Hydrothermal (HT) Processing of Plant Biomass for Petrochemical and Bioenergy Products

INTRODUCTION

Plant biomass represent a vast, renewable source of biobased feedstocks for chemical and thermal processing into biobased energy and petrochemical products. This ongoing research uses hydrothermal (HT) treatment, which simply refers to chemical reactions conducted in water that has been heated (200-600 ºC) and pressurized (50-500 bar) in the absence of dissolved molecular oxygen. Water under these conditions has very unusual properties, and a mixture of water and biomass can rapidly be transformed to products that contain many of the long-chain hydrocarbons present in modern combustible fuels.

HT conditions provide for reactions that are not achievable in other common treatment settings (e.g, pyrolysis, superheated steam, organic reaction systems, liquefaction and gasification). HT systems allow for biomass conversions to industrially useful or energy-yielding chemical mixtures in configurations that allow for (1) recovery of carbon, (2) detoxification of many pollutant organic chemicals, (3) recovery of elements including toxic metals and (4) recycling of heat and water in a closed-loop configuration.

Previous HT transformation studies were generated under simple reaction conditions (i.e., the substrates were mixed with tap water, sealed in a metal reactor vessel, treated in heated water under pressure with no added reactants or catalysts) with the intention of (1) estimating gas-phase and semi-volatile hydrocarbon yields, and (2) identifying the most abundant hydrocarbons generated in this process.

Research to date has demonstrated the technical applicability of HT processing for a wide range of plant biomass types, including invasive plant species and preservative-treated wood waste, both of which have little or no economic value and represent an environmental and ecological problem. This paper will summarize our results using various plant feedstocks for HT treatment with respect to hydrocarbon yields, chemical composition of semi-volatile mixtures and volume reduction.

Preservative-treated Wood

Currently most decommissioned preservative-treated wood is disposed in landfills. This option is neither environmentally friendly nor economically advantageous for those disposing large volumes of treated material (e.g., utility and telecommunication industries). Since nearly half of all southern pine is preservative-treated, it is important for Louisiana forest landowners that the wood-preservation industry remain solvent so forest landowners can obtain maximum value for their timber.

Past research has extensively looked at the feasibility of HT to detoxify preservative-treated wood. The preservatives of interest have included chromate copper arsenate (CCA), creosote and pentachlorophenol (penta). We found that during treatment, the creosote-derived hydrocarbon residues in the wood were nearly completely recovered, and the wood itself was transformed into a mixture of hydrocarbons. These wood-derived transformation products served to reconstitute the “light end” of the creosote, which largely had been lost via leaching while in service. Thus, the hazardous waste (creosote-hydrocarbon mixture) was recovered, and the solid waste (wood) was transformed into a complimentary product mixture in a single pass. For the CCA- and penta-treated wood studies, wood particles were transformed into liquid and gaseous hydrocarbon mixtures irrespective of pH conditions and preservative.

It is cumbersome to segregate decommissioned preservative-treated wood by preservative type. Therefore, a successful recycling method must be able to accommodate mixtures of wood treated with different preservative types. Accordingly, current research is looking at the technical feasibility of HT treatment of equal parts of CCA-treated wood, creosote-treated wood and penta-treated wood. The initial data have shown that during HT treatment, the creosote-derived hydrocarbon residues were recovered in the decommissioned, treated wood and the wood mass itself was transformed into a mixture of industrially useful hydrocarbons. The metals from the CCA-treated wood were partially recovered. It is speculated that some arsenic was transformed into a gas, which could be trapped and recovered under industrial conditions. The penta was detoxified. The HT process also resulted in the generation of industrially useful mixed hydrocarbons with substantial reductions in substrate mass. Thus, the preservative-treated wood was transformed into a liquid mixture that contained many industrially useful products, some of which can be used for bioenergy and others for biobased chemicals.

It is important to note that this work was performed in large reactors, which were heated with hot air in a muffle furnace. Hence the incubation time was long. Our current work with small reactors heated rapidly (under two minutes) in tin baths to 400º C has confirmed that HT reactions occur on the order of seconds to minutes.

