-conducting properties at room temperature, as confirmed by hydrogen concentration cell measurements and complex impedance analyses. Gas sensor devices were fabricated using the GO membrane fitted with a Pt/C sensing electrode. The gas-sensing properties were examined by potentiometric and amperometric techniques. The GO sensor showed high, stable, and reproducible responses to hydrogen at parts per million concentrations in humid air at room temperature. The sensing mechanism is explained in terms of the mixed-potential theory. Our results suggest the promising capability of GO for the electrochemical detection of combustible gases.

Practicality of the suicidal germination approach for controlling Striga hermonthica.

BACKGROUND: Purple witchweed (Striga hermonthica), Orobanchaceae, is an obligate root-parasitic weed of important cereal crops. The parasite is a copious seed producer, and a huge seed bank develops soon after the onset of the initial infestation. To germinate, a Striga seed requires a pretreatment in a moist warm environment and a subsequent exposure to an exogenous stimulant. One approach to reduce the seed bank is artificially to induce germination of the seeds in the absence of or away from the host roots. A newly developed germination stimulant for S. hermonthica, designated as T-010, was evaluated for efficacy in greenhouse and field experiments under artificial Striga infestation. RESULTS: T-010 displayed germination-inducing activity in soil. Formulated T-010 applied at 0.1, 1 and 10 kg ai ha-1 to potted soil containing S. hermonthica seeds, previously conditioned by judicious irrigation, reduced Striga emergence by 94-100%. Results of a field trial showed that formulated T-010, at the same rates as for the pot experiment, delayed and reduced Striga emergence by 33% and increased sorghum shoot and head dry weight by 18.7-40.2% and 187-241% respectively. CONCLUSION: These findings demonstrated, for the first time, the technical feasibility of suicidal germination for controlling S. hermonthica. Optimising structure, formulation and application protocol of germination stimulants should be the main goal for further improvement of the technology. © 2016 Society of Chemical Industry.

Characterization of natural low transition temperature mixtures (LTTMs): Green solvents for biomass delignification.

The aim of this work was to characterize the natural low transition temperature mixtures (LTTMs) as promising green solvents for biomass pretreatment with the critical characteristics of cheap, biodegradable and renewable, which overcome the limitations of ionic liquids (ILs). The LTTMs were derived from inexpensive commercially available hydrogen bond acceptor (HBA) and l-malic acid as the hydrogen bond donor (HBD) in distinct molar ratios of starting materials and water. The peaks involved in the H-bonding shifted and became broader for the OH groups. The thermal properties of the LTTMs were not affected by water while the biopolymers solubility capacity of LTTMs was improved with the increased molar ratio of water and treatment temperature. The pretreatment of oil palm biomass was consistence with the screening on solubility of biopolymers. This work provides a cost-effective alternative to utilize microwave hydrothermal extracted green solvents such as malic acid from natural fruits and plants.

Supercritical carbon dioxide extraction of fucoxanthin from Undaria pinnatifida.

Undaria pinnatifida, commonly known as wakame in Japan, is one species of brown seaweeds containing valuable bioactive organic compounds such as fucoxanthin, a carotenoid, which has numerous functional properties. However, most of the seaweeds that do not meet strict quality standards are normally discarded as wastes or returned to the sea, a situation which is becoming an environmental concern. In this research, supercritical carbon dioxide (SCCO2) extraction was investigated for the isolation of fucoxanthin. SCCO2 extraction experiments were carried out at temperature range of 25-60 °C and pressure range of 20-40 MPa, at a carbon dioxide flow rate of 1.0-4.0 mL/min. Results showed that fucoxanthin recovery closed to 80% could be obtained at 40 °C and 40 MPa in extraction time of 180 min. The recovery increased with decreasing temperature and increasing pressure. Pretreatment with microwave (MW) also enhanced the efficiency of extraction due most likely to disruption of the cell membrane. Application of SCCO2, generally regarded as safe and environmentally benign solvent, for extraction of useful bioactive compounds from unwanted or substandard seaweeds look promising in the near future. The extracts obtained using the method can be utilized as food and pharmaceutical additive, and can be used in the development of new health supplements.

Uncatalysed wet oxidation of D-glucose with hydrogen peroxide and its combination with hydrothermal electrolysis.

An increasing interest in biomass as a renewable feedstock for the chemical industry has risen over the last decades, and glucose, the monomer unit of cellulose, has been widely studied as a source material to produce value-added products such as carboxylic acids, mainly gluconic and formic. In this work, the non-catalysed wet oxidation of glucose using hydrogen peroxide has been analysed, obtaining molar yields to gluconic and formic acids up to 15% and 64%, respectively. Glucose conversion was generally between 40 and 50%, reaching over 80% under the highest temperature (200°C). An appropriate choice of temperature can tune product distribution as well as reaction rates. The interaction of the wet oxidation with an electrolytic reaction was also analysed.

Structural requirements of strigolactones for germination induction of Striga gesnerioides seeds.

