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Journals

Extracts from Nandini Chemical Journal, May 2007

Toluene diisocyanate|Jatropha biodiesel|Polyvinylidene|Pvdc|Acyclovir
Highlights of Some of the Articles

TALK OF THE MONTH
TOLUENE DIISOCYANATE - INCREASING GLOBAL DEMAND AND MATCHING CAPACITY CREATION
POLYVINYLIDENE CHLORIDE - PROFILE
ACYCLOVIR - ANTI VIRAL DRUG - PRODUCT OUTLOOK
PSYLLIUM - DIETARY FIBER SUPPLEMENT
OTHER STORIES
OTHER ARTICLES

TALK OF THE MONTH

JATROPHA BIODIESEL - WILL THE EUPHORIA BE SUSTAINED?

Not long ago, there was huge euphoria in the country about the prospects for jatropha based bio diesel project. The central government and many state governments formulated number of schemes to promote the cultivation of jatropha and number of seminars and workshops on the subject took place with enthusiastic participants and lofty speeches and presentations. Suddenly now, with the falling trend in the price of international crude, the enthusiasts of jatropha bio diesel project appear to have developed cold feet. Now, a sense of frustration and desperation about the future of the jatropha based bio diesel industry is evident.

Lack of clarity in pricing policy

One of the biggest stumbling blocks for the jatropha bio diesel project in India is the lack of clarity with regard to the Government of India’s pricing policy and programme. It has been repeatedly pointed out that the jatropha bio diesel project cannot take off without the Government of India announcing a firm pricing policy for jatropha bio diesel that would extend subsidy support by the government, so as to ensure competitive price for bio diesel with that of petroleum diesel and financial viability for the project.

Even earlier, several experts pointed out the possibility of the price of crude oil falling down and in that event, the price of the jatropha bio diesel would become uncompetitive in the market.

The government ought to have announced policy on the pricing issues, so as to ensure parity in the price of jatropha bio diesel with that of crude oil and petroleum diesel that would have provided comfort and confidence to the industry. It appears that the government has not applied its mind to the task adequately.

Land availability for cultivation

There is also uncertainty about making adequate area of waste land available for cultivation of jatropha, so that large quantity of bio diesel can be produced that will make a dent on demand for petroleum diesel in India.

There has been no fixing of time bound and quantitative target for the production of jatropha bio diesel and precise estimate of the land required in different states. The availability of adequate land for cultivation of jatropha to meet the production target in different states in India has not been ensured.. Now, many organizations who want to venture into jatropha bio diesel field do not know as to where the jatropha seeds would come from, as allocation of land for jatropha cultivation are yet to be done on the scale required.

The task of procurement of land for cultivation of jatropha has been largely left to the individual organizations, who can do only in small level. Active government participation in the allocation of land for jatropha cultivation in a massive way can alone take the project to the desirable dimensions.

Lack of sale outlet for co product glycerine

A big issue that has been repeatedly pointed out in various forums is the production of glycerine during the trans esterification process of the jatropha vegetable oil for the production of jatropha bio diesel. For every metric tonne of jatropha bio diesel produced , there would be production of 0.25 metric tonne of glycerine as co product in the process. With the demand for glycerine in India being less than 50000 metric tonnes per annum and with glycerine abundantly available internationally due to huge capacity creation for bio diesel abroad , one would not know as to where the glycerine produced from Indian jatropha based bio diesel projects would be sold.

Good price realization for glycerine is an essential aspect for the adequate economics of jatropha bio diesel project. With the surplus availability of glycerine around the world, the price of glycerine is falling down which is threatening to erode the economics of bio diesel project.

Development of alternate applications for glycerine has been pointed out as a matter of vital necessity to increase the demand for glycerine and get good price for glycerine. Unfortunately, adequate research and development efforts have not been put forth in India to develop new applications for glycerine or develop downstream and derivative products based on glycerine. Again, Government of India has failed to put forth an action plan for national level R&D efforts to develop applications for glycerine with the urgency that it deserves.