Invasive Aquatic Plants

This work examined HT treatment of three invasive aquatic plants (i.e., Lemna sp., Hydrilla sp. and Eichhornia sp.) Identical HT treatments yielded similar semi-volatile product mixtures for Hydrilla. sp. and Eichhornia sp. versus a significantly different mixture for Lemna sp. No semi-volatile hydrocarbons were found in any of the species prior to HT treatment. Post-HT-treatment product mixtures were composed of complex mixtures of compounds. All three plant HT product mixtures were dominated by compounds found in the top 100 industrially useful chemicals.

Results of wet chemical analyses showed that a major difference between Lemna sp. and the other two plants was significantly higher extractives levels in the former. It was found that this fraction accounted for much of the complexity in the post-HT treatment liquid of the Lemna sp. biomass. For all HT treatments, the substrate mass was reduced by 95% or more.

Chinese Tallow Tree

The principal tree species investigated to date is the Chinese tallow tree (Triadica sebifera [syn. Sapium sebiferum]. The species is extremely well adapted to numerous environments, and there are no known diseases that debilitate it. Also, it produces aboveground biomass at a significantly faster rate than most other tree species and is able to establish a dense stand quickly.

Work to date has explored the potential of Chinese tallow tree (wood/bark, leaves and seeds) as a raw material for biobased chemical and energy production using hydrothermal (HT) conversion. Seeds were HT treated as both whole and ground. Ground wood/bark, leaves and seeds yielded similar aromatic compound assemblages after HT treatment. Ground seeds yielded unique minor byproducts and did not contain naphthalene, which was present in the other tissue types. Whole HT-treated seeds yielded a material that resembled asphalt in appearance, odor and chemical properties but did not produce any phenol. In contrast, ground seeds did not yield any particulate matter and had substantial amounts of phenol.

With regards to the energy input/output of this work, the HT treatment had a fairly neutral effect on energy content of the tallow seeds. The energy values of the tallow seeds are much higher than those typically reported for hardwood stemwood.

Conclusions

In recent years, the authors have documented the transformation of underused biomass (WB) into gas phase and semi-volatile hydrocarbon mixtures in hydrothermal (HT) reaction systems. HT systems allow for biomass conversions to industrially useful or energy-yielding chemical mixtures in configurations that allow for (1) recovery of carbon as volatile and semi-volatile petrochemicals, (2) transformation of many pollutant organic chemicals, (3) recovery of elements including toxic metals and (4) recycling of heat and water in a closed-loop configuration. Studies to date have documented treatability efficiencies on the order of 90-99% on a mass basis and the generation of saleable and/or value-added chemical product mixtures including volatile and semi-volatile compounds including over one dozen chemicals in the top 100 commercial petrochemicals.

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Stabilizing and Bending of WOOD for the Hobbyist

Lumber scraps and cross-sections of angle cuts sawed from small logs or large limbs can be made into attractive items, but only if the wood is first treated with polymers and then properly seasoned, or if the wood is initially seasoned following special techniques. These treatments and techniques can result in profitable uses of “low grade” logs and oddly shaped scraps that might otherwise be discarded. This publication describes some techniques of stabilizing and bending wood for hobbyists.

Freshly cut cross-sections normally check badly and develop typical pie-shaped or vshaped cracks during the drying process. This is because wood shrinks twice as much in the tangential direction (parallel to the annual rings) as in the radial direction perpendicular to the annual rings). The internal stresses that result from such differential shrinkage invariably cause serious checks and splits as the wood loses moisture and comes to moisture content (MC) in a heated or air-conditioned wood shop. These are some of the techniques for drying wood cross-sections. These techniques can also be used for lumber scraps.

PEG-1000 Chemical Treatment

One method recommended often in recent years is stabilization of wood with a bulking agent such as polyethylene glycol (PEG). PEG treatment requires soaking the wood for a long time. This tends to darken the sapwood. Also, PEG is hygroscopic and raises the MC of the wood; under humid conditions, the chemical may cause the finished board surface to develop discolored streaks. To avoid these problems, you must dry the disks without chemicals.

