IIT-G develops device that separates oil from water

Agencies
August 19, 2019

New Delhi, Aug 19: Researchers at the Indian Institute of Technology (IIT) Guwahati have developed a device that can continuously separate oil from water by strategic use of fish-scale and lotus-leaf inspired membranes.

The team developed the system of materials by combining the lotus leaf-inspired super-water repellence and fish scale-mimicked underwater super-oil repellence.

The membranes that are super-water repellent in air, and super oil-repellent in water, have been shown to separate complex mixtures of oil and water at practically relevant settings, according to the journal ACS Sustainable Chemistry & Engineering.

Oil-water separation is also important in environmental applications like oil spill management.

The team then developed a prototype of oil-water separation device using these membranes so that the separated oil and water were simultaneously collected in different containers.

"Oil-water separation is of current relevance because many industries, such as mining, textiles, food and petrochemicals, produce massive volumes of oily wastewater, which must be treated before discharge," said Uttam Manna, Assistant Professor, Department of Chemistry, IIT Guwahati.

The lotus leaf for example, is water repellent so that it does not get soggy in its living space, researchers said.

Fish, on the other hand, has a body surface that repels oil in order to survive in polluted waters, they said.

Scientists have studied the surface structures of lotus leaves and fish scales to understand what gives them their superhydrophobicity (super-water repellence) and superoleophobicity (super-oil repellence), so that these structures can be replicated artificially for oil-water separation applications.

Lotus leaf-inspired superhydrophobic materials and fish scale-inspired superoleophobic materials were developed following a single and unique deposition process and tested for gravity-driven removal of oil from water.

While these bio-inspired membranes are individually used to separate oil and water in the recent past, there is accumulation of water or oil on the membrane over time, which blocks further separation.

"There is yet another problem with conventional demonstration, where the superhydrophobic and superoleophobic materials are mostly used for two phase oil/water mixtures," Manna said.

"However, those approaches are inappropriate for separation of three-phase mixtures of heavy oil, light oil and water," he said.

These materials are required to operate under harsh conditions; they are subjected to severe stretching and bending during operation, which make them physically unstable, researchers said.

In order to overcome the problems, Manna and his team developed a system of 'super liquid repellent' materials, by combining the lotus leaf superhydrophobicity and fish scale superoleophobicity.

Layer-by-layer deposition technique was used to obtain alternating layers of 'chemically reactive polymeric nano-complex' and 'amino graphene oxide nanosheets' on a stretchable and fibrous substrate.

The durable and stretchable membranes that the team developed were super-water-repellent in air and super-oil-repellent in water.

"These separation systems allow continuous, parallel and selective separation of various oil/water mixtures, irrespective of surface tension, density, and viscosity of the oil phase and chemical complexity in the water phase," Manna said.

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Agencies
May 30,2020

The GST Council is unlikely to make major changes in the indirect tax structure at its next meeting slated mid June.

A top government source said that the Centre is not in favour of increasing tax rates on any goods or service as it could further impact consumption and demand that is already suppressed due the COVID-19 pandemic and lockdown.

It was widely expected that the GST Council could consider raising tax rates and cess on certain non-essential items to boost revenue for states and the Centre. Several states have reportedly taken an over 80-90 per cent hit in GST collections in April, the official data for which has not yet been released by the Centre.

"The need of the hour is to boost consumption and improve demand. By categorising items into essential and non-essential and then raising taxes on non-essential is not what Centre favours. But, the issue on rates and relief will be decided by the GST Council that is meeting next month," the finance ministry official source quoted above said.

The GST Council is chaired by the Union finance minister and thus the views of the Centre play out strongly in the council meetings.

However, the Council will also have to balance the expectations of the states whose revenues have nosedived after the coronavirus outbreak and wide scale disruption to businesses while they have still not been paid GST compensation since the December-January period.

To the question of wider scale job losses in the period of lockdown as businesses get widely impacted, the official said that the Finance Ministry has asked the labour ministry to collect data on job losses during Covid-19 and is constantly engaging with the ministry to oversee job losses and salary cuts.

On restrictions put on Chinese investment in India, the official clarified that no decision had yet been taken to restrict China through the Foreign Portfolio Investment (FPI) route.

Asked about monetising government debt, the official said that the issue would be looked at when we reach a stage. It has not come to that stage yet.

In the government's over Rs 20 lakh crore economic package, the official defended its structure while suggesting that comparisons with the economic packages of other countries should not be drawn as India's needs were different from others.

"We have gone in more reforms that is needed to give strength to the economy. This is required more in our country," the official source said.

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Agencies
June 29,2020

New Delhi, Jun 29: Witnessing azure skies and breathable air for the last three months, Delhi on Monday recorded deterioration in its air quality, with particulate matter with diameter of 2.5 and 10 microns -- too small to be filtered out of the human body -- standing at 52 and 297 micrograms per cubic respectively.

Gufran Beig, Project Director of System of Air Quality Weather Forecasting and Research (SAFAR), said that the sudden spike in air pollution is due to a mild dust storm blowing from Rajasthan.