Threat of import of bio diesel

While jatropha bio diesel projects are confronted with so many issues , now there is threat of import of bio diesel from abroad. If and when this import would take place particularly from South East Asian countries where bio diesel would be produced from palm oil, the Indian bio diesel industry would be left to struggle for survival. One is not sure as to whether the Government has thought about the impact of this development.

With the huge capacity creation for bio diesel around the world and particularly in South East Asian countries and in China, the import threat of bio diesel in India is real.

Fuel Crop vs Food Crop

Finally, there is one argument emerging against the jatropha bio diesel project. Some sources are questioning the advisability of dedicating the land for cultivation of fuel crop at the cost of food crop, when one third of this highly populated country is going without square meal a day.

TOLUENE DIISOCYANATE - INCREASING GLOBAL DEMAND AND MATCHING CAPACITY CREATION

Chemical formula

C 9H 6N 2O 2

Appearance

White to pale yellow liquid

Odour

Sharp pungent odour

Specific gravity

1.22

Solubility

Soluble in ether, acetone and other organic solvents

Product Specification

Description

Analysis

Purity (% by wt.) min.

99.7

Isomer content (% by wt.)
2, 4 TDI
2, 6 TDI

 

80+/-1
20+/-1

Total Acidity (ppm. by wt.) max.

40

Hydrolyzable Chlorine (ppm. by wt.) max.

70

Total Chlorine (ppm by wt. ) max.

700

Sp. gr.(at 20/20)

1.22 +/-0.02

Application

TDI is a vital raw material for flexible polyurethane foam (FPF), for use in cushions, mattresses, garments, pads and gloves and packaging materials, which find application as cushioning material for automobiles, furniture and mattresses.

TDI is also used to produce coatings, rigid foam adhesives, sealants and cast elastomers.

Application sector of Flexible polyurethane foam

Application sector

Nature of application

Furniture

Mattresses, Pillows, Quilts 

Automobiles

Seats, Lining, Sun Visors

Padding & Lining

Garments, Shoes, Diaries, Carpets, Brief Cases, Bags, Purses etc

Packing

Electronic Items, Frozen Foods, Medicines, Audio-Video Computer CD's.

Applicators

Shampoos, Wax, Shoe Polish, Household Chemicals

Miscellaneous

Toys etc.

This article discusses the following details

  • Process outline
  • Technology development by Bayer
  • Source of Technology
  • Global Scenario
  1. Global installed capacity
  2. Regionwise installed capacity
  3. Global producers and their installed capacity
  4. Plant closures
  5. New Projects
  6. Demand drivers and Growth rate in demand
  7. Present Global demand
  • Indian Scenario
  1. Indian producer
  2. Annual imports
  3. Annual exports
  4. Present Indian domestic demand
  • Prognosis
  1. Demand trend
  2. Projected supply scenario
  3. Recommendation
POLYVINYLIDENE CHLORIDE - PROFILE

PVDC resin is a thermoplastic white powder comprising mainly of PVDC.

Its low permeability to a wide range of gases and vapours is the most valuable performance property of PVDC-based polymers.

PVDC latex is a specialty barrier material and used as a coating in packaging applications, where the integrity of the goods is critical, mainly in the food and pharmaceutical sectors.

Classification

PVDC products are classified into:

  • PVDC resin for extrusion, mainly handi wrap, composite films, food bags, multi-layer co-extruded films, casing films etc;
  • Solution type PVDC resin for coatings, mainly used for special coatings
  • Fiber PVDC resin, used in fishing net silk, flame-resistant fabrics, artificial lawns, etc
  • PVDC emulsion, mainly used in composite membranes, films coated in both surfaces, hard plate like composite films, foil composite films, etc. resistance, chemical resistance, and heat sealability can also be added to films by coating with PVDC latex.