Many hobbyists use PEG as a bulking agent that greatly reduces the dimensional changes of green wood. PEG is a white, wax-like chemical that resembles paraffin, is solid at room temperature, has an average molecular weight of 1000 and dissolves readily in warm water. PEG melts at 104 degrees Fahrenheit, is nontoxic, noncorrosive, odorless, colorless and has a very high firing point (580 degrees Fahrenheit). It is chemically related to antifreeze.

The PEG treatment, which physically bulks the wood cell walls (fibers), prevents shrinkage and thus prevents the development of destructive stresses (figure 1.). Green wood heavily treated with PEG retains its “green dimensions” indefinitely, and thus is permanently restrained from shrinking, swelling or warping, regardless of humidity changes.

To read more please visit our publication: Stabilizing and Bending of WOOD for the Hobbyist

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Wood – Its Nature and Properties for Woodworking

For most cabinetmakers and furniture makers, wood is the raw material of choice. Wood has thousands of uses. Although wood may appear to be a relatively simple substance, closer examination shows that wood is one of the most complicated and unusual natural materials. The more you know about wood and its properties, the more valuable wood can become to you.

Wood is made up of many tiny tubular cells which are held together by the wood’s own cement, lignin. These tubular cells are similar to a bundle of drinking straws (see Figure 1). These cells carry the supply of necessary nutrients and water which nourish the life processes of the tree. The walls of these cells also provide support and strength to the tree. These cells run up and down the tree, and produce grain that is visible on the cut surfaces and edges of lumber.

Each of the cells is very narrow and rather long. These cells consist of a cell wall and a cell cavity (lumen) inside the cell wall (see Figure 2). Most of the cells in a tree are dead. The only living cells in a tree are the recent growth produced by the cambium (how the tree grows in width) and some cells in the sapwood.

When the wood is sawn, the openings in the cells are exposed, forming openings on all the wood surfaces. These openings are small pores, and the quantity of pores is called porosity. This porosity is quite extensive. This structure of open space and cell walls gives wood its strength and its properties.

Hardwoods and Softwoods

The terms hardwood and softwood are botanical terms and do not indicate the actual hardness or softness of the wood. Some hardwoods are softer than some softwoods, and vice versa. Hardwoods are actually broadleaf trees. Some examples of hardwoods include walnut, oak, ash, maple, cherry and mahogany. Softwoods come from conifers, which are actually trees that bear cones or have needle-like leaves. Some examples of softwoods are the southern yellow pines, white pines, fir, cedar and redwood. Figure 3 compares the softwoods and hardwoods.

Hardwoods and Softwoods

The growth ring is often used in reference to the annual growth of a tree. The rings are not always as easy to see as the ones shown in Figure 4. Some woods do not show any visible indications of annual growth. Some species have quite distinct growth rings; others are not easily visible.

The growth rings of wood are made of springwood and summerwood. The portion of the growth ring formed early in the growing season is called the springwood or early wood. That which forms later in the season is called the summerwood or late wood. Generally, the springwood has larger cell cavities and thinner walls, and is less dense than the late wood (see Figure 2).

Hardwoods are classified into three groups, based on the pattern of growth of the annual rings:

Ring-porous species have springwood cells that are wide and distinct, usually several cells wide. The summerwood cells are small, indistinct and thick walled, making the rings very distinct. Some examples are oak and ash. Figure 5 illustrates a ring porous wood, red oak.

Semi-ring porous (semi-diffuse porous) species have fairly distinct springwood cells but are not as wide and obvious as the ring-porous wood. The summerwood, which comprises most of the annual growth ring, has distinct, thick cell walls. Some examples are black walnut and pecan. Figure 6 shows a semi-ring porous wood, black walnut.

Diffuse porous species have no distinct difference between the springwood and summerwood and no distinct ring or annual grain patterns. Some examples of diffuse porous woods are birch, poplar, basswood, maple and cherry. Figure 7 shows a diffuse porous wood, maple. Structural arrangement of wood.

