Andrew Black, a non-executive director of Hydrodec, the "clean" oil re-refining group, has topped up his stake in the firm with a £26,500 purchase of shares.

The transaction came just four days after the company announced that revenues for 2011 will come in significantly ahead of 2010.

Sales of the branded Superfine oil rose 12% in the second half of 2011 versus the first six months of the year, giving some indication of the acceleration the company is currently seeing.

There was also encouraging news from the US where Hydrodec received a draft approval from the US Environmental Protection Agency (EPA) to treat polychlorinated biphenyl (PCB) contaminated used oil.

There are still some loose ends to tie up with the EPA, but the company said it is confident it will soon become a "one-stop shop" for companies to dispose of their used transformer oil.

Hydrodec also believes that it will get its "feedstock" (the dirty oil it re-refines) at low, or possibly negative, cost in the US as firms are desperate to get rid of the substance. In other words, Hydrodec may get paid for the feedstock it needs.

Shares have shot up almost 10% over the past week, and are up more than 25% over the last year.

Meanwhile, following a popular trend of late, yet another Tesco director has added a bunch of shares to his basket.

Paola Hanna, a person connected to non-executive director Ken Hanna, 57, bought 25,000 shares at 313.00p each, for a total of £78,250.

Earlier this week Senior Independent Director Patrick Cescau became the third director this month to hit the till with a trolley load of shares, taking his lead from Non-Executive Director Ken Hydon, who stocked up on 30,000 shares, and Non-executive Chairman Richard Broadbent, who also dipped into his back pocket earlier in the month.

All the purchases follow Tesco's recent sales performance which fell below expectations, prompting the company to advise full-year trading profit growth will be around the low end of the range of analysts' expectations.

The share price has dived close to 20% in the past year, 17% in the last month, and fell 2.24% to 322.60p by 15:09 today.


Top Director Buys

Tesco (TSCO)
Director name: Mr Ken Hanna
Amount purchased: 25,000 @ 313.00p
Value: £78,250

HydroDec Group (HYR)
Director name: Mr Andrew Black
Amount purchased: 250,000 @ 10.60p
Value: £26,500


Top Director Sells

Chemring Group (CHG)
Director name: Dr Dr David Price
Amount sold: 42,315 @ 388.46p
Value: £164,377

Chemring Group (CHG)
Director name: Ms Sarah Ellard
Amount sold: 12,058 @ 388.46p
Value: £46,841

Related share prices
Tesco (TSCO) share price
Chemring Group (CHG) share price
HydroDec Group (HYR) share price