Safety and regulation

The powder is essentially non-irritating to the skin, but the dust may cause irritation to the eyes, nose and throat. At high temperatures (200deg C), PVDC resins can decompose and generate hydrogen chloride gas at concentration, which may cause respiratory irritation.

Powders and films are considered safe for humans, wildlife and the environment. They are approved for food packaging by every regulatory agency in the world that sets food packaging regulations for polymers.

APPLICATION

PVDC resins and films are mainly used for barrier in:

  • Food and pharmaceutical packaging
  • Sterilized medical packaging
  • Unit packaging for hygiene and cosmetic products

As a packaging material, PVDC possesses an outstanding sealing property. Packing food with PVDC can extend the food’s quality guarantee period and at the same time, provides good protection of the food’s colour, smell and taste.

This article further discusses the following details:

  • PVDC Latex applications
  1. Film coating
  2. Paper coating
  3. Impregnation in /coating on polyurethane foam 
  • Manufacturing Process
  • Global Scenario 
  1. Global packaging use pattern of PVDC polymers
  2. Demand driver
  3. Growth
  4. Important Global Manufacturers
  5. Producers in China 
  • Indian Scenario
  1. Indian producers
  2. Sample of Imports in India 
ACYCLOVIR - ANTI VIRAL DRUG - PRODUCT OUTLOOK

Acyclovir is a synthetic purine nucleoside analogue with in vitro and in vivo inhibitory activity against herpes simplex virus types 1 (HSV-1), 2 (HSV-2) and varicela-zoster virus (VZV)

Generic Name

Acyclovir

Chemical name

Acycloguanosine2-Amino-1,9-dihydro-9-[2-hydroxy ethoxy) methyl]-6H-purin-6-one

Drug class

Antiviral

CAS No.

59277-89-3

Appearance

White, crystalline powder

Molecular formula

C 8 H 11 N 5 O 3

Bioavailability

20%

Routes of administration

Oral, intravenous, topical

Formulated Form of the Drug:

  • Capsules
  • Tablets
  • Suspension
  • Cream
  • Injection

Patent status

Original patent holder

Glaxo Wellcome

FDA Approval

March 1982 June 1998 for the supplemental indication of treatment of herpes simplex virus infections

Year of introduction in the world market

1985

Patent Expiry date

22 nd April 1997

This article discusses the following details

  • Details on approval
  • Major Global Producers
  • Global price
  • Global Market for Acyclovir
  • Manufacturing Technologies
  1. Product outlook
  2. Thrust area of use
  3. Merits
  4. Demerits 
  • SWOT Analysis
  1. Strength
  2. Weakness
  3. Opportunities 
PSYLLIUM - DIETARY FIBER SUPPLEMENT

Contributed by: 

Pradeep Dwivedi
Manager Product Development, R&D Division

Sunil Vishwakarma
Microbiologist, Quality control Division

Dr. Adarsh Kumar Agnihotri
Scientist, R & D Division
Organic India Private Limited,
Kamta, P.O. Chinhat, faizabad Road,
Lucknow .227 105 UP, India.

Author for correspondence:

Phone: +91 9936724779 
E-mail: Pradeep@organicindia.com

Dietary fiber, formerly unrecognized for its health benefits, has received much attention in recent years.

Psyllium obtained through the seed husk of Plantago ovata is the most convenient and readily available form of soluble fiber supplementation because in Psyllium husk total dietary content – 86 percent - is made up of 71 percent soluble fiber and 15 percent insoluble fiber. This compares to 15 percent total fiber and only five percent soluble fiber for oat bran. It is widely accepted as playing a significant role in reducing total blood cholesterol, thereby decreasing the risk of coronary heart disease.It has also been credited in helping to alleviate numerous bowel disorders, including colon cancer.

Keeping in view the uses of psyllium husk and other risk assessments, the present study deals with a review of importance of psyllium as a dietary fiber and examines the claims related to it other medicinal properties due to which it is widely used in treatment of irritable bowel syndrome (IBS).