To read more please visit our publication: Wood – Its Nature and Properties for Woodworking

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Why and How to Market Wood Products

This publication is designed to educate small to medium size primary and secondary forest products industry personnel about why and how to market wood products. Hobbyists and producers of wooden arts and crafts will also benefit by learning the necessary marketing skills to increase revenue and make their part-time business or hobby less expensive.

The Louisiana forest products industry has a reputation as a leader in the quantity and quality of primary forest products (lumber, plywood, etc.) and secondary forest products (furniture, cabinets, millwork, etc). As the population of the state, country and world continue to grow, the demand for wood products will increase. In Louisiana, the competition for wood products customers increases each year as large and small primary mills open, dry kiln capacity increases and numerous secondary companies open or expand. Therefore, proper marketing skills are essential for the industry to grow and prosper.

We welcome your comments on this publication and look forward to hearing from you. Your first source of information on forest products marketing or forestry in general is your Louisiana Cooperative Extension Service county agent. Please stop by your parish office to learn more about the programs available to you.

What is marketing?

Marketing is defined differently by different people. Some business managers think marketing means selling, advertising, packaging or distribution. All of these ideas are important to marketing, but they don’t define marketing properly. Marketing can be thought of as a total system of business activities designed to determine customers’ needs and desires, then to plan and develop products and services to meet those needs and desires, and then to determine the best way to price, promote and distribute the products and services.

People often confuse marketing with other terms. For example, markets and marketing are not the same. Markets are the customers. Also, many people think marketing and selling are the same. A short explanation is that selling focuses on the product. A company sells what it can make. A company that markets what it can sell, however, focuses on the customer rather than the products. This difference is critical to a successful marketing plan.

Two important concepts about marketing are related to selling. First, the entire system of business activities should be customer-oriented. Consumers’ wants must be recognized and satisfied. Second, marketing should start with an idea about a want-satisfying product and should not end until the customers’ wants are completely satisfied, which may be some time after the exchange is made. The emphasis here is on the customer rather than the selling of the product.

To read more please visit our publication: Why and How to Market Wood Products

 

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Causes and Control of Wood Decay, Degradation, and Stain

Our society depends on wood for a variety of uses. As population increases, so does our need for wood. Steel, concrete and aluminum are some alternatives to treated wood in certain applications, but they have higher material costs, higher energy requirements in the production process, greater air and water pollution or environmental protection costs, and greater dependency on foreign sources for materials.

Substitute materials may not be appropriate for some uses. For example, some types of steel may corrode; concrete may deteriorate in salt water; and plastic may not have the necessary strength, durability and structural integrity. Wood is a renewable natural resource that, if properly treated, maintained and placed in service, will last indefinitely. It is critical for us to use our wood resource efficiently.

This publication is intended to increase your knowledge of the causes and control of wood decay, degradation and stain. A common cause for replacing wood structures is decay or degradation. Wood decay and most insect problems can be prevented for years by properly using and protecting wood. The heartwood of some species, such as black locust and Osage orange, also has a unique chemical composition that makes it very durable.

Two common terms used to describe wood features are heartwood and sapwood. Heartwood is wood in the inner section of a log and is entirely composed of dead cells. This region has a higher concentration of extractives (phenolic-based compounds that make heartwood more decay resistant than sapwood). Sapwood is wood near the bark and is often lighter in color than heartwood. Nutrient translocation occurs only in sapwood. Although most wood species can be treated with a preservative, certain species are considered difficult to treat because of their permeability and anatomical features. Douglas fir, a western species, has below-average permeability and is classified as difficult to treat. Species such as white oak have inclusions in the vessels called tyloses. These inclusions also decrease permeability and make treating more difficult. In general, lumber that has a high percentage of heartwood or is improperly seasoned will be more difficult to pressure treat. Southern yellow pine (SYP) characteristics make it useful for many applications and easily treatable. Most pressure-treated lumber in the South is Southern yellow pine.