Strigolactones are highly potent germination stimulants for seeds of the parasitic weeds Striga and Orobanche spp. 4-Hydroxy-GR24 and 4-acetoxy-GR24 were prepared and their abilities to induce seed germination of Striga gesnerioides evaluated. Optically active (8bR,2'R)-isomers induced germination, although the racemic diastereomers were inactive. In contrast, the stereoisomer of GR24 with the same configuration induced negligible germination. Some stereoisomers of GR24 and its analogues acted as effective antagonists for induction of seed germination by cowpea root exudates. These results suggest that both an oxygenated substituent at C-4 and the configuration of the tricyclic lactone and the D-ring are essential structural requirements for induction of germination in S. gesnerioides seeds.

Identification of 3-aminomethyl-1,2-dihydro-4-phenyl-1-isoquinolones: a new class of potent, selective, and orally active non-peptide dipeptidyl peptidase IV inhibitors that form a unique interaction with Lys554.

The design, synthesis, and structure-activity relationships of a new class of potent and orally active non-peptide dipeptidyl peptidase IV (DPP-4) inhibitors, 3-aminomethyl-1,2-dihydro-4-phenyl-1-isoquinolones, are described. We hypothesized that the 4-phenyl group of the isoquinolone occupies the S1 pocket of the enzyme, the 3-aminomethyl group forms an electrostatic interaction with the S2 pocket, and the introduction of a hydrogen bond donor onto the 6- or 7-substituent provides interaction with the hydrophilic region of the enzyme. Based on this hypothesis, intensive research focused on developing new non-peptide DPP-4 inhibitors has been carried out. Among the compounds designed in this study, we identified 2-[(3-aminomethyl-2-(2-methylpropyl)-1-oxo-4-phenyl-1,2-dihydro-6-isoquinolinyl)oxy]acetamide (35a) as a potent, selective, and orally bioavailable DPP-4 inhibitor, which exhibited in vivo efficacy in diabetic model rats. Finally, X-ray crystallography of 35a in a complex with the enzyme validated our hypothesized binding mode and identified Lys554 as a new target-binding site available for DPP-4 inhibitors.

Degradation of glycerol using hydrothermal process.

Sub-critical or supercritical water was utilized for the degradation of glycerol in an environmentally benign reaction. The reaction was carried out in a batch reactor in the temperature range of 473-673 K, pressure of 30 MPa, and reaction time of 20-60 min. The effects of temperature and reaction time were observed. The degradation of glycerol produced acetaldehyde, acrolein, allyl alcohol and un-identified products. The highest yield of acrolein, acetaldehyde and allyl alcohol were 0.20, 7.17, 96.69 mol%, respectively. Glycerol conversion was 99.92 mol%. While acetaldehyde was formed only in sub-critical water and allyl alcohol only in supercritical water, acrolein was formed in both. The kinetics of the global reaction displayed a pseudo-first-order. The activation energy at subcritical water was 39.6 kJ/mol. Based on the results, this method could be an efficient method for glycerol degradation because the high conversion of glycerol was obtained.

Complete degradation of Orange G by electrolysis in sub-critical water.

Complete degradation of azo dye Orange G was studied using a 500 mL continuous flow reactor made of SUS 316 stainless steel. In this system, a titanium reactor wall acted as a cathode and a titanium plate-type electrode was used as an anode in a subcritical reaction medium. This hydrothermal electrolysis process provides an environmentally friendly route that does not use any organic solvents or catalysts to remove organic pollutants from wastewater. Reactions were carried out from 30 to 90 min residence times at a pressure of 7 MPa, and at different temperatures of 180-250°C by applying various direct currents ranging from 0.5 to 1A. Removal of dye from the product solution and conversion of TOC increased with increasing current value. Moreover, the effect of salt addition on degradation of Orange G and TOC conversion was investigated, because in real textile wastewater, many salts are also included together with dye. Addition of Na(2)CO(3) resulted in a massive degradation of the dye itself and complete mineralization of TOC, while NaCl and Na(2)SO(4) obstructed the removal of Orange G. Greater than 99% of Orange G was successfully removed from the product solution with a 98% TOC conversion.

Nickel removal from nickel-5,10,15,20-tetraphenylporphine using supercritical water in absence of catalyst: a basic study.

Reactions of nickel-5,10,15,20-tetraphenylporphine (Ni-TPP) were studied in supercritical water in the presence of toluene without the addition of any catalyst, H(2) or H(2)S that is called a green process. The objective of this study was to remove nickel from Ni-TPP, the most common metal compound present in heavy crude, in high extent at low reaction time. All experiments were carried out in an 8.8 mL batch reactor fabricated from hastelloy C-276. The ability of supercritical water (SCW) to remove nickel from Ni-TPP was studied at temperatures of 450-490 °C and water partial pressures of 25-35 MPa. Water partial pressure had no effect on overall conversion at temperatures of 450 °C and a reaction time of 60 min. The overall Ni-TPP conversion was 89.80%, a figure above that of previous catalytic studies. The percentage of nickel removal was estimated as a function of reaction time and temperature. It were temperature 490 °C and pressure 25 MPa at reaction time 90 min where 65.68% nickel were removed by the action of SCW and toluene, as a co-solvent. It was determined that Ni-TPP undergoes a series of reactions, ending in demetallation and ring fragmentation. The obtained results suggest that supercritical water has a capability to remove nickel from Ni-TPP.