Dietary fibers can be divided into two basic sub groups, soluble and insoluble.

Soluble fiber dissolves in water, and insoluble fiber, as the term describes, does not. Both soluble and insoluble fibers provide bulk in the large intestine and encourage bowel regularity. However, there are important differences between the two. The soluble fiber is to absorb water in the intestinal tract and slow down the amount of time needed to empty the intestine.

Eating these fibers makes one feel full and may help in weight loss. These are also the fibers which are credited with helping to lower bad cholesterol levels in the blood.

Soluble dietary fibers can be obtained by some common sources viz. dried beans and peas, lentils, oats, barley, psyllium husk, sesame seeds, fruits especially bananas, apple, citrus, grapes, apricots, cherries etc. and some vegetables like potatoes, cabbage, carrots
etc.

The fruits and oats are primary sources of soluble fibers while Psyllium which is obtained through the seed husk of Plantago ovata is the most convenient and readily available form of soluble fiber supplementation.

Whereas, insoluble fibers draw water into the intestinal tract, but rather than slowing down digestion, they actually speed it up and increase the amount and frequency of bowel movements. They can be chiefly obtained through various herbs viz.wheat bran, apple and pear skins, peas and carrots, bran cereals, whole-grain breads, vegetables, toasted whole-grain breads, and browned potatoes. The vegetables and wheat bran
are the primary sources of insoluble fiber.

A brief account of the researches on the necessity and uses of Plantago ovata (Psyllium husk) as a dietary fibers are reviewed and discussed in the following paragraphs.

This article contains the following details:

  • Fiber – Which kind is needed?
  • Psyllium as the source of Soluble Fibre
  • Psyllium and Cholesterol
  • Psyllium and Digestive System Function
  • Soluble Fiber – Friend or Foe?
  • Landmark Studies
OTHER STORIES

ONGC'S PERFORMANCE - NO MAJOR DISCOVERIES

ONGC, India’s largest public sector enterprise in a recent report to the government, has acknowledged that it has not been able to make any major discoveries in the past 20 years.

Whatever discoveries were made contributed only about 1.5 million tonnes per annum to the India’s oil output, ONGC said in its annual performance report to the government.

ONGC has accepted the fact that they were not able to make any significant discovery since past 20 years. They had relinquished 12 out of the 15 blocks awarded to them as operator, citing low prospects of these blocks.

According to Directorate General of Hydrocarbons (DGH) website, ONGC has zero success ratio with nil discoveries for the 47 blocks awarded to them. At the same time, private sector companies such as Reliance Industries Ltd have success ratio of 56% with 18 discoveries, according to the same website.

ONGC, said: “Reserves are accreted through new finds, new pools/new pays and extension of existing fields. When we talk of 1.5 mmtpa (million metric tones per annum) from new discoveries in last 15 years, we mean production from isolated fields. The production discoveries around existing producing fields get automatically accounted in the production of the producing fields. For example, the field B-55 from where we are producing nearly 0.84 mmtpa is accounted in the production of Bassein field”.

“Similarly the cluster of Vasai East, B-23 Cluster, B-193 Cluster and B-55 from where we plan to produce about 3 mmtpa would get accounted in the production from Bassein Field. Also, the production from wedge-out areas of Bombay High and B-192 is accounted against Bombay high. The production from these satelite fields around the major producing fields has offset the annual natural. decline of 5 to 6% per annum from the ageing fields.

In the blocks awarded under the new exploration and licensing policy (NELP), ONGC has made six discoveries so far including discovery made in deep water block KG-DWN-98/2, one in ultra deep water with water depth of 2861 metres and another in block MN-OSN-200/2 (Mahanadi shalow water block) at water depth of 988 metres.

NELP was launched by the government in 1999 to attract foreign and private sector players with attractive tax incentives.

ONGC’s gas discovery in the hydrocarbon rich Krishna-Godavari basin early 2007 has not yet been declared commercial by the upstream regulator DGH.Initialy, it was believed to be the largest gas find with estimated reserves of 21 trillion cubic feet (TCF).