Moisture

It is commonly believed that wood shrinks as it loses moisture and swells as it gains moisture. This is partially true. Actually, wood will change dimension only between two precise moisture conditions. One condition is when the wood is void of moisture. This is termed the ovendry condition. The second condition is when the wood fibers are saturated with moisture. This point usually occurs at about 30 percent moisture content for most Louisiana species. As wood is dried from an original green condition, sometimes more than 100 percent moisture content, moisture is first lost from the cell cavities. No shrinkage will occur until the wood reduces to a moisture content of about 30 percent (fiber saturation point). If drying continues below 30 percent moisture content, water is removed from the cell walls and shrinkage occurs. The amount of shrinkage or swelling depends on the species, density and board direction.

Pressure treatment with waterborne preservatives raises the moisture content above the fiber saturation point, and shrinkage will occur as the wood dries down to its in-service moisture content. In many applications, such as deck boards, this shrinkage is not a major concern. When dimensional stability is critical, it is imperative that the lumber be kiln dried after treatment (KDAT). Any KDAT lumber you buy should be kept under a roof or at least under cover and off the ground.

To read more please visit our publication: Causes and Control of Wood Decay, Degradation & Stain

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Wood Chair Safety

Wood is frequently used to construct a wide array of chairs for use at the home, office, restaurants, hotels and other establishments. These chairs range from simple four-legged, school-style chairs to three-legged bar stools. Wood is an excellent choice for chairs due to its inherent beauty and durability if properly maintained.

I have been an expert witness in legal cases involving failure of wooden chairs and many of which could have been prevented.  Chair accidents are often not the result of a single incident but rather the culmination of years of abuse or neglect. Wood and metal both can degrade over time, especially in humid or other adverse conditions. Metal fasteners are subject to corrosion and can fail due to repeated or excessive wear due to a condition known as metal fatigue.

Accidents are due to a problem in at least one of these three areas: (1) improper maintenance, (2) design defect and (3) manufacturing defect. The more of these areas that you can control, the lower your risk of a chair-related accident.

Maintenance

Wood chairs should be routinely inspected to help ensure that the chair will perform as it is intended and in a safe manner. Homeowners should follow these simple guidelines when inspecting their chairs. Inspection will not guarantee you will not have an accident but will certainly reduce the risk.

Does the chair appear stable or does it wobble? Is any of the wood soft or display evidence of insect attack?
Do the joints appear solid? Pieces of wood were either joined with glue or a fastener. In either case, the joint can degrade over time, and the integrity of the joint can be examined visually and by applying different loads to the chair.

Design

Homeowners are typically not responsible for the design of the chair. If a product has a design defect, then all of the products manufactured using this design are flawed and dangerous. A product can have a design defect if a foreseeable risk of harm could have been reduced or otherwise eliminated by using an alternate design and the failure to use such an alternate design resulted in an unsafe condition. A chair may be safe for a large person to gently sit but may fail if the person abruptly sits down. Such a chair may be designed for a static load rather than a dynamic load and if so would have a design defect.

Many chair accidents involve the failure of a critical load-bearing component. This is generally classified as a design failure. Common design defects include improper sizing or bracing of chair legs.

Manufacturing

Again, homeowners are typically not responsible for the manufacturing of a chair. Manufacturing defects occur due to mistakes or other problems during the assembly of the product. So, in this case, some of the products using a given design are safe and others are unsafe. Manufacturing defects can occur if another species or grade of wood is used rather than what was specified in the design. A common manufacturing defect is a “starved” glue joint. This occurs when either too little glue is used or too much pressure is applied to a glue joint and results in an inadequate amount of glue in the joint. The joint is then compromised and subject to failure.

Disclaimer

This article is not intended as a substitute for legal advice for individuals involved in a chair-related accident nor should it be interpreted as legal advice or opinion. This article is based on available information as of the time of its posting and is intended for general information purposes only. All users of chairs are encouraged to read and follow proper safety rules and be familiar with all applicable government regulations and standards before using a chair.

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Wood from a West Coast Cedar Tree May Help Find a Cure for Prostate Cancer

Natural Drugs

If a man lives long enough, he will develop prostate cancer.  The many commercially available anticancer drugs can be classified by origin as either chemical synthetic drugs or natural drugs derived from various kinds of organisms. Natural medicine for cancer therapy has proved to be effective and less toxic on normal cells, with fewer side effects. Prodigiosin did not cause death in vitro to lymphocytes at effective concentrations (<100 nM) and also did not show toxicity in vivo to lymphoid organs at effective dosages (10 and 30 mg/kg). The discovery of anticancer drugs has mainly resulted from screening of natural products and their analogs. Some natural plant metabolites are believed to have anticancer properties; these include several pigments, quinines, and alkaloids. Secondary metabolites from microorganisms are more practical for development as therapeutic agents.