"Since the wind direction is changing and moist air is coming in, the air quality in Delhi will become better by tomorrow," Beig told IANS.

Central Pollution Control Board (CPCB) data showed that the overall air quality near Delhi Technical University (DTU) area stood at 326 micrograms per cubic, followed by 308 at Narela and 307 at Mundka.

Out of 36 stations, the AQI in as many as 30 stations was above 200 micrograms per cubic till 1 pm on Monday.

The System of Air Quality Weather Forecasting and Research categorises air quality in the 0-50 range as good, 51-100 as satisfactory, 101-200 as moderate, 201-300 as poor, 301-400 as very poor, and above 400 as severe.

According to SAFAR's website, "PM 10 (coarser dust particle) is the lead pollutant. AQI is likely to improve to moderate category by tomorrow, and further improvement is expected by July 1."

Researchers indicated that PM 10 and PM 2.5 will be 170 and 47 micrograms per cubic on Tuesday.

With no vehicles plying on the roads or industries shut due to the lockdown since March 25, Delhi's air quality had improved drastically.

According to a study conducted by the Indian Institute of Technology (IIT), Delhi, if the low levels of air pollution reached during the lockdown period are maintained, India's annual death toll could reduce by 6.5 lakh.

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Agencies
July 15,2020

New Delhi, Jul 15: The employees union of state-run telecom operator BSNL will stage protests across the country on Thursday on a host of issues including the cancellation of its 4G tender and non-payment of salaries.

All major unions are organising ‘lunch-hour black-flag' demonstrations throughout the country under the banner of All Unions and Association of BSNL (AUAB), said a statement by AUAB. These demonstrations will be organised, by maintaining social distancing and by taking other precautions, like wearing of masks. The BSNL employees will also wear black-badges the whole day on July 16.

The employees body would demand that BSNL should immediately be allowed to roll out its 4G services and the tender should be issued immediately. Further, they want that in the matter of procuring new equipment and upgradation, there should not be any discrimination between BSNL and other private telecom service providers.

Recently, the Centre cancelled the 4G upgradation tender for BSNL as it had decided to come up with fresh specifications for the upgrade process, in a move to keep Chinese technology companies at bay as the border tussle escalated with the northern neighbour.

The Department of Telecommunications (DoT) would issue a fresh tender for the same, and people in the know said that Chinese companies may not be allowed to participate.

"The agitational programme is being organised to express the deep anguish and resentment of the employees against cancellation of BSNL's 4G tender, cancellation of BSNL's proposal for upgradation of its 49,300 BTSs to 4G, abnormal delay in issuing ‘Add on Order' for 4G equipments, inordinate delay in the implementation of BSNL's Revival Package and against the non-settlement of the burning problems of the employees," said the statement.

The umbrella body of BSNL's employees' unions noted that rolling out of 4G services is the backbone for the revival of this telecom PSU, but the recent cancellation of the tender floated by BSNL for procuring 4G equipment at a cost of Rs 9,300 crore, has brought the company back to square one.

It said that BSNL is already having 49,300 base transceiver stations (BTS), which are 4G compatible and through minor upgradation, all these equipment can be converted into 4G BTSs with an investment of about Rs 1,500 crore.

In addition to this, BSNL could have added another 15,000 BTSs, by placing an Add on Order to the existing mobile tender, it added.

Noting that in October 2019, the PSU could have rolled out pan-India 4G services, AUAB said: "Being the sole owner of the company, the Government of India also cannot shirk its responsibility in this matter."

"Adding insult to injury, the tender floated by BSNL to procure 4G equipment, has been cancelled by the government, based on a complaint from the Telecom Equipments and Services Promotional Council (TEPC)," it said.

AUAB said that BSNL is already lagging four years behind the private operators, in terms of 4G and the cancellation of the tender is going to inordinately delay the company's 4G launch.

Saying that TEPC's contention has been to bar foreign companies from participating in BSNL's tender, AUAB statement pointed out that when private operators are procuring equipment from multinationals, "why BSNL alone should be compelled to procure 4G equipments from domestic vendors, whose 4G technology is not tested or proven so far."

It alleged a conspiracy to destabilise BSNL by disrupting its rolling out of 4G services.

AUAB further said that even after the lapse of nine months, the implementation of the much publicised BSNL's Revival Package is moving at a snail's pace.

"Except the swift retrenchment of 79,000 BSNL employees under VRS, all other assurances given in BSNL's Revival Package have been put in cold storage."

The management should ensure that the salary payment of the employees is made on the last working day of every month. Deductions made from employees' salary, on account of "society dues", should immediately be remitted, it said.

Regarding the monetisation of the company's assets under the revival package, the organisation said that the land asset should not be handed over to corporates, at "throwaway" prices.

"These lands should be sold in a transparent manner and at the prevailing market rates. They should not be sold at book value or at circle rates. The AUAB will strictly monitor these dealings," it said.

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