But ONGC’s note to the DGH seeking approval for this discovery said that the in place gas reserves were only 2-14 TCF.

Out of a total production of 2 mmtpa of oil and oil equivalent gas (O+OEG) from 28 new discoveries during the year 2005-06, ONGC produced 1.5 mmtpa from its nine new discoveries, namely Laipling gaon, Jambusar, Kuthalam, Periapattinam, Kesanapalli West. Ponamonda, B-173-A,Akholjuni and Kesavadaspalem. These nine fields are isolated fields.

UNEMPLOYABLE ENGINEERS - WHOSE FAULT IT IS?

Contributed by: Mr.Thomas Tharu
e-mail:xteesquare@yahoo.co.uk

This article was prepared in response to an article in the April issue of Nandini Chemical Journal, where it was suggested that the employability problem could be solved mainly by improving the quality of technical education.

The author here expresses the view that the picure is much more complex and industries also have to play a responsible role.

Unemployable engineers is the talk of the day in certain circles. While industries have of late become critical of the engineering colleges for producing what they call unemployable engineers’ in large numbers, whether these educational institutions alone should be held responsible for this label of unemployability, is questionable, says the author.

The intake capacity for engineering education increased several fold, particularly during the past two decades, with the private sector playing an increasing role. This happened mainly in response to the sudden demand for .IT skills., which also resulted in the starting of colleges as business ventures by those with commercial and political clout, often with the unstated objective of cashing in on capitation fees. For quite some time, these institutions had a successful run because the IT industry was wiling to recruit almost anyone, so even colleges with poor infrastructure or quality of staff could earn a good record for job placement and hence attract more students. The situation is now changing in some ways. The IT industry has become more selective in recruiting because supply has more-or-less caught up with the demand for employees. There has also been some revival recently in the manufacturing industries, which had gone into a terrible decline over a long period.

This has created a small but noticeable demand for real engineering skills and consequently the quality of the graduates is being questioned, whereas it was largely irrelevant for doing IT jobs. So now if recruiters complain about unemployable engineers, the educational institutions alone cannot be blamed. Industry as a whole is also partially accountable for this state of affairs.

Till fairly recently (at least before the IT boom), industries had the practice of recruiting trainee engineers for jobs and initiating them through carefully designed and systematic training programmes for a period ranging from a few weeks to two years or so.

Generally, the longer-term trainees would have to execute a bond to serve the organisation for a period of 3 to 5 years. This procedure found widespread acceptance in the past, with both the fresh engineers as well as the industries and the practice of providing on-job training to new recruits was well established.

Obviously, industries at that time knew very well that fresh graduates were not straightaway suitable for performing technical duties and therefore the industries readily accepted the responsibility of providing orientation training, which cannot be done by the engineering colleges and technological institutions.

In the present changed industrial climate (for which there could be many reasons such as global competition or other economic constraints, which go much beyond the topic on hand), organisations are reluctant to invest time and resources for providing training to fresh engineers, but expect them to meet most of the job requirements right away, which is just not possible. Declaring today’s fresh engineers to be .unemployable is thus unfair.

While the plight of many fresh graduate engineers is pathetic and pitiable, the root causes for this situation need to be investigated more critically, as it is a serious matter and a cause of great concern to the nation and society.

In the history of .higher education., the broad function of universities and colleges was to impart an all-round capability for students to function as responsible citizens, even when they acquired the basic degree in a narrow or special discipline like engineering or medicine. The process was expected to build character and provide certain intangible qualities by being exposed to or inspired by reputed faculty and other eminent persons. Specialised training for job skills was always available through various trade and professional institutions at various levels, while advanced theoretical skills were provided by postgraduate or research degrees. Even the so-called business schools. (a fairly recent US invention) are more like the job-oriented training, although the social and prestige value associated with them is high. However, the expectations have been changing rapidly in recent years and there are probably few takers today for the traditional old-fashioned notions regarding education.