Prodigiosin

As an anticancer drug, prodigiosin shows its anticancer activity by inhibiting or activating some signaling pathways that have not been clearly understood before. Prodiginines (PGs) are a family of tripyrrole red pigments receiving increasing interest because of their numerous biological activities, including antifungal, antibacterial, antiprotozoal, antimalarial, immunosuppressive, and anticancer activities. Specially, prodigiosin has been effective in tumor cell inhibition and cell apoptosis induction. Prodigiosin is a secondary metabolite produced from Serratia species and other unrelated microbial strains, such as Streptomyces griseoviridisPseudomonas magnesioruberaVibrio species, and other marine bacteria. Some of the enzymes involved in the biosynthetic pathways that produce prodigiosin are now known, and some of the corresponding genes have been identified and cloned, but the biosynthetic pathway is still poorly understood. Prodigiosin production in some producer organisms, such as Serratia and Streptomyces, is now well understood, as well as its physiology and regulation. However, its biological role in these organisms remains unclear.

Fixation is a chemical process in which the preservative chemically bonds to the wood. It is well recognized that exposure of CCA-treated wood to an acid solution can re-oxidize the chromium thereby converting the CCA elements into their water-soluble form. Thus, acid extraction using different acids and wide ranges of reaction conditions has been extensively studied for removal of CCA from out-of service CCA-treated wood (Shiau et al. 2000; Clausen 2004; Humer et al. 2004; Kazi and Cooper 2006; Gezer et al. 2006; Kakitani et al. 2007; Janin et al. 2009). These studies have shown that the recovery of CCA elements from CCA-treated wood can be obtained with many organic acids, such as oxalic, acetic, citric, and formic acids; however, the acid extraction process is slow. Therefore, cost-effective acid extraction methods are lacking.

Chamaecyparis lawsoniana 

Chamaecyparis lawsoniana is known to have significantly high levels of natural durability and termiticidal activity due to the inherently high attractive content of its heartwood. In this paper, we described the isolation of a prodigiosin-producing bacterium, HDZK-BYSB107, collected from Port Orford Cedar (POC), Clawsoniana, in Oregon, USA. The prodigiosin-producing strain was identified as Serratia marcescens subsp. lawsoniana. We extracted and purified a red pigment from this strain and identified it as prodigiosin by ultraviolet absorption analysis, mass spectrographic analysis, LC-MS, and NMR spectroscopy. Therefore, to explore the anticancer activities and mechanism of the bacterial prodigiosin, we performed this study using human choriocarcinoma (JEG3) and prostate cancer cell lines (PC3) in vitro, and JEG3 and PC3 tumor-bearing nude mice in vivo.

Findings

 Our results suggested that the bacterial prodigiosin had strong antibacterial, anticancer, and proapoptotic activities against cancer cells and raises the possibility of its use as a chemotherapeutic drug in future.  Together with its excellent anticancer activity, the anticancer mechanism was further verified by JEG3 and PC3 cells. We confirmed that the bacterial prodigiosin promotes cancer cell apoptosis. Thus, we concluded that the HDZK-BYSB107 prodigiosin could be considered as a non-toxic anticancer drug in the near future.

