Potential Applications of PHA

Abstract Polyhydroxyalkanoate (PHA) is an attractive material because it can be produced from renewable resources and because of its plastic-like properties. In addition, PHA can be degraded by the action of microbial enzymes. Although PHA resanbles some commodity plastics, the performance and cost of PHA are not yet good enough for widespread applications as plastic materials. Therefore, the PHA commercialization attempts by many industries for bulk applications have been challenging. However, PHA also possesses interesting properties that can be developed for non-plastic applications. This chapter describes some new niche applications for PHA in cosmetics and wastewater treatment. 

Keywords Batik dye Cosmetics Electrospinning Facial oil Toxicity studies Oil blot Polyhydroxyalkanoate (PHA) Polyhydroxybutyrate (PHB) 

Sudesh, Polyhydtvxyalkanoates from Palm Oil Biodegradable Plastics, SpringerBriefs in Microbiology, DOI 10.1007/978-3-642-33539-6 6, 

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Besides the fabrication of PHA films for oil blotting application, the hydrophobic property of PHA has also led to the use of this material for dye removal via adsorption in textile wastewater treatment. The potential application of PHA films as facial oil adsorbing material suggested that PHA films can also be used to adsorb other hydrophobic compounds. Many textile dyes are hydrophobic and may readily adsorb onto PHA films. Therefore, PHA films maybe used to remove textile dyes from wastewater. Solvent-cast P(3HB) films were found to remove approximately 38 % of color from textile dye wastewater. Electrospun PHA films may show better ability in adsorbing hydrophobic textile dyes. 

Another potential application of PHA is as biomimetic adsorbents for wastewater purification. Wei and co-workers [36] prepared a new biomimetic adsorbent using a lipid-derived P(3HB) homopolymer. 

The diverse potential applications of PHA in a number of fields demanded the production of smart polymers with minimal toxic impurities. Chemical modification methods are sometimes aggressive, and lead to reduced polymer molecular weight, unwanted side reaction(s) and toxic impurities. In some instances, a mild surface modification process is required without which the polymer may fail in its intended application(s). For example, neat polymer without the proper modification may cause delamination of adhesive bonds, poor cellular attachment, permanent staining of a fabric, or may influence proteinaceous membrane fouling etcJ These and many other reasons necessitate the application of physical methods (Table 7.1) in polymer modifications, as explained in the subsequent sections. 

In the first half of the 1960s, potential application of PHA had already been recognized, as shown in that time patents related to production methods by fermentation and extraction of produced biomass. However, manufacturing plastics with petrochemical origin was easy and less expensive, and there was not strong public interest in environmental issues, the industrial use of natural plastics was still unfeasible (Braunegg et al. 1998). 

Polyhydroxyalkanoic acids (PHAs) have been extensively researched since the 1970s because of the potential applications of these compounds as biodegradable substitutes for synthetic polymers. The most successful PHA products are the polyhydroxybutyrates (PHBs). The bacterium... 

Low-cost PHAs would not only benefit the PHA material application as bioplastics, but promote the application of PHAs as biofuels as well. There is a large potential for compromise in this area, as low-cost PHAs could also be obtained from activated sludge and wastewater fermentation, so it will not run into the controversy of food versus fuel or fuel versus arable land. Plant production of PHAs could become a reality, as indicated by some promising results, in the foreseeable future. 

Polyhydroxyalkanoate is a polyester identified in 1925 by the microbiologist Maurice Lemoigne. It can be synthesised by various bacteria (Alcaligenes Eutrophus, cyanobacteria). Lower concentrations of carbon, nitrogen and phosphorus sources increase the yield and the quality of the polymers produced (Steinbiichel, 2002). There are numerous potential applications for PHA (cosmetics containers, disposable articles, medical implants, paper coatings). Moreover, PHA can be formulated in many grades, from elastic products to crystalline ones, it is a good candidate for blends and easy to process with traditional equipment (Whitehouse, 2000). 

Process Hazard Analysis (PHA) can be defined as the application of a systematic method to a process design in order to identify potential hazards and operating problems. It determines the causes and consequences of abnormal process conditions that arise from equipment failure, human error or other events. The goal is to determine whether opportunities exist to reduce the risks of the toll s hazards and then to implement warranted action items. The AJChE CCPS guideline Guidelines for Hazard Evaluation Procedures, Second Edition with Worked Examples is a good resource for fully detailed approaches to process hazard analysis. It provides an introduction to hazard evaluation as well as guidance on ... 

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