There is no obvious solution to the current problem of the colleges being unable to provide what the industry wants. It should be evident that any change in the education system can produce tangible effects only after several years. It requires clear-cut and stable policies about the direction in which changes need to be made, besides suitably trained faculty and administrators to implement such changes. Else we will only keep tinkering with the system in a knee-jerk manner, and no one will be responsible for the increasing chaos.

It is clearly unreasonable to expect colleges to provide at short notice whatever the unpredictable market may demand, which can shift from IT skills or nano-technology to something else tomorrow. Industries should realise the folly of pursuing only profit objectives and expecting .others. to provide trained engineers at no cost to them.

One major factor which has contributed to the problem is the high salaries given to fresh graduates by software companies and BPOs. Such institutions can pay because of the huge profit margin that they generate in operation, with hardly any expenses on infrastructure. As a result, talented engineers are reluctant to join industries which must take costly long- term investment decisions and cannot match the salary offerings by the software sector which can shut shop tomorrow with little loss.

Therefore, a piquant situation has arisen, where those having real aptitude for engineering and technology waste their talents doing dull and stressful (but well-paid) work in software companies. Very often it is social pressure which pushes them into such jobs. In due course, they lose the advantages of their engineering education and become unfit for solving technical problems.

Indeed, it has become common for students to acquire an engineering qualification only because it improves their prospects of getting a lucrative software job (or pursuing a management career). It is very sad to see even children with a genuine flair for the sciences or maths being pushed into engineering courses .because there is no money in science.. All this is an absolute waste of .engineering education., and also results in starving the sciences and humanities.

A very unfortunate consequence of the skewed salary structure has been the flight of existing engineering talent from technical positions. Those who had been doing core jobs in say civil, mechanical, or process industries (other than computer-oriented tasks) found their skils being treated as less relevant, salaries remaining stagnant, or even jobs being lost as companies down-sized or closed down.

In Chennai alone, at least three reputed heavy engineering concerns (in Ambattur, Meenambakkam,and Tondiarpet) which had done many prestigious development jobs in the past, have just not survived.

What happened to their experienced engineers and all the technical staff who manned the machines and did a variety of skilled jobs in the shops or at site or in the design office? The automobile and other mass production industries are largely based on rule-based application of imported technology, with little scope for exercise of engineering skills.

A further consequence of the current situation is the crisis created in the teaching profession. There is almost no incentive for the best or even good students to consider an academic career, at least in India. Those who opt for teaching may be doing so as a fall- back option. Even, faculty with established reputations are being lured by lucrative offers from industry. Under these circumstances, how can industry expect colleges to produce graduates who possess good technical knowledge?

A fresh look at the national level, preceded by informed debate, is required before even beginning to sort out the issues regarding engineering education and employability.

CAPTURE AND STORAGE OF CARBON DIOXIDE DEVELOPING TECHNOLOGIES

To reduce greenhouse gas emissions, one approach is to capture and store the carbon dioxide produced by power stations and industrial facilities.

New European Union regulations stipulate that from 2010, carbon capture devices will be mandatory on al new power stations in European Union.

Such a stipulation became inevitable given that China is now building coal-fired power stations at the rate of one a week.

Carbon capture and storage is by definition a two-part process involving capture of the Carbon dioxide gas and then its sequestration or storage.

The process for capture of carbon dioxide can be carried out by any one of the following methods.

  • Pre-combustion
  • Post-combustion
  • Oxyfuel combustion.

This article further discusses the following details:

  1. Precombustion technology
  2. Post combustion technology
  3. Oxyfuel combustion technology
  4. Sequesteration and storage of Carbon dioxide
  5. Approaches for strong Carbon dioxide
  6. Carbon dioxide hydrates
  7. Prognosis

NANOTECHNOLOGY IN AGRICULTURE AND FOOD PROCESSING

Globally, the potential of nanotechnology in the agrifood sector has been identified and has been attracting significant investments. Currently, over 300 nanofood products are available in the international markets.