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Rapid Recovery of Metals in CCA-treated Wood

 ABSTRACT

The recovery of heavy metals from chromated copper arsenate (CCA)-treated southern pine wood particles was investigated using binary acid solutions consisting of two of acetic, oxalic, and phosphoric acids in a microwave reactor. Formation of an insoluble copper oxalate complex in the binary solution containing oxalic acid was the major factor for low copper removal. Furthermore, the possible complexation of acetic/oxalic acid in the organic phase, the decomposition of oxalic acid in acetic acid at high temperatures, and the promotion of the formation and precipitation of the copper oxalate by phosphoric acid may induce an antagonistic effect which adversely influenced the effectiveness of the copper extraction. It was found that the addition of acetic acid into phosphoric acid enhanced the chromium recovery rate of the mixed acid solution. This synergistic effect of mixed acetic acid and phosphoric acids is considered one of the most interesting and significant discoveries in the study. The minimal reaction conditions for extracting the maximum percentage of metals was 2.75% phosphoric acid, 0.5% acetic acid, and 130°C. The total recovery rate approached 100% for arsenic, 96.7% for chromium, and 98.6% for copper in a one step process.

INTRODUCTION

Preservative-treated wood products are well known to significantly prolong service life, and thereby extend the forest resource and enhance its sustainability. Inevitably, however, the treated products will become unserviceable either due to mechanical damage or failure, biological deterioration, or obsolescence. It is estimated that approximately 12 million m3 per year of spent CCA treated wood will be removed from service in the United States and Canada in the next 20 years (Kazi and Cooper 2006). Disposal of this material has become a major concern because of its residual toxic chromated copper arsenate (CCA) content, in particular the arsenic and chromium. Previous studies have shown that CCA compounds can be gradually leached into the environment (Townsend et al. 2005; Moghaddam and Mulligan 2008). Conventional waste disposal options for spent preserved wood, such as land-filling, are becoming more costly or even impractical because of increasingly strict regulatory requirements and liability concerns. The burning of treated wood may be extremely dangerous to the environment and human health, particularly if the wood has been treated with CCA. There is an urgent requirement for the development of techniques to effectively recycle decommissioned CCA-treated wood.

Fixation is a chemical process in which the preservative chemically bonds to the wood. It is well recognized that exposure of CCA-treated wood to an acid solution can re-oxidize the chromium thereby converting the CCA elements into their water-soluble form. Thus, acid extraction using different acids and wide ranges of reaction conditions has been extensively studied for removal of CCA from out-of service CCA-treated wood (Shiau et al. 2000; Clausen 2004; Humer et al. 2004; Kazi and Cooper 2006; Gezer et al. 2006; Kakitani et al. 2007; Janin et al. 2009). These studies have shown that the recovery of CCA elements from CCA-treated wood can be obtained with many organic acids, such as oxalic, acetic, citric, and formic acids; however, the acid extraction process is slow. Therefore, cost-effective acid extraction methods are lacking.

Our recent studies on removal of CCA elements from spent CCA-treated wood have focused on the application of the microwave energy to facilitate acid extraction. A preliminary study (Yu et al. 2009) has shown: (1) microwave-assisted acid extractions with oxalic, acetic, and phosphoric acids have reduced the reaction times from hours to minutes compared to the conventional methods, (2) oxalic acid effectively removed arsenic and chromium but not copper, (3) acetic acid extraction was highly effective for the removal of arsenic and copper but not for chromium, and (4) extraction using phosphoric acid was less effective as compared to both oxalic and acetic acids. These results indicated that none of the individual acids were able to effectively remove all three CCA elements simultaneously, but showed a potential complementary effect for extraction. For instance, oxalic acid removed chromium very effectively but not copper, and acetic acid effectively extracted copper but not chromium. The results strongly suggested the opportunity for a two-acid process by either a synergistic extraction effect of the combined acids or a two-step process of consecutive acid extraction. In this study, two acids were mixed, and the extraction potential was evaluated. The acids studied were oxalic, acetic, and phosphoric. The objective of this study was to develop a cost-effective microwave-based dual acids extraction system to maximize removal of CCA elements from spent-CCA-treated wood. This was addressed by optimizing of the acid combinations and concentration, extraction times, and reaction temperature to minimize any environment impact.

To read more please visit our publication: Rapid Recovery of Metals in CCA-treated Wood

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and building materials, wood decay and degradation, and wood science. Shupe worked as a professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the President of the Baton Rouge District of United Methodist Men, and Board Member for Gulf South Men and a Team Leader for The Kingdom Group. He is a volunteer for the Walk to Emmaus, Grace Camp, and Iron Sharpens Iron. Todd is a Men’s Ministry Specialist through the General Commission of United Methodist Men and is in training to be a Certified Lay Minister through the Louisiana Conference of the United Methodist Church.