According to a recent study by Helmuth Kaiser Consultancy, the nanofood market is expected to surge from USD 2.6 billion in 2004 to USD 20.4 billion by 2010. The report suggests that with more than 50% of the world population, the largest market for nanofood in 2010 will be Asia, led by China.

More than 400 companies around the world are currently active in research and development in nanoagriculture and nanofood. USA is the leader followed by Japan, China, and the EU. Other developing countries actively involved in the research and development of nanofood are: India, South Korea, Iran, and Thailand. Iran, for example, has a focused programme in nanotechnology for the agricultural and food industry.

This article further discusses the following details:

  • Nanotechnology in Agriculture
  • Nanotechnology in Food Industry
  • Conclusion
  • Global Nanofood Market

REVERSE OSMOSIS TECHNOLOGY FOR SEA WATER DESALINATION DEVELOPMENTS IN UAE

Seawater reverse osmosis (SWRO) has been a proven technology for many years, with instalations all over the world. In the past 10 years, SWRO has also become a competitive technology for large installations as well.

Now there are multiple large plants, including Larnaca, Cyprus (54,000 cubic metre per day), Las Palmas, Spain (80,000 cubic metre per day), Carboneras, Spain (120,000 cubic metre per day) Fujairah, UAE (170,500 cubic metre per day) and Ashkelon, Israel (274,000 cubic metre per day).

In particular, SWRO offers much lower energy consumption compared to thermal processes. Since power cost can account for a substantial portion of the total water cost in a desalination plant, it is readily apparent that the energy savings of RO technology make it attractive for large plants.

GUIDELINES FOR CHOICE OF POLYMER FOR MEMBRANE FABRICATION

Important properties for a membrane are strength and flexibility, pore size and permeability, chemical resistance and hydrophilicity. To be cost effective for large scale applications, a membrane polymer need to be made from a commodity product.

Commercial UF/MF membranes are produced from one of six polymers or polymer families, each with their own advantages and disadvantages. Due to the difference in membrane characteristics, different products and operating methods have been developed to take best advantage of the strength of the various membranes.

The PS/PES family and PVDF are now emerging as the dominant polymers of choice for the water industry. Both of these polymer families have excellent properties for the products in which they are used.

This article discusses the factors that have influenced the development of the range of commercial polymers currently available.

Courtesy:Filtration + Separation, April 2007

This article contains the following details:

  • Membrane properties
  • Production process
  • Alternative membrane polymer
  1. PES Membrane
  2. PVDF Membranes
  3. PP and PE Membranes
  • Comparative merits and demerits
  • PVDF vs PES Comparison
  • PROS and CONS of different membranes
OTHER ARTICLES
  • Gas Pipeline Project - Russia Enters
  • Recycling old consumer electronics – Mounting Problem
  • Update on Nanotechnology
  • Two Lupin projects selected for funding
  • Anti Dumping page
  • Update on Carbon trading
  • Technology Leadership Mission-Call for Proposals
  • Update on Biofuel
  • Simultaneous operation of coal mining and CBM extraction
  • BIOHUB-New Initiative for chemicals based on crops
  • R & D Efforts of Central Tobacco Research Institute
  • China News
  • News Round up-International/India
  • Technology Development-International/India
  • Update on Biotechnology
  • Herbal Page
  • Pollution Control Vessel
  • Agro chemical page
  • Renewable source of energy for remove villages
  • Pharma page-International/India
  • Environmental page
  • Energy page
  • Business opportunities
  • New Projects-International
  • Nandini Internet Index
  • Directory of Chemical Industries in China – Manufacturers, Trading Houses and Promotional Organisations- Part XXXXIX
  • Information on Chemical of Your Choice
  • Chemicals Exported at Chennai port during the month of February 2007
  • Chemicals Exported at Visakhapatnam port during the month of March 2007
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