Influence of solvent type on microwave-assisted liquefaction of bamboo

Influence of solvent type on microwave-assisted liquefaction of bamboo

Microwave-assisted liquefaction of bamboo in glycerol, polyethylene glycerol (PEG), methanol, ethanol, and water were comparatively investigated by evaluating the temperature-dependence for conversion and liquefied residue characteristics. The conversion for the liquefaction in methanol, ethanol, and water increased with an increase in reaction temperature, while that for liquefaction in glycerol and PEG was converse. The results of Fourier transform-infrared spectra for the liquefied residues revealed that cellulose was the main resistance to bamboo liquefaction in methanol, ethanol, and water. Glycerol could be selected as a commendable liquefacient for the solvolysis of bamboo components at low temperature using microwave energy. Moreover, liquefaction behaviors in glycerol and methanol under different temperatures were also distinguished by scanning electron microscopy images.

Bamboo has become one of the most important non-timber forest products in China and other Asian countries. This is primarily due to its rapid growth rate, availability, renewable nature, high productivity, short maturity cycle, and multiple uses. Currently, bamboo has been used in the preparation of high-value added products, such as panel, parquets, furniture, and structural composites. However, in the manufacturing of bamboo-based materials, the epidermis and wax layer of bamboo are usually split off. This is because of the poor wettability or penetration of these portions for subsequent treatments, for example, coating and preservative treatments, etc. Thus, large quantities of bamboo processing residues, such as epidermis, are cast aside as waste.

Recent achievements in techniques for converting woody materials into value-added liquid products under mild conditions using organic solvent and an acid catalyst have stimulated certain studies focused on evaluating bamboo as a raw material for manufacturing bio-products. Several studies have been conducted to formulate liquefied bamboo for bio-polyols and polyurethane foams (Yip et al. 2009; Zhang et al. 2013; Liu et al. 2008; Gao et al. 2010). Although pilot-scale evaluation of liquefied bamboo as chemical feedstocks for the preparation of polyurethane foams have shown encouraging results, an economically viable bamboo waste conversion technology is yet to be realized because of the high cost of the liquefaction process. Alcohols have been proven to be effective solvents for liquefaction of lignocellulosic biomass (Xu et al. 2013; Toor et al. 2013). The benefit from using alcohols in liquefaction is that they can be easily recovered after liquefaction.

Microwave energy has recently been applied in the liquefaction of lignocellulosic biomass (Pan et al. 2012; Li et al. 2013; Xiao et al. 2013). In a microwave heating system, microwave energy penetrates and produces a volumetrically distributed heat source; heat is generated throughout the material and leads to faster heating rate and improved kinetics as compared to conventional heating. However, microwave dielectric heating is based on the ability of a specific reagent or substance to absorb such radiation and convert it into heat at a given frequency (Cinta et al. 2014). Thus, solvents with different specificities that will be applied in a microwave-assisted liquefaction system may have an influence on the liquefaction behavior of biomass. In this study, liquefaction of bamboo with five different solvents (glycerol, PEG, methanol, alcohol, and water) using microwave energy was systematically investigated. The chemical structure and the surface morphology of the liquefied residues from different reaction conditions were comparatively analyzed. The specific objective of the study is to provide a primary understanding of the influence of solvents on the extent of liquefaction with microwave as heating energy.

Todd Shupe is the President of DrToddShupe.com and is a well recognized expert on wood-based housing and wood science.  Shupe worked as a  professor and lab director at LSU for over 20 years. He is active in several ministries including his Christian blog ToddShupe.com. Todd is the Secretary of the Baton Rouge District of United Methodist Men, Database Coordinator for Gulf South Men, and volunteer for the Walk to Emmaus, Grace Camp, Iron Sharpens Iron, Open Air Ministries, HOPE Ministries food pantry. Todd is currently preparing to be a Men’s Ministry Specialist through the General Commission of United Methodist Men.